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Zhang Z, Zhang H, Wu G, Xu X, Cao R, Wan Q, Xu H, Wang J, Huang T, Wen G. The aggregation characteristics of Aspergillus spores under various conditions and the impact on LPUV inactivation: Comparisons with chlorine-based disinfection. Water Res 2024; 253:121323. [PMID: 38377927 DOI: 10.1016/j.watres.2024.121323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/30/2024] [Accepted: 02/14/2024] [Indexed: 02/22/2024]
Abstract
Aggregation is the primary step prior to fungal biofilm development. Understanding the attributes of aggregation is of great significance to better control the emergence of waterborne fungi. In this study, the aggregation of Aspergills spores (A. flavus and A. fumigatus) under various salt, culture medium, and humic acid (HA) conditions was investigated for the first time, and the inactivation via low-pressure ultraviolet (LPUV) upon aggregated Aspergillus spores was also presented. The aggregation efficiency and size of aggregates increased over time and at low salt (NaCl and CaCl2) concentration (10 mM) while decreasing with the continuous increase of salt concentration (100 and 200 mM). Increasing the concentration of culture medium and HA promoted the aggregation of fungal spores. Spores became hydrated, swelled, and secreted more viscous substances during the growth period, which accelerated the aggregation process. Results also suggested that fungal spores aggregated more easily in actual water, posing a high risk of biohazard in real-life scenarios. Inactivation efficiency by LPUV decreased with higher aggregation degrees due to the protection from the damaged spores on the outer layer and the shielding of pigments in the cell wall. Compared to chlorine-based disinfection, the aggregation resulted in the extension of shoulder length yet neglectable change of inactivation rate constant under LPUV treatment. Further investigation of cell membrane integrity and intracellular reactive oxygen species was conducted to elucidate the difference in mechanisms between various techniques. This study provides insight into the understanding and controlling of the aggregation of fungal spores.
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Affiliation(s)
- Zhenghong Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Huan Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Huining Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China.
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2
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Guo Q, Wang M, Jin S, Ni H, Wang S, Chen J, Zhao W, Fang Z, Li Z, Liu H. Photoaged microplastics enhanced the antibiotic resistance dissemination in WWTPs by altering the adsorption behavior of antibiotic resistance plasmids. Sci Total Environ 2024; 919:170824. [PMID: 38340861 DOI: 10.1016/j.scitotenv.2024.170824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 02/06/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Growing concerns have raised about the microplastic eco-coronas in the ultraviolet (UV) disinfection wastewater, which accelerated the pollution of antibiotic resistance genes (ARGs) in the aquatic environment. As the hotspot of gene exchange, microplastics (MPs), especially for the UV-aged MPs, could alter the spread of ARGs in the eco-coronas and affect the resistance of the environment through adsorbing antibiotic resistant plasmids (ARPs). However, the relationship between the MP adsorption for ARPs and ARG spreading characteristics in MP eco-corona remain unclear. Herein, this study explored the distribution of ARGs in the MP eco-corona through in situ investigations of the discharged wastewater, and the adsorption behaviors of MPs for ARPs by in vitro adsorption experiments and in silico calculations. Results showed that the adsorption capacity of MPs for ARPs was enhanced by 42.7-48.0 % and the adsorption behavior changed from monolayer to multilayer adsorption after UV-aging. It was related to the increased surface roughness and oxygen-containing functional groups of MPs under UV treatment. Moreover, the abundance of ARGs in MP eco-corona of UV-treated wastewater was 1.33-1.55 folds higher than that without UV treatment, promoting the proliferation of drug resistance. DFT and DLVO theoretical calculations indicated that the MP-ARP interactions were dominated by electrostatic physical adsorption, endowing the aged MPs with low potential oxygen-containing groups to increase the electrostatic interaction with ARPs. Besides, due to the desorption of ARPs on MPs driven by the electrostatic repulsion, the bioavailability of ARGs in the MP eco-coronas was increased with pH and decreased with salinity after the wastewater discharge. Overall, this study advanced the understanding of the adsorption behavior of MPs for ARPs and provided inspirations for the evaluation of the resistance spread in the aquatic environment mediated by MP eco-coronas.
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Affiliation(s)
- Qian Guo
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Mengjun Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Siyuan Jin
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Haohua Ni
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Shuping Wang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Jie Chen
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Wenlu Zhao
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Zhiguo Fang
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Zhiheng Li
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China.
| | - Huijun Liu
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
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Dwinandha D, Elsamadony M, Gao R, Fu QL, Liu J, Fujii M. Interpretable Machine Learning and Reactomics Assisted Isotopically Labeled FT-ICR-MS for Exploring the Reactivity and Transformation of Natural Organic Matter during Ultraviolet Photolysis. Environ Sci Technol 2024; 58:816-825. [PMID: 38111239 DOI: 10.1021/acs.est.3c05213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Isotopically labeled FT-ICR-MS combined with multiple post-analyses, including interpretable machine learning (IML) and a paired mass distance (PMD) network, was employed to unravel the reactivity and transformation of natural organic matter (NOM) during ultraviolet (UV) irradiation. FT-ICR-MS analysis was used to assign formulas, which were classified on the basis of their molecular compositions and structural categories. Isotope (deuterium, D) labeling was utilized to unequivocally determine the photochemical products and examine the development of OD radical-mediated NOM transformation. With regard to the reactive molecular formulas, CHOS formulas exhibited the highest reactivity (86.5% of precursors disappeared) followed by CHON (53.4%) and CHO (24.6%) formulas. With regard to structural categories, the degree of reactivity decreased in the following order: tannins > condensed aromatics > lignin/CRAMs. The IML algorithm demonstrated that the crucial features governing the reactivity of formulas were the molecular weight, DBE-O, NOSC, and the presence of heteroatoms (i.e., N and S), suggesting that the large and unsaturated compounds containing S and N are more prone to photodegradation. The reactomics approach using the PMD network further indicated that 11 specific molecular formulas in the CHOS and CHO class served as hubs, implying a higher photoreactivity and participation in a range of transformations. The isotope labeling analyses also found that, among the reactions observed, hydroxylation (i.e., +OD) is dominant for lignin/CRAMs and condensed aromatics, and formulas containing ≤10 D atoms were developed. Overall, this study, by adopting rigorous and interpretable techniques, could provide in-depth insights into the molecular-level dynamics of NOM under UV irradiation.
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Affiliation(s)
- Dhimas Dwinandha
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Mohamed Elsamadony
- Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
- Center for Refining and Advanced Chemicals, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Rongjun Gao
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
| | - Qing-Long Fu
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Jibao Liu
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Manabu Fujii
- Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan
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Thant SW, Takaichi A, Kajima Y, Mohamed A, Nozaki K, Takahashi H, Chen P, Hanawa T, Wakabayashi N. Effect of ultraviolet irradiation treatment on shear bond strength between polymethyl methacrylate and cobalt-chromium-molybdenum alloy. Dent Mater J 2023; 42:748-755. [PMID: 37612058 DOI: 10.4012/dmj.2023-058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
We aimed to elucidate the effects of ultraviolet (UV) irradiation on the shear bond strength (SBS) between heat-cured polymethyl methacrylate (PMMA) and a Co-Cr-Mo alloy. Disk-shaped Co-Cr-Mo alloy prepared by casting were subjected to different UV treatment times (0, 15, and 30 min). To determine the effect of UV treatment on surface properties of the alloy, surface roughness, wettability, and chemical compositions were analyzed. To evaluate the SBS, cylindrical PMMA was bonded to the UV-treated alloy, and subsequently subjected to the SBS test after 24 h of storage at room temperature or following 10,000 thermal cycles (n=10/group). After the UV treatment, the surface roughness remained unchanged, but oxidation resulted in the surface exhibiting greater hydrophilic characteristics. The UV-treated group showed significantly higher SBS values than those of the non-treated group (p<0.001). These results suggested that UV treatment-mediated oxidation improved the bond strength between PMMA and Co-Cr-Mo alloy.
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Affiliation(s)
- San Win Thant
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Atsushi Takaichi
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Yuka Kajima
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Amr Mohamed
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Kosuke Nozaki
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Hidekazu Takahashi
- Course for Oral Health Engineering, Faculty of Dentistry, Tokyo Medical and Dental University
| | - Peng Chen
- Metallic Biomaterials, Biomedical Materials, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University
| | - Takao Hanawa
- Metallic Biomaterials, Biomedical Materials, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University
| | - Noriyuki Wakabayashi
- Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
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Oh C, Kim T, Ju MW, Kim MY, Park SH, Lee GH, Kim H, Kim S, Kim BS. Influence of Channel Surface with Ozone Annealing and UV Treatment on the Electrical Characteristics of Top-Gate InGaZnO Thin-Film Transistors. Materials (Basel) 2023; 16:6161. [PMID: 37763439 PMCID: PMC10532450 DOI: 10.3390/ma16186161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023]
Abstract
The effect of the channel interface of top-gate InGaZnO (IGZO) thin film transistors (TFTs) on the electrical properties caused by exposure to various wet chemicals such as deionized water, photoresist (PR), and strippers during the photolithography process was studied. Contrary to the good electrical characteristics of TFTs including a protective layer (PL) to avoid interface damage by wet chemical processes, TFTs without PL showed a conductive behavior with a negative threshold voltage shift, in which the ratio of Ga and Zn on the IGZO top surface reduced due to exposure to a stripper. In addition, the wet process in photolithography increased oxygen vacancy and oxygen impurity on the IGZO surface. The photo-patterning process increased donor-like defects in IGZO due to organic contamination on the IGZO surface by PR, making the TFT characteristics more conductive. The introduction of ozone (O3) annealing after photo-patterning and stripping of IGZO reduced the increased defect states on the surface of IGZO due to the wet process and effectively eliminated organic contamination by PR. In particular, by controlling surface oxygens on top of the IGZO surface excessively generated with O3 annealing using UV irradiation of 185 and 254 nm, IGZO TFTs with excellent current-voltage characteristics and reliability could be realized comparable to IGZO TFTs containing PL.
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Affiliation(s)
- Changyong Oh
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
- E·ICT-Culture·Sports Track, Korea University, Sejong 30019, Republic of Korea
| | - Taehyeon Kim
- Memory Diffusion Technology Team, Samsung Electronics, Pyeongtaek-si 17786, Republic of Korea;
| | - Myeong Woo Ju
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
- E·ICT-Culture·Sports Track, Korea University, Sejong 30019, Republic of Korea
| | - Min Young Kim
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
| | - So Hee Park
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
| | - Geon Hyeong Lee
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
| | - Hyunwuk Kim
- Display Development Division, ENF Technology Co., Ltd., Yongin-si 17084, Republic of Korea; (H.K.); (S.K.)
| | - SeHoon Kim
- Display Development Division, ENF Technology Co., Ltd., Yongin-si 17084, Republic of Korea; (H.K.); (S.K.)
| | - Bo Sung Kim
- Department of Applied Physics, Korea University, Sejong 30019, Republic of Korea; (C.O.); (M.W.J.); (M.Y.K.); (S.H.P.); (G.H.L.)
- E·ICT-Culture·Sports Track, Korea University, Sejong 30019, Republic of Korea
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Rocha-Cuervo JJ, Uribe-Lam E, Treviño-Quintanilla CD, Melo-Maximo DV. Sputtering Plasma Effect on Zinc Oxide Thin Films Produced on Photopolymer Substrates. Polymers (Basel) 2023; 15:polym15102283. [PMID: 37242858 DOI: 10.3390/polym15102283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/09/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
This work presents a post-cured treatment alternative for photopolymer substrates considering the plasma produced via the sputtering process. The sputtering plasma effect was discussed, analyzing the properties of zinc/zinc oxide (Zn/ZnO) thin films deposited on photopolymer substrates, with and without ultraviolet (UV) treatment as a post-treatment process, after manufacturing. The polymer substrates were produced from a standard Industrial Blend resin and manufactured using stereolithography (SLA) technology. After that, the UV treatment followed the manufacturer's instructions. The influence of the sputtering plasma as an extra treatment during the deposition of the films was analyzed. Characterization was performed to determine the microstructural and adhesion properties of the films. The results showed the effect of plasma as a post-cured treatment alternative: fractures were found in thin films deposited on polymers with previous UV treatment. In the same way, the films showed a repetitive printing pattern due to the phenomenon of polymer shrinkage caused by the sputtering plasma. The plasma treatment also showed an effect on the thicknesses and roughness values of the films. Finally, according to VDI-3198 standards, coatings with acceptable adhesion failures were found. The results provide attractive properties of Zn/ZnO coatings on polymeric substrates produced by additive manufacturing.
