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Xu T, Li X, Wu C, Fan G, Li T, Zhou D, Zhu J, Wu Z, Hua X. Improved encapsulation effect and structural properties of whey protein isolate by dielectric barrier discharge cold plasma. Int J Biol Macromol 2024; 257:128556. [PMID: 38061529 DOI: 10.1016/j.ijbiomac.2023.128556] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/23/2023] [Accepted: 11/30/2023] [Indexed: 12/22/2023]
Abstract
The whey protein isolate (WPI) was modified by dielectric barrier discharge cold plasma (DBD) in order to improve its encapsulation efficiency of rutin. In this work, the effect of DBD treatment on structure and physicochemical properties of WPI and the interaction between DBD-treated WPI and rutin were investigated. The results showed that the structural change of WPI leaded to the exposure of internal hydrophobic groups, increasing the interaction site with rutin. The encapsulation efficiency of DBD-treated WPI (30 kV, 30 s) on rutin was improved by 12.42 % compared with control group. The results of multispectral analysis showed that static quenching occurred in the process of interaction between DBD-treated and rutin, hydrogen bond and van der Waals force were the main forces between them. Therefore, DBD treatment can be used as a method to improve the encapsulation efficiency of WPI on hydrophobic active substances.
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Affiliation(s)
- Ting Xu
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Xiaojing Li
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
| | - Caie Wu
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
| | - Gongjian Fan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
| | - Tingting Li
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
| | - Dandan Zhou
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
| | - Jinpeng Zhu
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Zhihao Wu
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Xiaowen Hua
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201 Ningbo, China
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Liu M, Feng J, Yang X, Yu B, Zhuang J, Xu H, Xiang Q, Ma R, Jiao Z. Recent advances in the degradation efficacy and mechanisms of mycotoxins in food by atmospheric cold plasma. Ecotoxicol Environ Saf 2024; 270:115944. [PMID: 38184978 DOI: 10.1016/j.ecoenv.2024.115944] [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: 08/28/2023] [Revised: 12/17/2023] [Accepted: 01/03/2024] [Indexed: 01/09/2024]
Abstract
Food contaminated by mycotoxins has become a worldwide public problem with political and economic implications. Although a variety of traditional methods have been used to eliminate mycotoxins from agri-foods, the results have been somewhat less than satisfactory. As an emerging non-thermal processing technology, atmospheric cold plasma (ACP) has great potential for food decontamination. Herein, this review mainly presents the degradation efficiency of ACP on mycotoxins in vitro and agri-foods as well as its possible degradation mechanisms. Meanwhile, ACP effects on food quality, factors affecting the degradation efficiency and the toxicity of degradation products are also discussed. According to the literatures, ACP could efficiently degrade many mycotoxins (e.g., aflatoxin, deoxynivalenol, zearalenone, ochratoxin A, fumonisin, and T-2 toxin) both in vitro and various foods (e.g., hazelnut, peanut, maize, rice, wheat, barley, oat flour, and date palm fruit) with little effects on the nutritional and sensory properties of food. The degradation efficacy was dependent on many factors including ACP treatment parameter, working gas, mycotoxin property, and food substrate. The mycotoxin degradation by ACP was mainly attributed to the reactive oxygen and nitrogen species in ACP, which can damage the chemical bonds of mycotoxins, consequently reducing the toxicity of mycotoxins.
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Affiliation(s)
- Mengjie Liu
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; Henan Key Laboratory of Ion-beam Bioengineering, Zhengzhou University, Zhengzhou 450052, China
| | - Junxia Feng
- Huadu District People's Hospital of Guangzhou, Guangzhou 510800, China
| | - Xudong Yang
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; Henan Key Laboratory of Ion-beam Bioengineering, Zhengzhou University, Zhengzhou 450052, China
| | - Bo Yu
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Jie Zhuang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Hangbo Xu
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; Henan Key Laboratory of Ion-beam Bioengineering, Zhengzhou University, Zhengzhou 450052, China
| | - Qisen Xiang
- College of Food and Bioengineering, Zhengzhou University of Light Industry, Zhengzhou 450001, China.
| | - Ruonan Ma
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; Henan Key Laboratory of Ion-beam Bioengineering, Zhengzhou University, Zhengzhou 450052, China.
