1
|
Manfredini A, Malusà E, Pinzari F, Canfora L. Quantification of nitrogen cycle functional genes from viable archaea and bacteria in paddy soil. J Appl Microbiol 2023; 134:lxad169. [PMID: 37516446 DOI: 10.1093/jambio/lxad169] [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: 05/03/2023] [Revised: 07/24/2023] [Accepted: 07/28/2023] [Indexed: 07/31/2023]
Abstract
AIMS One of the main challenges of culture-independent soil microbiology is distinguishing the microbial community's viable fraction from dead matter. Propidium monoazide (PMA) binds the DNA of dead cells, preventing its amplification. This dye could represent a robust means to overcome the drawbacks of other selective methods, such as ribonucleic acid-based analyses. METHODS AND RESULTS We quantified functional genes from viable archaea and bacteria in soil by combining the use of PMA and quantitative polymerase chain reaction. Four N-cycle-related functional genes (bacterial and archaeal ammonia monooxygenase, nitrate reductase, and nitrite reductase) were successfully quantified from the living fraction of bacteria and archaea of a paddy soil. The protocol was also tested with pure bacterial cultures and soils with different physical and chemical properties. CONCLUSIONS The experiment results revealed a contrasting impact of mineral and organic fertilizers on the abundance of microbial genes related to the N-cycle in paddy soil.
Collapse
Affiliation(s)
- Andrea Manfredini
- Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment, 00184 Roma, Italy
| | - Eligio Malusà
- Council for Agricultural Research and Economics, Research Centre for Viticulture and Enology, 31015 Conegliano, Italy
- National Institute of Horticultural Research, 96-100 Skierniewice, Poland
| | - Flavia Pinzari
- Institute for Biological Systems, Council of National Research of Italy (CNR), 00010 Montelibretti, Italy
- Life Sciences Department, Natural History Museum, Cromwell Road, SW7 5BD London, UK
| | - Loredana Canfora
- Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment, 00184 Roma, Italy
| |
Collapse
|
2
|
Qin Y, Qu B, Lee B. Rapid Monitoring of Viable Genetically Modified Escherichia coli Using a Cell-Direct Quantitative PCR Method Combined with Propidium Monoazide Treatment. Microorganisms 2023; 11:1128. [PMID: 37317102 DOI: 10.3390/microorganisms11051128] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/18/2023] [Accepted: 04/24/2023] [Indexed: 06/16/2023] Open
Abstract
The commercialization of industrial genetically modified microorganisms (GMMs) has highlighted their impact on public health and the environment. Rapid and effective monitoring methods detecting live GMMs are essential to enhance current safety management protocols. This study aims to develop a novel cell-direct quantitative polymerase chain reaction (qPCR) method targeting two antibiotic-resistant genes, KmR and nptII, conferring resistance against kanamycin and neomycin, along with propidium monoazide, to precisely detect viable Escherichia coli. The E. coli single-copy taxon-specific gene of D-1-deoxyxylulose 5-phosphate synthase (dxs) was used as the internal control. The qPCR assays demonstrated good performance, with dual-plex primer/probe combinations exhibiting specificity, absence of matrix effects, linear dynamic ranges with acceptable amplification efficiencies, and repeatability for DNA, cells, and PMA-treated cells targeting KmR/dxs and nptII/dxs. Following the PMA-qPCR assays, the viable cell counts for KmR-resistant and nptII-resistant E. coli strains exhibited a bias% of 24.09% and 0.49%, respectively, which were within the acceptable limit of ±25%, as specified by the European Network of GMO Laboratories. This method successfully established detection limits of 69 and 67 viable genetically modified E. coli cells targeting KmR and nptII, respectively. This provides a feasible monitoring approach as an alternative to DNA processing techniques to detect viable GMMs.
Collapse
Affiliation(s)
- Yang Qin
- Department of Environment Science & Biotechnology, Jeonju University, Jeonju 55069, Republic of Korea
| | - Bo Qu
- Department of Environment Science & Biotechnology, Jeonju University, Jeonju 55069, Republic of Korea
| | - Bumkyu Lee
- Department of Environment Science & Biotechnology, Jeonju University, Jeonju 55069, Republic of Korea
| |
Collapse
|
3
|
Mazzantini D, Celandroni F, Calvigioni M, Panattoni A, Labella R, Ghelardi E. Microbiological Quality and Resistance to an Artificial Gut Environment of Two Probiotic Formulations. Foods 2021; 10:foods10112781. [PMID: 34829062 PMCID: PMC8617924 DOI: 10.3390/foods10112781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/18/2022] Open
Abstract
The quality control of probiotic products is the focus of numerous organizations worldwide. Several studies have highlighted the poor microbiological quality of many commercial probiotic formulations in terms of the identity of the contained microorganisms, viability, and purity, thus precluding the expected health benefits and representing a potential health risk for consumers. In this paper, we analyzed the contents of two probiotic formulations, one composed of an encapsulated mixture of lactobacilli and bifidobacteria, and one by a lyophilized yeast. The microorganisms contained in the products were quantified and identified using up-to-date methodologies, such as MALDI-TOF MS and metagenomic analysis. Moreover, as acid and bile tolerance is included among the criteria used to select probiotic microorganisms, in vitro tests were performed to evaluate the behavior of the formulations in conditions mimicking the harsh gastric environment and the intestinal fluids. Our results indicate the high quality of the formulations in terms of the enumeration and identification of the contained organisms, as well as the absence of contaminants. Moreover, both products tolerated the acidic conditions well, with encapsulation providing further protection for the microorganisms. A good tolerance to the simulated artificial intestinal conditions was also evidenced for both preparations.
