| Chinese herbal medicine industry is a traditional industry in China. Accompanied by the production of Chinese herbal medicine, a considerable amount of dregs of Chinese herbal medicine were discharged.The annual output of dregs of Chinese herbal medicine is 3,000 tons. Besides crude fiber, the dregs of Chinese herbal medicine contain a large amount of reusable substances (e.g. active components, crude proteins, crude fats, mineral nutrients) In this study, I will screen microbial strains which can destroy plant cell wall efficiently so as to reuse Astragalus dregs. These microbial strains are collected from in Zhejiang province. Through fermenting dregs of Chinese herbal medicine with these strains, more effective ingredients and nutrient will be released. Eventually, we would produce a new feed additive from herbal dregs, and develop a new method for green farming industry. Specific experiments include:First screening 160 microbial strains were isolated which could grow in the carboxymethyl cellulose (CMC) medium from the rotten straw, whithered leaves, soil and the dung samples. So these strains could grow when CMC-Na was the carbon source. These strains were incubated in Congo red and cellulose screening liquid medium and screened again,to get strains which could degrade cellulose. Eventually,we obtained 8 species of bacteria and 2 species of fungi.Second screening Based on strains screened above,the content of the Astragaloside IV (the AST) was examined in the fermentation liquor, to screen strains which can destroy plant cell wall completely.Results showed that the fungi L-6, the bacterium No.5 and the bacterium No.6 were the best strains.And their degradation rates of cellulose are highest, and are 3.95±0.123.61±0.23 and 3.28±0.33 respectively.So the fungi L-6, the bacterium No.5 and the bacterium No.6 were the best strains for further investigation.Late screening The Astragalus dregs was fermented with the fungi L-6, the bacteria No.5 and the bacteria No.6 resepctively. All of them have good cellulose degradation and plant cell wall rupture ability. Then, activities of enzymes in the fermentation liquor were examined fter 24 h,36 h,48 h,60 h and 72 h incubation. These enzymes include carboxymethyl cellulose enzymes(CMCase), FPase, Xylanase and Pectase. The results showed that the enzyme activity of the fungi L-6 was higher than the bacteria No.5 and the bacteria No.6. So the fungi L-6 is the most appropriate for fermentation of dregs of Chinese herbs.The preliminary study of fermentation conditions Using FPase and Xylanase as testing index, optimal carbon source, nitrogen source and growth temperature were screened through the'single factor'method,and mineral salts through the'P-B'method. Finally, through orthogonal test, a set of fermentation technology was developed. Using this technology, CMCase, FPase, P-glucanase, Xylanase, Pectase, the content of the AstragalosideⅣand the content of neuter washing fiber by the numbers were tested, in different stages during fermentation. With common pathogens Proteus vulgaris,Bacillus subtilis,Salmonella typhimurium,Escherichia coli and Staphyloccocus aureus Rosenbach, the antibacterial activity of fermentation product of fungi L-6'was examined.Identification of functional strain Through traditional microstructure observation and molecular biology methods, the fungal strain L-6 was identified. The result shows that strain L-6 is Trichoderma asperellum.Conclusions T. asperellum was found in China in 2005,and was commonly reported as decay pathogens. At present the strain is less reported on the studies of producing enzymes and feed in China.That T. Asperellum L-6 can produce a plenty of enzymes was found, including cellulose enzyme, including beta-glucan decreased the enzyme, xylanolytic enzymes and pectic enzymes, etc.Using these enzymes, T. Asperellum L-6 can decompose and utilize cell wall of Chinese herbs medicine dregs,then release active residuals inside. T. Asperellum L-6 can be used in transformation and utilization of Chinese herbs'dregs. This is a new function of T. Asperellum. Therefore, T. Asperellum L-6 is a valuable microbial resource.
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