酶法合成麦芽糖醇脂肪酸单酯的抑菌性

Study on antibacterial activity of maltitol laurate synthesized by enzyme

采用脂肪酶NOV435催化麦芽糖醇分别与4种脂肪酸（月桂酸、辛酸、油酸和硬脂酸）反应合成相应的麦芽糖醇脂肪酸酯,并经分离纯化制备获得高纯度的单酯产品,测定了它们在0.0625~6 mg/mL质量浓度下对不同细菌和酵母的抑菌率及低抑菌浓度（MIC）。结果表明,麦芽糖醇脂肪酸单酯具有良好的抑菌性能,对枯草芽孢杆菌和变异链球菌显示出很强的抑制作用,对大肠杆菌有较好的抑制效果,对酵母菌也有定抑制能力。比较不同脂肪酸酰基麦芽糖醇单酯的抑菌性发现,月桂酸单酯抑菌能力强,辛酸单酯和油酸单酯次之,硬脂酸单酯较弱。麦芽糖醇月桂酸单酯对大肠杆菌、枯草芽孢杆菌和变异链球菌的MIC值分别为2.0 mg/mL、0.5 mg/mL和0.25 mg/mL,具有比麦芽糖和蔗糖等亲水基月桂酸单酯更好的抑菌性。

Monoacyl maltitols were synthesized from maltitol and four fatty acids（ lauric acid,octanoic acid,oleic acid and stearic acid） by NOV435 lipase-catalyzed method.High purity of monoacyl maltitols was obtained by silica gel column seperation and semi-preparation HPLC.The inhibition rates and minimum inhibition concentration（ MIC） of monoacyl maltitols against bacterials and yeast at 0.062 5 ~ 6 mg/mL were investigated.The resultsshowed thatmonoacyl maltitols possessed excellent antibacterial activity,strong inhibition against Bacillus subtilis and Streptococcus mutans,good inhibitory effect on Eschericheae coli,and depressing against Yarrowia lipolytica to some extent.Among the monoacyl maltitols with differentfatty acidacyls,mono lauroyl maltitol presented the strongest antibacterialability, mono octanoyl maltitol and mono oleoyl maltitol took the second,and mono stearoyl maltitol had relatively weak inhibition activity.The MIC of mono lauroyl maltitol against Eschericheae coli,Bacillus subtilis and Streptococcus mutans were 2.0 mg/mL,0.5 mg/mL and 0.25 mg/mL,respectively,which had the better antibaterial activity compared to mono lauroylmaltoseand mono lauroyl sucrose.