| | - Zhen Jiao
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; Henan Key Laboratory of Ion-beam Bioengineering, Zhengzhou University, Zhengzhou 450052, China
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3
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Chen Y, Chen Y, Fang Y, Pei Z, Zhang W. Coconut milk treated by atmospheric cold plasma: Effect on quality and stability. Food Chem 2024; 430:137045. [PMID: 37541035 DOI: 10.1016/j.foodchem.2023.137045] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 03/08/2023] [Revised: 07/04/2023] [Accepted: 07/26/2023] [Indexed: 08/06/2023]
Abstract
Commercial sterilization plays an important role in extending the shelf-life of coconut milk. However, thermal sterilization affects the quality of coconut milk. This study was initiated to evaluate the effects of atmospheric cold plasma (ACP) treatment on some important quality parameters of coconut milk. ACP treatment had a slight effect on physicochemical characteristics and nutritional ingredients while it obviously reduced the colony count. Furthermore, ACP treatment obviously promoted the formation of lactone, an indispensable volatile substance in coconut milk. Insufficient or moderate ACP treatment had subtle effect on the sensory quality. Notably, moderate ACP treatment reduced the droplet size from 28.0 μm to 18.6 μm, and improved the stability during storage and centrifugation, especially at 60 kV 60 s. Overall, sterilization of coconut milk by ACP at 60 kV 60 s was the most ideal. This study can provide theoretical guidance for the application of ACP in liquid food.
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Affiliation(s)
- Yang Chen
- School of Food Science and Engineering, Hainan University, Hainan 570228, China
| | - Yile Chen
- School of Food Science and Engineering, Hainan University, Hainan 570228, China
| | - Yajing Fang
- School of Food Science and Engineering, Hainan University, Hainan 570228, China
| | - Zhisheng Pei
- School of Food Science and Engineering, Hainan University, Hainan 570228, China; School of Food Science and Engineering, Hainan Tropical Ocean University, Sanya 572022, China
| | - Weimin Zhang
- School of Food Science and Engineering, Hainan University, Hainan 570228, China.
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Hu J, Huang W, Wang Y, Jin J, Li Y, Chen J, Zheng Y, Deng S. Atmospheric cold plasma: A potential technology to control Shewanella putrefaciens in stored shrimp. Int J Food Microbiol 2023; 390:110127. [PMID: 36806858 DOI: 10.1016/j.ijfoodmicro.2023.110127] [Citation(s) in RCA: 2] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 02/04/2023] [Accepted: 02/07/2023] [Indexed: 02/12/2023]
Abstract
This work aimed to investigate the inactivation mechanism of atmospheric cold plasma (ACP) against Shewanella putrefaciens both in PBS and sterile shrimp juice (SSJ). Reductions in cell density, cell viability, and biofilm formation activity were observed after ACP treatment. ACP cyclical treatment (1 min, 5 times) was more efficient than a one-time treatment (5 min, 1 time). After ACP cyclical treatment, the cell counts and cell viability of S. putrefaciens in PBS were decreased by 3.41 log CFU/mL and 85.30 %, respectively. As for SSJ group, the antibacterial efficiency of ACP declined, but the antibacterial effect of ACP cyclical treatment was still stronger than that of ACP one-time treatment. The biofilm formation activity of S. putrefaciens in PBS was almost completely inhibited, while it gradually returned to normal level with the prolonged of storage time for the SSJ counterpart. The rapid decrease in AKP activity after ACP treatment indicated the damage to cell wall integrity, which was also demonstrated by TEM. In addition, cell membrane and DNA damage of the strain also occurred after ACP treatment. The ROS fluorescence intensity in PBS was higher for the one-time treatment group, while the cyclical treatment group exhibited higher and more stable ozone levels. It was also detected that the total nitric oxide concentration in bacterial suspension depended on the dose of ACP treatment time. ACP treatment (35 kV) for 5 min, especially cyclical treatment, displayed its antibacterial properties on packaged shrimp contaminated with high concentration of S. putrefaciens. ACP cyclical treatment reduced surface bacterial counts of whole shrimps by 0.52 log CFU/mL, while ACP one-time treatment only achieved a decrease of 0.18 log CFU/mL. Therefore, ACP treatment could be considered as a potential alternative to enhance microbial control in food processing.
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Affiliation(s)
- Jiajie Hu
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Weijiao Huang
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Yihong Wang
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Jing Jin
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Yuwei Li
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Jing Chen
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China.
| | - Yan Zheng
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China
| | - Shanggui Deng
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China
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Zhu Y, Elliot M, Zheng Y, Chen J, Chen D, Deng S. Aggregation and conformational change of mushroom (Agaricus bisporus) polyphenol oxidase subjected to atmospheric cold plasma treatment. Food Chem 2022; 386:132707. [PMID: 35339091 DOI: 10.1016/j.foodchem.2022.132707] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 03/10/2022] [Accepted: 03/12/2022] [Indexed: 11/25/2022]
Abstract
Atmospheric cold plasma (ACP) is a novel nonthermal technology with potential applications in maintaining and improving food quality. The effect of ACP on the activity and structure of mushroom (Agaricus bisporus) polyphenol oxidase (PPO) was evaluated. Results demonstrated that the dielectric barrier discharge (DBD) based plasma technology could inactivate PPO (up to 69%) at 50 kV with the increased concentrations of H2O2 and NOx. An obvious enhancement of surface hydrophobicity was observed, whereas a gradual reduction of total sulfhydryl content was recorded with the increasing exposure time. Data from circular dichroism, atomic force microscopy, particle size distribution and fluorescence spectra displayed the rearrangement of secondary structure and disruption of the tertiary structure. Red shifts of fluorescence spectra showed positive correlations with the inactivation rate of PPO. Therefore, ACP treatment could be served as an alternative approach to inactivate undesirable enzymes to minimize the loss of food nutrition and quality.
