Production of xylitol by immobilized yeast cells

• Main Authors: Kaun-Ben Chen, 陳觀彬
• Other Authors: Wen-Chang Liaw
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/54084061463037157527

碩士 === 國立雲林科技大學 === 工業化學與災害防治研究所碩士班 === 89 === Production of xylitol by immobilized yeast cell Student：Kaun-Ben Chen Advisors：Dr. Wen-Chang Liaw Institute of Industrial Chemistry and Hazards Prevention National Yunlin University of Science & Technology ABSTRACT This study deals with production of xylitol from rice straw. Straw was first treated with sulfuric acid, the result indicates that the best condition for hydrolysis is using 2% H2SO4 and heat the straw at 126℃for 60min.Througth this treatment 13.3g of xylose can be obtained from 100g of rice straw. Xylose thus obtained is further decolorized with activated charcol and pH adjusted to remove the salts. Meanwhile, the yeast strain-Candida subtropicalis is immobilized and entrapped in the hydrophilic acrylic resin matrix using photopolymerization method. The immobilized cells are then used to ferment xylose to xylitol. As for immobilization with photo-crosslinking, the raw material used are acrylic monomer such as polyethylene glycol diacrylate ( PEG-DA) and 2-hydroxyethyl methacrylate (HEMA).To these substances were added with 1% Benzoin isopropyl ether(photo-semsitizer agent)and yeast cells. The membrarce thus formed has a thickness of 0.2mm and in the 10% culture medium it will product the highest amount of xylitol with a yield of 70%. The immobilized yeast cells are them treated batchwise for endurance. Result indicates that it is fairly stable for 1~2 months with a yield exceeds 60%.