Studies on Isolation and Screening of Palatinose Producing Strain and Process Improvement

• Main Authors: Chu , Chun-Yao, 朱鈞耀
• Other Authors: Yuan-Chi Su
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/64979925329589486693

碩士 === 國立臺灣大學 === 農業化學研究所 === 87 === Palatinose, structural isomer of sucrose, is a sweetner which can prevent cavity. The general production method is transfer sucrose to palatinose by microbial glucosyltransferase; in industry, palatinose is produced by flowing sucrose solution to the bioreactor packed with immobilized cells. The purpose of this study is isolating and screening the high active palatinose producing strains from nature. We expect to isolate palatinose producing strains for industrial purpose. After isolation and screening, strain No. 48 was obtained and was suggested as Klebsiella pneumoniae NTU-48. The optimal medium compositions for K. pneumoniae NTU-48 to produce palatinose were: tryptic soy broth, 3%; surcose,8%; yeast extract, 5%; NaH2PO4‧2H2O, 0.5%. When a shaking culture was carried out with a optimal medium at 30oC, 125rpm for 18 hours, it was found that a maximum palatinose producing activity. Agitation and surface aeration influence the palatinose producing activity of K. pneumoniae NTU-48 in 6-Liter fermentor. The cultivation has a maximum palatinose yield (82%) with 200 rpm of agitation speed and 1.5 vvm of surface-aeration when it was carried out in a 6-Liter fermentor with the optimal medium under 30oC for 18 hours' cultivation. The maximum palatinose producing activity is obtained with 3% of sodium alginate as immobilized material at 40oC of its optimal temperature. The recovery rate of palatinose is up to 56% after sucrose solution is reacted with immobilized cells, heated until condense to 80% of original solution, and added organic solvent.