Enzymatic Preparation Of Alkyl Polyglycoside And Its Antibacterial Properties

The yield of corncob xylan are abundant,but the utilization rate is low.Alkyl Polyglycoside is a new generation of green surfactant.Since it's environment-friendly property,APG was widely used now.But the traditional glycoside compound synthesis method has many shortcomings.Because of it's hydrolytic activity and transglycosylation.So,it is very safe and effective to use xylanase to synthetic APG.This research focus on the preparation of different length of carbon chain APG,try to find best preparation conditions,octanol and corn cob xylan and under the action of xylanase synthetic.Then,try to find out the physicochemical property,antioxidate activity and antibacterial activity of octyl alkyl polyglycoside and propyl alkyl polyglycoside.The concrete content is as follows:1,The synthesis of octyl alkyl polyglycoside.Since the hydrolytic activity is the foundation of transglycosylation activity.First step is study on the hydrolytic activity of xylanase.In this study,corncob used as substrate,through the DNS method to determinte the reducing sugar concentration of the enzymatic hydroysate.Baesd on the DNS result,the best contiditon of the hydrolytic activity is under 70?,the hydrolysis time is 6h,the buffer is pH6.0,the substrate concentration was 3%,the enzyme amount is 140U/g.By the result of thin-layer chromatography,the best synthesis conditions of octyl alkyl polyglycoside is under 70?,reaction time is 3 hous,the buffer is pH6.0,the substrate concentration is 45mg/ml,the enzyme amount is 140U/g.The result provide certain theoretical basis for the industrial production.As for the emlsibility and foam properties.Based on the result,the octyl alkyl polyglycoside has good emlsibility and foam properties,so,it can used as surfactant.2,The synthesis of propyl alkyl polyglycoside.By the result of thin-layer chromatography,the best synthesis conditions of propyl alkyl polyglycoside is under 70?,reaction time is 3 hous,the buffer is pH6.0,the substrate concentration is 45mg/ml,the enzyme amount is 140U/g.The result provide certain theoretical basis for the industrial production.As for the emlsibility and foam properties.Based on the result,the emlsibility and foam properties of propyl alkyl polyglycoside was weak,so,it can not used as surfactant.3,The antioxidate activity and the antibacterial activity of octyl alkyl polyglycoside and propyl alkyl polyglycoside.Through the DPPH·scavenger effect study,when the clearance rate reach 80%,the concentration of octyl alkyl polyglycoside and propyl alkyl polyglycoside are all lower than 0.3mg/mL.Through the ·OH scavenger effect study,when the clearance rate reach 80%,the concentration of octyl alkyl polyglycoside and propyl alkyl polyglycoside are all lower than 0.3mg/mL.The antioxidate activity of the octyl alkyl polyglycoside and propyl alkyl polyglycoside are all very good.Through the plate bacteriostatic experiment,the results show that the octyl alkyl polyglycoside and propyl alkyl polyglycoside all have stronger antibacterial activity on escherichia coli and staphylococcus aureus.After 24h,the minimum inhibitory concentration(MIC)results shows the MIC of octyl alkyl polyglycoside on E.coli is 5mg/ml,the MIC of octyl alkyl polyglycoside on S.aureus is 5mg/ml,the MIC of propyl alkyl polyglycoside to E.coli is 7.5mg/ml,the MIC of propyl alkyl polyglycoside to S.aureus is 5mg/ml.