摘要
采用合成底物对毛霉和白腐乳发酵中分离出的细菌JS3及酵母JSBB2的肽酶活力进行了检测,测定表明微生物具有明显的二肽酶和羧肽酶活力,其中毛霉的氨肽酶和内肽酶活力较高,细菌表现出明显的氨肽酶活力,而Alcalase的外切酶活力不足。两步法水解实验表明,毛霉和细菌的粗酶液有利于降低Alcalase水解大豆蛋白(SPI)后溶液的苦味,经毛霉粗酶液作用后大豆蛋白水解液的水解度提高了16.2%,而酵母发酵液的水解和脱苦作用均不明显。
Mucor, Bacteria JS3 and Yeast JSBB2, previously isolated from a White Sufu, were tested for their peptidase activities. Dipeptidase and carboxypeptidase were showed prominent in the microorganisms, distinct aminopeptidase and endopeptidase activities were detected in Mucor, obvious aminopeptidase activities were showed in Bacteria JS3, but Alcalase exhibited poor aminopeptidase activities. Soybean protein isolate （SPI） （5% w/w） hydrolyzed by Alcalase were incubated by the crude enzymes of Mucor and isolated strains, the degree of hydrolysis （DH） of Mucor enzymatic reaction increased 16.2%, but DH of Bacteria JS3 and Yeast JSBB2 raised little. The two-step hydrolysing experiment proved that peptidase of Mucor and bacteria are valuable to reduce the bitter peptides of soybean proteins.
出处
《陕西科技大学学报（自然科学版）》
2006年第3期31-36,共6页
Journal of Shaanxi University of Science & Technology
基金
广东省科技攻关项目(2003C20408)
关键词
肽酶
苦味值
大豆蛋白
白腐乳
peptidase
bitterness
soybean protein
White Sufu
