The Filtration And Mutagenesisof White-rot Fungi And Study On The Degrade Ability Of Stalk

In order to investigate the stalk-degrading effects of white-rot fungi,the test first filtrated five preponderant strains from the soil,which is H1,H2,H3,H5,H8, and then make use of ⁶⁰Co-γrays to radiant exposure the original strains under radiation dose of 1200Gy,test obtained the corresponding mutagenesis strains by repeatedly filtration to study three kinds of the lignin-degrading enzyme activity (Lignin peroxidase,Manganese-dependent peroxidase, Laccase) and growth quantity of original strains and mutagenesis strains, and wheat stalk inoculated by the test strains after culturing for 10 days, 20 days, 30 days ,the change of whose each component (crude protein, neutral detergent fiber, acid detergent fiber, acid detergent lignin) was also observed. Analysised the results of Lignin peroxidase enzyme activity and found that the enzyme activity of mutagenesis strains of h8 produced up to 197.62U / L, wich is much higher than any other strains, and it is 1.95 times of the original strains; analysised the results of Manganese-dependent peroxidase enzyme activity and found that the enzyme activity of mutagenesis strains of h5 culturing for 8 days arrived at the peak,which enzyme activity is 367.38 U / L,and it is 1.44 times of the original strains, while the biggest difference between original strains and mutagenesis strains are strains of H3 and h3, the highest enzyme activity of mutagenesis strains of h3 is 277.95 U / L,which is 1.93 times of the original strains; analysised the results of laccase enzyme activity and found that the enzyme activity of mutagenesis strains of h3 produced up to 883.06 U / L, it is 1.51 times of the original strains,the laccase enzyme activity of mutagenesis strains of h2 produced up to 653.61 U / L, which is 2.10 times of the original strains whose enzyme activity is 311.67 U / L;the growth quantity of strains after mutagenesis significantly increased as compared with the original strains;the acid detergent lignin content of stalk medium decreased significantly after culturing for 30 days, thereinto the acid detergent lignin degradation rate of mutagenesis strains of h3 is highest, arriving at 50.46%,it is 1.88 times of the original strains of H3,while the greatest difference between original strains and mutagenesis strains are strains of H2 and h2, aberrant strain,the acid detergent lignin degradation rate of mutagenesis strains is 2.23 times of the original strain. To sum up, white-rot fungus had a strong role in the lignin-degrading of stalk, while taking advantage of ⁶⁰Co-γray radiation mutagenesis techniques can effectively improve the enzyme activity and lignin-degrading ability of strains.