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Affiliation(s)
- Juan Jesus Rocha-Cuervo
- Tecnologico de Monterrey, School of Engineering and Sciences, Estado de Mexico Campus, Atizapán 52926, Mexico
| | - Esmeralda Uribe-Lam
- Tecnologico de Monterrey, School of Engineering and Sciences, Queretaro 76130, Mexico
| | - Cecilia Daniela Treviño-Quintanilla
- Tecnologico de Monterrey, School of Engineering and Sciences, Queretaro 76130, Mexico
- Tecnologico de Monterrey, Institute of Advanced Materials for Sustainable Manufacturing, Ave. Eugenio Garza Sada 2501, Monterrey 64849, Mexico
| | - Dulce Viridiana Melo-Maximo
- Tecnologico de Monterrey, School of Engineering and Sciences, Estado de Mexico Campus, Atizapán 52926, Mexico
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Kazberova A, Solovov R, Orlichenia V. Phosphorylated Cotton Cellulose as a Matrix for Generating Chlorine Dioxide. Polymers (Basel) 2023; 15:polym15040967. [PMID: 36850250 PMCID: PMC9967223 DOI: 10.3390/polym15040967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/09/2023] [Accepted: 02/11/2023] [Indexed: 02/18/2023] Open
Abstract
Currently, developing disinfectant materials is of utmost importance. A significant advantage of our fabric is its reusability. The disinfectants based on a natural polymer of cellulose have been barely investigated. Our work presents a modified cellulose material, and the data obtained for the first time on the chlorine dioxide generation process when treating the material with a sodium chlorite alcohol solution. A method of applying NaClO2 onto the fabric by impregnating it with a solution sprayed by an aerosol generator is proposed. This kind of fabric is capable of withstanding multiple usages after pre-washing and rinsing. The lowest alcohols-methanol, ethanol and isopropanol-are proposed as optimal solvents. It was shown that the phosphorylated cotton cellulose fabric impregnated with this solution generates chlorine dioxide during the first 25-35 min. Neither humidity nor expedites improve the process of releasing the chlorine dioxide, but high moisture content in the air causes the complete absorption of ClO2 by microdrops and its removal from the gas environment. A promising technique for removing the excess ClO2 by the means of UV treatment is proposed: after 15 min of treating ClO2 in the gas phase, it disappears entirely. These materials could be used as disinfectants in different industries, such as food and industrial manufacturing.
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Affiliation(s)
- Anfisa Kazberova
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, 40 Obruchev Street, 117342 Moscow, Russia
| | - Roman Solovov
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, 40 Obruchev Street, 117342 Moscow, Russia
| | - Verbina Orlichenia
- Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, 40 Obruchev Street, 117342 Moscow, Russia
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Truschi S, Baldi A, Bruschi P, Cacciari I, Marvasi M, Lenzi A. Foliar Roughness and Water Content Impact on Escherichia coli Attachment in Baby Leafy Greens. Biology (Basel) 2023; 12. [PMID: 36671794 DOI: 10.3390/biology12010102] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/12/2023]
Abstract
Understanding the relation between the susceptibility of different leafy greens to human pathogen contamination and leaf traits can contribute to increase the food safety of the fresh vegetable industry. The aim of this research was to evaluate the susceptibility to E. coli ATCC 35218 attachment in 30 accessions of baby leaves, and to identify leaf traits potentially involved in the contamination. The accessions were surface inoculated with a bacterial suspension containing 1 × 107 cells/mL and the attachment was measured 1.5 h after inoculation. Significant differences in attachment were detected between the accessions for p ≤ 0.05. The three most and the three least susceptible accessions were selected and characterized for leaf micro-morphological traits (stomata density and size, surface roughness) and water content. Scanning electron microscopy was used to analyse the stomatal parameters. Roughness was measured by an innovative portable 3D digital microscope. No significant correlation between the attachment of E. coli ATCC 35218 and stomatal parameters was detected, while the attachment was positively correlated with roughness and water content. The E. coli ATCC 35218 population in surface-inoculated leaves was also measured after a UV treatment, which was found to be less effective in reducing bacterial contamination in the rougher leaves. This result suggested that roughness offers UV protection, further highlighting its impact on the microbiological safety of baby leafy greens.
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Turck D, Bohn T, Castenmiller J, De Henauw S, Hirsch-Ernst KI, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Pelaez C, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Cubadda F, Frenzel T, Heinonen M, Marchelli R, Neuhäuser-Berthold M, Poulsen M, Prieto Maradona M, Schlatter JR, van Loveren H, Gerazova-Efremova K, Roldán-Torres R, Knutsen HK. Safety of vitamin D 2 mushroom powder as a Novel food pursuant to Regulation (EU) 2015/2283 (NF 2019/1471). EFSA J 2022; 20:e07326. [PMID: 35706680 PMCID: PMC9186149 DOI: 10.2903/j.efsa.2022.7326] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on vitamin D2 mushroom powder as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is produced from Agaricus bisporus mushroom that has been exposed to ultraviolet (UV) irradiation to induce the conversion of provitamin D2 (ergosterol) to vitamin D2 (ergocalciferol). The NF contains levels of vitamin D in the form of vitamin D2 in the range of 125-375 µg/g. The information provided on the production process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF as an ingredient in a variety of foods and beverages in amounts that result in either 1.125 or 2.25 µg vitamin D2 per 100 g or 100 mL of the food as consumed. The applicant also intends to add the NF in food supplements, for infants from 7 to 11 months at a maximum of 10 µg vitamin D2/day and of 15 µg vitamin D2/day for individuals aged 1 year or older, as well as in foods for special medical purposes (FSMPs) and total and meal diet replacement for weight control. For the adult population, the maximum intended use level in FSMPs is 15 µg vitamin D2/day and 5 µg vitamin D2/meal in total and meal diet replacement for weight control. The Panel concludes that the NF is safe under the proposed conditions of use. The Panel notes uncertainty regarding the calculated combined exposures to vitamin D for the general population, given the fact that the range of foods fortified with vitamin D has increased over the years, as well as the marketing of high-dose vitamin D supplements.
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10
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Wang J, Pan H, Xu X, Jin H, Ma W, Xiong S, Bao Q, Tang Z, Ma Z. Li-Doped ZnO Electron Transport Layer for Improved Performance and Photostability of Organic Solar Cells. ACS Appl Mater Interfaces 2022; 14:12450-12460. [PMID: 35235287 DOI: 10.1021/acsami.1c22093] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Organic solar cells (OSCs) based on an inverted architecture generally have better stability compared to those based on a standard architecture. However, the photoactive area of the inverted solar cells increases under ultraviolet (UV) or solar illuminatiom because of the too-high conductivity of the UV-illuminated zinc oxide (ZnO) interlayer. This limits the potential of the inverted solar cells for industrial applications. Herein, lithium-doped ZnO (Li-ZnO) films are employed as the cathode interlayer to construct inverted OSCs. The incorporation of Li ions is found to reduce the lateral conductivity of the UV-treated ZnO films because of the presence of Li ions, preventing the high-quality-growth of ZnO nanocrystals. This addresses the problem of having too-high conductivity in the UV-treated ZnO layer, causing the increased photoactive area of inverted solar cells. The overall performance of the solar cell is shown to be higher after the incorporation of Li ions in the ZnO layer, mainly due to the increased fill factor (FF), originating from the reduced trap-assisted recombination losses. Finally, the inverted solar cells based on the Li-ZnO interlayer are demonstrated to have a much better long-term stability, as compared to those based on ZnO. This allows the ZnO-based interlayers to be used for the mass production of organic solar cell modules.
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Affiliation(s)
- Jie Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Hailin Pan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Xiaoyun Xu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Hui Jin
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Wenjia Ma
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, Zhejiang, P. R. China
| | - Shaobing Xiong
- Key Laboratory of Polar Materials and Devices, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, P.R. China
| | - Qinye Bao
- Key Laboratory of Polar Materials and Devices, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, P.R. China
| | - Zheng Tang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
| | - Zaifei Ma
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China
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Umar M. From Conventional Disinfection to Antibiotic Resistance Control-Status of the Use of Chlorine and UV Irradiation during Wastewater Treatment. Int J Environ Res Public Health 2022; 19:1636. [PMID: 35162659 DOI: 10.3390/ijerph19031636] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/22/2022] [Accepted: 01/29/2022] [Indexed: 12/10/2022]
Abstract
Extensive use of antibiotics for humans and livestock has led to an enhanced level of antibiotic resistance in the environment. Municipal wastewater treatment plants are regarded as one of the main sources of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the aquatic environment. A significant amount of research has been carried out to understand the microbiological quality of wastewater with respect to its antibiotic resistance potential over the past several years. UV disinfection has primarily been used to achieve disinfection, including damaging DNA, but there has been an increasing use of chlorine and H2O2-based AOPs for targeting genes, including ARGs, considering the higher energy demands related to the greater UV fluences needed to achieve efficient DNA damage. This review focuses on some of the most investigated processes, including UV photolysis and chlorine in both individual and combined approaches and UV advanced oxidation processes (AOPs) using H2O2. Since these approaches have practical disinfection and wastewater treatment applications globally, the processes are reviewed from the perspective of extending their scope to DNA damage/ARG inactivation in full-scale wastewater treatment. The fate of ARGs during existing wastewater treatment processes and how it changes with existing treatment processes is reviewed with a view to highlighting the research needs in relation to selected processes for addressing future disinfection challenges.
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12
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Ikeda T, Ueno T, Saruta J, Hirota M, Park W, Ogawa T. Ultraviolet Treatment of Titanium to Enhance Adhesion and Retention of Oral Mucosa Connective Tissue and Fibroblasts. Int J Mol Sci 2021; 22:12396. [PMID: 34830275 DOI: 10.3390/ijms222212396] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 01/16/2023] Open
Abstract
Peri-implantitis is an unsolved but critical problem with dental implants. It is postulated that creating a seal of gingival soft tissue around the implant neck is key to preventing peri-implantitis. The objective of this study was to determine the effect of UV surface treatment of titanium disks on the adhesion strength and retention time of oral connective tissues as well as on the adherence of mucosal fibroblasts. Titanium disks with a smooth machined surface were prepared and treated with UV light for 15 min. Keratinized mucosal tissue sections (3 × 3 mm) from rat palates were incubated for 24 h on the titanium disks. The adhered tissue sections were then mechanically detached by agitating the culture dishes. The tissue sections remained adherent for significantly longer (15.5 h) on the UV-treated disks than on the untreated control disks (7.5 h). A total of 94% of the tissue sections were adherent for 5 h or longer on the UV-treated disks, whereas only 50% of the sections remained on the control disks for 5 h. The adhesion strength of the tissue sections to the titanium disks, as measured by tensile testing, was six times greater after UV treatment. In the culture studies, mucosal fibroblasts extracted from rat palates were attached to titanium disks by incubating for 24, 48, or 96 h. The number of attached cells was consistently 15–30% greater on the UV-treated disks than on the control disks. The cells were then subjected to mechanical or chemical (trypsinization) detachment. After mechanical detachment, the residual cell rates on the UV-treated surfaces after 24 and 48 h of incubation were 35% and 25% higher, respectively, than those on the control surfaces. The remaining rate after chemical detachment was 74% on the control surface and 88% on the UV-treated surface for the cells cultured for 48 h. These trends were also confirmed in mouse embryonic fibroblasts, with an intense expression of vinculin, a focal adhesion protein, on the UV-treated disks even after detachment. The UV-treated titanium was superhydrophilic, whereas the control titanium was hydrophobic. X-ray photoelectron spectroscopy (XPS) chemical analysis revealed that the amount of carbon at the surface was significantly reduced after UV treatment, while the amount of TiOH molecules was increased. These ex vivo and in vitro results indicate that the UV treatment of titanium increases the adhesion and retention of oral mucosa connective tissue as a result of increased resistance of constituent fibroblasts against exogenous detachment, both mechanically and chemically, as well as UV-induced physicochemical changes of the titanium surface.
