Study On Solid-State Fermentation Of Rhizopus Chinensis For Production Of Fibrinolytic Enzyme By Using Soybean As Substrate

Solid-state fermentation of Rhizopus chinensis TK317 by using soybean as substrate produce protease which can hydrolyze soybean proteins to soybean peptides. Recently researching show that soybean peptides can debase cholesterin, and can restrain hoist of blood pressure, and can buildup immune function, and so on.The dissertation focuses on the optimization of solid-state fermentation condition of Rhizopus chinensis for producting fibrinolytic enzyme by using soybean as substrate of on the base of prevenient experimentation, and extraction of fibrinolytic enzyme was carried out. The result of the optimization of solid-state fermentation of Rhizopus chinensis indicated: the appropriate component of culture medium were the proportion of common flour and soybean 1:9, additive water 0.75mL per gram materiel and initial pH 5.0; and the appropriate conditions of cultivation were fermentation time 60h, temperature 28°C, and inoculum size 10~7 spores per gram materiel. Average fibrinolytic enzyme activity reached 480.52U/g materiel under optimized conditions.The dissertation based on solid-state fermentation condition of Rhizopus chinensis by using soybean as substrate can produce soybean peptides which have the fibrinolytic activity. The upper liquid of milling slurry through adding water and freezing centrifugation was soybean peptides A including fibrinolytic enzyme, and the soybean peptides B was the dry medium by enzyme hydrolysis. The range of molecular weight of soybean peptides was analysed by Sephdex G-25 and SDS-PAGE.The enzyme was purified with ultrafiltration concentration and ammonium sulfate fractionation. The specific activity was 1588.03U/mg with 329.47 times purification. The purified enzyme was homogeneous as examined by SDS-PAGE.The amino acids sequence of the purified enzyme was analysed by two-dimensional electrophoresis and MS/MS. By calculation the sequence of the three peptides were (A)SPHSKGFDHR, (B)GDTKPHNPGSSR, and...