【摘要】 以三棕榈酸甘油酯(PPP)和油酸(O)为原料,假丝酵母脂肪酶(Candida sp.99-125)为催化剂合成人乳脂替代品1,3-二油酸2-棕榈酸甘油三酯(OPO)。研究了Candida sp.99-125脂肪酶的催化机理、酶使用量以及Candi-da sp.99-125脂肪酶的重复使用。研究结果表明:Candida sp.99-125脂肪酶的催化机理是先酸解PPP sn-1位的棕榈酸,然后再与sn-3位的棕榈酸反应;当脂肪酶用量为37500 U,反应温度为43℃,经过3 h反应后,OPO的转化率可达41.24%;补加初次反应脂肪酶使用量50%的脂肪酶后,重新加入底物反应48 h,OPO的转化率可维持在40%左右,且平均反应速率保持稳定。更多还原

【Abstract】 The human milk fat substitute(HMFS) 1,3-oleic acid 2-palmitic acid triglyceride(OPO) has been synthesized by Candida sp.99-125 lipase-catalyzed acidolysis using palmitic acid triglyceride(PPP) and oleic acid(O) as reaction substrates.The catalytic mechanism for the action of Candida sp.99-125 lipase and the reuse of the enzyme were studied.The results showed that: the Candida sp.99-125 lipase initially catalyzes the palmitic acid at the sn-1 position,and subsequently at the sn-3 position;the OPO conversion rate approached 41.24% at a temperature of 43 ℃,with a Candida sp.99-125 lipase load of 37500U,and a time of 3h;it was possible to maintain the reaction rate close to the initial reaction rate,with the conversion ratio of the product OPO approaching 40%,by adding 50% new enzyme to recovered lipase and reacting for 48h with new substrates.更多还原