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Affiliation(s)
- Yifan Zhu
- College of Food and Medicine, Zhejiang Ocean University, Zhoushan 316022, China
| | - Mubango Elliot
- College of Food Science and Nutrition Engineering, China Agricultural University, Beijing 100083, China
| | - Yanhong Zheng
- College of Food and Medicine, Zhejiang Ocean University, Zhoushan 316022, China
| | - Jing Chen
- College of Food and Medicine, Zhejiang Ocean University, Zhoushan 316022, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, Zhoushan 316022, China.
| | - Dongzhi Chen
- School of Petrochemical Engineering & Environment, Zhejiang Ocean University, Zhoushan 316022, China
| | - Shanggui Deng
- College of Food and Medicine, Zhejiang Ocean University, Zhoushan 316022, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, Zhoushan 316022, China
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Lin SP, Huang SH, Ting Y, Hsu HY, Cheng KC. Evaluation of detoxified sugarcane bagasse hydrolysate by atmospheric cold plasma for bacterial cellulose production. Int J Biol Macromol 2022; 204:136-43. [PMID: 35120944 DOI: 10.1016/j.ijbiomac.2022.01.186] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 11/23/2022]
Abstract
Cellulosic waste as a major type of agricultural waste can be acid deconstructed as a carbon source for fermentation application. However, various fermented inhibitors, such as formic acid, furfural, and 5-hydroxymethylfurfural, are also produced during processing. In this study, sugarcane bagasse (SB) was hydrolyzed with sulfuric acid, and atmospheric cold plasma (ACP) was used to remove the toxic inhibitors. The detoxified SB hydrolysate was used as alternative nutrients for bacterial cellulose (BC) production. Results showed that degradation rates of formic acid, 5-hydroxymethylfurfural, and furfural respectively reached 25.2%, 78.6%, and 100% with optimized ACP conditions (argon ACP at 200 W for 25 min). In BC production, the ACP-treated SB hydrolysate group (PT) exhibited high BC production (1.68 g/L) but was lower than that from the ACP-untreated SB hydrolysate group (PUT) (1.88 g/L), which suggests that ACP detoxification might also cause some crucial nutrients loss of the SB hydrolysate, leading to a decrease in BC production. The material properties of BC produced from detoxified based medium are also evaluated. These findings have important implications for the broader domain of ACP detoxification for cellulosic acid hydrolysates applied to BC production.
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Elliot M, Chen J, Chen DZ, Hu XM, Ekaterina N, Deng SG. Effects of a cold plasma-assisted shrimp processing chain on biochemical and sensory quality alterations in Pacific white shrimps ( Penaeus vannamei). FOOD SCI TECHNOL INT 2021; 28:683-693. [PMID: 34726105 DOI: 10.1177/10820132211050847] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In this paper, remodeling the shrimp processing chain and the effects of the transformation on the biochemical and sensory qualities of fresh Pacific white shrimp (Penaeus vannamei) under refrigeration storage were investigated. In the proposed model, a dielectric barrier discharge atmospheric cold plasma pretreatment step using a 60 kV source for 60, 90, 120, and 150 s was introduced after the first and second wash followed by refrigeration storage at 4 ± 1 °C for 12 days. Chemical, biochemical, and sensory attributes of the shrimp were monitored and compared with those of shrimp processed through the traditional method without atmospheric cold plasma pretreatment (control). Incorporating minimal dielectric barrier discharge atmospheric cold plasma pretreatment step had more desirable quality outcomes characterized by low malondialdehyde concentration, low volatile nitrogen products content, and comparable proximate composition. Texture, pH, and color were remarkably retained at 120 and 150 s of atmospheric cold plasma pretreatment and protein degradation was negligible up to 90 s than at 120 and 150 s of pretreatment. We conclude that remodeling the shrimp processing chain through incorporating minimal dielectric barrier discharge atmospheric cold plasma pretreatment with key considerations on operation parameters can maximize the beneficial biochemical and sensory quality outcomes while minimizing the negative impacts associated with traditional shrimp processing.
