Extraction Of Phytoglycogen And Its Application In Cosmetic

Phytoglycogen(PG)is a hyperbranched glucan which is very different in structure and physicochemical properties from other natural high molecular polysaccharides.Due to its reactive groups and dendritic nanoparticle structure,ability to maintain low viscosity at high concentrations,there is a potential for PG to be used in cosmetics.This paper explored the application of PG in encapsulation of sunscreen and in shampoo as conditioner,provided some scientific basis for its application on cosmetics.Firstly,PG was extracted from sweet corn kernels,and the extraction conditions of the process were optimized by single factor experiment.The optimized extraction condition was: the ratio of material to liquid was 1:5(g/mL),the temperature was 8°C,the time was 8 h,and both adjusting pH and boiling were used to remove protein,then the extraction rate of PG reached at 13.58%,purity?95%.The structure,physicochemical properties of PG were studied by using high-performance anion exchange chromatography,infrared spectroscopy,nuclear magnetic resonance etc.The results showed that the PG was composed of ?-1,4 glycosidic bonds,and ?-1,6 glycosidic bond constitutes a branched chain,and the particle diameter ranging from 30 to 100 nm.PG solution showed low viscosity even in a high concentration.Further,PG exhibited excellent moisturizing properties in environments with relative humidity of 43% and 81%.Secondly,the avobenzone(AVO)molecules were embeded on the surface of PG particles or within a certain depth by different methods.The embedding efficiency and the photostablility of the complex on AVO was also analyzed.The complex(PG-AVO-1-a)prepared by the anti-solvent method could make the concentration of AVO in water approach to 137.88 ?g/mL,while the solubility of the unembedded AVO in water was only 1.7 ?g/mL.This indicated that PG has enhenced the water solubility of AVO by nearly 81 times.DSC and XRD was used to character the PG-AVO-1-a,it was confirmed that AVO was embeded in the PG particles in the form of small molecule,and there was little AVO crystal.Compared the photostability of AVO in the complex and in the oily solvent,it was found that the photodegradation rate of AVO in the complex was remarkably lowered.By measuring the PFA value of sunscreen,it was proved that adding PG alone to sunscreen can act as a photostabilizer,while only 0.041% of AVO dissolved in water delivered from PG-AVO-1-a could increase PFA value by 32.4%,and maintained photostability.Finally,2,3-epoxypropyltrimethylammonium chloride(GTA)was used as a quaternization agent to prepare the cationic phytoglycogen(PG-GTA).Used single-factor experimental analysis to obtained the optimal conditions,under the condition of sodium hydroxide mass concentration of 0.3%,reaction temperature of 50 °C,reaction time of 2 h,GTA and PG mass ratio of 1.2,the PG-GTA with the degree of substitution of 0.294 could be prepared.The interaction between PG-GTA with anion surfactant sodium lauryl sufate(K12)and Sodium lauryl polyoxyethylene ether sulfate(AES)was investigated.When the anion surfactant concentration is higher than its crital micelle concentration(cmc),the PG-GTA could form transparent solution with K12 and AES,wheras,the system formed flocculation due to strong static interaction when dilute to solution concentration below to anion surfactant cmc.The combing performance of the shampoo added with PG-GTA was studied,and the combing work was reduced to 31.29% compared with the shampoo without PG-GTA.These results showed that PG-GTA has potential to be used in shampoo as conditioner.