The Study On The Identification Of The γ-aminobutyric Acid Lactococcus And Fermentation Characteristics

Theγ-aminobutyric acid is widely distributed both in plants and animals and has a lot of Physiological functions for human, such as, theγ-aminobutyric acid can cure Hypertension. So we study the identification of theγ-aminobutyric acid Lactococcus and their fermentation characteristics to benefit the advantages.In this study,we identify the 5 kinds of Lactic acid bacteria IMAU10092,IMAU20032,IMAU10051,IMAU10059 and IMAU20038 by molecular biology means and determinate their fermentation characteristics. The results are as follows:1. We amplify gene sequences of 16S rDNA in 5 kinds of Lactic acid bacteria and analysis 16S rDNA homology of them to build Phylogenetic tree ,the result shows that IMAU10051 and IMAU10059 belong to Lactococcus lactis subsp. Lactis,IMAU10092 and IMAU20038 are defined to Enterococcus durans and IMAU20032 is determined to Pediococcus pentosaceus。2. In the process of fermentation , the hydrolysis ability of protein in Lactococcus increased following the decreasing of PH value and increasing ofTA value。The hydrolysis ability of protein in fermented milk samples which added IMAU10092,IMAU10051 and IMAU10059 is low and slow。3. The value of OD600 and GABA increased,but the dropping of PH value influence the activity of Glutamic acid decarboxylase and the content ofγ-aminobutyric acid。At the end of the fermentation, the content ofγ-aminobutyric acid which added IMAU20032 is the highest,up to 42.21mg/L。...