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Affiliation(s)
- Mubango Elliot
- College of Food Science and Pharmacy, 71233Zhejiang Ocean University, China
| | - Jing Chen
- College of Food Science and Pharmacy, 71233Zhejiang Ocean University, China.,Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, China
| | - Dong-Zhi Chen
- School of Petrochemical Engineering and environment, 71233Zhejiang Ocean University, China
| | - Xiao-Meng Hu
- College of Food Science and Pharmacy, 71233Zhejiang Ocean University, China
| | | | - Shang-Gui Deng
- College of Food Science and Pharmacy, 71233Zhejiang Ocean University, China.,Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, China
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Wang X, Wang Z, Zhuang H, Nasiru MM, Yuan Y, Zhang J, Yan W. Changes in color, myoglobin, and lipid oxidation in beef patties treated by dielectric barrier discharge cold plasma during storage. Meat Sci 2021; 176:108456. [PMID: 33621829 DOI: 10.1016/j.meatsci.2021.108456] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [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: 08/19/2020] [Revised: 12/15/2020] [Accepted: 02/04/2021] [Indexed: 12/01/2022]
Abstract
The objective of this work was to investigate the changes in color, metmyoglobin reducing activity (MRA), and lipid oxidation (TBARS) and their relationships in beef patties treated by dielectric barrier discharge cold plasma (DBD-CP) at different voltages and frequencies during storage at 4 °C. DBD-CP treatment, including treatment voltages and frequencies, caused the decrease of a⁎ value and MRA (P < 0.05), promoted the accumulation of metmyoglobin (P < 0.05), and significantly increased TBARS values (P < 0.05). It was the first time revealed that the effect of treatment voltage on the quality of beef patty was greater than that of frequency. In addition, there were significant and strong positive correlations between a⁎ value and MRA and negative correlations between a⁎ value, metmyoglobin (MMb)% and TBARS. Taken together, Data demonstrated that DBD-CP treatment can significantly affect meat redness, Mb contents, MRA, and lipid oxidation in ground beef during storage, and accelerate discoloration and lipid oxidation of meat.
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Affiliation(s)
- Xiaoting Wang
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
| | - Zhaobin Wang
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
| | - Hong Zhuang
- Quality and Safety Assessment Research Unit, U.S. National Poultry Research Center, USDA-ARS, 950 College Station Road, Athens, GA 30605, United States.
| | - Mustapha Muhammad Nasiru
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
| | - Yuan Yuan
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
| | - Jianhao Zhang
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
| | - Wenjing Yan
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
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Santoso SP, Lin SP, Wang TY, Ting Y, Hsieh CW, Yu RC, Angkawijaya AE, Soetaredjo FE, Hsu HY, Cheng KC. Atmospheric cold plasma-assisted pineapple peel waste hydrolysate detoxification for the production of bacterial cellulose. Int J Biol Macromol 2021; 175:526-534. [PMID: 33524483 DOI: 10.1016/j.ijbiomac.2021.01.169] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 01/01/2023]
Abstract
Toxic compounds in pineapple peel waste hydrolysate (PPWH), namely formic acid, 5-hydroxymethylfurfural (HMF), and furfural, are the major predicament in its utilization as a carbon source for bacterial cellulose (BC) fermentation. A rapid detoxification procedures using atmospheric cold plasma (ACP) technique were employed to reduce the toxic compounds. ACP treatment allows the breakdown of toxic compounds without causing excessive breakdown of sugars. Herein, the performance of two available laboratory ACP reactors for PPWH detoxification was being demonstrated. ACP-reactor-1 (R1) runs on plasma power of 80-200 W with argon (Ar) plasma source, while ACP-reactor-2 (R2) runs at 500-600 W with air plasma source. Treatment in R1, at 200 W for 15 min, results in 74.06%, 51.38%, and 21.81% reduction of furfural, HMF, and formic acid. Treatment in R2 at 600 W gives 45.05%, 32.59%, and 60.41% reductions of furfural, HMF, and formic acid. The BC yield from the fermentation of Komagateibacter xylinus in the R1-treated PPWH, R2-treated PPWH, and untreated-PPWH is 2.82, 3.82, and 2.97 g/L, respectively. The results show that ACP treatment provides a novel detoxified strategy in achieving agricultural waste hydrolysate reuse in fermentation. Furthermore, the results also imply that untreated PPWH can be an inexpensive and sustainable resource for fermentation media supplementation.
