[Screening of two straw-cellulose degrading actinomycetes].

The aim of this study was to screen microorganisms that could degrade rice straw. We used selective medium to screen strains and determined straw fracture tension strength, weight loss, lignocellulose decomposition rate and extracellular enzyme activity as re-screening methods after 10 days shake flask culture. We isolated two antinomycetes (A3 and A6), the highest cellulose enzyme activity of holoenzyme, beta3-Glucosidase, endonuclease and exonclease for A3 were 12.84, 6.23, 24.56 and 14.00 U/mL, and for A6 12.85, 6.53, 17.80 and 18.80 U/mL. The hemicelluloses enzyme activity was 83.05 for A3 and 52.98 U/mL for A6. Both strains belonged to Streptomyces. With 10 days' treatment, inoculated straws showed a decrease of straw fracture tension strength by 62.67% (A3) and 66.67% (A6), while weight loss of straw was 31.50% (A3) and 35.83% (A6). A3's decomposition rate of cellulose, hemicellulose and lignin was 38.73% , 33.16% and 20.68% , and 47.69% , 28.64% and 22.59% for A6. Antinomycetes A3 and A6 could degrad cellulose, hemicellulose and lignin.