Study On Fermention Technology Of Sorgo Straws By Pleurotus Ostreatus And Antioxidant Effect Of Polysaccharide From Pleurotus Ostreatus

Pleurotus ostreatus which can be able grow on sorgo straws powder medium was selected among15 pleurotus ostreats including P-1,P-2,P-3,P-4,P-5,P-6,P-7,P-8,P-9,P-10,P-11,P-12,P-13,P-14,P-15. The Pleurotus ostreatus selected can produce more polysaccharide and have strong ability to degradate lignin. The optimum medium for both liquid strain and solid fermentation were studied. The best dosage of maize powder,wheat barn powder,soybean powder and sorgo straws powder was obtained by measuring biomass and polysaccharide of culture.by both single factor and orthogonal experiments.The experiment for the optimal conditions of solid fermentation was conducted. The antibacterical effects,antioxidant ability and reductive ability of polysaccharide which was extracted from fermentated sorgo straws powder were studied.The results showed that the optimum medium for liquid strain was as follows: soyben powder 10-15g/L, sorgo straws powder 2g/L, maize powder25g/L,wheat barn powder 25g/L.The biomass and polysaccharide can reach as high as 20.74mg/mL and 20.81mg/mL after 5d fermentation under the conditions used.The best solid fermentation medium: soyben powder 10%,sorgo straws powder 70%,maize powder10%,wheat barn powder 10%. The optimal culture conditions were as follows:water 65%,fermentation temperature 26℃,pH 5,culture time 5 d,medium layer 2cm.The polysaccharide have strongly antibacterical effects on Escherichia coli and S.aureus. Their scavenging activity to superoxide radical had a better scavenging effectiveness.The polysaccharide to colon bacillus, salmonella, etc have strong inhibitory effect. When the concentration of polysaccharide 4mg/mL of the clearance is 34.3%, when the concentration of polysaccharide 8mg/mL of the event, a high clearance, When the concentration of more than four mg/mL of the clearance, when the concentration of 10 mg/mL of the clearance,·OH topped 76.2 %, When the concentration of polysaccharide 1-3 mg/mL of the dynasty, when DPPH·23.7 % rise from 41.8 %, as to the concentration of 5 mg/mL, when the clearance of DPPH·50.6 %.