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Vitzilaiou E, Kuria AM, Siegumfeldt H, Rasmussen MA, Knøchel S. The impact of bacterial cell aggregation on UV inactivation kinetics. Water Res 2021; 204:117593. [PMID: 34482094 DOI: 10.1016/j.watres.2021.117593] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/14/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Reconditioning of food processing water streams for reuse is an increasingly common water management practice in the food industry and UV disinfection is often employed as part of the water treatment. Several factors may impact the effect of UV radiation. Here, we aim to assess the impact of cell aggregation on UV inactivation kinetics and investigate if UV exposure induces aggregation. Three strains, isolated from food processing water reuse lines (Raoultella ornithinolytica, Pseudomonas brenneri, Rothia mucilaginosa) and both an aggregating and a non-aggregating strain of Staphylococcus aureus were exposed to UVC light at 255 nm using UV LED equipment. Total Viable Count and phase-contrast microscopy, coupled with image analysis, were used to compare the UV inactivation kinetics with the average particle size for a range of UV doses. Tailing effect, seen as a strong reduction in inactivation rate, was observed for all strains at higher UV doses (industrial strains ≥ 50 or 120 mJ/cm2, S. aureus strains ≥ 40 or 60 mJ/cm2). The naturally aggregating strains were more UV tolerant, both within and between species. When aggregates of S. aureus were broken, UV tolerance decreased. For the processing water isolates, the lowest applied UV dose (25 mJ/cm2) significantly increased the average particle size. Application of higher UV doses obtained with longer exposure times did not further increase the particle size compared with untreated samples. For the S. aureus strains, however, no consistent change in average particle size was observed due to UV. Our results demonstrate that aggregating strains have a higher degree of protection and that UV radiation induces aggregation in some, but not all bacteria. A better understanding of the mechanisms governing microbial aggregation and survival during UV treatment could help to improve UV applications and predictions of microbial inactivation.
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Affiliation(s)
- Eirini Vitzilaiou
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark.
| | - Asaph M Kuria
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
| | - Henrik Siegumfeldt
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
| | - Morten A Rasmussen
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark; COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Susanne Knøchel
- Microbiology and Fermentation, Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, DK-1958, Frederiksberg C, Denmark
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Ikeda T, Okubo T, Saruta J, Hirota M, Kitajima H, Yanagisawa N, Ogawa T. Osteoblast Attachment Compromised by High and Low Temperature of Titanium and Its Restoration by UV Photofunctionalization. Materials (Basel) 2021; 14:5493. [PMID: 34639891 DOI: 10.3390/ma14195493] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/10/2021] [Accepted: 09/15/2021] [Indexed: 01/19/2023]
Abstract
Titanium implants undergo temperature fluctuations during manufacturing, transport, and storage. However, it is unknown how this affects their bioactivity. Herein, we explored how storage (six months, dark conditions) and temperature fluctuations (5-50 °C) affected the bioactivity of titanium implants. Stored and fresh acid-etched titanium disks were exposed to different temperatures for 30 min under wet or dry conditions, and their hydrophilicity/hydrophobicity and bioactivity (using osteoblasts derived from rat bone marrow) were evaluated. Ultraviolet (UV) treatment was evaluated as a method of restoring the bioactivity. The fresh samples were superhydrophilic after holding at 5 or 25 °C under wet or dry conditions, and hydrophilic after holding at 50 °C. In contrast, all the stored samples were hydrophobic. For both fresh and stored samples, exposure to 5 or 50 °C reduced osteoblast attachment compared to holding at 25 °C under both wet and dry conditions. Regression analysis indicated that holding at 31 °C would maximize cell attachment (p < 0.05). After UV treatment, cell attachment was the same or better than that before temperature fluctuations. Overall, titanium surfaces may have lower bioactivity when the temperature fluctuates by ≥20 °C (particularly toward lower temperatures), independent of the hydrophilicity/hydrophobicity. UV treatment was effective in restoring the temperature-compromised bioactivity.
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15
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Ghosh S, Bitra VS, S Dasi D, Godugula V. Detoxification of jatropha kernel meal to utilize it as aqua-feed. J Sci Food Agric 2021; 101:5089-5096. [PMID: 33570746 DOI: 10.1002/jsfa.11154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 02/03/2021] [Accepted: 02/11/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Jatropha is an oilseed crop with high kernel oil (55-58%) and protein (26-29%) contents, which makes it a good source of biodiesel and animal/aqua-feed. However, the presence of anti-nutritional toxins, such as phorbol esters, lectins, trypsin inhibitor, phytate, and saponins, restricts its use as feed. This paper describes chemical, ultraviolet (UV) radiation, and biological treatments for detoxification of jatropha kernel meal. Raw, defatted, and one-time and two-times mechanically expressed oil samples were analyzed for toxins. Chemical treatment involved heating with 90% methanol and 4% sodium hydroxide. UV treatment was carried out at UV light intensity of 53.4 mW cm-2 for 30 min. For biological treatment, cell-free extract from Pseudomonas aeruginosa (strain PAO1) was mixed with kernel meal for detoxification. RESULTS Among treatments, chemical treatment was most effective in reducing all toxins, with phorbol esters in the range 0.034-0.052 mg g-1 , lectin 0.082-10.766 mg g-1 , trypsin inhibitor 10.499-11.350 mg g-1 , phytate 2.475-5.769 mg g-1 , and saponins 0.044-0.098 mg g-1 . Biological treatment reduced all toxins except phytate, whereas UV treatment could not reduce any of toxins and, hence, cannot be used for aqua-feed preparation. Pellets prepared from chemically detoxified kernel meal with the least oil content (defatted) resulted in the highest strength (70.93 N). CONCLUSION Chemically treated jatropha kernel meal can be used for aqua-feed pellet preparation because of its low toxin content. The highest compressive strength was obtained for pellets with the least oil content (defatted). Biological treatment time must have been extended for many hours instead of 24 h. Jatropha kernel meal treated chemically can be recommended for aqua-feed manufacturing. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Subarna Ghosh
- Department of Processing and Food Engineering, Dr N.T.R. College of Agricultural Engineering, Bapatla, India
| | - Venkata Sp Bitra
- Department of Processing and Food Engineering, Dr N.T.R. College of Agricultural Engineering, Bapatla, India
| | - Daniel S Dasi
- College of Food Science and Technology, Pulivendula, India
| | - Veeraprasad Godugula
- Department of Farm Machinery and Power Engineering, Dr N.T.R. College of Agricultural Engineering, Bapatla, India
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Tabuchi M, Hamajima K, Tanaka M, Sekiya T, Hirota M, Ogawa T. UV Light-Generated Superhydrophilicity of a Titanium Surface Enhances the Transfer, Diffusion and Adsorption of Osteogenic Factors from a Collagen Sponge. Int J Mol Sci 2021; 22:6811. [PMID: 34202795 DOI: 10.3390/ijms22136811] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/14/2021] [Accepted: 06/21/2021] [Indexed: 02/07/2023] Open
Abstract
It is a significant challenge for a titanium implant, which is a bio-inert material, to recruit osteogenic factors, such as osteoblasts, proteins and blood effectively when these are contained in a biomaterial. The objective of this study was to examine the effect of ultraviolet (UV)-treatment of titanium on surface wettability and the recruitment of osteogenic factors when they are contained in an atelocollagen sponge. UV treatment of a dental implant made of commercially pure titanium was performed with UV-light for 12 min immediately prior to the experiments. Superhydrophilicity on dental implant surfaces was generated with UV-treatment. The collagen sponge containing blood, osteoblasts, or albumin was directly placed on the dental implant. Untreated implants absorbed only a little blood from the collagen sponge, while the UV-treated implants absorbed blood rapidly and allowed it to spread widely, almost over the entire implant surface. Blood coverage was 3.5 times greater for the UV-treated implants (p < 0.001). Only 6% of the osteoblasts transferred from the collagen sponge to the untreated implants, whereas 16% of the osteoblasts transferred to the UV-treated implants (p < 0.001). In addition, a weight ratio between transferred albumin on the implant and measured albumin adsorbed on the implant was 17.3% in untreated implants and 38.5% in UV-treated implants (p < 0.05). These results indicated that UV treatment converts a titanium surface into a superhydrophilic and bio-active material, which could recruite osteogenic factors even when they were contained in a collagen sponge. The transfer and subsequent diffusion and adsorption efficacy of UV-treated titanium surfaces could be useful for bone formation when titanium surfaces and osteogenic factors are intervened with a biomaterial.
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Turck D, Castenmiller J, De Henauw S, Hirsch‐Ernst KI, Kearney J, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Pelaez C, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Cubadda F, Frenzel T, Heinonen M, Marchelli R, Neuhäuser‐Berthold M, Poulsen M, Maradona MP, Schlatter JR, van Loveren H, Gelbmann W, Knutsen HK. Safety of extended uses of UV-treated baker's yeast as a Novel Food pursuant to Regulation (EU) 2015/2283. EFSA J 2021; 19:e06602. [PMID: 34221146 PMCID: PMC8243754 DOI: 10.2903/j.efsa.2021.6602] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In 2014, the EFSA NDA Panel concluded that UV-treated baker's yeast containing up to 3.5 Mio IU of vitamin D/100 g, is safe under the proposed conditions of use for yeast-leavened breads, rolls and fine bakery wares, and food supplements. Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on an application for an extension of the use of UV-treated baker's yeast as a novel food (NF) pursuant to Regulation (EU) 2015/2283. In this extension of use, the applicant proposed a broad range of food categories to which the NF can be added. On the basis of the proposed uses and maximum use levels, the Panel estimated the potential exposure to vitamin D from the NF and the potential combined exposure to vitamin D including also exposure from the background diet and food supplements. The Panel notes that the upper level (UL) for one age group, i.e. children aged 4-10 years, is exceeded by 4%, when summing up the highest P95 estimate for the background diet (including food supplements) and the highest P95 estimate for vitamin D from the NF under the proposed uses and maximum use levels. The Panel notes, however, the highly conservative approach for estimating the potential intake of vitamin D from the NF, given that the applicant has proposed 34 FoodEx2 level 2 food categories. Thus, the Panel considers that the UL for children aged between 4 and 10 years is highly unlikely to be exceeded. The Panel concludes that the NF is safe under the proposed conditions of use.
