摘要
本文对一株乳酸菌所产谷氨酸脱羧酶的酶学性质进行了较系统的研究,其中包括酶的热稳定性、pH稳定性及温度、pH和一些化学物质对酶活的影响。结果表明:此酶的最适温度为52℃,最适pH为4.5,米氏常数Km=24mmol。PLP、VB6及Ca2+在一定程度上都能促进酶活,且在含量小于100μmol时,作用程度为PLP>VB6>Ca2+。乙酸浓度小于0.05mol/L也能提高酶活力。
This article has made a systematic research on the property of glutamate decarboxylase which was produced by a lactic acid bacterium. The heat stability, pH stability as well as the effect of pH, temperature and some chemical substances were studied. The reasult showed that the optimum temperature and pH were 52℃ and 4.5 respectively. The Km value of the enzyme was 24mmol. PLP, VB6 and Ca2+ showed positive effect on the activity of GAD in the following order: PLP>VB6>Ca2+ even when their concentration was under 100μmol. If the concentration of the acetate was under 0.05mmol, the enzyme activity was also enhanced.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2005年第4期100-104,共5页
Food Science
关键词
乳酸菌
谷氨酸脱羧酶
Γ-氨基丁酸
酶学性质
lactic acid bacterium
glutamate decarboxylase(GAD)
γ-amino butyric acid(GABA)
enzyme activity