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Affiliation(s)
- Shella Permatasari Santoso
- Chemical Engineering Department, Widya Mandala Surabaya Catholic University, #37, Kalijudan Rd., Surabaya 60114, East Java, Indonesia; Chemical Engineering Department, National Taiwan University of Science and Technology, #43, Sec. 4, Keelung Rd., Taipei 10607, Taiwan
| | - Shin-Ping Lin
- School of Food Safety, Taipei Medical University, #250, Wuxing Street, Xinyi Dist., Taipei 11042, Taiwan
| | - Tan-Ying Wang
- Institute of Food Science and Technology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan; Institute of Biotechnology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Yuwen Ting
- Institute of Food Science and Technology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Chang-Wei Hsieh
- Department of Food Science and Biotechnology, National Chung Hsing University, 145 Xingda Rd., South Dist., Taichung 40227, Taiwan
| | - Roch-Chui Yu
- Institute of Food Science and Technology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Artik Elisa Angkawijaya
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, #43, Sec. 4, Keelung Rd., Taipei 10607, Taiwan
| | - Felycia Edi Soetaredjo
- Chemical Engineering Department, Widya Mandala Surabaya Catholic University, #37, Kalijudan Rd., Surabaya 60114, East Java, Indonesia; Chemical Engineering Department, National Taiwan University of Science and Technology, #43, Sec. 4, Keelung Rd., Taipei 10607, Taiwan
| | - Hsien-Yi Hsu
- School of Energy and Environment & Department of Materials Science and Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong, China; Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China
| | - Kuan-Chen Cheng
- Institute of Food Science and Technology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan; Institute of Biotechnology, National Taiwan University, #1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, 91, Hsueh-Shih Road, Taichung 40402, Taiwan; Department of Optometry, Asia University, 500, Lioufeng Rd., Wufeng, Taichung 41354, Taiwan.
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Tolouie H, Mohammadifar MA, Ghomi H, Hashemi M. Argon and nitrogen cold plasma effects on wheat germ lipolytic enzymes: Comparison to thermal treatment. Food Chem 2020; 346:128974. [PMID: 33465571 DOI: 10.1016/j.foodchem.2020.128974] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 03/31/2020] [Revised: 12/13/2020] [Accepted: 12/28/2020] [Indexed: 01/08/2023]
Abstract
The effects of argon and nitrogen cold plasma treatments on the lipolytic enzymes activity in wheat germ were investigated. Using argon as plasma gas, the residual activity of lipase and lipoxygenase decreased to 42.50% and 87.72%, respectively after 30 min. Switching plasma input gas to nitrogen, the residual activities of lipase and lipoxygenase after the same time of atmospheric cold plasma (ACP) treatment were 77.50% and 92.52%, respectively. The antioxidant potential and phenolic compounds show no significant difference during ACP duration. However, the remaining activities of lipase and lipoxygenase after 30 min steam autoclaving were 6.25% and 18.60%, respectively. Also, the antioxidant activity and total phenolic content reduced by 14.70% and 30.80%, respectively. In brief, the ACP treatment efficiency was function of the input gas and the treatment time. The presented results about the input gas impacts would be useful in industrial development of ACP application for wheat germ stabilization.
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Affiliation(s)
- Haniye Tolouie
- Department of Food Science and Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Amin Mohammadifar
- Research Group for Food Production Engineering, National Food Institute, Technical University of Denmark, SøltoftsPlads, 2800 Kgs. Lyngby, Denmark.
| | - Hamid Ghomi
- Laser and Plasma Research Institute, Shahid Beheshti University, Evin, 1983963113 Tehran, Iran.
| | - Maryam Hashemi
- Microbial Biotechnology Department, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.
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11
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Ng SW, Lu P, Rulikowska A, Boehm D, O'Neill G, Bourke P. The effect of atmospheric cold plasma treatment on the antigenic properties of bovine milk casein and whey proteins. Food Chem 2020; 342:128283. [PMID: 33067041 DOI: 10.1016/j.foodchem.2020.128283] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 09/29/2020] [Accepted: 09/29/2020] [Indexed: 10/23/2022]
Abstract
Casein, β-lactoglobulin and α-lactalbumin are major milk protein allergens. In the present study, the structural modifications and antigenic response of these bovine milk allergens as induced by non-thermal treatment by atmospheric cold plasma were investigated. Spark discharge (SD) and glow discharge (GD), as previously characterized cold plasma systems, were used for protein treatments. Casein, β-lactoglobulin and α-lactalbumin were analyzed before and after plasma treatment using SDS-PAGE, FTIR, UPLC-MS/MS and ELISA. SDS-PAGE results revealed a reduction in the casein and α-lactalbumin intensity bands after SD or GD treatments; however, the β-lactoglobulin intensity band remained unchanged. FTIR studies revealed alterations in protein secondary structure induced by plasma, particularly contents of β-sheet and β-turn. The UPLC-MS/MS results showed that the amino acid compositions decreased after plasma treatments. ELISA of casein and α-lactalbumin showed a decrease in antigenicity post plasma treatment, whereas ELISA of β-lactoglobulin showed an increase in antigenicity. The study indicates that atmospheric cold plasma can be tailored to mitigate the risk of bovine milk allergens in the dairy processing and ingredients sectors.