Collapse
Affiliation(s)
- Diletta Mazzantini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno 37, 56127 Pisa, Italy; (D.M.); (F.C.); (M.C.); (A.P.)
| | - Francesco Celandroni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno 37, 56127 Pisa, Italy; (D.M.); (F.C.); (M.C.); (A.P.)
| | - Marco Calvigioni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno 37, 56127 Pisa, Italy; (D.M.); (F.C.); (M.C.); (A.P.)
| | - Adelaide Panattoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno 37, 56127 Pisa, Italy; (D.M.); (F.C.); (M.C.); (A.P.)
| | - Roberto Labella
- Sanofi Consumer Health Care, Reading, Berkshire RG6 1PT, UK;
| | - Emilia Ghelardi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno 37, 56127 Pisa, Italy; (D.M.); (F.C.); (M.C.); (A.P.)
- Research Center Nutraceuticals and Food for Health-Nutrafood, University of Pisa, 56127 Pisa, Italy
- Correspondence: ; Tel.: +39-050-221-3679
| |
Collapse
|
4
|
Mazzantini D, Calvigioni M, Celandroni F, Lupetti A, Ghelardi E. Spotlight on the Compositional Quality of Probiotic Formulations Marketed Worldwide. Front Microbiol 2021; 12:693973. [PMID: 34354690 PMCID: PMC8329331 DOI: 10.3389/fmicb.2021.693973] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/29/2021] [Indexed: 11/13/2022] Open
Abstract
On the worldwide market, a great number of probiotic formulations are available to consumers as drugs, dietary supplements, and functional foods. For exerting their beneficial effects on host health, these preparations should contain a sufficient amount of the indicated living microbes and be pathogen-free to be safe. Therefore, the contained microbial species and their amount until product expiry are required to be accurately reported on the labels. While commercial formulations licensed as drugs are subjected to rigorous quality controls, less stringent regulations are generally applied to preparations categorized as dietary supplements and functional foods. Many reports indicated that the content of several probiotic formulations does not always correspond to the label claims in terms of microbial identification, number of living organisms, and purity, highlighting the requirement for more stringent quality controls by manufacturers. The main focus of this review is to provide an in-depth overview of the microbiological quality of probiotic formulations commercialized worldwide. Many incongruences in the compositional quality of some probiotic formulations available on the worldwide market were highlighted. Even if manufacturers carry at least some of the responsibility for these inconsistencies, studies that analyze probiotic products should be conducted following recommended and up-to-date methodologies.
Collapse
Affiliation(s)
- Diletta Mazzantini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Marco Calvigioni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Francesco Celandroni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Antonella Lupetti
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Emilia Ghelardi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,Research Center Nutraceuticals and Food for Health-Nutrafood, University of Pisa, Pisa, Italy
| |
Collapse
|
5
|
Tut G, Magan N, Brain P, Xu X. Molecular Assay Development to Monitor the Kinetics of Viable Populations of Two Biocontrol Agents, Bacillus subtilis QST 713 and Gliocladium catenulatum J1446, in the Phyllosphere of Lettuce Leaves. Biology (Basel) 2021; 10:biology10030224. [PMID: 33804029 PMCID: PMC8001495 DOI: 10.3390/biology10030224] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/08/2021] [Accepted: 03/10/2021] [Indexed: 11/19/2022]
Abstract
Simple Summary There is a need to be able to track the viable populations of biocontrol agents when applied on the foliar surfaces of plants. We have developed a molecular-based method for the quantification of viable cells of two commercial biocontrol agents—a bacterium (Bacillus subtilis) and a fungus (Gliocladium catenulatum). The method has been tested on the leaf surfaces of lettuce plants to examine the changes in viable population over 10–12 days for the first time. Abstract Optimising the use of biocontrol agents (BCAs) requires the temporal tracking of viable populations in the crop phyllosphere to ensure that effective control can be achieved. No sensitive systems for quantifying viable populations of commercially available BCAs, such as Bacillus subtilis and Gliocladium catenulatum, in the phyllosphere of crop plants are available. The objective of this study was to develop a method to quantify viable populations of these two BCAs in the crop phyllosphere. A molecular tool based on propidium monoazide (PMA) (PMAxx™-qPCR) capable of quantifying viable populations of these two BCAs was developed. Samples were treated with PMAxx™ (12.5–100 μM), followed by 15 min incubation, exposure to a 800 W halogen light for 30 min, DNA extraction, and quantification using qPCR. This provided a platform for using the PMAxx™-qPCR technique for both BCAs to differentiate viable from dead cells. The maximum number of dead cells blocked, based on the DNA, was 3.44 log10 for B. subtilis and 5.75 log10 for G. catenulatum. Validation studies showed that this allowed accurate quantification of viable cells. This method provided effective quantification of the temporal changes in viable populations of the BCAs in commercial formulations on lettuce leaves in polytunnel and glasshouse production systems.
