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Yang S, Meng X, Zhen Y, Baima Q, Wang Y, Jiang X, Xu Z. Strategies and mechanisms targeting Enterococcus faecalis biofilms associated with endodontic infections: a comprehensive review. Front Cell Infect Microbiol 2024; 14:1433313. [PMID: 39091674 PMCID: PMC11291369 DOI: 10.3389/fcimb.2024.1433313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Accepted: 07/05/2024] [Indexed: 08/04/2024] Open
Abstract
Enterococcus faecalis is one of the main microorganisms that infects root canals, ranking among the most prevalent microorganisms associated with endodontic treatment failure. Given its pervasive presence in persistent endodontic infections, the successful elimination of Enterococcus faecalis is crucial for effective endodontic treatment and retreatment. Furthermore, Enterococcus faecalis can form biofilms - defense structures that microbes use to fight environmental threats. These biofilms confer resistance against host immune system attacks and antibiotic interventions. Consequently, the presence of biofilms poses a significant challenge in the complete eradication of Enterococcus faecalis and its associated disease. In response, numerous scholars have discovered promising outcomes in addressing Enterococcus faecalis biofilms within root canals and undertaken endeavors to explore more efficacious approaches in combating these biofilms. This study provides a comprehensive review of strategies and mechanisms for the removal of Enterococcus faecalis biofilms.
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Affiliation(s)
- Shipeng Yang
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Xiuping Meng
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Yuqi Zhen
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Quzhen Baima
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Yu Wang
- Department of Dental Implantology, Hospital of Stomatology, Jilin University, Changchun, China
| | - Xinmiao Jiang
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
| | - Zhibo Xu
- Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun, China
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Lee MJ, Kim MA, Min KS. Combined effect of electrical energy and graphene oxide on Enterococcus faecalis biofilms. Dent Mater J 2023; 42:844-850. [PMID: 37914231 DOI: 10.4012/dmj.2023-087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
This study aimed to investigate the effects of electrical energy and its synergistic activity with graphene oxide (GO) in Enterococcus faecalis (E. faecalis) biofilms. The viability of E. faecalis biofilms was analyzed by colony-forming units, crystal violet staining, and confocal laser scanning microscopy. The morphologies of the biofilms and the bacterial organelles were observed by scanning electron microscopy and transmission emission microscopy (TEM), respectively. Application of electrical energy combined with 0.2% sodium hypochlorite (NaOCl) on E. faecalis in biofilms significantly decreased the bacterial viability and biofilm biomass compared to the 0.2% NaOCl-only-treated group. Furthermore, additional application of GO showed similar antibacterial effects to 0.5% NaOCl. Notably, TEM observation revealed that the bacteria treated with electric energy and GO showed damaged cell membranes. The results suggest that combination of electrical energy and GO enhances antibacterial activity of NaOCl and has the potential to be applied to root canal irrigation protocols.
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Affiliation(s)
- Myung-Jin Lee
- Department of Conservative Dentistry, School of Dentistry, Seoul National University
| | - Mi-Ah Kim
- Department of Conservative Dentistry, School of Dentistry and Institute of Oral Bioscience, Jeonbuk National University
| | - Kyung-San Min
- Department of Conservative Dentistry, School of Dentistry and Institute of Oral Bioscience, Jeonbuk National University
- Research Institute of Clinical Medicine of Jeonbuk National University
- Biomedical Research Institute of Jeonbuk National University Hospital
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Mendoza-Tinoco TP, Sánchez-Vázquez V, Del Carmen Fajardo-Ortiz M, González I, Beristain-Cardoso R. How does a low-magnitude electric field influence anaerobic digestion in wastewater treatment? A review. CHEMOSPHERE 2023; 325:138402. [PMID: 36921776 DOI: 10.1016/j.chemosphere.2023.138402] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 03/06/2023] [Accepted: 03/12/2023] [Indexed: 06/18/2023]
Abstract
Anaerobic digestion (AD) is a physio-biochemical process widely used for treating industrial or municipal wastewater with concomitant methane production. Several technologies have been tested to improve AD's efficiency, like pretreatments and co-digestion, among others. Recently the imposition of a low-magnitude electric field (LMEF) has been applied at the AD to improve methane yield. Despite the positive results of imputing an electric field, many gaps are not understood yet. Therefore, this review focuses on the biochemical aspects of AD and electric field for a better understanding of the effect of the LMEF on the metabolisms of the AD during wastewater treatment and its application in methane production enhancement.
