Kluyveromyces fragilis β-D-半乳糖苷酶催化合成低聚半乳糖  

Factors affecting galacto-oligosaccharide synthesis by k.fragilis β-D-galactosidase

作　　者：李素芬[1] 刘建福[2] 陈占洲[1] 

机构地区：[1]河北工程大学农学院,邯郸056001 [2]天津商学院生物技术与食品科学学院,天津300134

出　　处：《食品科技》2007年第7期174-177,共4页Food Science and Technology

摘　　要：低聚半乳糖具有促进肠道有益菌增殖、抗龋齿、低能量等特定的生理功能。研究了酶反应条件对脆壁克鲁维酵母(kluyveromyces fragilis)β-D-半乳糖苷酶催化合成低聚半乳糖的影响。以乳糖为底物,k.fragilis β-D-半乳糖苷酶催化合成低聚半乳糖的最适温度为40℃,最适pH值为7.0,反应20h低聚半乳糖的产率达到最大。底物初始浓度影响k.fragilis β-D-半乳糖苷酶催化合成低聚半乳糖的产率,乳糖起始浓度由110mg/mL增加到660mg/mL,低聚半乳糖的含量从43mg/mL增加到207mg/mL。Galacto-oligosaccharide（GOS） was nondigestible saccharide with the physiological properties of biofido growth, non-cavity, low calor. The aim of this research was to quantify the effect of temperature, pHvalue, substrate concentration and reaction time on galacto-oligosaccharide（GOS） yield. The optimal temperature and pH value for GOS production by k. fragilis β-D-galactosidase was 40℃and 7.0, respectively. The higher GOS yield was found at higher substrate concentration. Enzymatic reaction speed was faster at the beginning of reaction, then decreased, and chemical balance was reached after 20h incubation at 40℃, 207mg/ mL GOS was produced with 660mg/mL lactose as substrate at optimal reaction conditions.

关 键 词：KLUYVEROMYCES fragilis B—D一半乳糖苷酶 酶法合成 低聚半乳糖 

分 类 号：TQ929.2[轻工技术与工程—发酵工程]