Research On The Lipase-catalyzed Synthesis And Surfactant Property Of Starc Sugar Fatty Acid Ester

Starch sugar fatty acid ester as a non-ionic surfactant, is a kind of novel emulsifyingagent that is being developed. Its research and development adds a new kind of esterproducts as emulsifier, enrichs the emulsifying agents. Now they have been widelyused in food, pharmaceutical industries and cosmetic. In the paper, method ofsynthesis was investigated from maltose and oleic acid, glucose and oleic acid in thepresence of Novozym435lipase. The purified products were analyzed by MS, IR andsurfactant properties purified products were mensurated.The effect of the ratio of raw material, the temperature, the consumption of solventand enzymes, and time of reaction is discussed. The optimum conditions of synthesiswere determined as follows：glucose:oleic acid was1:1.5（the mole ratio）, acetone20mL acetone/1mmol oleic acid, Novozym435lipase0.36g/1mmol oleic acid,under the circulation refllux temperature after a reaction of42hours. The percentconversion of oleic acid of93%was achieved. maltose:oleic acid was1:1.5（the moleratio）, acetone10mL acetone/1mmol oleic acid, Novozym435lipase0.3g/1mmololeic acid, under the circulation refllux temperature after a reaction of72hours. Thepercent conversion of oleic acid of83%was achieved.The purified products were analyzed by MS, IR. IR results of glucose oleate show thatthere was a strong absorb peak in1730cm^-1plaee，IR results of maltose oleate showthat there was a strong absorb peak in1731cm^-1plaee，that it a character peak ofester。MS results of glucose oleate show that there was a strong absorb peak in467.4and MS results of maltose oleate show that there was a strong absorb peak in629.Thatmatch M of glucose oleate （444） and M of maltose oleate（606）. That proves theproducts are glucose oleate and maltose oleate.The surfactant properties of monoester and diesters were also studied. Such as HLB,critical micelle concentration, foaming ability, foam stability, emulsifying ability andemulsion stability. foaming ability of glucose oleate and maltose oleate was verygood,and their foam stability were all about80%. emulsifying ability of maltoseoleate was better than emulsifying ability of glucose oleate, The HLB of glucoseoleate was7.6, which could be used as W/O emulsifier wetting agent, while the HLBof maltose oleate was11.22which could be used as O/W emulsifier. The resultshowed that glucose oleate and maltose oleate had good surface activity.