Collapse
Affiliation(s)
- Gurkan Tut
- NIAB East Malling Research, West Malling, Kent ME19 6BJ, UK; (G.T.); (P.B.); (X.X.)
- Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Bedford MK43 0AL, UK
| | - Naresh Magan
- Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Bedford MK43 0AL, UK
- Correspondence:
| | - Philip Brain
- NIAB East Malling Research, West Malling, Kent ME19 6BJ, UK; (G.T.); (P.B.); (X.X.)
| | - Xiangming Xu
- NIAB East Malling Research, West Malling, Kent ME19 6BJ, UK; (G.T.); (P.B.); (X.X.)
| |
Collapse
|
6
|
Beinhauerova M, Slana I. Phage Amplification Assay for Detection of Mycobacterial Infection: A Review. Microorganisms 2021; 9:237. [PMID: 33498792 DOI: 10.3390/microorganisms9020237] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/28/2022] Open
Abstract
An important prerequisite for the effective control, timely diagnosis, and successful treatment of mycobacterial infections in both humans and animals is a rapid, specific, and sensitive detection technique. Culture is still considered the gold standard in the detection of viable mycobacteria; however, mycobacteria are extremely fastidious and slow-growing microorganisms, and therefore cultivation requires a very long incubation period to obtain results. Polymerase Chain Reaction (PCR) methods are also frequently used in the diagnosis of mycobacterial infections, providing faster and more accurate results, but are unable to distinguish between a viable and non-viable microorganism, which results in an inability to determine the success of tuberculosis patient treatment or to differentiate between an active and passive infection of animals. One suitable technique that overcomes these shortcomings mentioned is the phage amplification assay (PA). PA specifically detects viable mycobacteria present in a sample within 48 h using a lytic bacteriophage isolated from the environment. Nowadays, an alternative approach to PA, a commercial kit called Actiphage™, is also employed, providing the result within 6–8 h. In this approach, the bacteriophage is used to lyse mycobacterial cells present in the sample, and the released DNA is subsequently detected by PCR. The objective of this review is to summarize information based on the PA used for detection of mycobacteria significant in both human and veterinary medicine from various kinds of matrices.
Collapse
|
7
|
Bampidis V, Azimonti G, Bastos MDL, Christensen H, Dusemund B, Durjava MF, Kouba M, López‐Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M, Ramos F, Sanz Y, Villa RE, Woutersen R, Cocconcelli PS, Glandorf B, Herman L, Maradona MP, Saarela M, Anguita M, Galobart J, Holczkencht O, Manini P, Pettenati E, Pizzo F, Tarrés‐Call J. Safety and efficacy of l-lysine monohydrochloride and concentrated liquid l-lysine (base) produced by fermentation with Corynebacterium glutamicumKCTC 12307BP as feed additives for all animal species. EFSA J 2020; 18:e06333. [PMID: 33391396 PMCID: PMC7771263 DOI: 10.2903/j.efsa.2020.6333] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety for the target animals, consumer, user and the environment and on the efficacy of a concentrated liquid l-lysine (base, minimum 50%) and a l-lysine monohydrochloride (HCl, minimum 99%) produced by fermentation with a genetically modified strain of Corynebacterium glutamicum (KCTC 12307BP). Both forms of l-lysine are intended to be used in feed for all animal species and categories. Neither the production strain nor its recombinant DNA were detected in the final products. The additives do not pose any safety concern associated with the genetic modification of the production strain. Concentrated liquid l-lysine (base) and l-lysine HCl produced by the strain C. glutamicum KCTC 12307BP do not represent a risk for the target species, for the consumer, for the user and for the environment. l-Lysine HCl and concentrated liquid l-lysine (base) are considered to be efficacious sources of the essential amino acid l-lysine for non-ruminant animal species. For the supplemental l-lysine to be as efficacious in ruminants as in non-ruminant species, it would require protection against degradation in the rumen.
