摘要
采用中心组合设计和响应面方法 ,研究了无溶剂体系中脂肪酶催化共轭亚油酸(CLA)与油脂反应的主要影响因素。建立了二级响应面模型 ,模型的复相关系数为0 90。甘油酯中CLA含量随温度、反应时间、底物配比增加而提高 ,反应时间影响最为显著。水分含量对酸解反应具有负影响 ,反应温度及反应时间与水分含量有交互作用。优化的反应条件为 :反应时间 8～ 10h ,温度 4 0～ 4 5℃ ,酶量 2 0 0U / g油脂 ,底物配比 1:2 5 ,水含量 1 0 %。在优化条件下 ,红花油中共轭亚油酸含量可达 31 4 7%。脂肪酶催化 10 ,12 十八碳二烯酸反应优于 9,11 十八碳二烯酸。
Modified safflower oil was produced vice acidolysis reactions of safflower oil and conjugated linoleic acid(CLA) by lipase from Candida antarctica (Novozym 435) in free solvent. Response surface methodology base on central composite rotatable design was used to evaluate the influence of five major factors and their relationships. The effects of reaction time, temperature, substrate ratio, enzyme amount, water content on the acidolysis were investigated. The best fitting quadratic response surface model was determined by regression and backward elimination. The coefficient of determination (R 2) of the model is 0.90. The incorporation of CLA increases with temperature, time and substrate ratio. But water content has negative effect. The interactive effects of time temperature and water time are found to be significant. The optimal conditions generated from models are temperature, 40～45℃; reaction time, 8～10h; substrate ratio, 2.5:1; water content, 1.0%. The content of CLA is 31.47% when lipase catalyzed acidolysis carried on 10 h at the same time. The substrate selectivity of the lipase had been examined in the acidolysis of CLA isomers. The lipase has a preference for the 10,12 octadacadienoic acid than 9,11 octadacadienoic acid.
出处
《高技术通讯》
EI
CAS
CSCD
2002年第9期78-82,共5页
Chinese High Technology Letters
基金
863计划 (2 0 0 1AA62 0 5 0 2 )