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18
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Szczuka A, Berglund-Brown JP, MacDonald JA, Mitch WA. Control of sulfides and coliphage MS2 using hydrogen peroxide and UV disinfection for non-potable reuse of pilot-scale anaerobic membrane bioreactor effluent. Water Res X 2021; 11:100097. [PMID: 33817615 PMCID: PMC8005849 DOI: 10.1016/j.wroa.2021.100097] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/03/2021] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic membrane bioreactors reduce the energy cost of wastewater treatment and meet filtration requirements for non-potable reuse. However, sulfides (H2S/HS-) formed during anaerobic treatment exert a high chlorine demand and inhibit UV disinfection by photon shielding at 254 nm. This study evaluated the feasibility of hydrogen peroxide (H2O2) for sulfide oxidation, UV disinfection for inactivation of MS2 bacteriophage, and chlorine to provide a residual for distribution. H2O2 treatment at pH ≥ 8 favored sulfide oxidation to sulfate in 30 min at a 4:1 H2O2:sulfide stoichiometry. Compared to a 6:1 H2O2:sulfide molar ratio, treatment of anaerobic effluent with 0.5 mM sulfides with a 4:1 H2O2:sulfide molar ratio would increase the applied UV fluence needed for 5-log MS2 inactivation from 180 mJ cm-2 to 225 mJ cm-2. However, the lower H2O2 dose reduced the dose of chlorine needed to quench residual H2O2 and provide a residual for distribution. Treatment at the 4:1 H2O2:sulfide molar ratio was favored, because the cost savings in H2O2 and chlorine reagents outweighed the energy savings associated with UV treatment. However, H2O2/UV/chlorine treatment of anaerobic effluent was cost-competitive with conventional treatment of aerobic effluent for non-potable reuse only for < 285 µM sulfides.
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Affiliation(s)
- Aleksandra Szczuka
- Department of Civil and Environmental Engineering, University of Michigan, 2350 Hayward Street, Ann Arbor, MI 48109, United States
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
| | - Juliana P. Berglund-Brown
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
| | - Jessica A. MacDonald
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
| | - William A. Mitch
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
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Chaudhary AK, Chaitanya K, Vijayakumar RP. Synergistic effect of UV and chemical treatment on biological degradation of Polystyrene by Cephalosporium strain NCIM 1251. Arch Microbiol 2021; 203:2183-91. [PMID: 33620524 DOI: 10.1007/s00203-021-02228-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 01/27/2021] [Accepted: 02/11/2021] [Indexed: 10/22/2022]
Abstract
The present study approaches the capability of Cephalosporium strain NCIM 1251 to degrade pre-treated polystyrene films. Polystyrene was initially treated with UV for the introduction of oxygen molecules in pure polystyrene samples. UV treatment inserts aliphatic ketones functional group in polystyrene whereas it created C-C stretching after chemical treatment in UV-treated polystyrene as analyzed by Fourier-transform infrared spectroscopy (FTIR). The gravimetric study confirmed a decline in the weight of the pre-treated polystyrene by 20.62 ± 1.47% after 8 weeks of the incubation period. pH, total dissolved solids (TDS), and conductivity of mineral salt media were correlated with the extent of biodegradation. Treatment with UV and acid increased the thermal stability of pure polystyrene, whereas thermal stability decreased in pre-treated polystyrene after incubation with Cephalosporium strain NCIM 1251 as studied by Thermogravimetric analysis (TGA). Scanning Electron Microscopy (SEM) analysis observed revisions in the morphology and surface patterns in pre-treated polystyrene after inoculation with Cephalosporium strain NCIM 1251. The observed findings suggest that the Cephalosporium strain NCIM 1251 could be efficient for the decomposition of pre-treated polystyrene.
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Okubo T, Ikeda T, Saruta J, Tsukimura N, Hirota M, Ogawa T. Compromised Epithelial Cell Attachment after Polishing Titanium Surface and Its Restoration by UV Treatment. Materials (Basel) 2020; 13:E3946. [PMID: 32906598 DOI: 10.3390/ma13183946] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 12/22/2022]
Abstract
Titanium-based implant abutments and tissue bars are polished during the finalization. We hypothesized that polishing degrades the bioactivity of titanium, and, if this is the case, photofunctionalization-grade UV treatment can alleviate the adverse effect. Three groups of titanium disks were prepared; machined surface, polished surface and polished surface followed by UV treatment (polished/UV surface). Polishing was performed by the sequential use of greenstone and silicon rubber burs. UV treatment was performed using a UV device for 12 min. Hydrophobicity/hydrophilicity was examined by the contact angle of ddH2O. The surface morphology and chemistry of titanium were examined by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. Human epithelium cells were seeded on titanium disks. The number of cells attached, the spreading behavior of cells and the retention on titanium surfaces were examined. The polished surfaces were smooth with only minor scratches, while the machined surfaces showed traces and metal flashes made by machine-turning. The polished surfaces showed a significantly increased percentage of surface carbon compared to machined surfaces. The carbon percentage on polished/UV surfaces was even lower than that on machined surfaces. A silicon element was detected on polished surfaces but not on polished/UV surfaces. Both machined and polished surfaces were hydrophobic, whereas polished/UV surfaces were hydrophilic. The number of attached cells after 24 h of incubation was 60% lower on polished surfaces than on machined surfaces. The number of attached cells on polished/UV surfaces was even higher than that on machined surfaces. The size and perimeter of cells, which was significantly reduced on polished surfaces, were fully restored on polished/UV surfaces. The number of cells remained adherent after mechanical detachment was reduced to half on polished surfaces compared to machined surfaces. The number of adherent cells on polished/UV surfaces was two times higher than on machined surfaces. In conclusion, polishing titanium causes chemical contamination, while smoothing its surface significantly compromised the attachment and retention of human epithelial cells. The UV treatment of polished titanium surfaces reversed these adverse effects and even outperformed the inherent bioactivity of the original titanium.
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21
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Lee DJ, Kim DY. UV Irradiation-Induced SERS Enhancement in Randomly Distributed Au Nanostructures. Sensors (Basel) 2020; 20:E3842. [PMID: 32660155 PMCID: PMC7411748 DOI: 10.3390/s20143842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/30/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022]
Abstract
Currently used platforms for surface-enhanced Raman scattering (SERS) sensors generally employ metallic nanostructures for enrichment of the plasmonic hotspots in order to provide higher Raman signals, but this procedure is still considered challenging for analyte-surface affinity. This study reports a UV irradiation-induced SERS enhancement that amplifies the interactions between the analytes and metallic surfaces. The UV light can play critical roles in the surface cleaning to improve the SERS signal by removing the impurities from the surfaces and the formation of the negatively charged adsorbed oxygen species on the Au surfaces to enhance the analyte-surface affinity. To evaluate this scenario, we prepared randomly distributed Au nanostructures via thermal annealing with a sputtered Au thin film. The UV light of central wavelength 254 nm was then irradiated on the Au nanostructures for 60 min. The SERS efficiency of the Au nanostructures was subsequently evaluated using rhodamine 6G molecules as the representative Raman probe material. The Raman signal of the Au nanostructures after UV treatment was enhanced by up to approximately 68.7% compared to that of those that did not receive the UV treatment. We expect that the proposed method has the potential to be applied to SERS enhancement with various plasmonic platforms.
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Affiliation(s)
- Dong-Jin Lee
- Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea;
| | - Dae Yu Kim
- Inha Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Korea;
- Department of Electrical Engineering, College of Engineering, Inha University, Incheon 22212, Korea
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22
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Komasa S, Takao S, Yang Y, Zeng Y, Li M, Yan S, Zhang H, Komasa C, Kobayashi Y, Nishizaki H, Nishida H, Kusumoto T, Okazaki J. Effects of UV Treatment on Ceria-Stabilized Zirconia/Alumina Nanocomposite (NANOZR). Materials (Basel) 2020; 13:ma13122772. [PMID: 32570895 PMCID: PMC7345710 DOI: 10.3390/ma13122772] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/08/2020] [Accepted: 06/15/2020] [Indexed: 12/12/2022]
Abstract
Nanostructured zirconia/alumina composite (NANOZR) has been explored as a suitable material for fabricating implants for patients with metal allergy. In this study, we examined the effect of UV treatment on the NANOZR surface. The experimental group was UV-treated NANOZR and the control group was untreated NANOZR. Observation of the surface of the UV-treated materials revealed no mechanical or structural change; however, the carbon content on the material surface was reduced, and the material surface displayed superhydrophilicity. Further, the effects of the UV-induced superhydrophilic properties of NANOZR plates on the adhesion behavior of various cells were investigated. Treatment of the NANOZR surface was found to facilitate protein adsorption onto it. An in vitro evaluation using rat bone marrow cells, human vascular endothelial cells, and rat periodontal ligament cells revealed high levels of adhesion in the experimental group. In addition, it was clarified that the NANOZR surface forms active oxygen and suppresses the generation of oxidative stress. Overall, the study results suggested that UV-treated NANOZR is useful as a new ceramic implant material.
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Affiliation(s)
- Satoshi Komasa
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Seiji Takao
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Yuanyuan Yang
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Yuhao Zeng
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Min Li
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Sifan Yan
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Honghao Zhang
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Chisato Komasa
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
| | - Yasuyuki Kobayashi
- Osaka Research Institute of Industrial Science and Technology, Morinomiya Center, 1-6-50, Morinomiya, Joto-ku, Osaka 536-8553, Japan;
| | - Hiroshi Nishizaki
- Department of Japan, Faculty of Health Sciences, Osaka Dental University, 1-4-4, Makino-honmachi, Hirakata-shi, Osaka 573-1121, Japan; (H.N.); (T.K.)
| | - Hisataka Nishida
- Department of Advanced Hard Materials, The Institute of Scientific and Industrial Research (ISIR), Osaka University, Osaka 567-0047, Japan;
| | - Tetsuji Kusumoto
- Department of Japan, Faculty of Health Sciences, Osaka Dental University, 1-4-4, Makino-honmachi, Hirakata-shi, Osaka 573-1121, Japan; (H.N.); (T.K.)
| | - Joji Okazaki
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1 Kuzuha-hanazono-cho, Hirakata, Osaka 573-1121, Japan; (S.K.); (S.T.); (Y.Y.); (Y.Z.); (M.L.); (S.Y.); (H.Z.); (C.K.)
- Correspondence: ; Tel.: +81-72-864-3084; Fax: +81-72-864-3184
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Hollman J, Dominic JA, Achari G, Langford CH, Tay JH. Effect of UV dose on degradation of venlafaxine using UV/H 2O 2: perspective of augmenting UV units in wastewater treatment. Environ Technol 2020; 41:1107-1116. [PMID: 30188261 DOI: 10.1080/09593330.2018.1521475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 08/28/2018] [Indexed: 06/08/2023]
Abstract
Many water and wastewater treatment plants (WWTPs) are fitted with a UV system that provides post treatment disinfection before the water is released to receiving water. This paper presents a study on expected removal for the pharmaceutical venlafaxine (VEN) in a typical UV unit at a municipal WWTP with analysis of removal rates of an advanced oxidation process using UV irradiation with injection of H2O2. The study is supported by bench scale degradation experiments on VEN. Results demonstrated that UV can completely degrade VEN, but the addition of H2O2 increased pseudo first order rate constant by up to 2.5 times. Extrapolations of the lab data indicated that removal rates of VEN at the UV disinfection unit of a typical municipal WWTP are approximately 0.4% at standard operating conditions. With the addition of 10 mg/L of H2O2, degradation of VEN can be increased by ten times over existing UV treatment. By studying the impact of adjusting parameters such as UV intensity, UV dosage, and H2O2 dosage, a framework is set to allow researchers and engineers to move forward with developing UV/H2O2 systems that meet their future design needs for pharmaceutical removal.
