Lipase-catalyzed in situ reactive extraction of oilseeds with short-chained alkyl acetates for fatty acid esters production

Substituting short-chained alkyl acetates for short-chained alcohols as acyl acceptors for fatty acid esters production, the negative effects of glycerol and alcohol on lipase can be eliminated. Short-chained alkyl acetates, like other short-chained esters, are also suitable solvents for seed oil extraction. Thus, methyl acetate and ethyl acetate were adopted as extraction solvents and transesterification reagents at the same time for in situ reactive extraction of Pistacia chinensis Bunge seed and Jatropha curcas L seed in this work. Fatty acid methyl esters and ethyl esters were, respectively obtained with higher yields than those achieved by conventional two-step extraction/transesterification. The improvement ranged from 5.3% to 22%. The key parameters such as solvent/seed ratio and water content were further investigated to find their effects on the in situ reactive extraction. The highest P. chinensis Bunge and J. curcas L methyl/ethyl esters could attain 92.8%, 89.5%, 86.1% and 87.2%, respectively under the optimized conditions.