Studies On Skin Care Characteristics And Whitening Mechanism Of The Composite Of Silk Fibroin Oligopeptide With Cordyceps Militaris Polysaccharide

Silk fibroin has good skin affinity,anti-bacterial,moisturizing,anti-ultraviolet and non-irritating properties,and is a high-quality raw material for the production of cosmetics.However,natural silk fibroin has a high molecular weight and is not easily absorbed by human skin,which limits its excellent skin care properties.Cordyceps militaris polysaccharides,as one of the main active components of Cordyceps militaris,have significant antioxidant and free radical scavenging capacity.In order to provide technical support for the development of silk skin care cosmetics with excellent antioxidant properties,we prepared a small molecule silk fibroin peptide that was easily absorbed by the human body by studying enzymatic hydrolysis;Preparation of silk fibroin oligopeptide-Cordyceps militaris polysaccharide composite and studied its skin care properties(whitening,moisturizing,anti-oxidation,anti ultraviolet);To explore the whitening mechanism of silk fibroin oligopeptide-Cordyceps militaris polysaccharide composite.The following results have been obtained:1.Preparation of silk fibroin oligopeptide and Cordyceps militaris polysaccharideSilk fibroin protein was obtained from silkworm cocoon after de-sericination.Silk fibroin was degummed,hydrolyzed by CaCl2 salting,alkaline protease enzymatic hydrolysis and other processes,oligopeptides with relative molecular weight of 239.06-644.57 Da were obtained.Cordyceps militaris polysaccharides were obtained by ethanol degreasing,hot water extraction,alcohol precipitation,protein and impurities removal.The extraction rate was 8.75%,and the sugar content was 90.7%.2.Preparation of silk fibroin oligopeptide-Cordyceps militaris polysaccharide compositeThe silk fibroin oligopeptides were tested for skin care properties such as whitening,anti-ultraviolet,moisturizing and anti-oxidative activities,and compared the effects of different doses of silk fibroin oligopeptides.The optimal skin care concentration was 10 mg/ml after weight analysis.At this concentration,the tyrosinase inhibition rate was 90.58%,the ultraviolet light transmittance was 35.56%,the water evaporation was 21.19%,and the superoxide anion clearance rate was 24.51%.On the basis of 10 mg/ml silk fibroin oligopeptide,Cordyceps militaris polysaccharides of different concentrations were complexed.The skin-care properties of the composite showed that its moisture retention,anti-ultraviolet radiation and anti-oxidation ability were obviously enhanced.The optimum concentration of Cordyceps militaris polysaccharides was 6 mg/ml by weight analysis.At this concentration,the tyrosinase inhibition rate of the composite was 95.09%,the superoxide anion clearance rate was 53.34%,and the water evaporation rate was 53.The emission is 17.08% and the ultraviolet transmittance is 1.69%.3.Whitening mechanism discussion of silk fibroin oligopeptide-Cordyceps militaris polysaccharide compositeThe silk fibroin oligopeptide-Cordyceps militaris polysaccharide composite was prepared with 10 mg/ml silk fibroin oligopeptide and 6 mg/ml Cordyceps militaris polysaccharide.The effects of the composite on B16 melanoma in mice were studied.The cell morphology,cell viability,tyrosinase activity,melanin content and the expression of related genes were analyzed,and the whitening mechanism was discussed.The results showed that the silk fibroin oligopeptide-ascaria polysaccharide composite significantly inhibited the growth of B16 melanoma cells,the inhibition rate of intracellular tyrosinase was 63.25%,the inhibition rate of melanin content was 46.86%,the inhibition rate of cell viability was 42.48%,and the expression levels of MITF,TYR and TRP-1 were down-regulated by 42.17%,88.97% and 63.35%,respectively.Silk fibroin oligopeptide-Cordyceps militaris polysaccharide composite played a whitening role by inhibiting the expression of MITF,TYR and TRP-1 genes and inhibiting the activity of tyrosinase.