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Affiliation(s)
- Sing Wei Ng
- Plasma Research Group, School of Biosystems and Food Engineering, University College Dublin, Dublin 4, Ireland; Environmental Sustainability and Health Institute, Technological University Dublin, Dublin 7, Ireland
| | - Peng Lu
- Plasma Research Group, School of Biosystems and Food Engineering, University College Dublin, Dublin 4, Ireland
| | - Aleksandra Rulikowska
- Environmental Sustainability and Health Institute, Technological University Dublin, Dublin 7, Ireland
| | - Daniela Boehm
- Environmental Sustainability and Health Institute, Technological University Dublin, Dublin 7, Ireland
| | - Graham O'Neill
- Environmental Sustainability and Health Institute, Technological University Dublin, Dublin 7, Ireland
| | - Paula Bourke
- Plasma Research Group, School of Biosystems and Food Engineering, University College Dublin, Dublin 4, Ireland; Environmental Sustainability and Health Institute, Technological University Dublin, Dublin 7, Ireland; Institute for Global Food Security, School of Biological Sciences, Queens University Belfast, Northern Ireland, United Kingdom.
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12
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Los A, Ziuzina D, Boehm D, Bourke P. Effects of cold plasma on wheat grain microbiome and antimicrobial efficacy against challenge pathogens and their resistance. Int J Food Microbiol 2020; 335:108889. [PMID: 33007604 DOI: 10.1016/j.ijfoodmicro.2020.108889] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 08/31/2020] [Accepted: 09/06/2020] [Indexed: 12/31/2022]
Abstract
The safety and quality of cereal grain supplies are adversely impacted by microbiological contamination, with novel interventions required to maximise whole grains safety and stability. The microbiological contaminants of wheat grains and the efficacy of Atmospheric Cold Plasma (ACP) for potential to control these risks were investigated. The evaluations were performed using a contained reactor dielectric barrier discharge (DBD) system; samples were treated for 0-20 min using direct and indirect plasma exposure. Amplicon-based metagenomic analysis using bacterial 16S rRNA gene and fungal 18S rRNA gene with internal transcribed spacer (ITS) region was performed to characterize the change in microbial community composition in response to ACP treatment. The antimicrobial efficacy of ACP against a range of bacterial and fungal contaminants of wheat, was assessed to include individual isolates from grains as challenge pathogens. ACP influenced wheat microbiome composition, with a higher microbial diversity as well as abundance found on the untreated control grain samples. Culture and genomic approaches revealed different trends for mycoflora detection and control. A challenge study demonstrated that using direct mode of plasma exposure with 20 min of treatment significantly reduced the concentration of all pathogens. Overall, reduction levels for B. atrophaeus vegetative cells were higher than for all fungal species tested, whereas B. atrophaeus spores were the most resistant to ACP among all microorganisms tested. Of note, repeating sub-lethal plasma treatment did not induce resistance to ACP in either B. atrophaeus or A. flavus spores. ACP process control could be tailored to address diverse microbiological risks for grain stability and safety.
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13
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Dong S, Guo P, Chen GY, Jin N, Chen Y. Study on the atmospheric cold plasma (ACP) treatment of zein film: Surface properties and cytocompatibility. Int J Biol Macromol 2020; 153:1319-1327. [PMID: 31756479 DOI: 10.1016/j.ijbiomac.2019.10.268] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 07/30/2019] [Revised: 10/12/2019] [Accepted: 10/28/2019] [Indexed: 01/02/2023]
Abstract
The cell adhesion and proliferation of zein-based biomaterials in cell culture application are limited by the strong hydrophobic surface with low surface energy. In this study, atmospheric cold plasma (ACP) was developed as a modification approach in enhancing the surface hydrophilic and cytocompatibility of zein films. The results indicated that water contact angles decreased from 72.85° (untreated) to 47.43° under the voltage of 100 V. The improvement of the surface free energy (SFE) was mainly attributed to the polar component rather than dispersive component. X-ray photoelectron spectroscopy (XPS) results indicated the change of surface physicochemical properties was mainly due to the partially transformation of long-chain aliphatic hydrocarbons (CH and/or CC) to oxygen- and nitrogen-containing bonds (CO, CO and CN). Furthermore, the content of secondary structure demonstrated β-turn and α-helix were transformed into β-sheet and random coil after ACP treatment. Combining with the cell experiment results, plasma treatment could significantly improve the adhesion rate and proliferation activity of C2C12 cells on zein films. With better cytocompatibility, the potentials of zein in tissue engineering scaffold could be readily exploited.
