Steryl and Stanyl Esters of Fatty Acids by Solvent-Free Esterification and Transesterification in Vacuo Using Lipases from Rhizomucor miehei, Candida antarctica, and Carica papaya

• Published in: Journal of agricultural and food chemistry 2001-11, Vol.49 (11), p.5210-5216
• Main Authors: Weber, Nikolaus, Weitkamp, Petra, Mukherjee, Kumar D
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and medical sciences; Biotechnology; Candida - enzymology; Chemical industry and chemicals; Chemical industry. Chemical engineering; Chromatography, Thin Layer; Esterification; Esters; Exact sciences and technology; Fatty Acids - chemistry; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Kinetics; Lipase - chemistry; Magnoliopsida - chemistry; Manufacturing and processing; Molecular Structure; Oils and fats; Rhizomucor - enzymology; Solvents
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf0107407

Sitostanol has been converted in high to near-quantitative extent to the corresponding long-chain acyl esters via esterification with oleic acid or transesterification with methyl oleate or trioleoylglycerol using immobilized lipases from Rhizomucor miehei (Lipozyme IM) and Candida antarctica (lipase B, Novozym 435) as biocatalysts in vacuo (20−40 mbar) at 80 °C, whereas the conversion was markedly lower at 60 and 40 °C. Corresponding conversions observed with papaya (Carica papaya) latex lipase were generally lower. High conversion rates observed in transesterification of sitostanol with methyl oleate at 80 °C using Lipozyme IM were retained even after 10 repeated uses of the biocatalyst. Saturated sterols such as sitostanol and 5α-cholestan-3β-ol were the preferred substrates as compared to Δ5-unsaturated cholesterol in transesterification reactions with methyl oleate using Lipozyme IM. Transesterification of cholesterol with dimethyl 1,8-octanedioate using Lipozyme IM in vacuo yielded methylcholesteryl 1,8-octanedioate (75%) and dicholesteryl 1,8-octanedioate (5%). However, transesterification of cholesterol with diethyl carbonate and that of oleyl alcohol with ethylcholesteryl carbonate, both catalyzed by Lipozyme IM, gave ethylcholesteryl carbonate and oleylcholesteryl carbonate, respectively, in low yield (20%). Moreover, cholesterol was transesterified with ethyl dihydrocinnamate using Lipozyme IM to give cholesteryl dihydrocinnamate in moderate yield (56%), whereas the corresponding reaction of lanosterol gave lanosteryl oleate in low yield (14%). Keywords: Candida antarctica lipase B; Carica papaya lipase; esterification and transesterification in vacuo; fatty acids; Rhizomucor miehei lipase; solvent-free esterification and transesterification; stanyl esters; steryl esters