Collapse
|
8
|
Fu Y, Ye Z, Jia Y, Fan J, Hashmi MZ, Shen C. An Optimized Method to Assess Viable Escherichia coli O157:H7 in Agricultural Soil Using Combined Propidium Monoazide Staining and Quantitative PCR. Front Microbiol 2020; 11:1809. [PMID: 32849416 PMCID: PMC7411311 DOI: 10.3389/fmicb.2020.01809] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 07/09/2020] [Indexed: 11/29/2022] Open
Abstract
Agricultural soil contaminated by manure is becoming an important source for the transmission of foodborne pathogens. There is an urgent need for a rapid and accurate method for viable pathogen detection in agricultural soil samples. Propidium monoazide (PMA) is a DNA-binding dye that can inhibit the amplification of DNA from dead cells through subsequent quantitative polymerase chain reaction (qPCR), thus allowing for viable cells detection and quantification. The objective of this study was to detect viable Escherichia coli O157:H7 in the agricultural soils by PMA-qPCR. In this study, cell extraction and gradient density centrifugation were incorporated before PMA-qPCR to reduce the interference of soil particle including turbidity and a high ratio of dead cells. The optimized treatment conditions were determined as follows, the maximum removal of DNA from dead cells was achieved by 1.067 g/mL Percoll of centrifugation and 50 μM PMA treatment. Under these conditions, the turbidity of paddy soil suspensions decreased from 3500 to 28.4 nephelometric turbidity units (NTU), and the ratio of viable cells to dead cells increased from 0.001 to 1.025%. For typical agricultural soils collected in China, as low as 102colony-forming units (CFU)/g of viable cells could be accurately detected in the presence of a large number of dead cells (107 CFU/g) by the optimized PMA-qPCR. Significantly, with comparable accuracy, the optimized PMA-qPCR assay was more sensitive, accessible and rapid than conventional culture methods. In addition, the viable but non-culturable (VBNC) state of E. coli O157:H7 cells in paddy soils, which often escaped the detection by conventional culture methods, could be quantitatively characterized by the optimized PMA-qPCR method. Potentially, the optimized PMA-qPCR can be further applied for viable pathogens detection and give insight into the prevalence of VBNC E. coli O157:H7 in agricultural soil.
Collapse
Affiliation(s)
- Yulong Fu
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Zhe Ye
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Yangyang Jia
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Jiahui Fan
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | | | - Chaofeng Shen
- Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, China
| |
Collapse
|
9
|
Mfarrej B, Gaude J, Couquiaud J, Calmels B, Chabannon C, Lemarie C. Validation of a flow cytometry-based method to quantify viable lymphocyte subtypes in fresh and cryopreserved hematopoietic cellular products. Cytotherapy 2020; 23:77-87. [PMID: 32718876 DOI: 10.1016/j.jcyt.2020.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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: 05/04/2020] [Revised: 05/27/2020] [Accepted: 06/22/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND AIMS Adoptive cellular therapy with immune effector cells (IECs) has shown promising efficacy against some neoplastic diseases as well as potential in immune regulation. Both inherent variability in starting material and variations in cell composition produced by the manufacturing process must be thoroughly evaluated with a validated method established to quantify viable lymphocyte subtypes. Currently, commercialized immunophenotyping methods determine cell viability with significant errors in thawed products since they do not include any viability staining. We hereby report on the validation of a flow cytometry-based method for quantifying viable lymphocyte immunophenotypes in fresh and cryopreserved hematopoietic cellular products. METHODS Using fresh or frozen cellular products and stabilized blood, we report on the validation parameters accuracy, uncertainty, precision, sensitivity, robustness and contamination between samples for quantification of viable CD3+, CD4+ T cells, CD8+ T cells, CD3-CD56+CD16+/- NK cells, CD19+ B cells and CD14+ monocytes of relevance to fresh and cryopreserved hematopoietic cellular products using the Cytomics FC500 cytometer (Beckman Coulter). RESULTS The acceptance criteria set in the validation plan were all met. The method is able to accommodate the variability in absolute numbers of cells in starting materials collected or cryopreserved from patients or healthy donors (uncertainty of ≤20% at three different concentrations), stability over time (compliance over 3 years during regular inter-laboratory comparisons) and confidence in meaningful changes during cell processing and manufacturing (intra-assay and intermediate precision of 10% coefficient of variation). Furthermore, the method can accurately report on the efficacy of cell depletion since the lower limit of quantification was established (CD3+, CD4+ and CD8+ cells at 9, 8 and 8 cells/µL, respectively). The method complies with Foundation for the Accreditation of Cellular Therapy (FACT) standards for IEC, FACT-Joint Accreditation Committee of ISCT-EBMT (JACIE) hematopoietic cell therapy standards, International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use Q2(R1) and International Organization for Standardization 15189 standards. Furthermore, it complies with Ligand Binding Assay Bioanalytical Focus Group/American Association of Pharmaceutical Scientists, International Council for Standardization of Hematology/International Clinical Cytometry Society and European Bioanalysis Forum recommendations for validating such methods. CONCLUSIONS The implications of this effort include standardization of viable cell immunophenotyping of starting material for cell manufacturing, cell selection and in-process quality controls or dosing of IECs. This method also complies with all relevant standards, particularly FACT-JACIE standards, in terms of enumerating and reporting on the viability of the "clinically relevant cell populations."