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Affiliation(s)
- Tania Paola Mendoza-Tinoco
- Departamento de Biotecnología, Av. San Rafael Atlixco, No. 186, Col. Leyes de Reforma, C.P. 09310, Ciudad de México, Mexico
| | - Víctor Sánchez-Vázquez
- Departamento de Ingeniería de Procesos e Hidráulica, Av. San Rafael Atlixco, No. 186, Col. Leyes de Reforma, C.P. 09310, Ciudad de México, Mexico
| | - María Del Carmen Fajardo-Ortiz
- Departamento de Biotecnología, Av. San Rafael Atlixco, No. 186, Col. Leyes de Reforma, C.P. 09310, Ciudad de México, Mexico
| | - Ignacio González
- Departamento de Química, Universidad Autónoma Metropolitana Unidad Iztapalapa, Av. San Rafael Atlixco, No. 186, Col. Leyes de Reforma, C.P. 09310, Ciudad de México, Mexico
| | - Ricardo Beristain-Cardoso
- Departamento de Recursos de La Tierra, Universidad Autónoma Metropolitana Unidad Lerma, Av. De Las Garzas, No, 10, Col. El Panteón, C.P.52005, Municipio Lerma de Villada, Estado de México, Mexico.
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Calcareous deposit formation under cathodic polarization and marine biocalcifying bacterial activity. Bioelectrochemistry 2022; 148:108271. [DOI: 10.1016/j.bioelechem.2022.108271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/22/2022]
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Woroszyło M, Ciecholewska-Juśko D, Junka A, Pruss A, Kwiatkowski P, Wardach M, Fijałkowski K. The Impact of Intraspecies Variability on Growth Rate and Cellular Metabolic Activity of Bacteria Exposed to Rotating Magnetic Field. Pathogens 2021; 10:1427. [PMID: 34832583 PMCID: PMC8624435 DOI: 10.3390/pathogens10111427] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 12/02/2022] Open
Abstract
Majority of research on the influence of magnetic fields on microorganisms has been carried out with the use of different species or different groups of microorganisms, but not with the use of different strains belonging to one species. The purpose of the present study was to assess the effect of rotating magnetic fields (RMF) of 5 and 50 Hz on the growth and cellular metabolic activity of eight species of bacteria: Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Enterococcus faecalis, Enterobacter cloacae, Moraxella catarrhalis, and Bacillus cereus. However, contrary to the research conducted so far, each species was represented by at least four different strains. Moreover, an additional group of S. aureus belonging to a single clonal type but representing different biotypes was also included in the experiment. The results showed a varied influence of RMF on growth dynamics and cellular metabolic activity, diversified to the greatest extent in dependence on the bacterial strain exposed to the RMF and to a lesser extent in dependence on the frequency of the generated magnetic field. It was found that, with regard to the exposed strain of the same species, the effect exerted by the RMF may be positive (i.e., manifests as the increase in the growth rate or/and cellular metabolic activity) or negative (i.e., manifests as a reduction of both aforementioned features) or none. Even when one clonal type of S. aureus was used, the results of RMF exposure also varied (although the degree of differentiation was lower than for strains representing different clones). Therefore, the research has proven that, apart from the previously described factors related primarily to the physical parameters of the magnetic field, one of the key parameters affecting the final result of its influence is the bacterial intraspecies variability.
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Affiliation(s)
- Marta Woroszyło
- Department of Microbiology and Biotechnology, Faculty of Biotechnology and Animal Husbandry, West Pomeranian University of Technology in Szczecin, Piastów 45, 70-311 Szczecin, Poland; (M.W.); (D.C.-J.)
| | - Daria Ciecholewska-Juśko
- Department of Microbiology and Biotechnology, Faculty of Biotechnology and Animal Husbandry, West Pomeranian University of Technology in Szczecin, Piastów 45, 70-311 Szczecin, Poland; (M.W.); (D.C.-J.)
| | - Adam Junka
- Department of Pharmaceutical Microbiology and Parasitology, Faculty of Pharmacy, Medical University of Wroclaw, Borowska 211a, 50-534 Wrocław, Poland
- Laboratory of Microbiology, Łukasiewicz Research Network-PORT Polish Center for Technology Development, 54-066 Wrocław, Poland
| | - Agata Pruss
- Department of Laboratory Medicine, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland;
| | - Paweł Kwiatkowski
- Department of Diagnostic Immunology, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland;
| | - Marcin Wardach
- Faculty of Electrical Engineering, West Pomeranian University of Technology in Szczecin, Sikorskiego 37, 70-313 Szczecin, Poland;
| | - Karol Fijałkowski
- Department of Microbiology and Biotechnology, Faculty of Biotechnology and Animal Husbandry, West Pomeranian University of Technology in Szczecin, Piastów 45, 70-311 Szczecin, Poland; (M.W.); (D.C.-J.)