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Affiliation(s)
- Jordan Hollman
- Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Canada
| | - John Albino Dominic
- Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Canada
| | - Gopal Achari
- Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Canada
| | | | - Joo-Hwa Tay
- Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Canada
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Westphal J, Kümmerer K, Olsson O. Experimental and in silico assessment of fate and effects of the UV filter 2-phenylbenzimidazole 5-sulfonic acid and its phototransformation products in aquatic solutions. Water Res 2020; 171:115393. [PMID: 31884378 DOI: 10.1016/j.watres.2019.115393] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 11/19/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Often ingredients of personal care products are present in treated wastewaters, e. g grey water (GW), and are discharged into aquatic systems. Conventional treatment of GW does not fully eliminate micropollutants such as the UV filter substance 2-phenylbenzimidazole-5-sulfonic acid (PBSA). Photolysis has been proposed as an alternative treatment method for other micropollutants, but it is not clear yet whether it can also be used to eliminate PBSA. One goal of this study was to better understand the basic pathways involved in this process. It aimed to identify photo-transformation products (PTPs) by using, in the test conditions, an initial concentration of PBSA higher than those expected in the environment. The photolysis experiments were carried out using Xenon and UV lamps. Under Xenon irradiation only slight primary elimination was found. UV irradiation resulted in almost complete primary elimination of PBSA but not in full mineralization. Four isomeric mono-hydroxylated PTPs were identified by high resolution mass spectrometry (HRMS) which could be confirmed by other studies. A modified luminescent bacteria test (LBT) with Vibrio fischeri was employed to assess acute and chronic toxic effects of the irradiated photolytic mixtures. A strong correlation was found between the kinetics of two of the PTPs and luminescence inhibition indicating bacterial toxicity. Using a set of in silico quantitative structure-activity relationship (QSAR) models, this study also offered new insights concerning the environmental fate and toxicity of the TPs of PBSA as the TPs generated by UV-treatment are more persistent and partly more toxic than PBSA.
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Affiliation(s)
- Janin Westphal
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainablilty, Leuphana University of Lüneburg, Universitätsallee1/C13, DE-21335, Lüneburg, Germany.
| | - Klaus Kümmerer
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainablilty, Leuphana University of Lüneburg, Universitätsallee1/C13, DE-21335, Lüneburg, Germany.
| | - Oliver Olsson
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainablilty, Leuphana University of Lüneburg, Universitätsallee1/C13, DE-21335, Lüneburg, Germany.
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25
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Ao X, Chen Z, Li S, Li C, Lu Z, Sun W. The impact of UV treatment on microbial control and DBPs formation in full-scale drinking water systems in northern China. J Environ Sci (China) 2020; 87:398-410. [PMID: 31791513 DOI: 10.1016/j.jes.2019.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 08/01/2019] [Accepted: 08/01/2019] [Indexed: 06/10/2023]
Abstract
To manage potential microbial risks and meet increasingly strict drinking water health standards, UV treatment has attracted increasing attention for use in drinking water systems in China. However, the effects of UV treatment on microbial control and disinfection by-products (DBPs) formation in real municipal drinking water systems are poorly understood. Here, we collected water samples from three real drinking water systems in Beijing and Tianjin to investigate the impacts of UV treatment on microbial control and DBP formation. We employed heterotrophic plate count (HPC), flow cytometry (FCM), quantitative PCR analysis, and high-throughput sequencing to measure microorganisms in the samples. Different trends were observed between HPC and total cell count (measured by FCM), indicating that a single indicator could not reflect the real degree of biological re-growth in drinking water distribution systems (DWDSs). A significant increase in the 16S rRNA gene concentration was observed when the UV system was stopped. Besides, the bacterial community composition was similar at the phylum level but differed markedly at the genera level among the three DWDSs. Some chlorine-resistant bacteria, including potential pathogens (e.g., Acinetobacter) showed a high relative abundance when the UV system was turned off. It can be concluded that UV treatment can mitigate microbial re-growth to some extent. Finally, UV treatment had a limited influence on the formation of DBPs, including trihalomethanes, haloacetic acids, and nitrogenated DBPs. The findings of this study may help to understand the performance of UV treatment in real drinking water systems.
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Affiliation(s)
- Xiuwei Ao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhongyun Chen
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Simiao Li
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Chen Li
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zedong Lu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China..
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Hatoko M, Komasa S, Zhang H, Sekino T, Okazaki J. UV Treatment Improves the Biocompatibility and Antibacterial Properties of Crystallized Nanostructured Titanium Surface. Int J Mol Sci 2019; 20:ijms20235991. [PMID: 31795108 PMCID: PMC6928612 DOI: 10.3390/ijms20235991] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/21/2019] [Accepted: 11/27/2019] [Indexed: 12/27/2022] Open
Abstract
This study describes the production of a new material composed of pure titanium (Ti) metal with a crystallized nanostructure and investigated whether heat treatment and ultraviolet (UV) irradiation improved its biocompatibility and antibacterial properties. We compared the performance of UV-irradiated and non-irradiated Ti nanosheets (TNS) formed by dark alkaline treatment and heating at 600 °C with that of untreated pure Ti nanostructure (positive control). In vitro and in vivo experiments to assess biocompatibility and effects on cell behavior were performed using human umbilical vein endothelial cells and rat bone marrow cells. The material surface was characterized by X-ray photoelectron spectroscopy (XPS). The antibacterial properties of the irradiated material were evaluated using Staphylococcus aureus, a common pathogenic bacterium. The UV-irradiated TNS exhibited high angiogenic capacity and promoted cell adherence and differentiation relative to the control. Further, surface analysis via XPS revealed a lower C peak for the UV-treated material, indicating a reduced amount of dirt on the material surface. Moreover, UV irradiation decreased the viability of S. aureus on the material surface by stimulating reactive oxygen species production. The biocompatibility and antibacterial properties of the TNS were improved by UV irradiation. Thus, TNS may serve as a useful material for fabrication of dental implants.
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Affiliation(s)
- Mai Hatoko
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata-shi, Osaka 573-1121, Japan; (M.H.); (H.Z.); (J.O.)
| | - Satoshi Komasa
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata-shi, Osaka 573-1121, Japan; (M.H.); (H.Z.); (J.O.)
- Correspondence:
| | - Honghao Zhang
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata-shi, Osaka 573-1121, Japan; (M.H.); (H.Z.); (J.O.)
| | - Tohru Sekino
- The Institute of Scientific and Industrial Research, Osaka University, Suita, Osaka 565-0871, Japan;
| | - Joji Okazaki
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, 8-1, Kuzuhahanazono-cho, Hirakata-shi, Osaka 573-1121, Japan; (M.H.); (H.Z.); (J.O.)
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27
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Jaleh B, Etivand ES, Mohazzab BF, Nasrollahzadeh M, Varma RS. Improving Wettability: Deposition of TiO 2 Nanoparticles on the O 2 Plasma Activated Polypropylene Membrane. Int J Mol Sci 2019; 20:ijms20133309. [PMID: 31284439 PMCID: PMC6651641 DOI: 10.3390/ijms20133309] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 11/29/2022] Open
Abstract
Radio frequency plasma is one of the means to modify the polymer surface namely in the activation of polypropylene membranes (PPM) with O2 plasma. Activated membranes were deposited with TiO2 nanoparticles by the dip coating method and the bare sample and modified sample (PPM5-TiO2) were irradiated by UV lamps for 20–120 min. Characterization techniques such as X-ray diffraction (XRD), Attenuated total reflection technique- Fourier transform infrared spectroscopy (ATR-FTIR), Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM) and water contact angle (WCA) measurements were applied to study the alteration of ensuing membrane surface properties which shows the nanoparticles on the sample surface including the presence of Ti on PPM. The WCA decreased from 135° (PPM) to 90° (PPM5-TiO2) and after UV irradiation, the WCA of PPM5-TiO2 diminished from 90° to 40°.
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Affiliation(s)
- Babak Jaleh
- Department of Physics, Faculty of Science, University of Bu-Ali Sina, Hamedan 65174, Iran.
| | - Ehsan Sabzi Etivand
- Department of Physics, Faculty of Science, University of Bu-Ali Sina, Hamedan 65174, Iran
| | - Bahareh Feizi Mohazzab
- Department of Physics, Faculty of Science, University of Bu-Ali Sina, Hamedan 65174, Iran
| | | | - Rajender S Varma
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
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Sijil PV, Sarada R, Chauhan VS. Enhanced accumulation of alpha-linolenic acid rich lipids in indigenous freshwater microalga Desmodesmus sp.: The effect of low-temperature on nutrient replete, UV treated and nutrient stressed cultures. Bioresour Technol 2019; 273:404-415. [PMID: 30463054 DOI: 10.1016/j.biortech.2018.11.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 06/09/2023]
Abstract
The indigenous microalga, Desmodesmus sp. produced alpha-linolenic acid (ALA) rich lipids in response to low temperature and UV treatment. Incubation at 5 °C showed a 1.5 fold increase in lipid content (34% w/w) with 44% ALA fraction of total fatty acids. The UV treatment (UV 60 min) exhibited a 1.4 fold increase in biomass productivity and 1.6 fold increase in lipid content (37% w/w) with ALA fraction as 31% of total fatty acids. The nitrogen stress enhanced the lipid content (39% w/w) with a reduced ALA fraction (18%) of total fatty acids. The UV treated cultures (UV 40 and 60 min) on incubation at 5 °C showed maximum lipid accumulation (59 to 62% w/w) with ALA fraction of total fatty acids as 39 to 42%. The incubation of nutrient-replete and UV treated cultures at low-temperature could therefore be used for the production of ALA-rich lipids in microalgae.
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Affiliation(s)
- P V Sijil
- Plant Cell Biotechnology (PCBT) Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru - 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201 002, India
| | - R Sarada
- Plant Cell Biotechnology (PCBT) Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru - 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201 002, India
| | - V S Chauhan
- Plant Cell Biotechnology (PCBT) Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru - 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201 002, India.
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29
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Wu CK, Tsai JS, Sung WC. Functional Characteristics of Ultraviolet-Irradiated Tilapia Fish Skin Gelatin. Molecules 2019; 24:molecules24020254. [PMID: 30641905 PMCID: PMC6359145 DOI: 10.3390/molecules24020254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/04/2019] [Accepted: 01/07/2019] [Indexed: 11/16/2022] Open
Abstract
Studies were undertaken to investigate the effects of ultraviolet (UV) irradiation on the gel strength, color, thermal properties, protein molecular masses, and functional groups of commercially available fish gelatin samples. Commercially available tilapia skin gelatin powder was used as the raw material to investigate the functional properties of fish skin gelatin powder treated with UV irradiation for different durations (0⁻6 h). The functional properties of fish gelatin and the optimum irradiation treatment conditions were determined through gel strength testing, color characterization, differential scanning calorimetry, sodium dodecyl sulfate polyacrylamide gel electrophoresis, Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy. UV irradiation treatment increased gel strength and thermal stability, and significantly degraded the macromolecules. FTIR and Raman spectroscopy data indicated that UV irradiation treatment did not significantly change the molecular structure of fish gelatin powder, but these methods could discriminate the molecular structure of gelatin from various sources. Irradiation for 2 h yielded the highest gel strength and melting peak temperature, and the lowest chromatic aberration.
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Affiliation(s)
- Cheng-Kuo Wu
- Department of Food Science, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan.
| | - Jenn-Shou Tsai
- Department of Food Science, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan.
| | - Wen-Chieh Sung
- Department of Food Science, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan.
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Tian M, Thind SS, Dondapati JS, Li X, Chen A. Electrochemical oxidation of 4-chlorophenol for wastewater treatment using highly active UV treated TiO 2 nanotubes. Chemosphere 2018; 209:182-190. [PMID: 29929124 DOI: 10.1016/j.chemosphere.2018.06.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/24/2018] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
In the present work, we report on a facile UV treatment approach for enhancing the electrocatalytic activity of TiO2 nanotubes. The TiO2 nanotubes were prepared using an anodization oxidation method by applying a voltage of 40 V for 8 h in a DMSO + 2% HF solution, and further treated under UV light irradiation. Compared with Pt and untreated TiO2 nanotubes, the UV treated electrode exhibited a superior electrocatalytic activity toward the oxidation of 4-chlorophenol (4-ClPh). The effects of current density and temperature on the electrochemical oxidation of the 4-ClPh were also systematically investigated. The high electrocatalytic activity of the UV treated TiO2 nanotubes was further confirmed by the electrochemical oxidation of other persistent organic pollutants including phenol, 2-, 3-, 4-nitrophenol, and 4-aminophenol. The total organic carbon (TOC) analysis revealed that over 90% 4-ClPh was removed when the UV treated TiO2 electrode was employed and the rate constant was 16 times faster than that of the untreated TiO2 electrode; whereas only 60% 4-ClPh was eliminated at the Pt electrode under the same conditions. This dramatically improved electrocatalytic activity might be attributed to the enhanced donor density, conductivity, and high overpotential for oxygen evolution. Our results demonstrated that the application of the UV treatment to the TiO2 nanotubes enhanced their electrochemical activity and energy consumption efficiency significantly, which is highly desirable for the abatement of persistent organic pollutants.
