摘要
Kojic dipalmitate(KDP) was synthesized by the way of esterification ofpalmitic and kojic acids in organic solvent, with double-lipase as the biocatalyst. Four commercially available lipases(Amano PS, Novozym 435, Lipozyme TL IM and Lipozyme RM IM) were used to group six double-lipase combinations. These combinations were studied and Amano PS-Novozym 435 was found to have the best efficiency and was selected for optimizing the reaction conditions. The optimal reaction conditions were as follows. The mass ratio ofAmano PS to Novozyme 435 was 1:1.5, with stirring speed of 500 r/min, substrates molar ratio of 1:2, 50 ℃, 5%(mass fraction) catalyst dosage of kojic acid quantity and using acetone as co-solvent. Under these conditions, the diesterification of C5 and C7 hydroxyl groups of kojic acid molecule could be well catalyzed by double-lipase and realize a high KDP yield of 85%.
Kojic dipalmitate(KDP) was synthesized by the way of esterification ofpalmitic and kojic acids in organic solvent, with double-lipase as the biocatalyst. Four commercially available lipases(Amano PS, Novozym 435, Lipozyme TL IM and Lipozyme RM IM) were used to group six double-lipase combinations. These combinations were studied and Amano PS-Novozym 435 was found to have the best efficiency and was selected for optimizing the reaction conditions. The optimal reaction conditions were as follows. The mass ratio ofAmano PS to Novozyme 435 was 1:1.5, with stirring speed of 500 r/min, substrates molar ratio of 1:2, 50 ℃, 5%(mass fraction) catalyst dosage of kojic acid quantity and using acetone as co-solvent. Under these conditions, the diesterification of C5 and C7 hydroxyl groups of kojic acid molecule could be well catalyzed by double-lipase and realize a high KDP yield of 85%.