关键词: 胡萝卜软腐欧文氏菌;苎麻;脱胶;紫外诱变;酶活

Abstract:

In order to obtain high efficient degumming strain for fiber crops, the strain CXJZU-120 was screened by UV mutagenesis treatment of CXJZ95-198 for 120 s. By studying the biological characteristics and function of degumming, the results showed that strain CXJZU-120 with stable characters, could finish ramie degumming within 5.5~6.0 h. The removal rate of non-cellulose materials was 87.22%. The strain had a high activity of pectinase, β-mannanase and xylanase in fermentation liquid after cultivation for 10 h, which reached 211.2 U/mL, 3748 U/mL and 96.6 U/mL, respectively. It showed dark brown after cultivation for 16.0~17.0 h in slant medium, bluish green appeared after cultivation for 5.0~5.5 h in fermentation liquid, and it began to present blue color when inoculating on ramie for 5.0~5.5 h. These results indicated that the ability of degumming and performance of enzyme production of the mutant strain CXJZU-120 were increased compared with the original strain. And because of the characteristics of rapid-reproduction and presentation of special colors in ramie fermentation, the strain CXJZU-120 has important significance in degumming application for fiber crops.

Key words: Erwinia carotovora, ramie, degumming, UV mutagenesis, enzyme activity