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Affiliation(s)
- Min Tian
- Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada
| | - Sapanbir S Thind
- Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada
| | - Jesse S Dondapati
- Electrochemical Technology Centre, Department of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario, N1G 2W1, Canada
| | - Xinyong Li
- State Key Laboratory of Fine Chemicals, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Aicheng Chen
- Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada; Electrochemical Technology Centre, Department of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario, N1G 2W1, Canada.
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Lundgreen K, Holbech H, Pedersen KL, Petersen GI, Andreasen RR, George C, Drillet G, Andersen M. UV fluences required for compliance with ballast water discharge standards using two approved methods for algal viability assessment. Mar Pollut Bull 2018; 135:1090-1100. [PMID: 30301006 DOI: 10.1016/j.marpolbul.2018.08.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 06/15/2018] [Accepted: 08/20/2018] [Indexed: 06/08/2023]
Abstract
This study investigates the extra UV fluence needed to meet the International Maritime Organisation's ballast water discharge standards for the 10-50 μm size-class using the approved vital stain (VS) method compared to the Most Probable Number (MPN) method for organism viability assessment. Low- and medium pressure UV collimated beam treatments were applied to natural algae collected in temperate and tropical water environments and analysed using both methods. About 10 times higher UV fluence was required to meet discharge standards when using VS compared to MPN. Implementing a dark-hold period after UV treatments decreased algal viability. Length of dark-hold period to meet discharge standards decreased with increasing UV fluence. No significant differences between temperate and tropical samples were observed. The results showed that UV treated algae assessed using the VS method could meet discharge standards by increasing fluence and/or introducing a dark-hold period.
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Affiliation(s)
- Kim Lundgreen
- Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark.
| | - Henrik Holbech
- Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | | | | | | | - Christaline George
- DHI-NTU Research Centre and Education Hub, 1 CleanTech Loop, #03-05 CleanTech1, 637141, Singapore
| | - Guillaume Drillet
- DHI-NTU Research Centre and Education Hub, 1 CleanTech Loop, #03-05 CleanTech1, 637141, Singapore; SGS-Singapore, 3 Toh Tuck Link, 596228, Singapore(1)
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32
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Li F, Xu M, Ma X, Shen L, Zhu L, Weng Y, Yue G, Tan F, Chen C. UV Treatment of Low-Temperature Processed SnO 2 Electron Transport Layers for Planar Perovskite Solar Cells. Nanoscale Res Lett 2018; 13:216. [PMID: 30030648 PMCID: PMC6054596 DOI: 10.1186/s11671-018-2633-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
We report a new method as UV treatment of low-temperature processed to obtain tin oxide (SnO2) electron transport layers (ETLs). The results show that the high quality of ETLs can be produced by controlling the thickness of the film while it is treated by UV. The thickness is dependent on the concentration of SnO2. Moreover, the conductivity and transmittance of the layer are dependent on the quality of the film. A planar perovskite solar cell is prepared based on this UV-treated film. The temperatures involved in the preparation process are less than 90 °C. An optimal power conversion efficiency of 14.36% is obtained at the concentration of SnO2 of 20%. This method of UV treatment SnO2 film at low temperature is suitable for the low-cost commercialized application.
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Affiliation(s)
- Fumin Li
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Mengqi Xu
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Xingping Ma
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Liang Shen
- State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012 People’s Republic of China
| | - Liangxin Zhu
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Yujuan Weng
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Gentian Yue
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Furui Tan
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
| | - Chong Chen
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
- School of Physics and Electronics, Henan University, 1 Jinming Road, Kaifeng, 475004 People’s Republic of China
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Cruz-González G, Julcour C, Chaumat H, Bourdon V, Ramon-Portugal F, Gaspard S, Jáuregui-Haza UJ, Delmas H. Degradation of chlordecone and beta-hexachlorocyclohexane by photolysis, (photo-)fenton oxidation and ozonation. J Environ Sci Health B 2018; 53:121-125. [PMID: 29148925 DOI: 10.1080/03601234.2017.1388682] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Intensive use of chlorinated pesticides from the 1960s to the 1990s has resulted in a diffuse contamination of soils and surface waters in the banana-producing areas of the French West Indies. The purpose of this research was, for the first time, to examine the degradation of two of these persistent pollutants - chlordecone (CLD) and beta-hexachlorocyclohexane (β-HCH) in 1 mg L-1 synthetic aqueous solutions by means of photolysis, (photo-) Fenton oxidation and ozonation processes. Fenton oxidation is not efficient for CLD and yields less than 15% reduction of β-HCH concentration in 5 h. Conversely, both molecules can be quantitatively converted under UV-Vis irradiation reaching 100% of degradation in 5 h, while combination with hydrogen peroxide and ferrous iron does not show any significant improvement except in high wavelength range (>280 nm). Ozonation exhibits comparable but lower degradation rates than UV processes. Preliminary identification of degradation products indicated that hydrochlordecone was formed during photo-Fenton oxidation of CLD, while for β-HCH the major product peak exhibited C3H3Cl2 as most abundant fragment.
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Affiliation(s)
- Germán Cruz-González
- a Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS , Toulouse , France
- b Instituto Superior de Tecnologías y Ciencias Aplicadas (InSTEC)- Universidad de La Habana , Avenida Salvador Allende No 1110 entre Infanta y Avenida Rancho Boyeros, Quinta de los Molinos, A.P. 6163, La Habana , Cuba
| | - Carine Julcour
- a Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS , Toulouse , France
| | - Hélène Chaumat
- a Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS , Toulouse , France
| | - Valérie Bourdon
- c Service Commun de Spectrométrie de Masse, Université Paul Sabatier , Porte 157, Bâtiment 2R1, 118, route de Narbonne, Toulouse Cedex 09 , France
| | - Felipe Ramon-Portugal
- d UMR CNRS/UPS/ENFA 5174 "Evolution et Diversité Biologique", École National de Formation Agronomique , 2, Route de Narbonne, BP 22687, Auzeville Tolosane, Castanet Cedex , France
| | - Sarra Gaspard
- e Laboratoire COVACHIM M2E, EA 3592, Université des Antilles et de la Guyane , BP 250, Pointe à Pitre Cedex , Guadeloupe
| | - Ulises J Jáuregui-Haza
- b Instituto Superior de Tecnologías y Ciencias Aplicadas (InSTEC)- Universidad de La Habana , Avenida Salvador Allende No 1110 entre Infanta y Avenida Rancho Boyeros, Quinta de los Molinos, A.P. 6163, La Habana , Cuba
| | - Henri Delmas
- a Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS , Toulouse , France
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Shin SH, Choi SY, Lee MH, Nah J. High-Performance Piezoelectric Nanogenerators via Imprinted Sol-Gel BaTiO 3 Nanopillar Array. ACS Appl Mater Interfaces 2017; 9:41099-41103. [PMID: 29130682 DOI: 10.1021/acsami.7b11773] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report high-performance piezoelectric nanogenerators (PENGs) with nanoimprinted sol-gel BaTiO3 (BTO) nanopillar array polarized under high electric field and ultraviolet. The PENGs fabricated using this method demonstrate greatly enhanced output voltage of ∼10 V and current density of ∼1.2 μA cm-2, respectively, in comparison to that of flat PENG. Further, the PENG demonstrates uniform output characteristics over the entire device area thanks to uniform nanoimprint pillar array. The approach introduced here is simple, effective, reliable, and reproducible way to fabricate high-performance sol-gel-based PENGs and electronic devices.
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Affiliation(s)
- Sung-Ho Shin
- Department of Electrical Engineering, Chungnam National University , Daejeon 34134, Korea
| | - Seong-Young Choi
- Department of Applied Chemistry, Kyung Hee University , Yongin, Gyeonggi 17104, Korea
| | - Min Hyung Lee
- Department of Applied Chemistry, Kyung Hee University , Yongin, Gyeonggi 17104, Korea
| | - Junghyo Nah
- Department of Electrical Engineering, Chungnam National University , Daejeon 34134, Korea
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Tribedi P, Dey S. Pre-oxidation of low-density polyethylene (LDPE) by ultraviolet light (UV) promotes enhanced degradation of LDPE in soil. Environ Monit Assess 2017; 189:624. [PMID: 29124475 DOI: 10.1007/s10661-017-6351-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 11/02/2017] [Indexed: 06/07/2023]
Abstract
Polyethylene represents nearly 64% of all the synthetic plastics produced and are mainly used for domestic and industrial applications. Their extensive use poses a serious environmental threat because of their non-biodegradable nature. Among all the polyethylene remediation strategies, in situ bioremediation happens to be the safest and efficient one. In the current study, efforts had been given to compare the extent of LDPE degradation under UV-treated and UV-untreated conditions by soil microcosm. Landfill soil was collected and UV-treated and UV-untreated LDPE were added separately to the soil following incubation under similar conditions. Electron microscopic images as well as the weight loss and the tensile strength results clearly revealed that UV-treated LDPE showed better degradation than the non-treated ones in soil. To elucidate the mechanism of this enhanced biodegradation, the bond spectra of differentially treated LDPE were analyzed by FTIR. The results obtained from bond spectra studies revealed that UV treatment increases both carbonyl and terminal double-bond index of the LDPE, thereby making it highly susceptible for microbial degradation. Moreover, incubation of UV-treated LDPE with soil favors better adherence of metabolically active and significantly higher number of microorganisms on it. Taken together, all these results demonstrate the higher microbial association and their better metabolic potential to the UV-treated LDPE that lead to enhanced degradation of the LDPE by the soil microorganisms.
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Affiliation(s)
- Prosun Tribedi
- Department of Microbiology, Assam Don Bosco University, Tapesia, Sonapur, Assam, 782402, India.
- Department of Biotechnology, The Neotia University, Sarisha, West Bengal, 743363, India.
| | - Samrat Dey
- Department of Physics, Assam Don Bosco University, Azara, Assam, 781017, India
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Zhang H, Komasa S, Mashimo C, Sekino T, Okazaki J. Effect of ultraviolet treatment on bacterial attachment and osteogenic activity to alkali-treated titanium with nanonetwork structures. Int J Nanomedicine 2017; 12:4633-4646. [PMID: 28721040 PMCID: PMC5500560 DOI: 10.2147/ijn.s136273] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Purpose Alkali-treated titanium with nanonetwork structures (TNS) possesses good osteogenic activity; however, the resistance of this material to bacterial contamination remains inadequate. As such, TNS implants are prone to postoperative infection. In this work, we attempted to alter the biological properties of TNS by treatment with short-duration high-intensity ultraviolet (UV) irradiation. Methods TNS discs were treated with UV light (wavelength =254 nm, strength =100 mW/cm2) for 15 minutes using a UV-irradiation machine. We carried out a surface characterization and evaluated the discs for bacterial film formation, protein adsorption, and osteogenic features. Results The superhydrophilicity and surface hydrocarbon elimination exhibited by the treated material (UV-treated titanium with a nanonetwork structure [UV-TNS]) revealed that this treatment effectively changed the surface characteristics of TNS. Notably, UV-TNS also showed reduced colonization by Actinomyces oris during an initial attachment period and inhibition of biofilm formation for up to 6 hours. Moreover, compared to conventional TNS, UV-TNS showed superior osteogenic activity as indicated by increased levels of adhesion, proliferation, alkaline phosphatase activity, osteogenic factor production, and osteogenesis-related gene expression by rat bone marrow mesenchymal stem cells (rBMMSCs). This inverse relationship between bacterial attachment and cell adhesion could be due to the presence of electron–hole pairs induced by high-intensity UV treatment. Conclusion We suggest that simple UV treatment has great clinical potential for TNS implants, as it promotes the osseointegration of the TNS while reducing bacterial contamination, and can be conducted chair-side immediately prior to implantation.
