Optimization of the Production of ε-Poly-L-Lysine by Novel Producer Lactic Acid Bacteria Isolated from Traditional Dairy Products

New strains of lactic acid bacteria (LAB) were isolated from different traditional dairy products. Six new strains named Lactobacillus delbrueckii strain A01, Lactobacillus delbrueckii subsp. bulgaricus strain D01, Lactobacillus delbrueckii subsp. bulgaricus strain E01, Lactococcus lactis strain G01, Lactobacillus delbrueckii strain C01, and Lactobacillus delbrueckii subsp. bulgaricus strain F01 were identified using 16S rDNA sequencing, morphological and biochemical traits. All strains have been registered in the National Center for Biotechnology Information (NCBI) with accession numbers MN611241.1, MN611300.1, MN611301.1, MN611303.1, MN611241.1, and MN611299.1, respectively. Having found ε-Poly-L-Lysine (ε-PL) in all strains isolated, Lactobacillus delbrueckii strain A01 was identified as an active producer of ε-Poly-L-Lysine (ε-PL). The one-factor-at-a-time method and central composite design were applied to optimize ε-Poly-L-Lysine (ε-PL). A predicted 200 ppm of ε-PL was obtained in the medium containing the lowest level of glucose, 25 g/l, and yeast extract, 6 g/l.

Download Full-text

Exopolysaccharides Produced by Lactic Acid Bacteria of Kefir Grains

Zeitschrift für Naturforschung C ◽

10.1515/znc-2002-9-1009 ◽

2002 ◽

Vol 57 (9-10) ◽

pp. 805-810 ◽

Cited By ~ 27

Author(s):

Ginka I. Frengova ◽

Emilina D. Simova ◽

Dora M. Beshkova ◽

Zhelyasko I. Simov

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Streptococcus Thermophilus ◽

Lactobacillus Helveticus ◽

Lactobacillus Delbrueckii ◽

Monomer Composition ◽

Kefir Grains ◽

The One ◽

Lactobacillus Delbrueckii Subsp

A Lactobacillus delbrueckii subsp. bulgaricus HP1 strain with high exopolysaccharide activity was selected from among 40 strains of lactic acid bacteria, isolated from kefir grains. By associating the Lactobacillus delbrueckii subsp. bulgaricus HP1 strain with Streptococcus thermophilus T15, Lactococcus lactis subsp. lactis C15, Lactobacillus helveticus MP12. and Sacharomyces cerevisiae A13, a kefir starter was formed. The associated cultivation of the lactobacteria and yeast had a positive effect on the exopolysaccharide activity of Lactobacillus delbrueckii subsp. bulgaricus HP1. The maximum exopolysaccharide concentration of the starter culture exceeded the one by the Lactobacillus delbrueckii subsp. bulgaricus HP1 monoculture by approximately 1.7 times, and the time needed to reach the maximum concentration (824.3 mg exopolysacharides/l) was shortened by 6 h. The monomer composition of the exopolysaccharides from the kefir starter culture was represented by glucose and galactose in a 1.0:0.94 ratio, which proves that the polymer synthesized is kefiran.

Download Full-text

Transposition in Lactobacillus delbrueckii subsp. bulgaricus: identification of two thermosensitive replicons and two functional insertion sequences

Microbiology ◽

10.1099/mic.0.25827-0 ◽

2003 ◽

Vol 149 (6) ◽

pp. 1503-1511 ◽

Cited By ~ 9

Author(s):

Pascale Serror ◽

Golnar Ilami ◽

Hichem Chouayekh ◽

S. Dusko Ehrlich ◽

Emmanuelle Maguin

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactobacillus Delbrueckii ◽

Lactobacillus Bulgaricus ◽

Insertion Sequences ◽

Rolling Circle ◽

Delivery Vector ◽

Lactobacillus Delbrueckii Subsp

In this report, it is shown that the rolling circle replicon pG+host and the theta replicon pIP501 are thermosensitive in Lactobacillus delbrueckii subsp. bulgaricus (Lactobacillus bulgaricus). Using a pIP501 derivative as a delivery vector for six insertion sequences originating from lactic acid bacteria, it is shown that IS1223 and IS1201 transpose in L. bulgaricus.

Download Full-text

Antibiotic susceptibility of different lactic acid bacteria strains

Beneficial Microbes ◽

10.3920/bm2011.0016 ◽

2011 ◽

Vol 2 (4) ◽

pp. 335-339 ◽

Cited By ~ 20

Author(s):

N. Karapetkov ◽

R. Georgieva ◽

N. Rumyan ◽

E. Karaivanova

Keyword(s):

Cell Wall ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactobacillus Acidophilus ◽

Streptococcus Thermophilus ◽

Lactobacillus Helveticus ◽

Lactobacillus Delbrueckii ◽

Cell Wall Synthesis ◽

High Susceptibility ◽

Lactobacillus Delbrueckii Subsp

Five lactic acid bacteria (LAB) strains belonging to species Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis and Streptococcus thermophilus were tested for their susceptibility to 27 antibiotics. The minimum inhibitory concentrations of each antimicrobial were determined using a microdilution test. Among the strains a high susceptibility was detected for most of the cell-wall synthesis inhibitors (penicillins, cefoxitin and vancomycin) and resistance toward inhibitors of DNA synthesis (trimethoprim/sulfonamides and fluoroquinolones). Generally, the Lactobacillus strains were inhibited by antibiotics such as chloramphenicol, erythromycin and tetracycline at breakpoint levels lower or equal to the levels defined by the European Food Safety Authority. Despite the very similar profile of S. thermophilus LC201 to lactobacilli, the detection of resistance toward erythromycin necessitates the performance of additional tests in order to prove the absence of transferable resistance genes.

