摘要
从土壤中筛选出1株产外切型异麦芽三糖水解酶的黄绿青霉,可特异性地水解右旋糖酐只产生异麦芽三糖。该菌株产酶最优条件为:培养液中淀粉、葡聚糖、NH4Cl、酵母膏的质量分数分别为1%、1%、0.1%、0.1%,pH 6.0,接种量1%,装液量50 mL/250 mL,转速120 r/min。25℃培养13 d酶活达到176.80 U/mL。酶的最适作用温度为55℃,在50℃半衰期为3 h,最适作用pH为6.5,在pH 4.0～pH 6.5范围内稳定;金属离子K+、Ba2+显著促进酶活,Ca2+、Fe2+强烈抑制酶活;150 mmol/L NaCl所产生的离子强度促进酶活。
A strain of Penicillium citreoviride was screened from soil to produce exo-isomaltotriodextranase, which specifically released isomaltotriose as main products from dextran T70. The optimum condition for Isomaltotriodextranase production consisted of 1% starch, 1% dextran, 0. 1% NH4Cl and 0.1% yeast extract, the initial pH for 6.0, 1% inoculating quantity, rate of shaking flask with 50 mL liquid in a 250 mL flask was 120 r/min. After fermentation for 13 days at 25℃ , the enzyme activity was 176.80 U/mL. The enzyme displayed maximum activity at 55℃. The half-life of the enzyme was 3 h at 50℃. The optimum pH was pH 6.5, and the enzyme activity was stable from pH4.0 - 6.5. The enzyme was enhanced by K^＋ and Ba^2 ＋ , but was inhibited by Ca^2＋ , Fe^2＋ . The enzyme activity could be improved by the ionic strength of NaCl at 150 mmol/L.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2010年第7期49-53,共5页
Food and Fermentation Industries
基金
安徽大学211工程学术创新团队资助项目(02203109)
