红曲米高产GABA工艺优化和双红曲霉菌联合发酵抑制膳食相关酶活条件优化

Optimization of High Yield of GABA in Red Yeast Rice and Inhibition of Diet-related Enzyme Activity of Co-fermentation Conditions of Two Monascus

以高产γ-氨基丁酸(γ-aminobutyric acid,GABA)菌株MA-25和产降脂色素菌株MP-19为研究菌株,通过单因素、Plackett-Burman实验设计、Box-Behnken响应面实验筛选提高MA-25的GABA产量的红曲米培养条件,并筛选MP-19的色素对α-淀粉酶有最佳抑制效应的氨基酸,然后综合考虑代谢产物GABA产量、α-淀粉酶,蛋白酶和脂肪酶的最佳抑制率,设计正交实验分别选出四组MA-25和MP-19双菌联合发酵的最佳组合,最后考虑降脂能力的最大化。结果表明,优化培养条件是谷氨酸1.18%,葡萄糖+麦芽糖是1.16%,pH为6.08,MA-25红曲米的GABA最高得率5.608 mg·g-1,比优化前(4.651 mg·g-1)提高了20.58%,MP-19最佳降脂氨基酸为L-色氨酸(L-Trp)。双菌联合发酵最佳组合为:粳米20.0%,初始pH为6.5,硫酸铵1.0%,葡萄糖+麦芽糖为0.50%,谷氨酸为1.50%,L-Trp为1.0%,NaH2PO4 1.0%,水57.0%,GABA产量为5.400 mg·g-1,α-淀粉酶抑制率为57.15%,蛋白酶抑制率为28.14%,脂肪酶抑制率为29.67%。

The Monascus anka MA-25 with high yield of γ-aminobutyric acid(GABA)and the Monascus. purpureus MP-19 producing lipid-reduction pigment were selected as the research strains. The best culture conditions of red yeast rice to increase the GABA yield of MA-25 were screened through single factor,Plackett-Burman experimental design and Box-Behnken response surface experimental design. Simultaneously,the amino acid with the best inhibitory effect on α-amylase were screened out for MP-19. Finally,the best culture condition of combined fermentation of MA-25 and MP-19 was selected by orthogonal experiment to achieve the goal that the metabolites not only high GABA production but also the best inhibition rate of dietary related enzymes. The results showed that the optimized culture conditions of MA-25 were glutamate 1.18%,glucose maltose 1.16% and pH6.08% and the highest yield of GABA in red yeast rice of MA-25 was 5.608 mg·g-1,which was 20.58% higher than that before optimization(4.651 mg·g-1). Besides,the optimumα-amylase-reduction amino acid of MP-19 was L-tryptophan(L-Trp). Finally,considering the maximization of lipid reduction ability,the optimum condition of co-fermentation of MA-25 and MP-19 was that:Rice 20%,ammonium sulfate 1.0%,initial pH6.5,glucose maltose 0.50%,glutamic acid 1.50%. L-Trp 1.0%,NaH2PO4 1.0%,water 57.0%,and the GABA production was 5.400 mg ·g-1,α-amylase inhibition rate was 57.15%,protease inhibition rate was 28.14%,lipase inhibition rate was 29.67%.