Studies On Simultaneous Saccharification And Lactic Acid Fermentation Of Rice Straw

Plant carbohydrate, the major reservior of fixed carbon in nature, is made up of cellulose, hemicellulose and lignin. The degradation of rice straw is required the cooperation of cellulase and xylanases. In this study, producing high eco-1, 4- B -D-glucanase , A Trichoderma Reesei-T-LSQ-18 is screened, which is isolated from nature and mutated by UV-ray,Co-ray and NTG. The solid fermentative medium of T-LSQ-18 and SP-77 is opitized. Through experiments of degrading race straw by different ratio fermentative mixture between T-LSQ-18 and SP-77, the effeciency of degrading race straw is the best when the ratio of T-LSQ-18 and SP-77 is six to one. Analysis of mono-sacchrides and di-sacchrides in enzyme degradative liquor by high pressure liquid chromatography,comparison of X-ray diffraction of race straw crystalline intensity before and after incubation with cellulases, scanning electron microscopy(SEM)investigating micrographical changes of rice straw structure after incubation with cellulases,reflect the cooperation of cellulases from different sides.The conditions of Simultaneous Saccharification and Lactic acid fermentation of rice straw is optimized in 100mL and 150mL trigonal tank. Though batch cultivation, the fermentative condition of Simultaneous Saccharification and Lactic acid fermentation of rice straw in BIOF-2000 10L tank fermentaor is optimized by experients of temperature,pH,stirred rate and dissolved oxgen. At last,the weight of rice straw decreases 35.2 per cent,and the productivity of Lactic acid reach 22.3 g/L.