REACTIVITY AND PRODUCTIVITY OF ESTERIFICATION CATALYZED BY LIPASES IN BIOCOMPATIBLE NANO-SCALE ASSEMBLAGES

在生物相容的纳米体系，即微乳液(反胶束)和基于微乳液的有机凝胶体系中，考察了脂肪酶催化脂肪酸酯化反应的活性和产率。微乳液体系在糖酯和聚甘油酯作为生物相容性两亲物形成的微乳液体系中，测定了脂肪酶(Mucor miehei和Rhizopus delemar)的最大反应速度是两亲性和水浓度的函数。用动力学参数评价了催化剂的催化活性。微乳相与反相水相接触回收脂肪酶。研究结果表明，这些体系是回收脂肪酶后的有效反应介质。微乳液有机凝胶体系在添加明胶形成的卵磷脂微乳液有机凝胶中，固定化脂肪酶(假丝酵母、爪哇毛霉、根霉和德尔玛根霉)的最大反应速率与水、明胶和卵磷脂的浓度有关。通过计算有效因子，将反应性估计为凝胶颗粒半径的函数。在间歇反应和连续反应中，固定化脂肪酶活性得到了较长时间的保存，并获得了较高的转化率。研究结果表明，该体系是脂肪酶催化脂肪酸酯化反应的有效固定化介质。微乳液的微观结构和性能通过测量电导率来研究微乳液的微观结构和性能。微乳液之间的相互作用随操作温度的变化而显著变化。这种相互作用因电解质和酶在微乳液水相中的增溶作用以及有机溶剂的种类而不同。

The reactivity and productivity of fatty acid esterification catalyzed by lipases were investigated in the biocompatible nano-scale assemblages, i.e. microemulsion (reverse micelle) and microemulsion-based organogel systems.1. Microemulsion systemIn the microemulsion systems formed by sugar ester and polyglycerol ester as biocompatible amphiphiles, the maximal reaction rate of lipases (Mucor miehei and Rhizopus delemar) was determined as a function of the amphiphile and water concentrations. The catalytic activity was evaluated in terms of the kinetic parameters. The lipases were recovered by contacting the microemulsion phase with a stripping aqueous phase. The findings show that these systems are an effective reaction media following the recovery of lipase.2. Microemulsion-based organogel systemIn the lecithin microemulsion-based organogels formed by the addition of gelatin, the maximal reaction rate of immobilized lipases (Candida rugosa, Mucor javanicus, Rhizopus arrhizus and Rhizopus delemar) was determined as a function of the water, gelatin and lecithin concentrations. The reactivity was estimated as a function of the radius of gel particle by calculating the effectiveness factor. In the batch and continuous reactions, the immobilized lipase activity was well preserved over a long period, and a high level conversion was attained. The findings show that this system is an effective immobilized media for fatty acid esterification catalyzed by lipase.3. Microstructure and properties of microemulsionsThe microstructure and properties of the microemulsions were investigated by measuring electric conductivity. The interaction between the microemulsions markedly changed by the operational temperature. The interaction differed with the solubilization of electrolytes and enzymes into the microemulsion water phase and the species of organic solvent.