Study On Ethanol Production From Dioscorea Zingiberensis By Fermentation

Dioscorea Zingiberensis is the most important plant for extracting diosgenin in China and diosgenin is the fundament material for synthesizing hormonal medicine and thus demanded widely in the world. In order to exploit and realize comprehensive utilization of Dioscorea Zingiberensis resources, the feasibility of utilization of starch contained in Dioscorea Zingiberensis and the optimum conditions of process fermentation ethanol from Dioscorea Zingiberensis was investigated due to the percentage of 45～50 starch contained in Dioscorea Zingiberensis.The pasting propriety of Dioscorea Zingiberensis was studied by measuring the viscosity of pasting process of Dioscorea Zingiberensis and pasting temperature rang is 81℃～90℃.The condition of liquefaction and saccharification for ethanol fermentation from yam was investigated under different factors and its curves of liquefaction and saccharification were studied. The results demonstrated that the slurry, with the ratio of raw material to tape water 1:5(w/w), was well liquefied at 90℃within 30 min when addingα～amylase 10ul and almost completely saccharified at 60℃within 90 min when supplementing 60ul glucoamylase after adjusting pH. The conversion of starch involved in yam using enzyme was feasible and the significantly effect on the conversions was achieved.The conditions of alcohol fermentation of Dioscorea Zingiberensis and the process of fermentation were also analyzed. The results showed the alcohol yield of starch was 53.5% while the optimum conditions were as follows: saccharification period 40min, inoculation 0.05 %(w/w), fermentation temperature 34℃, fermentation period 60h. Alcohol production utilizing starch in Dioscorea Zingiberensis by fermentation was feasible and well effect was obtained. On the basis of experiment data of Dioscorea Zingiberensis batch fermentation, the kinetics model was proposed and the parameters of them were estimated using MATLAB software.substrate consumption modelcell growth modelproduction formation modelThe kinetics models well fitted the batch fermentation process of ethanol from Dioscorea Zingiberensis and it would be useful for further study in the larger scale of fermentation.