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Cordyceps militaris is a precious medicinal fungus which is rich of functional and physiological active substances such as cordycepin, exopolysaccharides and so on. It achieved effects of the disease prevention and control mainly through enhanced immunity, anti-oxidation, anti-stress response and anti-tumor. In order to probe the influence of different light treatments on main product and to use fermented product of Cordyceps militaris as feed additive in the preliminary feeding experiment. The effects of exopolysaccharide, Cordycepin and Cordycepic acid production and the enzyme activity of SOD were studied by the solid-fermentation conditions of Cordyceps militaris. The results were obtained as follow:1. Effects of carbon sources, nitrogen sources, the content of fish meal powder, the content of monopotassium phosphate, inoculation quantity, seed age and fermentation time on the fermentation products of Cordyceps militaris such as exopolysaccharide, cordyceps and cordyceps acid as well as the enzyme activities of SOD were studied by using single-factor experiment and orthogonal test. The results showed that the optimal fermentation conditions were as follows:the ratio of rice powder to rice bran was90:10, the contents of fish meal powder, KH2PO4and MgSO4.7H2O was1.5%,0.25%and0.15%; the ratio of substrate to water was1:1, the initial pH value was6.0, the inoculation quantity was8.0%, the seed age was4days and the fermentation time was11days. Under these conditions, the yields of water-soluble exopolysaccharide, cordycepin and cordyceps acid reached38.77mg/g. dry substract,6.71mg/g. dry substract and7.39mg/g. dry substract, the enzyme activity of SOD reached5268.3U/g.min.2. Effects of light treatment and light treatment after completion of fermentation on the main composition of solid-state fermentation were studied. The results showed that it was unnecessary to use light treatment during the solid-state fermentation process, however, once fermentation was complete, culturing the material for8days with4000Lx light treatment was necessary in order to improve the yield of cordycepin.3. Based on the optimal fermentation process, the method of solid thin layer fermentation was used to carry on the amplification production test. The results showed that, compared with the optimized results, the average yields of exopolysaccharide, cordyceps and cordyceps acid decreased only2.27%,4.32%and2.98%, while the enzyme activity of SOD increased0.31%. 4. Using the castraled growing pigs of castration Duroc×Landrace×Yorkshire as experimental materials, fermented products of Cordyceps militaris were used as feed additive in the breeding test. The results showed that, compared with the control, with the addition of5%and3%, the relative weight increase rates of pigs reached13.95%and7.23%per day; the conversion rate of feed increased11.6%and4.4%.
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