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Affiliation(s)
- Shuang Dong
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China
| | - Peng Guo
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, Shandong, China.
| | - Gui-Yun Chen
- State Key Laboratory of Food Nutrition and Safety, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China
| | - Nan Jin
- State Key Laboratory of Food Nutrition and Safety, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China
| | - Ye Chen
- State Key Laboratory of Food Nutrition and Safety, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.
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14
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Chaplot S, Yadav B, Jeon B, Roopesh MS. Atmospheric Cold Plasma and Peracetic Acid-Based Hurdle Intervention To Reduce Salmonella on Raw Poultry Meat. J Food Prot 2019; 82:878-888. [PMID: 31017813 DOI: 10.4315/0362-028x.jfp-18-377] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
HIGHLIGHTS Atmospheric cold plasma and peracetic acid-based hurdle approach for safety of poultry products was evaluated. Study demonstrates a significant synergetic approach to reducing Salmonella on raw poultry. Hurdle approach shows promising bacterial reduction but requires further optimization.
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Affiliation(s)
- Shreyak Chaplot
- 1 Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5; and
| | - Barun Yadav
- 1 Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5; and
| | - Byeonghwa Jeon
- 2 School of Public Health, University of Alberta, Edmonton, Alberta, Canada T6G 1C9
| | - M S Roopesh
- 1 Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5; and
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15
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Patange A, Boehm D, Ziuzina D, Cullen PJ, Gilmore B, Bourke P. High voltage atmospheric cold air plasma control of bacterial biofilms on fresh produce. Int J Food Microbiol 2019; 293:137-145. [PMID: 30711711 DOI: 10.1016/j.ijfoodmicro.2019.01.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [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: 07/20/2018] [Revised: 01/02/2019] [Accepted: 01/09/2019] [Indexed: 12/24/2022]
Abstract
Atmospheric cold plasma (ACP) offers great potential for decontamination of food borne pathogens. This study examined the antimicrobial efficacy of ACP against a range of pathogens of concern to fresh produce comparing planktonic cultures, monoculture biofilms (Escherichia coli, Salmonella enterica, Listeria monocytogenes, Pseudomonas fluorescens) and mixed culture biofilms (Listeria monocytogenes and Pseudomonas fluorescens). Biotic and abiotic surfaces commonly occurring in the fresh food industry were investigated. Microorganisms showed varying susceptibility to ACP treatment depending on target and process factors. Bacterial biofilm populations treated with high voltage (80 kV) ACP were reduced significantly (p < 0.05) in both mono- and mixed species biofilms after 60 s of treatment and yielded non-detectable levels after extending treatment time to 120 s. However, an extended time was required to reduce the challenge mixed culture biofilm of L. monocytogenes and P. fluorescens inoculated on lettuce, which was dependent on biofilm formation conditions and substrate. Contained treatment for 120 s reduced L. monocytogenes and P. fluorescens inoculated as mixed cultures on lettuce (p < 0.05) by 2.2 and 4.2 Log10 CFU/ml respectively. When biofilms were grown at 4 °C on lettuce, there was an increased resistance to ACP treatment by comparison with biofilm grown at temperature abuse conditions of 15 °C. Similarly, L. monocytogenes and P. fluorescens exposed to cold stress (4 °C) for 1 h demonstrated increased tolerance to ACP treatment compared to non-stressed cells. These finding demonstrates that bacterial form, mono versus mixed challenges as well as environmental stress conditions play an important role in ACP inactivation efficacy.
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Affiliation(s)
- Apurva Patange
- Plasma Research Group, School of Food Science and Environmental Health, Technological University Dublin, Dublin 1, Ireland
| | - D Boehm
- Plasma Research Group, School of Food Science and Environmental Health, Technological University Dublin, Dublin 1, Ireland
| | - Dana Ziuzina
- Plasma Research Group, School of Food Science and Environmental Health, Technological University Dublin, Dublin 1, Ireland
| | - P J Cullen
- Plasma Research Group, School of Food Science and Environmental Health, Technological University Dublin, Dublin 1, Ireland
| | - Brendan Gilmore
- Biofilm Research Group, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast BT97BL, UK
| | - Paula Bourke
- Plasma Research Group, School of Food Science and Environmental Health, Technological University Dublin, Dublin 1, Ireland.
