甲壳素脱乙酰酶产生菌的选育研究

Screening and Breeding of the Microbial Strain for Producing Chitin Deacetylase

为获得甲壳素生物转化法制备壳聚糖的甲壳素脱乙酰酶菌株,利用平板变色圈法,从经过自然富集的土壤中筛选到一株产甲壳素脱乙酰酶的霉菌CR-3,产酶活力达到41.6 U/m L。通过形态学特征和18S r DNA序列分析,确定其为杂色曲霉(Aspergillus versicolor)。经过紫外诱变后,筛选到产酶活力提高的突变株SD-3,酶活力提高到78.3 U/m L。进一步对突变株的产酶培养基组成进行了优化,产酶活力提高到147.4 U/m L。研究的结果有良好的实际应用价值。

In order to obtain a microbial strain for producing chitin deacetylase, which can be applied in bioconversion of chitin to chitosan,a strain designated with CR-3 that could produce chitin deacetylase with the activity of41. 6 U / m L was screened out from the soil after cultural enrichment with crab. By morphology characteristics and 18 S r DNA sequencing analysis,the strain CR-3 was identified as an Aspergillus versicolor. Afterwards,the strain CR-3 was irradiated by ultraviolet,and a mutant strain SD-3 was selected,which could produce chitin deacetylase with the activity of 78. 3 U / m L. After optimization of the culture medium composition,the activity of chitin deacetylase was increased to147. 4 U / m L. The results showed some industrial application value.