University of Mustafa Kemal, Faculty of Arts & Sciences, Department of Chemistry, 31040 Hatay, Turkey.
Food Chem. 2012 Dec 15;135(4):2326-32. doi: 10.1016/j.foodchem.2012.07.062. Epub 2012 Jul 20.
Candida rugosa lipase (CRL) and porcine pancreatic lipase (PPL) were immobilised by entrapping and also by covalent binding for use in synthesis of isoamyl acetate (IAAc), which has a typical banana flavour. Lipase entrapment was carried out by dripping sodium alginate (Na-Alg)-chitosan (Chi)-lipase mixture into CaCl(2)-glutaraldehyde (GAL) solution to obtain Ca-Alg/Chi(CRL/PPL). Immobilisation conditions were optimised as 1.5% Na-Alg, 1.5% chitosan and 0.15% GAL. Ca-Alg/Chi(CRL/PPL) samples showed the highest activity when they were dried upon reaching 27% of their initial weights. Covalent binding was achived with Chi modified with spacerarm via glutaraldehyde to get Chi(CRL/PPL). The highest IAAc production was observed when 1,3-diaminopropane was used as a spacer arm. The best ester yield was achieved in heptane, at 40 and 45°C reaction temperatures, 50mM IAA and 50 or 75 mM AA concentrations. The amount of IAAc was nearly 10 times higher for the batch type than for the continuous packed bed column reactor.
棘状假丝酵母脂肪酶（CRL）和猪胰脂肪酶（PPL）通过包埋和共价结合固定化，用于合成具有典型香蕉风味的乙酸异戊酯（IAAc）。脂肪酶包埋通过将海藻酸钠（Na-Alg）-壳聚糖（Chi）-脂肪酶混合物滴入 CaCl2-戊二醛（GAL）溶液中进行，得到 Ca-Alg/Chi（CRL/PPL）。优化了固定化条件为 1.5% Na-Alg、1.5%壳聚糖和 0.15% GAL。当 Ca-Alg/Chi（CRL/PPL）样品达到初始重量的 27%时干燥，其表现出最高的活性。Chi 通过间隔臂与戊二醛修饰，得到 Chi（CRL/PPL），实现了共价结合。当使用 1,3-二氨基丙烷作为间隔臂时，观察到最高的 IAAc 产量。在庚烷中，在 40 和 45°C 的反应温度、50mM IAA 和 50 或 75mM AA 浓度下，获得最佳的酯产率。分批式反应器的 IAAc 量比连续填充床柱反应器高近 10 倍。
