Premium
A differential medium for lactic acid‐producing bacteria in a mixed culture
Author(s) -
Lee H.M.,
Lee Y.
Publication year - 2008
Publication title -
letters in applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.698
H-Index - 110
eISSN - 1472-765X
pISSN - 0266-8254
DOI - 10.1111/j.1472-765x.2008.02371.x
Subject(s) - bromocresol purple , bromophenol blue , agar , bromocresol green , food science , bifidobacterium bifidum , microbiology and biotechnology , bacteria , lactobacillus acidophilus , weissella , biology , lactic acid , lactobacillus brevis , fermentation , lactobacillus , chemistry , probiotic , lactobacillus plantarum , bifidobacterium , chromatography , biochemistry , genetics , leuconostoc
Aims: Modified deMan‐Rogosa Sharpe agar containing bromophenol blue (mMRS‐BPB) was tested as a medium for counting and differentiation of each lactic acid‐producing bacterium (LAB), especially in a mixed culture. Methods and Results: Type strains of 10 LAB species ( Lactobacillus acidophilus , L. brevis , L. bulgaricus , L. gasseri , L. paracasei , L. plantarum , L. reuteri , Weissella confusa , Bifidobacterium bifidum and B. infantis ) and five commercial yogurts were inoculated on plate count agar with bromocresol purple, mMRS, and mMRS‐BPB. Each type strain showed more clearly formed colonies on the three media under anaerobic conditions than under aerobic conditions. Especially each type strain produced colonies with specific characteristics of each species on mMRS‐BPB. Commercial yogurts produced the largest number of colonies with various shapes and colours on mMRS‐BPB. Conclusions: Modified deMan‐Rogosa Sharpe agar containing bromophenol blue under anaerobic conditions is appropriate for counting and differentiating each LAB in a mixed culture. Significance and Impact of the Study: Modified deMan‐Rogosa Sharpe agar containing bromophenol blue will be useful in isolation and enumeration of each LAB from fermented foods as well as intestinal microflora.