Construction of Actinomycetes complex flora in degrading corn straw and its degradation effect evaluation

Abstract As a kind of agricultural waste, corn straw internal lignocellulose content is higher, but it is difficult to be used efficiently because of its difficult degradation. In this experiment, three cellulose-degrading actinomycetes were constructed as complex flora, then the cellulose degradation conditions and degradation activity were optimized and evaluated. The results showed that when the complex flora was inoculated into the fermentation medium with pH of 7, volume fraction of 3%, and the degradation rate of corn straw could reach 38.24% after 5 d of fermentation at 28°C and 180 rpm. Cellulose, hemicellulose and lignin in corn straw were degraded by 33.97%, 34.08%, and 21.52%, respectively. The results of scanning electron microscopy showed that the waxy layer on the surface of corn straw was thinned and gradually disappeared by the fermentation of complex flora. Fourier transform infrared spectroscopy results showed that the complex flora could change the internal functional groups of corn straw in different fermentation periods. The detected compounds in fermentation system indicated that corn straw were efficiently degraded. According to the above results, the constructed complex flora had a higher ability to degrade corn straw, and provided research ideas for the development and utilization of biomass resources.