Lactic acid bacteria’s Isolation and its Optimization of GABA Fermentation Condition
Abstract:In this paper,we separated a lactic acid strain from commercial yogurt which can producing GABA.we initially identified it as L.delbrueckii through Ecology identification、Physiological and Biochemical identification。Exploring determination of GABA levels,we found that 2% concentration of phenol, 2.08% sodium hypochlorite concentration have benefit to Colorimetry。Although this method is suitable for large sample testing,it is susceptible to the impact of free ammonia in solution。Exploring determination of GABA levels,we found that the developing solvent’s(butanol: acetic acid: water) volume ratio of 4:1:3, the color temperature and time were 80℃, 30min, determining at 510nm have benefit to Chromatography—Elution。After three single-factor test s--pH, temperature 、inoculation and Orthogonal optimization,we found at pH6.5,、temperature 30 ℃、inoculum 7% ,the GABA production was 0.177 g / L。The experiment can be used as initial exploration of brown rice biotransformation of GABA.
Keywords:γ-aminobutyric acid; L.delbrueckii; Brown rice;GABA examination