Download Full-text

Production of natural folates by lactic acid bacteria starter cultures isolated from artisanal Argentinean yogurts

Canadian Journal of Microbiology ◽

10.1139/w2012-026 ◽

2012 ◽

Vol 58 (5) ◽

pp. 581-588 ◽

Cited By ~ 60

Author(s):

Jonathan Emiliano Laiño ◽

Jean Guy LeBlanc ◽

Graciela Savoy de Giori

Keyword(s):

Lactic Acid ◽

Folic Acid ◽

Lactic Acid Bacteria ◽

Culture Medium ◽

Streptococcus Thermophilus ◽

Starter Cultures ◽

Lactobacillus Delbrueckii ◽

Nonfat Milk ◽

Native Strains ◽

Lactobacillus Delbrueckii Subsp

Folate is a B-group vitamin that cannot be synthesized by humans and must be obtained exogenously. Although some species of lactic acid bacteria (LAB) can produce folates, little is known about the production of this vitamin by yogurt starter cultures. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains were isolated from artisanal Argentinean yogurts and were grown in folate-free culture medium (FACM) and nonfat milk after which intracellular and extracellular folate production were evaluated. From the initial 92 isolated LAB strains, 4 L. delbrueckii subsp. bulgaricus and 32 S. thermophilus were able to grow in the absence of folate. Lactobacillus delbrueckii subsp. bulgaricus CRL 863 and S. thermophilus CRL 415 and CRL 803 produced the highest extracellular folate levels (from 22.3 to 135 µg/L) in FACM. In nonfat milk, these strains were able to increase the initial folate concentrations by almost 190%. This is the first report where native strains of L. delbrueckii subsp. bulgaricus were shown to produce natural folate. The LAB strains identified in this study could be used in developing novel fermented products bio-enriched in natural folates that could in turn be used as an alternative to fortification with the controversial synthetic chemical folic acid.

Download Full-text

Determination of bacteriocin-encoding genes of lactic acid bacteria isolated from traditional dairy products of Luxor province, Egypt

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-020-00031-3 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Rasha Mohamed Refay ◽

Hala Mohamed Abushady ◽

Sara Adel Amer ◽

Mahmoud Ahmed Mailam

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Dairy Products ◽

Traditional Dairy Products ◽

Encoding Genes

Download Full-text

Compositional characteristics of commercial yoghurt based on quantitative determination of viable lactic acid bacteria

Acta periodica technologica ◽

10.2298/apt0940087p ◽

2009 ◽

pp. 87-94

Author(s):

Dragana Pesic-Mikulec ◽

Gordana Niketic

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Quantitative Determination ◽

Dairy Products ◽

Consumer Preferences ◽

Streptococcus Thermophilus ◽

Lactobacillus Delbrueckii ◽

Manufacturing Methods ◽

The Many

Yoghurt quality is particularly difficult to standardize because of the many forms, varieties, manufacturing methods, ingredients and consumer preferences that exist. Since these factors will always play an important role, it is unlikely that a uniform yoghurt quality concept will ever emerge, such as has been developed for other dairy products. There are a number of common denominators, however that have bearing on yoghurt quality. Since a number of producers are recognized within the broad category entitled yoghurt. This situation makes yoghurt an interesting, challenging, but also a confusing area to work in. The present investigation was undertaken to isolate from commercial yoghurt the strains involved in its manufacture and determine the characteristics of Streptococcus thermophilus and Lactobacillus delbrueckii subsp.bulgaricus. This study is concerned with the lactic acid bacteria (L.delbrueckii subsp. bulgaricus and S. thermophilus) growth in yoghurt from involving different procedures and with the determination of the number of lactic acid bacteria in dependence of the temperature and acidity in the period of storage. Predominant samples of yoghurt were with 11-107/ml lactic acid lactococci (44.28%).

Download Full-text

Diversity of Lactic Acid Bacteria in dairy products of Southern Rajasthan

South Asian Journal of Experimental Biology ◽

10.38150/sajeb.3(2).p92-96 ◽

2013 ◽

Vol 3 (2) ◽

pp. 92-96

Author(s):

Nadim Chishty ◽

Srinivasan R ◽

Dinesh K. Kumawat ◽

Yogesh Franklin ◽

Anil Tripathi

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

16S Rdna ◽

Dairy Products ◽

Raw Milk ◽

16S Rdna Gene ◽

Growth Requirements ◽

Rdna Sequencing ◽

Fermented Dairy Products ◽

Fermented Dairy

Lactic acid bacteria (LAB) are a group of gram positive, non spore forming, cocci or rod shaped, catalase negative and fastidious organisms. They are considered as “GRAS” (Generally Recognized As Safe) organisms. A total of 86 bacterial isolates were isolated from different samples of raw milk, buttermilk and curd by using MRS agar and M17 agar. Lactic Acid Bacteria have similar nutritional and growth requirements, it becomes difficult and laborious to identify them by classical methods. Hence, molecular typing was attempted to find the diversity, 16S rDNA gene amplification was done using specific 16S rDNA primers and amplified gene products were digested with different restriction endonuclease enzymes. Further the 16S rDNA sequencing was carried out and the sequences were compared with the available gene sequences in NCBI website by using BLASTn. All isolates obtained from dairy products were accurately identified as Lc. lactis, Lb. plantarum, Leu. mesenteroides, E. durans, Lb. fermentum, Lc. garviae and Lb. casei. The predominant LAB were Lactobacillus casei and Leu. mesenteroides, which were isolated from all sampling sites. The results demonstrate that traditional fermented dairy products from different regions of Rajasthan have complex compositions of LAB species.

Download Full-text