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Minkiewicz-Zochniak A, Strom K, Jarzynka S, Iwańczyk B, Koryszewska-Bagińska A, Olędzka G. Effect of Low Amperage Electric Current on Staphylococcus Aureus-Strategy for Combating Bacterial Biofilms Formation on Dental Implants in Cystic Fibrosis Patients, In Vitro Study. MATERIALS 2021; 14:ma14206117. [PMID: 34683710 PMCID: PMC8537792 DOI: 10.3390/ma14206117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/09/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022]
Abstract
Cystic fibrosis is an inherited disease that affects multiple organs and systems. The oral cavity can serve as a substantial source of bacteria, causing respiratory infections and diseases which continue to dictate the clinical course of the disease and prognosis in patients with CF. Low voltage and electric current could effectively kill bacteria and biofilms, and the activity of milliampere currents could be used as an effective method of fighting bacteria. This study evaluated the effect of low amperage electric current on the formation of Staphylococcus aureus biofilms on dental implants such as titanium and zirconium in patients with cystic fibrosis. Our studies suggest that a constant electric current at a low intensity of 1 mA and 10 mA is inhibiting bacterial adhesion, detaching biofilm-forming bacteria on biomaterials used in dental implants such as titanium and zirconium, and destroying bacterial cells of Staphylococcus aureus strains. In addition, we observed the selection of an appropriate biomaterial for implants in people affected by chronic diseases, such as CF, should be carefully planned.
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Affiliation(s)
- Anna Minkiewicz-Zochniak
- Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland; (A.M.-Z.); (K.S.); (S.J.); (A.K.-B.)
| | - Kamila Strom
- Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland; (A.M.-Z.); (K.S.); (S.J.); (A.K.-B.)
| | - Sylwia Jarzynka
- Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland; (A.M.-Z.); (K.S.); (S.J.); (A.K.-B.)
| | - Bartłomiej Iwańczyk
- Department of Oral Surgery, Medical University of Lublin, Karmelicka 7, 20-081 Lublin, Poland;
| | - Anna Koryszewska-Bagińska
- Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland; (A.M.-Z.); (K.S.); (S.J.); (A.K.-B.)
| | - Gabriela Olędzka
- Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland; (A.M.-Z.); (K.S.); (S.J.); (A.K.-B.)
- Correspondence:
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M. Shawki M, M. Eltarahony M, E. Moustafa M. The impact of titanium oxide nanoparticles and low direct electric current on biofilm dispersal of $Bacillus~cereus$ and $Pseudomonas~aeruginosa$: A comparative study. PAPERS IN PHYSICS 2021. [DOI: 10.4279/pip.130005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Bacteria growing in biofilms cause a wide range of environmental, industrial and public health risks. Because biofilm bacteria are very resistant to antibiotics, there is an urgent need in medicine and industry to develop new approaches to eliminating bacterial biofilms. One strategy for controlling these biofilms is to generate an antibiofilm substance locally at the attachment surface. Direct electric current (DC) and nanoparticles (NPs) of metal oxides have outstanding antimicrobial properties. In this study we evaluated the effect of titanium oxide nanoparticle (TiO$_2$-NP) concentrations from 5 to 160 $\mu$g/mL on Bacillus cereus and Pseudomonas aeruginosa biofilms, and compared this with the effect of a 9 V, 6 mA DC electric field for 5, 10 and 15 min. TiO$_2$-NPs were characterized using transmission and scanning electron microscopes, X-ray diffraction and FTIR. They exhibited an average size of 22-34 nm. The TiO$_2$-NP concentrations that attained LD50 were $104 \pm 4$ $\mu$g/mL and $63 \pm 3$ $\mu$g/mL for B. cereus and P. aeruginosa, respectively. The eradication percentages obtained by DC at 5, 10, and 15 min exposure were 21%, 29%, and 33% respectively for B. cereus and 30%, 39%, and 44% respectively for P. aeruginosa. Biofilm disintegration was verified by exopolysaccharide, protein content and cell surface hydrophobicity assessment, as well as scanning electron microscopy. These data were correlated with the reactive oxygen species produced. The results indicated that both DC and TiO$_2$-NPs have a lethal effect on these bacterial biofilms, and that the DC conditions used affect the biofilms in a similar way to TiO$_2$-NPs at concentrations of 20-40 $\mu$g/mL.
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Marito S, Keshari S, Traisaeng S, My DTT, Balasubramaniam A, Adi P, Hsieh MF, Herr DR, Huang CM. Electricity-producing Staphylococcus epidermidis counteracts Cutibacterium acnes. Sci Rep 2021; 11:12001. [PMID: 34099817 PMCID: PMC8184966 DOI: 10.1038/s41598-021-91398-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 05/10/2021] [Indexed: 12/19/2022] Open
Abstract
Staphylococcus epidermidis (S. epidermidis) ATCC 12228 was incubated with 2% polyethylene glycol (PEG)-8 Laurate to yield electricity which was measured by a voltage difference between electrodes. Production of electron was validated by a Ferrozine assay. The anti-Cutibacterium acnes (C. acnes) activity of electrogenic S. epidermidis was assessed in vitro and in vivo. The voltage change (~ 4.4 mV) reached a peak 60 min after pipetting S. epidermidis plus 2% PEG-8 Laurate onto anodes. The electricity produced by S. epidermidis caused significant growth attenuation and cell lysis of C. acnes. Intradermal injection of C. acnes and S. epidermidis plus PEG-8 Laurate into the mouse ear considerably suppressed the growth of C. acnes. This suppressive effect was noticeably reversed when cyclophilin A of S. epidermidis was inhibited, indicating the essential role of cyclophilin A in electricity production of S. epidermidis against C. acnes. In summary, we demonstrate for the first time that skin S. epidermidis, in the presence of PEG-8 Laurate, can mediate cyclophilin A to elicit an electrical current that has anti-C. acnes effects. Electricity generated by S. epidermidis may confer immediate innate immunity in acne lesions to rein in the overgrowth of C. acnes at the onset of acne vulgaris.
