高温碱性果胶酶产生菌的筛选及部分酶学特性研究

Isolation of alkaline pectinase-producing strainand its enzymatic properties

从高温堆肥中分离到一株高产碱性果胶酶的菌株DG-3,经形态、生理生化及16SrDNA序列分析将其鉴定为Bacillus licheniformis DG-3,对DG-3菌株所产碱性果胶酶的初步研究表明,该酶适宜温度范围60～70℃,适宜pH为9.8～10.5。温度稳定性实验表明,碱性果胶酶具有较高的耐热性;6mmol/L的Ca2+对碱性果胶酶具有显著的激活作用。在最适作用条件下,发酵液中碱性果胶酶的酶活达42U/mL,在国内尚未见报道。

A bacterial strain producing high-yield alkaline pectinase was obtained from the high-temperature co-compositing sample.The strain DG-3 was identified as Bacillus licheniformis, based on the morphological, physiological characteristics and ]6S rDNA sequence.The characteristic and the enzyme activity conditions of the alkaline pectinase were studied.As for alkaline pectinase produced by Bacillus licheniformis DG-3, the suitable temperature ranged from 60-70℃,and the suitable pH ranged from 9.8-10.5.The temperature experimentation of stability showed that the enzyme had high heat stability. Fermentation experiment showed that the alkaline pectinase activity was 42U/mL when enzyme was promoted by 6mmol/L Ca^2 ＋ ions.This was one of the best strains reported in literatures at present.