Screening and identification of efficient lignin-degrading strain in rape straw and their degradation applications
The experiment aimed to study the screening,identification,and degradation efficiency of efficient lignin-degrading strain in rape straw.A highly efficient lignin degrading strain MS25 was screened from the returned soil of rapeseed straw and identified as a Penicillium fungus.Based on single factor experiments and response surface methodology,the enzyme production characteristics was invstigated and the conditions of MS25 strain was optimized,and the lignin degradation ability was tested.The results showed that the optimal time for the strain to produce laccase(Lac)was 5 days,and the time to produce peroxidase(Lip)and manganese peroxidase(MnP)was 7 days.The best temperature was 50 ℃,the shaking table speed was 140 r/min,the carbon to nitrogen ratio was 15,and the most suitable pH value for producing MnP was 5,while the most suitable pH values for producing Lip and Lac were 6.The optimal enzyme production conditions after optimization were temperature of 50.22 ℃,carbon to nitrogen ratio of 12.29,and pH value of 6.21.Under these conditions,the activities of Lip,MnP,and Lac enzymes were 1 984.89,774.87,and 291.74 U/L,respectively,which were 33.97％,33.28％,and 40.35％higher than before optimization.Under optimal conditions,the lignin degradation rates of straw and fungal bran of the strains were 44.67％and 43.29％,respectively.The study indicates that strain MS25 can effectively degrade lignin and can be used as a high-quality microorganism for rape straw fermentation,and can be specifically applied in the field of feed production.
万方数据
维普