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Affiliation(s)
- Honghao Zhang
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, Hirakata, Osaka, Japan.,Department of Stomatology, Nanfang Hospital and College of Stomatology, Southern Medical University, Guangzhou, Guangdong, China
| | - Satoshi Komasa
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, Hirakata, Osaka, Japan
| | - Chiho Mashimo
- Department of Bacteriology, Osaka Dental University, Hirakata
| | - Tohru Sekino
- The Institute of Scientific and Industrial Research, Osaka University, Suita, Osaka, Japan
| | - Joji Okazaki
- Department of Removable Prosthodontics and Occlusion, Osaka Dental University, Hirakata, Osaka, Japan
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Yibi Y, Chen J, Xue J, Song J, Zeng H. Enhancement of adjustable localized surface plasmon resonance in ZnO nanocrystals via a dual doping approach. Sci Bull (Beijing) 2017; 62:693-699. [PMID: 36659440 DOI: 10.1016/j.scib.2017.04.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/07/2017] [Accepted: 03/31/2017] [Indexed: 01/21/2023]
Abstract
Recently, the localized surface plasmon resonance (LSPR) concept was expanded from noble metals to doped semiconductor nanocrystals (NCs). However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO (IZO) NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation (photo-induced doping). The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films (350Ω/sq) due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy. The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelectronic devices.
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Affiliation(s)
- Yusufkadie Yibi
- Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jiawei Chen
- Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jie Xue
- Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jizhong Song
- Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Haibo Zeng
- Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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Meng Y, Liu G, Liu A, Guo Z, Sun W, Shan F. Photochemical Activation of Electrospun In 2O 3 Nanofibers for High-Performance Electronic Devices. ACS Appl Mater Interfaces 2017; 9:10805-10812. [PMID: 28264156 DOI: 10.1021/acsami.6b15916] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Electrospun metal oxide nanofibers have been regarded as promising blocks for large-area, low-cost, and one-dimensional electronic devices. However, the electronic devices based on electrospun nanofibers usually suffer from poor performance and inferior viability. Here, we report an efficient photochemical process using UV light generated by a high-pressure mercury lamp to promote the electrical performance of the nanofiber-based electronic devices. Such UV treatment can lead to strong photochemical activation of electrospun nanofibers, and therefore, a stable adherent nanofiber network and electronic-clean interface were formed. By use of UV treatment, high-performance indium oxide (In2O3) nanofiber based field-effect transistors (FETs) with highly efficient modulation of electrical characteristics have been successfully fabricated. To reduce the operating voltage and further improve the device performance, the In2O3 nanofiber FETs based on solution-processed high-k AlOx dielectrics were integrated and investigated. The as-fabricated In2O3/AlOx FETs exhibit superior electrical performance, including a high mobility of 19.8 cm2 V-1 s-1, a large on/off current ratio of 106, and high stability over time and cycling. The improved performance of the UV-treated FETs was further confirmed by the integration of the electrospun In2O3/AlOx FETs into inverters. This work presents an important advance toward the practical applications of electrospun nanofibers for functional electronic devices.
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Affiliation(s)
- You Meng
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
| | - Guoxia Liu
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
| | - Ao Liu
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
| | - Zidong Guo
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
| | - Wenjia Sun
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
| | - Fukai Shan
- College of Physics and College of Electronic and Information Engineering, Qingdao University , Qingdao 266071, China
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Jentzsch F, Olsson O, Westphal J, Reich M, Leder C, Kümmerer K. Photodegradation of the UV filter ethylhexyl methoxycinnamate under ultraviolet light: Identification and in silico assessment of photo-transformation products in the context of grey water reuse. Sci Total Environ 2016; 572:1092-1100. [PMID: 27531468 DOI: 10.1016/j.scitotenv.2016.08.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 06/06/2023]
Abstract
To prevent water shortages in the future and to reduce domestic water consumption, decentralized grey water (GW) reuse has become increasingly important. This water has, however, to be free of pollutants. Conventional treatment of GW does not fully eliminate micropollutants such as the UV filter substance ethylhexyl methoxycinnamate (EHMC). EHMC, which is commonly used in sunscreens and personal care products, is an endocrine disruptor and shows potential to bioaccumulation, which is also reflected in its low water solubility. Photolysis has been proposed as an alternative treatment method for other micropollutants, but it is not clear yet whether it can also be used to eliminate EHMC. One goal of this study was to better understand the basic pathways involved in this process. It aimed to identify photo-transformation products (photo-TPs) by using, in the test conditions, an initial concentration of EHMC higher than those expected in the environment. Acetonitrile (ACN) was added in low concentrations to the aqueous solution to overcome the low aquatic solubility of EHMC. The influence of this co-solvent on the degradation kinetics was studied. The photolysis experiments were carried out using a medium pressure mercury lamp, which emits UV light in the range of 200-400nm. The quantum yield of the photolysis of EHMC was 0.0042 and 0.0023mol·Einstein-1 (for 0.2 and 0.5% ACN (v/v), respectively), and the relative and absolute UV photon fluxes were determined. HPLC was used to monitor the elimination kinetics of EHMC, which followed first-order kinetics. The results of LC-MSn analyses revealed that beside others, several oxidized and hydroxylized EHMC isomers were formed as photo-TPs in aqueous solution. Using a set of in silico quantitative structure-activity relationship (QSAR) models, this study also offered new insights concerning the environmental fate and toxicity of the TPs of EHMC.
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Affiliation(s)
- F Jentzsch
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
| | - O Olsson
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
| | - J Westphal
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
| | - M Reich
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
| | - C Leder
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
| | - K Kümmerer
- Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg, Germany.
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Torres Arango MA, Valença de Andrade AS, Cipollone DT, Grant LO, Korakakis D, Sierros KA. Robotic Deposition of TiO2 Films on Flexible Substrates from Hybrid Inks: Investigation of Synthesis-Processing-Microstructure-Photocatalytic Relationships. ACS Appl Mater Interfaces 2016; 8:24659-24670. [PMID: 27568659 DOI: 10.1021/acsami.6b05535] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
TiO2 is an important material widely used in optoelectronic devices due to its semiconducting and photocatalytic properties, nontoxicity, and chemically inert nature. Some indicative applications include water purification systems and energy harvesting. The use of solution, water-based inks for the direct writing of TiO2 on flexible substrates is of paramount importance since it enables low-cost and low-energy intensive large-area manufacturing, compatible with roll-to-roll processing. In this work we study the effect of crystalline TiO2 and polymer addition on the rheological and direct writing properties of Ti-organic/TiO2 inks. We also report on the bridging crystallite formation from the Ti-organic precursor into the TiO2 crystalline phase, under ultraviolet (UV) exposure or mild heat treatments up to 150 °C. Such crystallite formation is found to be enhanced by polymers with strong polarity and pKα such as polyacrylic acid (PAA). X-ray diffraction (XRD) coupled with Raman and X-ray photoelectron (XPS) spectroscopy are used to investigate the crystalline-phase transformation dependence based on the initial TiO2 crystalline-phase concentration and polymer addition. Transmission electron microscopy imaging and selected area electron diffraction patterns confirm the crystalline nature of such bridging printed structures. The obtained inks are patterned on flexible substrates using nozzle-based robotic deposition, a lithography-free, additive manufacturing technique that allows the direct writing of material in specific, digitally predefined, substrate locations. Photocatalytic degradation of methylene blue solutions highlights the potential of the studied films for chemical degradation applications, from low-cost environmentally friendly materials systems.
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Affiliation(s)
- Maria A Torres Arango
- Flexible Electronics for Sustainable Technologies Laboratory (FEST), Department of Mechanical & Aerospace Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
| | - Alana S Valença de Andrade
- Flexible Electronics for Sustainable Technologies Laboratory (FEST), Department of Mechanical & Aerospace Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
| | - Domenic T Cipollone
- Flexible Electronics for Sustainable Technologies Laboratory (FEST), Department of Mechanical & Aerospace Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
| | - Lynnora O Grant
- Flexible Electronics for Sustainable Technologies Laboratory (FEST), Department of Mechanical & Aerospace Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
| | - Dimitris Korakakis
- Material Growth and Characterization Lab, Lane Department of Computer Science and Electrical Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
| | - Konstantinos A Sierros
- Flexible Electronics for Sustainable Technologies Laboratory (FEST), Department of Mechanical & Aerospace Engineering, West Virginia University , 395 Evansdale Drive, Morgantown, West Virginia 26505, United States
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Adapa LM, Azimi Y, Singh S, Porcelli D, Thompson IP. Comparative study of chemical and physical methods for distinguishing between passive and metabolically active mechanisms of water contaminant removal by biofilms. Water Res 2016; 101:574-581. [PMID: 27314554 DOI: 10.1016/j.watres.2016.06.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 05/27/2016] [Accepted: 06/06/2016] [Indexed: 06/06/2023]
Abstract
In this study, physical and chemical approaches were employed to distinguish between passive and active mechanisms in biofilms removing contaminants in waste waters and their relative merits were assessed. Respiration, post-exposure recovery and scanning electron microscopic analysis demonstrated that both ultraviolet (UV) treatment (300 mJ/cm(2)) and sodium azide (10 mM) completely inhibited metabolic activity at 5 and 24 h exposure, respectively, whilst not damaging the integrity of the biofilms. Amongst the commonly used chemical inhibitors, only sodium azide showed complete inhibition after 24 h incubation with only about 10% (±4%) of biofilm carbon released into the bulk solution, compared to 33-41% (±8%) when exposed to 5 mM and 10 mM 2,4-dinitrophenol (DNP) and 69-80% (±5%) when exposed to 2% and 5% w/v formalin, respectively. Biofilm inhibition with UV and sodium azide was found to be equally effective at inhibiting biofilms for treatment of triethanolamine (TEA) and benzotriazole (BTA): the results confirming that the dominant removal mechanism was biodegradation. However, the rates of glucose removal by sodium azide-inhibited biofilms were similar to controls, suggesting that chemical inhibitors were not effective for distinguishing the removal mechanisms of simple sugars. Statistically similar amounts of metal were removed by biofilms treated with UV and sodium azide in zinc, copper and cadmium single-systems: the results indicated that the removal mechanism is predominantly a passive biosorption process.
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Affiliation(s)
- L M Adapa
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom
| | - Y Azimi
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom
| | - S Singh
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom
| | - D Porcelli
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, United Kingdom
| | - I P Thompson
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, United Kingdom.
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Papoutsis K, Vuong QV, Pristijono P, Golding JB, Bowyer MC, Scarlett CJ, Stathopoulos CE. Enhancing the Total Phenolic Content and Antioxidants of Lemon Pomace Aqueous Extracts by Applying UV-C Irradiation to the Dried Powder. Foods 2016; 5:foods5030055. [PMID: 28231150 PMCID: PMC5302404 DOI: 10.3390/foods5030055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/09/2016] [Accepted: 08/19/2016] [Indexed: 01/12/2023] Open
Abstract
Several studies have shown that UV-C (ultraviolet C) irradiation promotes the bioactive compounds and antioxidants of fresh fruits and vegetables. The aim of this study was to apply UV irradiation in dried lemon pomace powder for enhancing its phenolic content and antioxidant properties, thus more bioactive compounds should be available for extraction and utilization. Lemon pomace dried powder was placed under a UV lamp and treated with dosages of 4, 19, 80 and 185 kJ·m−2, while untreated powder was used as a control. UV-C irradiation significantly affected the total phenolic content, total flavonoid content, proanthocyanidins, and antioxidant capacity measured by cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) of the lemon pomace dried powder, while it did not affect the vitamin C content. UV-C irradiation of 19 kJ·m−2 resulted in 19% higher total phenolic content than the control, while UV-C irradiation of 180 kJ·m−2 resulted in 28% higher total flavonoid content than the control. The antioxidant capacity was reduced when UV-C irradiation more than 4 kJ·m−2 was applied. The results of this study indicate that UV-C treatment has the potential to increase the extraction of bioactive compounds of dried lemon pomace at relatively high dosages.
