Lipase-catalyzed Synthesis And Characterization Research Of Propylene Glycol Methyl Fumarate

As the food industry develops faster and faster, the food additives are used wildly. Besidethe ability of inhibiting the microorganism breeding, the food additive should have othercharacteristics, such as harmless for human, high effective and suitable for much food.α,β-unsaturated carbonyl is one of the functional groups which have antimicrobial activity.Dimethyl fumarate (DMF) is an effective preservative containing such functional group, but itis prohibited to be used in food because of its skin allergy.In this paper, lipase was used as catalyst to synthetize the fumarate and1,2-propyleneglycol in order to obtain a food additive having emulsibility and antimicrobial activity. Singlefactor experiments and orthogonal experiment were used to optimize the synthesis ofpropylene glycol methyl fumarate (PMF). Antimicrobial activity and surface activity wereinvestigated.LC-MS was used to prove the synthetized product. Then single factor experiments andorthogonal experiment were used to optimize the reaction parameters for improve the relativecontent of PMF, such as solvent, molar ratio of substrates, reaction temperature, enzyme dosage,concentration of substrates and reaction time. The optimal reaction conditions acquired weretertiary butanol as solvent, monomethyl fumarate:1,2-propylene glycol was1:2.0, substratesconcentration was1.0mol/L, enzyme dosage was1.2%, reaction temperature was60℃andthe duration of reaction was20h.PMF exhibited good antimicrobial activity. PMF was effective on inhibiting not onlysingle microorganism but also mixed microorganisms. The minimal inhibitory concentrationfor Escherichia coli, Bacillus subtilis, Saccharomyces cerevisiae and Aspergillus niger wererespectively0.11%,0.08%,0.07%and0.05%. Moreover, PMF was stable under heattreatment, pH and no allergy for skin.The result of surface activity showed that HLB of PMF was8.36. The surface tension ofPMF was larger than Span80when the concentration was0.1%. Emulsibility of PMF wasworse than Span80but the foaming ability and foaming stability of PMF was better.