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16
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Liao X, Cullen PJ, Liu D, Muhammad AI, Chen S, Ye X, Wang J, Ding T. Combating Staphylococcus aureus and its methicillin resistance gene (mecA) with cold plasma. Sci Total Environ 2018; 645:1287-1295. [PMID: 30248853 DOI: 10.1016/j.scitotenv.2018.07.190] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [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: 04/25/2018] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 06/08/2023]
Abstract
The increase in antibiotic resistance has become a global challenge to public health. In this study, an atmospheric cold plasma (ACP) system was applied for combating methicillin-resistant Staphylococcus aureus (MRSA) and its methicillin resistance gene (mecA) during food wastewater treatment. The plate count and flow cytometry methods were employed to estimate the damage in MRSA induced by plasma treatment. A quantitative real-time PCR (qPCR) method was used to assess the plasma-induced degradation of the mecA genes. The inactivation of MRSA and degradation of extracellular (e-) and intracellular (i-)mecA genes were investigated in phosphate buffered solution as a function of plasma exposure. A relatively low plasma influence of 0.12 kJ/cm2 accounted for 5-log MRSA and 1.4-log e-mecA genes reduction, while only around 0.19-log degradation for i-mecA genes. As the plasma intensity was accumulated to 0.35 kJ/cm2, the reduction of e- and i-mecA genes was increased to 2.6 and 0.8 logs, respectively. The degradation of i-mecA genes was much slower than that of e-mecA genes due to the protective effects of the outer envelopes or intracellular components against plasma. The matrix effect of wastewater effluents shielded both antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) from plasma disinfection, which led to a lower degradation efficacy. Our results could support the development and optimization of plasma-based wastewater treatment.
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Affiliation(s)
- Xinyu Liao
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - P J Cullen
- BioPlasma Research Group, Dublin Institute of Technology, Dublin, Ireland; Department of Chemical and Environmental Engineering, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Donghong Liu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Aliyu Idris Muhammad
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China; Department of Agricultural and Environmental Engineering, Faculty of Engineering, Bayero University Kano, Nigeria
| | - Shiguo Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China
| | - Xingqian Ye
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China
| | - Jun Wang
- College of Food Science and Engineering, Qingdao Agricultural University, Chengyang, Qingdao, China
| | - Tian Ding
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang 310058, China; Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Hangzhou, Zhejiang 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou, Zhejiang 310058, China.
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17
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Ziuzina D, Han L, Cullen PJ, Bourke P. Cold plasma inactivation of internalised bacteria and biofilms for Salmonella enterica serovar Typhimurium, Listeria monocytogenes and Escherichia coli. Int J Food Microbiol 2015; 210:53-61. [PMID: 26093991 DOI: 10.1016/j.ijfoodmicro.2015.05.019] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [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: 01/20/2015] [Revised: 05/12/2015] [Accepted: 05/27/2015] [Indexed: 10/23/2022]
Abstract
Microbial biofilms and bacteria internalised in produce tissue may reduce the effectiveness of decontamination methods. In this study, the inactivation efficacy of in-package atmospheric cold plasma (ACP) afterglow was investigated against Salmonella Typhimurium, Listeria monocytogenes and Escherichia coli in the forms of planktonic cultures, biofilms formed on lettuce and associated bacteria internalised in lettuce tissue. Prepared lettuce broth (3%) was inoculated with bacteria resulting in a final concentration of ~7.0 log10 CFU/ml. For biofilm formation and internalisation, lettuce pieces (5 × 5 cm) were dip-inoculated in bacterial suspension of ~7.0 log10 CFU/ml for 2 h and further incubated for 0, 24 and 48 h at either 4 °C or room temperature (~22 °C) in combination with light/dark photoperiod or at 4 °C under dark conditions. Inoculated samples were sealed inside a rigid polypropylene container and indirectly exposed (i.e. placed outside plasma discharge) to a high voltage (80 kVRMS) air ACP with subsequent storage for 24 h at 4 °C. ACP treatment for 30s reduced planktonic populations of Salmonella, L. monocytogenes and E. coli suspended in lettuce broth to undetectable levels. Depending on storage conditions, bacterial type and age of biofilm, 300 s of treatment resulted in reduction of biofilm populations on lettuce by a maximum of 5 log10 CFU/sample. Scanning electron and confocal laser microscopy pointed to the incidence of bacterial internalisation and biofilm formation, which influenced the inactivation efficacy of ACP. Measured intracellular reactive oxygen species (ROS) revealed that the presence of organic matter in the bacterial suspension might present a protective effect against the action of ROS on bacterial cells. This study demonstrated that high voltage in-package ACP could be a potential technology to overcome bacterial challenges associated with food produce. However, the existence of biofilms and internalised bacteria should be considered for further optimisation of ACP treatment parameters in order to achieve an effective control of the realistic challenges posed by foodborne pathogens.
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Affiliation(s)
- Dana Ziuzina
- Plasma Research Group, School of Food Science and Environmental Health, Dublin Institute of Technology, Dublin 1, Ireland
| | - Lu Han
- Plasma Research Group, School of Food Science and Environmental Health, Dublin Institute of Technology, Dublin 1, Ireland
| | - Patrick J Cullen
- School of Chemical Engineering, University of New South Wales, Sydney, Australia
| | - Paula Bourke
- Plasma Research Group, School of Food Science and Environmental Health, Dublin Institute of Technology, Dublin 1, Ireland.
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