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Affiliation(s)
- Konstantinos Papoutsis
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
| | - Quan V Vuong
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
| | - Penta Pristijono
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
| | - John B Golding
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
- NSW Department of Primary Industries, Locked Bag 26, Gosford 2250, NSW, Australia.
| | - Michael C Bowyer
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
| | - Christopher J Scarlett
- School of Environmental and Life Sciences, The University of Newcastle, P.O. Box 127, Ourimbah 2258, NSW, Australia.
| | - Costas E Stathopoulos
- Division of Food and Drink, School of Science, Engineering and Technology, University of Abertay, Dundee DD1 1HG, UK.
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Altaee N, El-Hiti GA, Fahdil A, Sudesh K, Yousif E. Biodegradation of different formulations of polyhydroxybutyrate films in soil. Springerplus 2016; 5:762. [PMID: 27386248 PMCID: PMC4912537 DOI: 10.1186/s40064-016-2480-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/30/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND Petroleum polymers contribute to non-degradable waste materials and it would therefore be desirable to produce ecofriendly degradable materials. Biodegradation of polyhydroxybutyrate (PHB) in the presence of oligomer hydrolase and PHB depolymerase gave 3-hydroxybutyric acid which could be oxidized to acetyl acetate. Several bacteria and fungi can degrade PHB in the soil. RESULTS Biodegradation of PHB showed a significant decrease in the molecular weight (Mw), number-average molecular weight (Mn) and the dispersity (Mw/Mn) for all the film formulations. Nanofibers of PHB and its composites showed faster degradation compared to other films and displayed complete degradation after 3 weeks. The SEM micrographs showed various surface morphology changes including alterations in appearance of pores, cavity, grooves, incisions, slots and pointers. Such changes were due to the growth of microorganisms that secreted PHB depolymerase enzyme which lead to the biopolymer films degradation. However, PHB nanofibers and its composites films in the presence of TiO2 demonstrated more surface changes with rupture of most nanofibers in which there was a drop in fibres diameter. CONCLUSIONS The degradation of biopolymers help to overcome some of the pollution problems associated with the use of petroleum polymers. PHB nanofiber and its TiO2 composite were degraded faster compared to other PHB film types due to their three dimensional and high surface area structures. The presence of TiO2 nanoparticles in the composite films slowdown the degradation process compared to PHB films. Additionally, the PHB and its composite films that were prepared from UV treated PHB films led to acceleration of the degradation.Graphical abstractBiodegradation of polyhydroxybutyrate films in soil.
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Affiliation(s)
- Nadia Altaee
- />Department of Biotechnology, College of Science, Al-Nahrain University, Baghdad, 10001 Iraq
- />Department of Horticulture and Garden Engineering, College of Agriculture, Al-Qasim Green University, Babil, Al-Qasim 51002 Iraq
| | - Gamal A. El-Hiti
- />Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh, 11433 Saudi Arabia
| | - Ayad Fahdil
- />Department of Biotechnology, College of Science, Al-Nahrain University, Baghdad, 10001 Iraq
| | - Kumar Sudesh
- />School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Emad Yousif
- />Department of Chemistry, College of Science, Al-Nahrain University, Baghdad, 64021 Iraq
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Ben W, Sun P, Huang CH. Effects of combined UV and chlorine treatment on chloroform formation from triclosan. Chemosphere 2016; 150:715-722. [PMID: 26746417 DOI: 10.1016/j.chemosphere.2015.12.071] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 12/16/2015] [Accepted: 12/19/2015] [Indexed: 06/05/2023]
Abstract
The co-exposure to UV irradiation and free chlorine may occur in certain drinking water and wastewater treatment systems. This study investigated the effects of simultaneous low pressure ultraviolet (LPUV) irradiation and free chlorination on the formation of chloroform from triclosan which is a commonly used antibacterial agent. Different treatment systems (i.e., combined UV/chlorine, UV alone, and chlorine alone) were applied to examine the degradation of triclosan and formation of chloroform. The fate of representative intermediates, including chlorinated triclosan, dechlorinated triclosan intermediates and 2,4-dichlorophenol, were tracked to deduce the effect of combined UV/chlorine on the transformation of chloroform formation precursors. The relation between intermediates degradation and chloroform formation was investigated in depth by conducting stepwise experiments with UV and chlorine in different sequences. Results indicate that the combined UV/chlorine notably enhanced the chloroform formation from triclosan. From the reaction mechanism perspective the combined UV/chlorine, where the direct photolysis may play an important role, could accelerate the decay of intermediates and facilitate the generation of productive chloroform precursors. The radicals had modest influence on the degradation of triclosan and intermediates and partly hindered the formation of chloroform. These results emphasize the necessity of considering disinfection by-products formation in the application of combined UV/chlorine technology during water treatment.
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Affiliation(s)
- Weiwei Ben
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332, GA, United States
| | - Peizhe Sun
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332, GA, United States
| | - Ching-Hua Huang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332, GA, United States.
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Li C, Colella NS, Watkins JJ. Low-Temperature Fabrication of Mesoporous Titanium Dioxide Thin Films with Tunable Refractive Indices for One-Dimensional Photonic Crystals and Sensors on Rigid and Flexible Substrates. ACS Appl Mater Interfaces 2015; 7:13180-13188. [PMID: 26023903 DOI: 10.1021/acsami.5b03240] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Highly transparent mesoporous titanium dioxide (TiO2; anatase) thin films were prepared at room temperature via ultraviolet (UV) irradiation of hybrid polymer-TiO2 nanoparticle thin films. This approach utilized a UV-curable polymer in conjunction with the photocatalytic activity of TiO2 to form and degrade the organic component of the composite films in one step, producing films with well-controlled porosity and refractive index. By adjustment of the loading of TiO2 nanoparticles in the host polymer, the refractive index was tuned between 1.53 and 1.73. Facile control of these properties and mild processing conditions was leveraged to fabricate robust one-dimensional photonic crystals (Bragg mirrors) consisting entirely of TiO2 on silicon and flexible poly(ethylene terephthalate) substrates. The mesoporous Bragg mirrors were shown to be effective chemical vapor sensors with strong optical responses.
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Affiliation(s)
- Cheng Li
- Department of Polymer Science and Engineering, University of Massachusetts-Amherst, 120 Governors Drive, Amherst, Massachusetts 01003, United States
| | - Nicholas S Colella
- Department of Polymer Science and Engineering, University of Massachusetts-Amherst, 120 Governors Drive, Amherst, Massachusetts 01003, United States
| | - James J Watkins
- Department of Polymer Science and Engineering, University of Massachusetts-Amherst, 120 Governors Drive, Amherst, Massachusetts 01003, United States
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Majer P, Czégény G, Sándor G, Dix PJ, Hideg E. Antioxidant defence in UV-irradiated tobacco leaves is centred on hydrogen-peroxide neutralization. Plant Physiol Biochem 2014; 82:239-43. [PMID: 25000557 DOI: 10.1016/j.plaphy.2014.06.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 06/17/2014] [Indexed: 06/03/2023]
Abstract
Greenhouse grown tobacco (Nicotiana tabacum L. cv. Petit Havana) plants were exposed to supplemental UV centred at 318 nm and corresponding to 13.6 kJ m(-2) d(-1) biologically effective UV-B (280-315 nm) radiation. After 6 days this treatment decreased photosynthesis by 30%. Leaves responded by a large increase in UV-absorbing pigment content and antioxidant capacities. UV-stimulated defence against ROS was strongest in chloroplasts, since activities of plastid enzymes FeSOD and APX had larger relative increases than other, non-plastid specific SODs or peroxidases. In addition, non-enzymatic defence against hydroxyl radicals was doubled in UV treated leaves as compared to controls. In UV treated leaves, the extent of activation of ROS neutralizing capacities followed a peroxidases > hydroxyl-radical neutralization > SOD order. These results suggest that highly effective hydrogen peroxide neutralization is the focal point of surviving UV-inducible oxidative stress and argue against a direct signalling role of hydrogen peroxide in maintaining adaptation to UV, at least in laboratory experiments.
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Affiliation(s)
- Petra Majer
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Gyula Czégény
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary; Department of Plant Biology, Institute of Biology, University of Pécs, Pécs, Hungary
| | - Györgyi Sándor
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Philip J Dix
- Biology Department, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Eva Hideg
- Department of Plant Biology, Institute of Biology, University of Pécs, Pécs, Hungary.
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Schröder M, Sallard S, Böhm M, Einert M, Suchomski C, Smarsly BM, Mutisya S, Bertino MF. An all low-temperature fabrication of macroporous, electrochemically addressable anatase thin films. Small 2014; 10:1566-1442. [PMID: 24644269 DOI: 10.1002/smll.201300970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 08/26/2013] [Indexed: 06/03/2023]
Abstract
Macroporous TiO₂ (anatase) thin films are fabricated by an all low-temperature process in which substrates are dip-coated in suspensions of mixed anatase nanoparticles and polystyrene beads, and the templating agents are removed by ultraviolet (UV) irradiation at a temperature below 50 °C. Scanning electron microscopy (SEM) and Raman spectroscopy show that the templating polymer beads are removed by UV irradiation combined with the photocatalytic activity of TiO₂. X-Ray diffraction reveals that nanoparticle growth is negligible in UV irradiated films, while nanoparticle size increases by almost 10 times in calcined films that are prepared for comparison. The macroporous films are prepared on FTO-(fluorine-doped tin oxide) coated glass and ITO (indium tin oxide) coated flexible plastics and thereby used as working electrodes. In both cases, the films are electrochemically addressable, and cyclic voltammetry is consistent with the response of bulk TiO₂ for calcined films and of nanoscale-TiO₂ for UV-irradiated films.
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Affiliation(s)
- Michael Schröder
- Justus-Liebig-Universität, Institute of Physical-Chemistry, Heinrich-Buff-Ring 58, D-35392, Giessen, Germany
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Collado N, Rodriguez-Mozaz S, Gros M, Rubirola A, Barceló D, Comas J, Rodriguez-Roda I, Buttiglieri G. Pharmaceuticals occurrence in a WWTP with significant industrial contribution and its input into the river system. Environ Pollut 2014; 185:202-12. [PMID: 24286695 DOI: 10.1016/j.envpol.2013.10.040] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 10/25/2013] [Accepted: 10/31/2013] [Indexed: 05/07/2023]
Abstract
Occurrence and removal of 81 representative Pharmaceutical Active Compounds (PhACs) were assessed in a municipal WWTP located in a highly industrialized area, with partial water reuse after UV tertiary treatment and discharge to a Mediterranean river. Water monitoring was performed in an integrated way at different points in the WWTP and river along three seasons. Consistent differences between therapeutic classes were observed in terms of influent concentration, removal efficiencies and seasonal variation. Conventional (primary and secondary) treatment was unable to completely remove numerous compounds and UV-based tertiary treatment played a complementary role for some of them. Industrial activity influence was highlighted in terms of PhACs presence and seasonal distribution. Even if global WWTP effluent impact on the studied river appeared to be minor, PhACs resulted widespread pollutants in river waters. Contamination can be particularly critical in summer in water scarcity areas, when water flow decreases considerably.
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Affiliation(s)
- N Collado
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - S Rodriguez-Mozaz
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain
| | - M Gros
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain
| | - A Rubirola
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain
| | - D Barceló
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain; Water and Soil Quality Research Group, Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - J Comas
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - I Rodriguez-Roda
- LEQUiA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain; Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain
| | - G Buttiglieri
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
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