Screening,Mutation Breeding and Straw Degradation Effects of High-Yield Cellulase Strains
The aim of this study was to breed high-yield cellulose degrading bacteria to improve the efficiency of cellulose degradation.Cellulose degrading bacteria were screened from rumen fluid of beef cattle by Congo-Red staining method,and then high cellulose degrading bacteria were screened after(atmospheric room tem-perature plasma)ARTP mutagenesis,and the degradation effects of straw were studied.The results show as follows:1)the initial cellulose-degrading strain C8 was screened from rumen fluid of beef cattle.The holoen-zyme(FPA),exoglucanase(C1),endoglucanase(CMC)and β-glucosidase(β-Gase)activities of strain C8 were 3.96,1.08,2.21 and 0.51 U/mL,respectively,and the dry matter degradation rate of straw was 35.79％.It was biologically identified as Bacillus subtilis and named Bacillus subtilis C8.2)Using Bacillus subtilis C8 as the initial strain,the mutant strain AC83 was selected by ARTP mutagenesis,and its FPA,C,,CMC and β-Gase activities were 6.31,1.18,3.63 and 1.05 U/mL,respectively.Compared with the original strain,they increased by 59.34％,9.26％,64.25％and 105.88％,respectively.The dry matter degradation rate of straw was 43.64％,which was 21.93％higher than that of the initial strain.3)The mutant strain AC83 had good genetic stability after 6 successive generations of culture.In this study,the mutant strain AC83 is screened to have strong cellulose degradation ability,which provides more possibilities for improving feed con-version rate.[Chinese Journal of Animal Nutrition,2024,36(12):8126-8136]
万方数据
维普