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Affiliation(s)
- Shinta Marito
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Sunita Keshari
- Department of Life Sciences, National Central University, Taoyuan, Taiwan
| | | | - Do Thi Tra My
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Arun Balasubramaniam
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Prakoso Adi
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Ming-Fa Hsieh
- Department of Biomedical Engineering, Chung Yuan Christian University, Taoyuan, Taiwan
| | | | - Chun-Ming Huang
- Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan.
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Microampere Electric Current Causes Bacterial Membrane Damage and Two-Way Leakage in a Short Period of Time. Appl Environ Microbiol 2020; 86:AEM.01015-20. [PMID: 32561580 DOI: 10.1128/aem.01015-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/12/2020] [Indexed: 01/26/2023] Open
Abstract
Physical agents, such as low electric voltage and current, have recently gained attention for antimicrobial treatment due to their bactericidal capability. Although microampere electric current was shown to suppress the growth of bacteria, it remains unclear to what extent the microampere current damaged the bacterial membrane. Here, we investigated the membrane damage and two-way leakage caused by microampere electric current (≤100 μA) with a short exposure time (30 min). Based on MitoTracker staining, propidium iodide staining, filtration assays, and quantitative single-molecule localization microscopy, we observed significant membrane damage, which allowed two-way leakage of ions, small molecules, and proteins. This study paves the way to new development of antimicrobial applications for ultralow electric voltage and current.IMPORTANCE Although electric voltage and current have been studied for a long time in terms of their ability to suppress the growth of bacteria and to kill bacteria, increasing interest has been aroused more recently due to the prevalence of antibiotic resistance of microbes in past decades. Toward understanding the antimicrobial mechanism of low electric voltage and current, previous studies showed that treating bacteria with milliampere electric currents (≥5 mA) for ≥72 h led to significant damage of the bacterial membrane, which likely resulted in leakage of cellular contents and influx of toxic substances through the damaged membrane. However, it remains unclear to what extent membrane damage and two-way (i.e., inward and outward) leakage are caused by lower (i.e., microampere) electric current in a shorter time frame. In this work, we set out to answer this question. We observed that the membrane damage was caused by microampere electric current in half an hour, which allowed two-way leakage of ions, small molecules, and proteins.
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Cházaro-Ruiz LF, López-Cázares MI, González I, Toriz Y, Alatriste-Mondragon F, Santana M, Celis LB. Improving Substrate Consumption and Decrease of Growth Yield in Aerobic Cultures of Pseudomonas denitrificans By Applying Low Voltages in Bioelectric Systems. Appl Biochem Biotechnol 2019; 190:1333-1348. [PMID: 31758363 DOI: 10.1007/s12010-019-03168-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 10/23/2019] [Indexed: 12/22/2022]
Abstract
It is well known that activated sludge treatment systems generate a lot of surplus sludge having environmental and economic impacts. Although several approaches have been proposed for the treatment/reuse of the excess of sludge, there are few studies focused on decreasing the biomass yield without affecting the metabolic activity. This work reports the effect of low magnitude electrical fields (0.07 to 0.2 V/cm) on the growth yield of a pure strain of Pseudomonas denitrificans (used as model microorganism). Cell potentials between 0.2 and 0.57 V were measured during 24 h to the aerobic culture; biomass production and substrate consumption were evaluated at regular intervals. Results indicated that the substrate (lactate) consumption efficiency increased with the applied potential, up to 100%, while the yield diminished 31% (0.34 g biomass/g lactate consumed) at 0.7 V vs. NHE. Bioenergetics showed that the fraction of electron equivalents toward biomass synthesis decreased from 0.68 (when no potential was applied) to 0.47 at 0.57 V, pointing out the redirection of the energy flow toward maintenance to cope with the stress caused by the imposed voltage. Therefore, the electrical stimulus could be used as control of biomass growth in aerobic wastewater treatment lines.
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Affiliation(s)
- Luis F Cházaro-Ruiz
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico.
| | - María Irene López-Cázares
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico
| | - Ignacio González
- Departamento de Química, Universidad Autónoma Metropolitana - Iztapalapa, Apdo. Postal 55-534, 09340, México City, 09340, Mexico
| | - Yanet Toriz
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico
| | - Felipe Alatriste-Mondragon
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico
| | - Marcela Santana
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico
| | - Lourdes B Celis
- División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a. Sección, San Luis Potosí, S.L.P, C.P.78216, México, Mexico.
