Department of Chemistry, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
Department of Chemistry, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
Carbohydr Polym. 2015 Dec 10;134:709-17. doi: 10.1016/j.carbpol.2015.08.036. Epub 2015 Aug 17.
In the present study, we have synthesized biocompatible hybrid blend of cellulosic polymers of hydroxypropyl-methyl-cellulose (HPMC) and chitosan (CHY) for the immobilization of Candida rugosa lipase (CRL). The immobilized biocatalyst HPMC:CHY:CRL was subjected for characterization such as SEM, TGA, water content analysis, lipase activity, specific activity and protein content analysis. The kinetic parameter study (Rmax/Km) demonstrated improved biocatalytic activity of lipase after immobilization on carbohydrate co-polymers of HPMC:CHY. This biocatalyst was then employed to study practical biocatalytic applications for kinetic resolution which provided 50% conversion and >94% enantiomeric excess of substrate/product (ees/eep). The protocol demonstrated excellent recyclability upto five cycles. Finally, we studied influence of immobilization on cellulosic polymers for substrate, structure and reactivity for kinetic resolution. Hence, we investigated R0 (initial reaction rate), E-value (enantioselectivity) and Ea (activation energy). This study confirms that, lipase immobilized on carbohydrate polymers had 3-4 folds higher biocatalytic activity as compared to crude CRL.
在本研究中，我们合成了羟丙基甲基纤维素（HPMC）和壳聚糖（CHY）的细胞聚合物的生物相容性混合共混物，用于固定化皱褶假丝酵母脂肪酶（CRL）。固定化生物催化剂 HPMC：CHY：CRL 进行了表征，如 SEM、TGA、含水量分析、脂肪酶活性、比活性和蛋白质含量分析。动力学参数研究（Rmax/Km）表明，在碳水化合物共聚物 HPMC：CHY 上固定化后，脂肪酶的生物催化活性得到了提高。然后，该生物催化剂被用于研究动力学拆分的实际生物催化应用，提供了 50%的转化率和底物/产物的 >94%对映体过量（ees/eep）。该方案证明了高达 5 个循环的优异可回收性。最后，我们研究了固定化对纤维素聚合物的底物、结构和动力学拆分反应性的影响。因此，我们研究了 R0（初始反应速率）、E 值（对映选择性）和 Ea（活化能）。这项研究证实，与粗 CRL 相比，固定在碳水化合物聚合物上的脂肪酶的生物催化活性高 3-4 倍。
