Production Of Content ?-Aminobutyric Acid (GABA) By Germinated Rice And Lactobacillus Plantarum Fermentation

Gamma aminobutyric acid as in recent years to study hot, has been widely used in the fields of food and feed. Direct Vat Set (DVS) starter improves the fermentation industry labor productivity and product quality. The test aims to strains with a strain of high gamma aminobutyric acid, by the culture medium, culture conditions optimization for high concentration cell culture, and collected cell vacuum freeze drying preparation of lyophilized powder bacteria, to freeze dry bacterium powder as DVS starter application in the germinated brown rice saccharification liquid of gamma amino butyric acid fermentation.For screening through the laboratory preserved strains were screened to strains with high yield of gamma aminobutyric acid, genetic stability after 10 generations, the highest yield was 10.15g/L. Through the single factor experiment, by using orthogonal auxiliary design, find out the culture medium composition and content of gamma aminobutyric acid yield effect of the most significant factors, the optimized TYG medium is the optimum combination:25.00g/L of casein peptone and glucose 10.00g/L yeast extract powder 20.00g/L,2.50g/L sodium succinate, sodium glutamate 25.00g/L. then response surface design to determine the optimal fermentation conditions of inoculation was 3.00%, culture time was 72h, the initial pH value is 6. At this time the product gamma aminobutyric acid yield was the highest,24.58g/L.In order to determine the combination of Lactobacillus plantarum best freeze-drying protective agent, on the basis of single factor experiment, by orthogonal design tests were conducted to obtain the best protection agent:skim milk powder to add 25.00g/L, sucrose 25.00g/L, maltodextrin add 15.00g/L, then bacterial mud and protection agent between the ratio of 1:5. Under the condition of Lactobacillus plantarum survival rate can reach 68.90%. The number of live bacteria is 5.80 * 1010cfu/mLThe experiment of brown rice germination condition and saccharification conditions were studied to determine the optimal conditions for germination:soaking time was 12h, soaking temperature of 25?, germination time 32.00h,0.30mol/L phosphate buffer solution,0.30mol/L CaCl2 and L-Glu20.00g/L. The germinated brown rice germination rate is highest, the product of gamma aminobutyric acid content is the highest, reaching 35.67mg/100g. On the basis of single factor experiment, to gamma aminobutyric acid (GABA) as the index, of saccharification conditions were optimized through the orthogonal experiment, optimal saccharification conditions:inoculation amount was 0.10%, saccharification temperature of 50?, saccharification time 6h and water ratio of 1:3. At this time of germination than the highest germination rate, germinating of brown rice saccharification product gamma aminobutyric acid (GABA) the highest, reaching 7.68g/L. The optimal fermentation conditions were determined as below 37 ? fermentation temperature, fermentation time 60 h and inoculation quantity was 0.10%. After fermentation product gamma-aminobutyric acid content is the highest,10.12 g/L.