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11
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da Silva FAG, Alcaraz-Espinoza JJ, da Costa MM, de Oliveira HP. Low intensity electric field inactivation of Gram-positive and Gram-negative bacteria via metal-free polymeric composite. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 99:827-837. [PMID: 30889757 DOI: 10.1016/j.msec.2019.02.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 02/01/2019] [Accepted: 02/10/2019] [Indexed: 12/30/2022]
Abstract
The adhesion of pathogenic bacteria in medical implants and surfaces is a health-related problem that requires strong inhibition against bacterial growth and attachment. In this work, we have explored the enhancement in the antibacterial activity of metal free-based composites under external electric field. It affects the oxidation degree of polypyrrole-based electrodes and consequently the antibacterial activity of the material. A conductive layer of carbon nanotubes (graphite) was deposited on porous substrate of polyurethane (sandpaper) and covered by polypyrrole, providing highly conductive electrodes characterized by intrinsic antibacterial activity and reinforced by electro-enhanced effect due to the external electric field. The bacterial inhibition of composites was monitored from counting of viable cells at different voltage/time of treatment and determination of biofilm inhibition on electrodes and reactors. The external voltage on electrodes reduces the threshold time for complete bacterial inactivation of PPy-based composites to values in order of 30 min for Staphylococcus aureus and 60 min for Escherichia coli.
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Affiliation(s)
- Fernando A G da Silva
- Institute of Materials Science, Federal University of Sao Francisco Valley, 48920-310 Juazeiro, BA, Brazil
| | | | - Mateus M da Costa
- Institute of Materials Science, Federal University of Sao Francisco Valley, 48920-310 Juazeiro, BA, Brazil
| | - Helinando P de Oliveira
- Institute of Materials Science, Federal University of Sao Francisco Valley, 48920-310 Juazeiro, BA, Brazil.
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12
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Li H, Yang XL, Song HL, Zhang S, Long XZ. Effects ofdirect current on Klebsiella spp. viability and corresponding resistance gene expression in simulative bio-electrochemical reactors. CHEMOSPHERE 2018; 196:251-259. [PMID: 29306197 DOI: 10.1016/j.chemosphere.2017.12.176] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 12/02/2017] [Accepted: 12/27/2017] [Indexed: 06/07/2023]
Abstract
The fate of antibiotic-resistant bacteria (ARB) and associated antibiotic-resistant gene (ARG) expression under electrolytic stimulation in bio-electrochemical reactors (BERs) was unknown. In this study, sulfadiazine resistant bacteria (Klebsiella spp.), which were isolated from a BER, were subjected to constant direct current (DC) stimulation in a simulated BER. With an increase of the current from 7 to 28 mA, it was found that lactic dehydrogenase (LDH) showed a 1.03-, 1.21-, 1.34-, and 1.46-fold value compared with the control at 48 h, indicating that the cell membrane permeability had increased. Since the adenosine triphosphate (ATP) concentration increased with the current, the specific growth rate of Klebsiella spp. increased (R = 0.98). The viable count of Klebsiella spp. reached a maximum at 19 mA and then decreased. The percentage of ARB lethality, which was reflected by flow cytometry analysis, increased from 18% (7 mA) to 37.8% (28 mA) at 48 h. Reactive oxygen species (ROS) produced from the electrolysis of water were greater with the increasing current (R = 0.94), which may be responsible for the high lethality rate of Klebsiella spp.. Scanning electronic microscope results showed that electrolytic stimulation changed the cell surface morphology with some cell disruption. An upregulation of sulII and int1 expression was observed. A significant correlation between int1 and the current (R = 0.97) were observed. Taken together, BERs possess potential risks in accelerating ARB multiplication and promoting ARG expression.
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Affiliation(s)
- Hua Li
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Xiao-Li Yang
- School of Civil Engineering, Southeast University, Nanjing 210096, China.
| | - Hai-Liang Song
- School of Environment, Nanjing Normal University, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Wenyuan Road 1, Nanjing 210023, China.
