Cargando…
Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation
This study has characterized the dominant non-starter Lactobacillus species isolated from different sites in a Stilton cheese to establish its diversity, stress-tolerance, anti-microbial activity and potential contribution to quality of cheese. Fifty-nine Lactobacillus isolates were cultured from th...
Autores principales: | , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Media S.A.
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7236593/ https://www.ncbi.nlm.nih.gov/pubmed/32477308 http://dx.doi.org/10.3389/fmicb.2020.00904 |
_version_ | 1783536182631596032 |
---|---|
author | Mugampoza, Diriisa Gkatzionis, Konstantinos Swift, Benjamin M. C. Rees, Catherine E. D. Dodd, Christine E. R. |
author_facet | Mugampoza, Diriisa Gkatzionis, Konstantinos Swift, Benjamin M. C. Rees, Catherine E. D. Dodd, Christine E. R. |
author_sort | Mugampoza, Diriisa |
collection | PubMed |
description | This study has characterized the dominant non-starter Lactobacillus species isolated from different sites in a Stilton cheese to establish its diversity, stress-tolerance, anti-microbial activity and potential contribution to quality of cheese. Fifty-nine Lactobacillus isolates were cultured from the outer crust, blue veins and white core of the cheese and were speciated phenotypically and by 16S rDNA sequence analysis. Lactobacillus plantarum was the dominant species detected with only two isolates identified as Lactobacillus brevis. Strains were typed by pulse-field gel electrophoresis (PFGE) using the enzyme NotI to examine their genomic diversity. Cluster analysis of PFGE patterns produced five major clusters which associated isolates with their sites of isolation within the cheese. One L. plantarum isolate from each cheese site was selected and evaluated for salt, acid, relative humidity, and heat tolerance to determine whether stress conditions within the isolation site selected their phenotype. D(72°C) values were 6, 13, and 17 s for strains from the crust, veins and core, respectively, suggesting strains on the crust may not have been able to survive pasteurization and therefore had been added post-pasteurization. All strains recovered from heat injury within 24–48 h at 4°C. pH values of 3, 3.5, and 4 suppressed growth but strains showed a varying ability to grow at pH 4.5 and 5; isolates from the core (which has the lowest pH) were the most acid-tolerant. All strains grew at 3.5 and 5% salt but were suppressed at 10%; those from the crust (which has a lower water activity) were the most halo-tolerant, growing at 8% salt whereas strains from the core were sensitive to this salt concentration. All 57 L. plantarum isolates were examined for antimicrobial activity and variable activity against Lactobacillus pentosus and other genera was demonstrated; plantaricin EF genes were present in 65% of strains. It was concluded that there are varied phenotypes and genotypes of Lactobacillus in a Stilton cheese according to site of isolation. Occurrence of different L. plantarum genotypes could contribute to variation in the cheese quality from batch to batch and provides criteria for selecting isolates as potential adjunct cultures. |
format | Online Article Text |
id | pubmed-7236593 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Frontiers Media S.A. |
record_format | MEDLINE/PubMed |
spelling | pubmed-72365932020-05-29 Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation Mugampoza, Diriisa Gkatzionis, Konstantinos Swift, Benjamin M. C. Rees, Catherine E. D. Dodd, Christine E. R. Front Microbiol Microbiology This study has characterized the dominant non-starter Lactobacillus species isolated from different sites in a Stilton cheese to establish its diversity, stress-tolerance, anti-microbial activity and potential contribution to quality of cheese. Fifty-nine Lactobacillus isolates were cultured from the outer crust, blue veins and white core of the cheese and were speciated phenotypically and by 16S rDNA sequence analysis. Lactobacillus plantarum was the dominant species detected with only two isolates identified as Lactobacillus brevis. Strains were typed by pulse-field gel electrophoresis (PFGE) using the enzyme NotI to examine their genomic diversity. Cluster analysis of PFGE patterns produced five major clusters which associated isolates with their sites of isolation within the cheese. One L. plantarum isolate from each cheese site was selected and evaluated for salt, acid, relative humidity, and heat tolerance to determine whether stress conditions within the isolation site selected their phenotype. D(72°C) values were 6, 13, and 17 s for strains from the crust, veins and core, respectively, suggesting strains on the crust may not have been able to survive pasteurization and therefore had been added post-pasteurization. All strains recovered from heat injury within 24–48 h at 4°C. pH values of 3, 3.5, and 4 suppressed growth but strains showed a varying ability to grow at pH 4.5 and 5; isolates from the core (which has the lowest pH) were the most acid-tolerant. All strains grew at 3.5 and 5% salt but were suppressed at 10%; those from the crust (which has a lower water activity) were the most halo-tolerant, growing at 8% salt whereas strains from the core were sensitive to this salt concentration. All 57 L. plantarum isolates were examined for antimicrobial activity and variable activity against Lactobacillus pentosus and other genera was demonstrated; plantaricin EF genes were present in 65% of strains. It was concluded that there are varied phenotypes and genotypes of Lactobacillus in a Stilton cheese according to site of isolation. Occurrence of different L. plantarum genotypes could contribute to variation in the cheese quality from batch to batch and provides criteria for selecting isolates as potential adjunct cultures. Frontiers Media S.A. 2020-05-12 /pmc/articles/PMC7236593/ /pubmed/32477308 http://dx.doi.org/10.3389/fmicb.2020.00904 Text en Copyright © 2020 Mugampoza, Gkatzionis, Swift, Rees and Dodd. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
spellingShingle | Microbiology Mugampoza, Diriisa Gkatzionis, Konstantinos Swift, Benjamin M. C. Rees, Catherine E. D. Dodd, Christine E. R. Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title | Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title_full | Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title_fullStr | Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title_full_unstemmed | Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title_short | Diversity of Lactobacillus Species of Stilton Cheese Relates to Site of Isolation |
title_sort | diversity of lactobacillus species of stilton cheese relates to site of isolation |
topic | Microbiology |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7236593/ https://www.ncbi.nlm.nih.gov/pubmed/32477308 http://dx.doi.org/10.3389/fmicb.2020.00904 |
work_keys_str_mv | AT mugampozadiriisa diversityoflactobacillusspeciesofstiltoncheeserelatestositeofisolation AT gkatzioniskonstantinos diversityoflactobacillusspeciesofstiltoncheeserelatestositeofisolation AT swiftbenjaminmc diversityoflactobacillusspeciesofstiltoncheeserelatestositeofisolation AT reescatherineed diversityoflactobacillusspeciesofstiltoncheeserelatestositeofisolation AT doddchristineer diversityoflactobacillusspeciesofstiltoncheeserelatestositeofisolation |