Collapse
Affiliation(s)
- Bechara Mfarrej
- Centre de Thérapie Cellulaire, Institut Paoli-Calmettes, Marseille, France.
| | - Julie Gaude
- Centre de Thérapie Cellulaire, Institut Paoli-Calmettes, Marseille, France
| | - Jerome Couquiaud
- Centre de Thérapie Cellulaire, Institut Paoli-Calmettes, Marseille, France
| | - Boris Calmels
- Centre de Thérapie Cellulaire, Institut Paoli-Calmettes, Marseille, France
| | | | - Claude Lemarie
- Centre de Thérapie Cellulaire, Institut Paoli-Calmettes, Marseille, France
| |
Collapse
|
10
|
Hazeem LJ, Kuku G, Dewailly E, Slomianny C, Barras A, Hamdi A, Boukherroub R, Culha M, Bououdina M. Toxicity Effect of Silver Nanoparticles on Photosynthetic Pigment Content, Growth, ROS Production and Ultrastructural Changes of Microalgae Chlorella vulgaris. Nanomaterials (Basel) 2019; 9:nano9070914. [PMID: 31247939 PMCID: PMC6669524 DOI: 10.3390/nano9070914] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 06/18/2019] [Accepted: 06/20/2019] [Indexed: 11/16/2022]
Abstract
Silver nanoparticles (Ag NPs) exhibit antibacterial activity and are extensively used in numerous applications. The aim of this study was to examine the toxic effect of Ag NPs on the marine microalga, Chlorella vulgaris. The microalgae, at the exponential growth phase, were treated with different concentrations of Ag NPs (50 and 100 nm) for 96 h. X-Ray diffraction (XRD) results indicated that the used NPs are single and pure Ag phase with a mean crystallite size of 21 and 32 nm. Ag NPs were found to have a negative effect on viable cell concentration, a variable effect on chlorophyll a concentration, and increased ROS formation. Transmission electron microscopy (TEM) analysis revealed that Ag NPs were present inside the microalgae cells and formed large aggregates in the culture medium. Ag+ ions, in the form of AgNO3, were also assessed at higher concentrations and found to cause inhibitory effects.
Collapse
Affiliation(s)
- Layla J Hazeem
- Department of Biology, College of Science, University of Bahrain, P.O. Box 32038, Zallaq 1054, Bahrain
| | - Gamze Kuku
- Department of Genetics and Bioengineering, Yeditepe University, Atasehir 34755, Istanbul, Turkey.
| | - Etienne Dewailly
- Laboratoire de Physiologie Cellulaire, INSERM U.1003, Université de Lille, Rue Paul Langevin, 59655 Villeneuve d'Ascq, France
| | - Christian Slomianny
- Laboratoire de Physiologie Cellulaire, INSERM U.1003, Université de Lille, Rue Paul Langevin, 59655 Villeneuve d'Ascq, France
| | - Alexandre Barras
- Univ. Lille, CNRS, Centrale Lille, ISEN, Univ. Valenciennes, UMR 8520-IEMN, F-59000 Lille, France
| | - Abderrahmane Hamdi
- Univ. Lille, CNRS, Centrale Lille, ISEN, Univ. Valenciennes, UMR 8520-IEMN, F-59000 Lille, France
| | - Rabah Boukherroub
- Univ. Lille, CNRS, Centrale Lille, ISEN, Univ. Valenciennes, UMR 8520-IEMN, F-59000 Lille, France
| | - Mustafa Culha
- Department of Genetics and Bioengineering, Yeditepe University, Atasehir 34755, Istanbul, Turkey
| | - Mohamed Bououdina
- Department of Physics, College of Science, University of Bahrain, P.O. Box 32038, Zallaq 1054, Bahrain
| |
Collapse
|
11
|
Jairaman C, Yacoob SAM, Venkatraman A, Nagarajan Y, Murugesan G. Propugnating Effect of Bark of Rhizophora mucronata Against Different Toxicants Viz Carbon Tetrachloride, Ethanol and Paracetamol on HepG 2 Cell Lines. J Pharmacopuncture 2019; 22:41-48. [PMID: 30989000 PMCID: PMC6461297 DOI: 10.3831/kpi.2019.22.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/08/2019] [Accepted: 02/11/2019] [Indexed: 11/09/2022] Open
Abstract
Objective The aim of the study was to evaluate the hepatoprotective activity of the bark extract (Ethanol: Water) in the ratio of (3:1) of Rhizophora mucronata (BERM) by intoxicating the HepG2 cell lines with different toxicants viz, CCL4, Ethanol and Paracetamol with different concentrations of the extract were used. The HepG2 cell lines were subjected to MTT Assay for studying the cytotoxicity. Methods HepG2 cells were plated using 96 well plate in 10% bovine serum, exposed to different toxicants viz, 2% CCl4, 60% Ethanol and 14 mM Paracetamol respectively. The various test concentrations (18.85, 37.5, 75, 150 and 300 μg/ml) of bark extract of Rhizophora mucronata was added and incubated for 24 hours. Medium was removed after incubation period and 0.5 mg/ml MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) was added and again incubated for 4 hours at 37oC. Then MTT was removed the crystals was dissolved in DMSO and absorbance was measured at 570 nm. Results The result showed that dose dependent increase in percentage of viability at the doses of 18.85, 37.5, 75, 150, 300 μg/ml. The results for the CCl4 intoxicated, at 300 μg/ml of the concentration of the extract, the % of viable cells was found out to be 99.6%, for Ethanol intoxicated, 97.67%, and Paracetamol induced, 75.37%, IC50 was 21.53 μg/ml, 12.61 μg/ml and 21.42 μg/ml respectively. Conclusion Thus, we conclude that, the extract possesses defensive effect against different toxicants and can be used as an alternate drug for hepatotoxicity.
