Premium
High yields of ascorbyl palmitate by thermostable lipase‐mediated esterification
Author(s) -
Bradoo S.,
Saxena R. K.,
Gupta R.
Publication year - 1999
Publication title -
journal of the american oil chemists' society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.512
H-Index - 117
eISSN - 1558-9331
pISSN - 0003-021X
DOI - 10.1007/s11746-999-0141-0
Subject(s) - ascorbyl palmitate , lipase , palmitic acid , chemistry , ascorbic acid , yield (engineering) , solvent , catalysis , triacylglycerol lipase , chromatography , hexane , enzyme , organic chemistry , fatty acid , food science , materials science , metallurgy
High yields of ascorbyl palmitate (6‐ O ‐palmitoyl‐l‐ascorbic acid) were obtained by lipase‐mediated esterification using Bacillus stearothermophilus SB 1 lipase. The final yield was greatly influenced by the initial water content of the system, quantity of enzyme, and molar ratio of palmitic acid to l‐ascorbic acid. Reaction rates increased directly with temperature from 40 to 100°C. Maximum conversion (97%) was achieved after 30 min at 100°C (solvent‐free), 1 h at 80°C (solvent‐free), and 2 h at 60°C (solvent/hexane). The synthesis was scaled up to 1‐l volume with 95% conversion using 50 mmoles of ascorbic acid and 250 mmoles of palmitic acid in hexane. Similar yields of ester were obtained in five repetitive cycles using 5 g enzyme immobilized on Accurel. The present B. stearothermophilus SB 1 lipase was a more efficient catalyst for the synthesis of ascorbyl palmitate than other commercial lipases.