| | - Shuai Zhang
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Xi-Zi Long
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
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Maden M, Ertuğrul İF, Orhan EO, Erik CE, Yetiş CÇ, Tuncer Y, Kahriman M. Enhancing antibacterial effect of sodium hypochlorite by low electric current-assisted sonic agitation. PLoS One 2017; 12:e0183895. [PMID: 28854274 PMCID: PMC5576683 DOI: 10.1371/journal.pone.0183895] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 08/13/2017] [Indexed: 11/18/2022] Open
Abstract
Background This research focused on the effects of low electric current (μE)-assisted sonic agitation of sodium hypochlorite on Enterococcus faecalis infected human root dentin. Methods Extracted human canine roots were instrumented, sterilized, and experimentally contaminated with E. faecalis. After incubation for 21 days, the presence of the biofilm was confirmed by scanning electron microscopy (n = 3). Roots were randomly divided into seven groups according to decontamination procedures: G1: no treatment; G2: sterile saline; G3: 5.25% sodium hypochlorite; G4: passive ultrasonic irrigation; G5: EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) agitation (EA); G6: μE agitation; and G7: μE-assisted sonic agitation. Fixed μE amperage and intensities were applied in G6 and G7. Following microbial sampling, bacterial colonies were counted using the direct plating method. Results Biofilm was not eradicated in any sample. The μE-assisted sonic agitation of sodium hypochlorite revealed the lowest cfu values (p<0.05), whereas there were no significant differences among the passive ultrasonic irrigation, EndoActivator and μE agitation alone (p>0.05). Conclusions Based on available evidence, the following conclusions were drawn: The μE-assisted sonic agitation increased the antibiofilm efficiency of sodium hypochlorite than passive ultrasonic irrigation and EndoActivator. The μE-assisted sonic agitation on 5.25% sodium hypochlorite is not capable to eradicate biofilms at 10mA energy level in 60s.
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Affiliation(s)
- Murat Maden
- Department of Endodontics, Faculty of Dentistry, Süleyman Demirel University, Isparta, Turkey
| | - İhsan Furkan Ertuğrul
- Department of Endodontics Dentistry, Faculty of Dentistry, Pamukkale University, Denizli, Turkey
| | - Ekim Onur Orhan
- Department of Endodontics, Faculty of Dentistry, Eskişehir Osmangazi University, Eskişehir, Turkey
- * E-mail:
| | - Cevat Emre Erik
- Department of Endodontics, Faculty of Dentistry, Süleyman Demirel University, Isparta, Turkey
| | - Ceylan Çağıl Yetiş
- Department of Pediatric Dentistry, Faculty of Dentistry, Süleyman Demirel University, Isparta, Turkey
| | - Yasin Tuncer
- Department of Food Engineering, Faculty of Engineering and Architect, Süleyman Demirel University, Isparta, Turkey
| | - Mesud Kahriman
- Department of Electronics and Communication, Faculty of Engineering & Architect, Süleyman Demirel University, Isparta, Turkey
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Chen W, Hu H, Zhang C, Huang F, Zhang D, Zhang H. Adaptation response of Pseudomonas fragi on refrigerated solid matrix to a moderate electric field. BMC Microbiol 2017; 17:32. [PMID: 28187702 PMCID: PMC5303209 DOI: 10.1186/s12866-017-0945-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 02/03/2017] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Moderate electric field (MEF) technology is a promising food preservation strategy since it relies on physical properties-rather than chemical additives-to preserve solid cellular foods during storage. However, the effectiveness of long-term MEF exposure on the psychrotrophic microorganisms responsible for the food spoilage at cool temperatures remains unclear. RESULTS The spoilage-associated psychrotroph Pseudomonas fragi MC16 was obtained from pork samples stored at 7 °C. Continuous MEF treatment attenuated growth and resulted in subsequent adaptation of M16 cultured on nutrient agar plates at 7 °C, compared to the control cultures, as determined by biomass analysis and plating procedures. Moreover, intracellular dehydrogenase activity and ATP levels also indicated an initial effect of MEF treatment followed by cellular recovery, and extracellular β-galactosidase activity assays indicated no obvious changes in cell membrane permeability. Furthermore, microscopic observations using scanning and transmission electron microscopy revealed that MEF induced sublethal cellular injury during early treatment stages, but no notable changes in morphology or cytology on subsequent days. CONCLUSION Our study provides direct evidence that psychrotrophic P. fragi MC16 cultured on nutrient agar plates at 7 °C are capable of adapting to MEF treatment.