Collapse
Affiliation(s)
- Chitra Jairaman
- PG and Research Department of Biotechnology, Mohammed Sathak College of Arts & Science, Shollinganallur, Chennai-119, Tamil nadu, India
| | - Syed Ali Mohamed Yacoob
- PG and Research Department of Biotechnology, Mohammed Sathak College of Arts & Science, Shollinganallur, Chennai-119, Tamil nadu, India
| | - Anuradha Venkatraman
- PG and Research Department of Biochemistry, Mohammed Sathak College of Arts & Science, Shollinganallur, Chennai-119, Tamil nadu, India
| | - Yogananth Nagarajan
- PG and Research Department of Biotechnology, Mohammed Sathak College of Arts & Science, Shollinganallur, Chennai-119, Tamil nadu, India
| | - Gnanadesigan Murugesan
- Department of Microbial Biotechnology, Bharathair University, Coimbatore-641046, Tamil nadu, India
| |
Collapse
|
12
|
Salas-Massó N, Linh QT, Chin WH, Wolff A, Andree KB, Furones MD, Figueras MJ, Bang DD. The Use of a DNA-Intercalating Dye for Quantitative Detection of Viable Arcobacter spp. Cells (v-qPCR) in Shellfish. Front Microbiol 2019; 10:368. [PMID: 30873146 PMCID: PMC6403187 DOI: 10.3389/fmicb.2019.00368] [Citation(s) in RCA: 10] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 02/12/2019] [Indexed: 11/13/2022] Open
Abstract
The genus Arcobacter (Vandamme et al., 1991), comprised of Campylobacter-related species, are considered zoonotic emergent pathogens. The presence of Arcobacter in food products like shellfish, has an elevated incidence worldwide. In this study, we developed a specific viable quantitative PCR (v-qPCR), using the dye propidium monoazide (PMA), for quantification of the viable Arcobacter spp. cells in raw oysters and mussels. The high selectivity of primers was demonstrated by using purified DNA from 38 different species, 20 of them from the genus Arcobacter. The optimization of PMA concentration showed that 20 μM was considered as an optimal concentration that inhibits the signal from dead cells at different concentrations (OD550 from 0.2 to 0.8) and at different ratios of live: dead cells (50:50 and 90:10). The v-qPCR results from shellfish samples were compared with those obtained in parallel using several culture isolation approaches (i.e., direct plating on marine and blood agar and by post-enrichment culturing in both media). The enrichment was performed in parallel in Arcobacter-CAT broth with and without adding NaCl. Additionally, the v-qPCR results were compared to those obtained with traditional quantitative (qPCR). The v-qPCR and the qPCR resulted in c.a. 94% of positive detection of Arcobacter vs. 41% obtained by culture approaches. When examining the reduction effect resulting from the use of v-qPCR, samples pre-enriched in Arcobacter-CAT broth supplemented with 2.5% NaCl showed a higher reduction (3.27 log copies) than that of samples obtained directly and those pre-enriched in Arcobacter-CAT broth isolation (1.05 and 1.04). When the v-qPCR was applied to detect arcobacter from real shellfish samples, 15/17 samples tested positive for viable Arcobacter with 3.41 to 8.70 log copies 1g-1. This study offers a new tool for Arcobacter surveillance in seafood.
Collapse
Affiliation(s)
- Nuria Salas-Massó
- Unitat de Microbiologia, Departament de Ciènces Médiques Bàsiques, Facultat de Medicina i Ciències de la Salut, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Spain.,IRTA-Sant Carles de la Ràpita, Sant Carles de la Ràpita, Spain
| | - Quyen Than Linh
- Department of Bioengineering and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | | | - Anders Wolff
- Department of Bioengineering and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Karl B Andree
- IRTA-Sant Carles de la Ràpita, Sant Carles de la Ràpita, Spain
| | | | - María José Figueras
- Unitat de Microbiologia, Departament de Ciènces Médiques Bàsiques, Facultat de Medicina i Ciències de la Salut, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Spain
| | - Dang Duong Bang
- Division of Microbiology, National Food Institute, Technical University of Denmark, Lyngby, Denmark
| |
Collapse
|
13
|
Lopez-Fernandez M, Broman E, Turner S, Wu X, Bertilsson S, Dopson M. Investigation of viable taxa in the deep terrestrial biosphere suggests high rates of nutrient recycling. FEMS Microbiol Ecol 2018; 94:5040220. [PMID: 29931252 PMCID: PMC6030916 DOI: 10.1093/femsec/fiy121] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/15/2018] [Indexed: 11/14/2022] Open
Abstract
The deep biosphere is the largest 'bioreactor' on earth, and microbes inhabiting this biome profoundly influence global nutrient and energy cycles. An important question for deep biosphere microbiology is whether or not specific populations are viable. To address this, we used quantitative PCR and high throughput 16S rRNA gene sequencing of total and viable cells (i.e. with an intact cellular membrane) from three groundwaters with different ages and chemical constituents. There were no statistically significant differences in 16S rRNA gene abundances and microbial diversity between total and viable communities. This suggests that populations were adapted to prevailing oligotrophic conditions and that non-viable cells are rapidly degraded and recycled into new biomass. With higher concentrations of organic carbon, the modern marine and undefined mixed waters hosted a community with a larger range of predicted growth strategies than the ultra-oligotrophic old saline water. These strategies included fermentative and potentially symbiotic lifestyles by candidate phyla that typically have streamlined genomes. In contrast, the old saline waters had more 16S rRNA gene sequences in previously cultured lineages able to oxidize hydrogen and fix carbon dioxide. This matches the paradigm of a hydrogen and carbon dioxide-fed chemolithoautotrophic deep biosphere.
