Optimized Conditions for the Production of Hydroxamic Fatty Acids from Coconut Oil by a Lipase from Rhizopus delemar

Abstract

Alipase from Rhizopus delemar was used as a biocatalyst for the synthesis of hydroxamic fatty acids (HFA) by reacting hydroxylamine with coconut oil, methyl laurate and lauric acid. The effects of various reaction parameters such as amount of hydroxylamine-HCl, incubation time, temperature, and amount of enzyme were evaluated to achieve high product yield.

The reaction products were monitored by Thin Layer Chromatography using hexane: diethyl ether: acetic acid (20:80:1 v/v/v) as solvent system. Identification of the products was done by Gas-Liquid Chromatography. Analysis revealed a mixture of HFA produced using coconut oil as substrate: 30.33% myristylhydroxamic acid (MHA), 24.17% olelyhydroxamic acid (OHA) and 45.50% laurylhydroxamic acid (LHA). On the other hand, methyl laurate and lauric acid yielded only LHA.

Purification of the product was done by crystallization in hexane at 14 °C. Identification of the functional groups present was determined by Infrared (IR) spectroscopy.