Research On Suger Plant Fiber Hydrolysis

In this thesis, beet residue, bagasse, and sweet sorghum straw were used as materials;different methods were adopted to hydrolyze those materials in order to produce morefermentable sugars for bioethnal production.Cellulase and xylanase can hydrolyze sugar plant residue to glucose and xylose.The bestenzyme producing strain of these five Trichoderma viride F244, Trichoderma virideF106,Trichoderma viride L19, Trichoderma viride L21, Trichoderma viride AS3.2876fermented on the substrate of sugar beet residues and under the condition of28℃,5dayscultivation was determined by testing xylanase and cellulose activity.AS3.2876fermented on Solid-state fermentation on the substrate of sugar beet residuesammonium sulfate as nitrogen source, the optimum medium moisture content of80%28°C5days cultivation, under this condition, the maximum enzyme activity was obtained.Under the optimal cultivating condition, AS3.2876produced enzyme were extracted andused for hydrolyzing sugar beet,bagasse, sweet sorghum straw residue at50°C,48h ofhydrolysis reaction,The hydrolysis rates were33.67%,12.19%,3.57%, respectively.Commodity cellulose and xylanase were also used in hydrolyzing those sugar plantfiber raw materials， the hydrolysis rates were33.67%,26.03%,10.59%, respectively.For certain raw material sugar beet residue, the hydrolysis ratio of enzyme fermented byAS3.2876and commodity enzyme were of the same level, that means AS3.2876have apotential capability for suger beet residue hydrolyzing in the future study.Ultrasonic-assisted pretreatment of sugar plants fiber was studied in this thesis. Theresults indicated that the hydrolysis rates of sugar plants were improved by ultrasonic. Andwith1%dilute sulfuric acid, the hydrolysis rates were52.91%,51.4%, and48.1%,respectively.Total hydrolysis rates were83.32%，79.70%，73.07%respectively.The structure of sugar plant fiber was destroyed by ultrasonic.And the rates of sugarplants were improved too. This thesis gives reference for full utilizing sugar plants.It wasdeemed that ultrasonic-assisted pretreatment of sugar plants fiber then hydrolysis was a better way for full use of sugar plants.