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Affiliation(s)
- Wenbo Chen
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
- College of Staple Food Technology, Chinese Academy of Agricultural Sciences, Institute of Food Science and Technology, Harbin, 151900 People’s Republic of China
| | - Honghai Hu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
- College of Staple Food Technology, Chinese Academy of Agricultural Sciences, Institute of Food Science and Technology, Harbin, 151900 People’s Republic of China
| | - Chunjiang Zhang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
- College of Staple Food Technology, Chinese Academy of Agricultural Sciences, Institute of Food Science and Technology, Harbin, 151900 People’s Republic of China
| | - Feng Huang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
- College of Staple Food Technology, Chinese Academy of Agricultural Sciences, Institute of Food Science and Technology, Harbin, 151900 People’s Republic of China
| | - Dequan Zhang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
| | - Hong Zhang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, 100193 People’s Republic of China
- College of Staple Food Technology, Chinese Academy of Agricultural Sciences, Institute of Food Science and Technology, Harbin, 151900 People’s Republic of China
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15
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Enhancement of production and activity of alkaline zinc metalloprotease from Salinivibrio proteolyticus using low intensity direct electric current and zinc nanoparticles. Biotechnol Lett 2016; 38:1565-70. [PMID: 27259725 DOI: 10.1007/s10529-016-2132-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 05/25/2016] [Indexed: 10/21/2022]
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Bundhoo MAZ, Mohee R, Hassan MA. Effects of pre-treatment technologies on dark fermentative biohydrogen production: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 157:20-48. [PMID: 25881150 DOI: 10.1016/j.jenvman.2015.04.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 04/05/2015] [Accepted: 04/07/2015] [Indexed: 05/24/2023]
Abstract
Biohydrogen production from dark fermentation of lignocellulosic materials represents a huge potential in terms of renewable energy exploitation. However, the low hydrogen yield is currently hindering its development on industrial scale. This study reviewed various technologies that have been investigated for enhancing dark fermentative biohydrogen production. The pre-treatment technologies can be classified based on their applications as inoculum or substrates pre-treatment or they can be categorised into physical, chemical, physicochemical and biological based on the techniques used. From the different technologies reviewed, heat and acid pre-treatments are the most commonly studied technologies for both substrates and inoculum pre-treatment. Nevertheless, these two technologies need not necessarily be the most suitable since across different studies, a wide array of other emerging techniques as well as combined technologies have yielded positive findings. To date, there exists no perfect technology for either inoculum or substrate pre-treatment. Although the aim of inoculum pre-treatment is to suppress H2-consumers and enrich H2-producers, many sporulating H2-consumers survive the pre-treatment while some non-spore H2-producers are inhibited. Besides, several inoculum pre-treatment techniques are not effective in the long run and repeated pre-treatment may be required for continuous suppression of H2-consumers and sustained biohydrogen production. Furthermore, many technologies employed for substrates pre-treatment may yield inhibitory compounds that can eventually decrease biohydrogen production. Consequently, much research needs to be done to find out the best technology for both substrates and inoculum pre-treatment while also taking into consideration the energetic, economic and technical feasibility of implementing such a process on an industrial scale.
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Affiliation(s)
- M A Zumar Bundhoo
- Department of Chemical & Environmental Engineering, Faculty of Engineering, University of Mauritius, Réduit, Mauritius.
| | | | - M Ali Hassan
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor Darul Ehsan, Malaysia.
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Silver-zinc redox-coupled electroceutical wound dressing disrupts bacterial biofilm. PLoS One 2015; 10:e0119531. [PMID: 25803639 PMCID: PMC4372374 DOI: 10.1371/journal.pone.0119531] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 01/20/2015] [Indexed: 11/19/2022] Open
Abstract
Pseudomonas aeruginosa biofilm is commonly associated with chronic wound infection. A FDA approved wireless electroceutical dressing (WED), which in the presence of conductive wound exudate gets activated to generate electric field (0.3–0.9V), was investigated for its anti-biofilm properties. Growth of pathogenic P. aeruginosa strain PAO1 in LB media was markedly arrested in the presence of the WED. Scanning electron microscopy demonstrated that WED markedly disrupted biofilm integrity in a setting where silver dressing was ineffective. Biofilm thickness and number of live bacterial cells were decreased in the presence of WED. Quorum sensing genes lasR and rhlR and activity of electric field sensitive enzyme, glycerol-3-phosphate dehydrogenase was also repressed by WED. This work provides first electron paramagnetic resonance spectroscopy evidence demonstrating that WED serves as a spontaneous source of reactive oxygen species. Redox-sensitive multidrug efflux systems mexAB and mexEF were repressed by WED. Taken together, these observations provide first evidence supporting the anti-biofilm properties of WED.
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Inactivation of Dekkera bruxellensis yeasts in wine storage in brand new oak barrels using low electric current technology. ANN MICROBIOL 2015. [DOI: 10.1007/s13213-015-1047-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Stimulating sediment bioremediation with benthic microbial fuel cells. Biotechnol Adv 2015; 33:1-12. [DOI: 10.1016/j.biotechadv.2014.12.011] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 12/29/2014] [Accepted: 12/29/2014] [Indexed: 12/30/2022]
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Hosseini MR, Schaffie M, Pazouki M, Ranjbar M. DIRECT ELECTRIC CURRENT STIMULATION OF PROTEIN SECRETION BYFUSARIUM OXYSPORUM. CHEM ENG COMMUN 2013. [DOI: 10.1080/00986445.2013.764520] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Racyte J, Bernard S, Paulitsch-Fuchs AH, Yntema DR, Bruning H, Rijnaarts HHM. Alternating electric fields combined with activated carbon for disinfection of Gram negative and Gram positive bacteria in fluidized bed electrode system. WATER RESEARCH 2013; 47:6395-6405. [PMID: 24012021 DOI: 10.1016/j.watres.2013.08.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 05/24/2013] [Accepted: 08/07/2013] [Indexed: 06/02/2023]
Abstract
Strong electric fields for disinfection of wastewaters have been employed already for several decades. An innovative approach combining low strength (7 V/cm) alternating electric fields with a granular activated carbon fluidized bed electrode (FBE) for disinfection was presented recently. For disinfection performance of FBE several pure microbial cultures were tested: Bacillus subtilis, Bacillus subtilis subsp. subtilis, Enterococcus faecalis as representatives from Gram positive bacteria and Erwinia carotovora, Pseudomonas luteola, Pseudomonas fluorescens and Escherichia coli YMc10 as representatives from Gram negative bacteria. The alternating electric field amplitude and shape were kept constant. Only the effect of alternating electric field frequency on disinfection performance was investigated. From the bacteria tested, the Gram negative strains were more susceptible and the Gram positive microorganisms were more resistant to FBE disinfection. The collected data indicate that the efficiency of disinfection is frequency and strain dependent. During 6 h of disinfection, the decrease above 2 Log units was achieved with P. luteola and E. coli at 10 kHz and at dual frequency shift keying (FSK) modulated signal with frequencies of 10 kHz and 140 kHz. FBE technology appears to offer a new way for selective bacterial disinfection, however further optimizations are needed on treatment duration, and energy input, to improve effectiveness.
