Research On Enzymatic Hydrolysis Of Cellulose In Reverse Micelles By Different Surfactants Of Technology

With the development of bio-engineering and materials science, the reverse micelle technology in the world has been widespread concerned.Reverse micelle, the system is a surface active agent dispersed in organic medium to form self-assembled nano-sized colloidal dispersion system of water in oil, which is stabilized by surfactant molecules. Reverse micelles have a hydrocarbon chain amphiphilic molecules composed of the shell, point hydrophobic organic solvent, the polar head pointing to the formation of polar aggregates within the cavity, water-soluble nano-sized cavity in the polar form a "small pond." Reverse micellar polar core in the physical properties of water and normal water is different from its higher viscosity, while the acidity and polarity of the water than the normal low. Therefore, the "pool" some of the original soluble in water insoluble substances. In addition, the surfactant molecules to avoid the presence of membrane around the enzyme and organic solvent exposure, protection of the enzyme active site, it is not because of contact with the organic solvent inactivation, thereby enhancing the catalytic performance. Reverse micelles as enzyme reaction medium has many advantages, making the reverse micelles in the enzyme-catalyzed reactions is very wide, so the reverse micellar system of catalytic reaction that micellar enzymology become a hot research one. In recent years, by adding surfactants to improve the efficiency of enzymatic hydrolysis more and more attention. Biosurfactant-based reverse micellar system construction and in this environment for enzymatic degradation reaction has been reported rarely.Several types of surfactants were adopted to construct reverse micelles,in order to investigate the characteristics of cellulose hydrolysis,we used the carboxymethyl cellulose as substrate. The electrical conductivity was measured to determine the maximum water solubilization W₀（W₀ = [H₂O] / [SA]）of CTAB, SDS, Tween 80 and rhamnolipid reverse micellar systems were 15.2,20.1,2.3and40.3.In this condition we studied the effects of surfactants concentrations and cellulose dosage on the enzymatic hydrolysis of reverse micelle,and compared with aqueous systems. It was shown by the results that when the cellulose dosage was 0.15FPU/g substrate, the maximum yield of reducing sugar in reverse micelles was obtained at 1cmc of CTAB, SDS, Tween 80 and rhamnolipid, in which the rhamnolipid yield was highest of 198.03mg/g substrate.When the concentrations of CTAB, SDS, Tween 80 and rhamnolipid were 1cmc,the productions of reverse micelles systems were higher than aqueous systems of 34.36%, 21.24%, 11.44%and34.62%.In the optimum conditions of the surfactant concentration, taking the saving cost and sugar yield into consideration, the cellulose dosage of 5FPU/g substrate was the most suitable. The reducing sugar’s yield of biosurfactant rhamnolipid reverse micellar system was higher than those of three chemical surfactant systems, it was shown that the adoption of biosurfactant has technologically promising prospect in constructing reverse micelles and enhancing the stability of reverse micelles.