Collapse
Affiliation(s)
- Margarita Lopez-Fernandez
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Barlastgatan 11, Kalmar, Sweden
| | - Elias Broman
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Barlastgatan 11, Kalmar, Sweden
| | - Stephanie Turner
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Barlastgatan 11, Kalmar, Sweden
| | - Xiaofen Wu
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Barlastgatan 11, Kalmar, Sweden
| | - Stefan Bertilsson
- Department of Ecology and Genetics, Limnology and Science for Life Laboratory, Uppsala University, Norbyvägen 18D, Uppsala, Sweden
| | - Mark Dopson
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Barlastgatan 11, Kalmar, Sweden
| |
Collapse
|
14
|
Lepekhova SA, Goldberg OA, Kravchenko AA, Batraks AE, Koval EV, Kurgansky IS, Apartsin KA. A Method for Microencapsulation of Cells and a Device for Its Realization. Bull Exp Biol Med 2017; 162:820-823. [PMID: 28429231 DOI: 10.1007/s10517-017-3721-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Indexed: 10/19/2022]
Abstract
The device for cell encapsulation makes it possible to fabricate microcapsules of a preset size with even smooth surface, without defects or adhesion to each other, with viable cells inside the capsule. The cells were derived from newborn piglet pancreases.
Collapse
Affiliation(s)
- S A Lepekhova
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia. .,Irkutsk Research Center, Siberian Division of the Russian Academy of Sciences, Irkutsk, Russia. .,Irkutsk State Medical University, Ministry of Health of the Russian Federation, Irkutsk, Russia.
| | - O A Goldberg
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - A A Kravchenko
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - A E Batraks
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - E V Koval
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - I S Kurgansky
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia
| | - K A Apartsin
- Irkutsk Research Center of Surgery and Traumatology, Irkutsk, Russia.,Irkutsk Research Center, Siberian Division of the Russian Academy of Sciences, Irkutsk, Russia.,Irkutsk State Medical University, Ministry of Health of the Russian Federation, Irkutsk, Russia
| |
Collapse
|
15
|
Yang X, Liu S, Li S, Wang P, Zhu W, Liang P, Tan J, Cui S. Salvianolic acid B regulates gene expression and promotes cell viability in chondrocytes. J Cell Mol Med 2017; 21:1835-1847. [PMID: 28244648 PMCID: PMC5571559 DOI: 10.1111/jcmm.13104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 12/28/2016] [Indexed: 11/27/2022] Open
Abstract
Articular chondrocytes reside in lacunae distributed in cartilage responsible for the remodelling of the tissue with limited ability of damage repairing. The in vitro expanded chondrocytes enhanced by factors/agents to obtain large numbers of cells with strengthened phenotype are essential for successful repair of cartilage lesions by clinical cell implantation therapies. Because the salvianolic acid B (Sal B), a major hydrophilic therapeutic agent isolated from Salvia miltiorrhiza, has been widely used to treat diseases and able to stimulate activity of cells, this study examines the effects of Sal B on passaged chondrocytes. Chondrocytes were treated with various concentrations of Sal B in monolayer culture, their morphological properties and changes, and mitochondrial membrane potential were analysed using microscopic analyses, including cellular biochemical staining and confocal laser scanning microscopy. The proteins were quantified by BCA and Western blotting, and the transcription of genes was detected by qRT‐PCR. The passaged chondrocytes treated with Sal B showed strengthened cellular synthesis and stabilized mitochondrial membrane potential with upregulated expression of the marker genes for chondrocyte phenotype, Col2‐α1, Acan and Sox9, the key Wnt signalling molecule β‐catenin and paracrine cytokine Cytl‐1. The treatments using CYTL‐1 protein significantly increased expression of Col2‐α1 and Acan with no effect on Sox9, indicating the paracrine cytokine acts on chondrocytes independent of SOX9. Sal B has ultimately promoted cell growth and enhanced chondrocyte phenotype. The chondrocytes treated with pharmaceutical agent and cytokine in the formulated medium for generating large number of differentiated chondrocytes would facilitate the cell‐based therapies for cartilage repair.