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Affiliation(s)
- Justina Racyte
- Wetsus, Centre of Excellence for Sustainable Water Technology, Agora 1, P.O. Box 1113, 8900 CC Leeuwarden, The Netherlands; Sub-Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
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Gomes MDN, Teixeira CAA, Barbosa GM, Froes MT, Silva MB, da Veiga VF, Soares RMDA, dos Santos ALS, Holandino C. Effects of direct electric current on Herpetomonas samuelpessoai: An ultrastructural study. Bioelectromagnetics 2011; 33:334-45. [DOI: 10.1002/bem.20712] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 09/18/2011] [Indexed: 01/28/2023]
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Velasco-Alvarez N, González I, Damian-Matsumura P, Gutiérrez-Rojas M. Enhanced hexadecane degradation and low biomass production by Aspergillus niger exposed to an electric current in a model system. BIORESOURCE TECHNOLOGY 2011; 102:1509-15. [PMID: 20739180 DOI: 10.1016/j.biortech.2010.07.111] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 07/27/2010] [Accepted: 07/28/2010] [Indexed: 05/15/2023]
Abstract
The effects of an electric current on growth and hexadecane (HXD) degradation by Aspergillus niger growth were determined. A 450-mL electrochemical cell with titanium ruthenium-oxide coated electrodes and packed with 15 g of perlite (inert biomass support) was inoculated with A. niger (2.0×10(7) spores (g of dry inert support)(-1)) and incubated for 12 days (30 °C; constant ventilation). 4.5 days after starting culture a current of 0.42 mA cm(-2) was applied for 24h. The current reduced (52±11%) growth of the culture as compared to that of a culture not exposed to current. However, HXD degradation was 96±1.4% after 8 days whereas it was 81±1.2% after 12 days in control cultures. Carbon balances of cultures not exposed to current suggested an assimilative metabolism, but a non-assimilative metabolism when the current was applied. This change can be related to an increase in total ATP content. The study contributes to the knowledge on the effects of current on the mycelial growth phase of A. niger, and suggests the possibility of manipulating the metabolism of this organism with electric current.
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Affiliation(s)
- Nancy Velasco-Alvarez
- Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, Iztapalapa 09340, DF, Mexico
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Podolska VI, Yakubenko LN, Ulberg ZR, Ermakov VN, Grischenko NI. Effect of weak pulse electric fields on surface properties and destructive activity of Pseudomonas bacteria. COLLOID JOURNAL 2010. [DOI: 10.1134/s1061933x10060153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Urbanus J, Bisselink R, Nijkamp K, ter Horst J, Verdoes D, Roelands C. Integrated product removal of slightly water-soluble carboxylates from fermentation by electrochemically induced crystallization. J Memb Sci 2010. [DOI: 10.1016/j.memsci.2010.07.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Podolska VI, Ermakov VN, Yakubenko LN, Ulberg ZR, Gryshchenko NI. Effect of Low-Intensity Pulsed Electric Fields on the Respiratory Activity and Electrosurface Properties of Bacteria. FOOD BIOPHYS 2009. [DOI: 10.1007/s11483-009-9126-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Weak electric currents generated using conductive electrodes have been shown to increase the efficacy of antibiotics against bacterial biofilms, a phenomenon termed "the bioelectric effect." The purposes of the present study were (i) to find out whether insulated electrodes that generate electric fields without "ohmic" electric currents, and thus are not associated with the formation of metal ions and free radicals, can inhibit the growth of planktonic bacteria and (ii) to define the parameters that are most effective against bacterial growth. The results obtained indicate that electric fields generated using insulated electrodes can inhibit the growth of planktonic Staphylococcus aureus and Pseudomonas aeruginosa and that the effect is amplitude and frequency dependent, with a maximum at 10 MHz. The combined effect of the electric field and chloramphenicol was found to be additive. Several possible mechanisms underlying the observed effect, as well as its potential clinical uses, are discussed.
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