摘要
以脱脂玉米胚为原料,利用其中的蛋白酶和谷氨酸脱羧酶(GAD)富集γ-氨基丁酸。通过实验确定的富集工艺条件为:脱脂玉米胚与磷酸盐溶液(0.06mol/L、pH5.7)比例1∶40(g∶mL),反应时间5h,温度40℃,pH值5.7;同时添加600μmol/LCa2+可将GABA产量提高到4mg/g,比未富集时提高了10倍。另外,通过添加底物L-谷氨酸进行反应,脱脂玉米胚与磷酸盐缓冲液(0.08mol/L、pH5.7)比例为1∶40(g∶mL),VB6和CaCl2的添加量分别为3mmol/mol(Glu)和15mmol/mol(Glu),脱脂玉米胚与L-Glu质量之比为45∶1,40℃下反应6h,Glu的转化率可达100%,GABA产量为15mg/g,比未富集时提高40倍。
The γ-GABA accumulation of the degreased corn germ was studied by the protease and the glutamate decarboxylase （ab. GAD） which were the endoenzyme of corn germ. According to the experiments, the optimum conditions of GABA-accumulation were determined as follow： degreased corn germ--phosphate buffer（0.06 mol/L, pH 5.7） ratio 1 ： 40（W/V）, reaction time 5 h, temperature 40℃ and pH 5.7 ; while 600 μmol/L Ca^2 ＋ was added, the yield of GABA reached to 4 mg/g which was10 times than before. In addition, the reaction condition of L-glutamic acid as the substrate also was studied： degreased corn germ-phosphate buffer （0.08 mol/L, pH5.7） ratio 1 ： 40 （W/V） , 3 mmol/（mol Glu） V B6 and 15 mmol/mol （Glu） Ca^2＋ were added, reaction time 6 h, temperature 40℃, when degreased corn germ-L-Glu ratio was 45：1 （W/W）, the conversion rate of L-GIu reached 100%, with the yield of GABA 15 mg/g which was 40 times than before.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2009年第4期87-91,共5页
Food and Fermentation Industries
作者简介
硕士研究生
李楠为通讯作者。