Collapse
Affiliation(s)
- Xiaohong Yang
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Shaojie Liu
- Department of General Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Siming Li
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Pengzhen Wang
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Weicong Zhu
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Peihong Liang
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Jianrong Tan
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China
| | - Shuliang Cui
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital, Jinan University School of Medicine, Guangzhou, China.,Department of Zoology, Faculty of Science, the University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
16
|
Wang Y, Yang M, Liu S, Chen W, Suo B. Detection of viable Salmonella in ice cream by TaqMan real-time polymerase chain reaction assay combining propidium monoazide. J Food Drug Anal 2015; 23:480-485. [PMID: 28911706 PMCID: PMC9351810 DOI: 10.1016/j.jfda.2015.03.002] [Citation(s) in RCA: 3] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 02/13/2015] [Accepted: 03/30/2015] [Indexed: 12/02/2022] Open
Abstract
Real-time polymerase chain reaction (PCR) allows rapid detection of Salmonella in frozen dairy products, but it might cause a false positive detection result because it might amplify DNA from dead target cells as well. In this study, Salmonella-free frozen ice cream was initially inoculated with heat-killed Salmonella Typhimurium cells and stored at −18°C. Bacterial DNA extracted from the sample was amplified using TaqMan probe-based real-time PCR targeting the invA gene. Our results indicated that DNA from the dead cells remained stable in frozen ice cream for at least 20 days, and could produce fluorescence signal for real-time PCR as well. To overcome this limitation, propidium monoazide (PMA) was combined with real-time PCR. PMA treatment can effectively prevent PCR amplification from heat-killed Salmonella cells in frozen ice cream. The PMA real-time PCR assay can selectively detect viable Salmonella at as low as 103 CFU/mL. Combining 18 hours of pre-enrichment with the assay allows for the detection of viable Salmonella at 100 CFU/mL and avoiding the false-positive result of dead cells. The PMA real-time PCR assay provides an alternative specifically for detection of viable Salmonella in ice cream. However, when the PMA real-time PCR assay was evaluated in ice cream subjected to frozen storage, it obviously underestimated the contamination situation of viable Salmonella, which might lead to a false negative result. According to this result, the use of enrichment prior to PMA real-time PCR analysis remains as the more appropriate approach.
Collapse
Affiliation(s)
- Yuexia Wang
- State Key Laboratory of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Synergetic Innovation Center of Food Safety and Nutrition, 1518 West Jiangchang Road, Shanghai 200436, China; College of Life Sciences, Henan Agricultural University, 63 Nongye Road, Zhengzhou, Henan 450002, China
| | - Ming Yang
- College of Life Sciences, Henan Agricultural University, 63 Nongye Road, Zhengzhou, Henan 450002, China
| | - Shuchun Liu
- College of Life Sciences, Henan Agricultural University, 63 Nongye Road, Zhengzhou, Henan 450002, China
| | - Wanyi Chen
- State Key Laboratory of Dairy Biotechnology, Dairy Research Institute, Bright Dairy & Food Co., Ltd., Synergetic Innovation Center of Food Safety and Nutrition, 1518 West Jiangchang Road, Shanghai 200436, China
| | - Biao Suo
- College of Food Science and Technology, Henan Agricultural University, 63 Nongye Road, Zhengzhou, Henan 450002, China.
| |
Collapse
|
17
|
Santos MI, Araujo-Andrade C, Esparza-Ibarra E, Tymczyszyn E, Gómez-Zavaglia A. Galacto-oligosaccharides and lactulose as protectants against desiccation of Lactobacillus delbrueckii subsp. bulcaricus. Biotechnol Prog 2014; 30:1231-8. [PMID: 25098896 DOI: 10.1002/btpr.1969] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [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: 03/02/2014] [Revised: 07/01/2014] [Indexed: 11/06/2022]
Abstract
Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333 was dehydrated on desiccators containing silica gel in the presence of 20% w/w of two types of galacto-oligosaccharides (GOS Biotempo and GOS Cup Oligo H-70®) and lactulose, until no changes in water desorption were detected. After rehydration, bacterial growth was monitored at 37°C by determining: (a) the absorbance at 600 nm and (b) the near infrared spectra (NIR). Principal component analysis (PCA) was then performed on the NIR spectra of samples dehydrated in all conditions. A multiparametric flow cytometry assay was carried out using carboxyfluorescein diacetate and propidium iodide probes to determine the relative composition of damaged, viable, and dead bacteria throughout the growth kinetics. The absorbance at 600 nm and the position of the second derivative band at ∼1370 nm were plotted against the time of incubation. The efficiency of the protectants was GOS Biotempo > GOS Cup Oligo H-70® > lactulose. The better protectant capacity of GOS Biotempo was explained on the basis of the lower contribution of damaged cells immediately after rehydration (t = 0). PCA showed three groups along PC1, corresponding to the lag, exponential and stationary phases of growth, which explained 99% of the total variance. Along PC2, two groups were observed, corresponding to damaged or viable cells. The results obtained support the use of NIR to monitor the recovery of desiccated microorganisms in real time and without the need of chemical reagents. The use of GOS and lactulose as protectants in dehydration/rehydration processes was also supported.
Collapse
Affiliation(s)
- Mauricio I Santos
- Center for Research and Development in Food Cryotechnology (CCT-CONICET La Plata), RA, 1900, Argentina
| | | | | | | | | |
Collapse
|