Study On The Water Retention And Skin Care Of Cod Skin Collagen Peptide

Aquatic collagen is a collage extracted from aquatic animals. Our country isextremely rich in fishery resources, but it also generated a lot of fish waste。Codskin is a good material to extract collagen. Collagen makes up more than70%ofits dry skin. In this study, collagen extracted from cod skin is taken as the rawmaterial. Different molecular weight collagen peptides are obtained fromcollagen by hydrolysis and separation. Study on the effect of water retention,skin care and transdermal absorption were carried out.This paper aimed tobroaden the research field of aquatic waste,and provide experimental evidencefor developing moisturizing products and promoting high-value aquatic productindustry.Peptide hydrolyzed is extracted from cod skin gelatin by alkaline protease atdifferent time. Five collagen peptides of different molecular weight (Mr>10kDa，6kDa<Mr<10kDa，3kDa<Mr<6kDa，1kDa<Mr<3kDa，Mr<1kDa) areobtained by separation and purification, freeze drying. The purity of peptides arearound90%. Collagen and collagen peptides are carried in vitro moistureabsorption and moisture retention studies.The results show that the smallermolecular weight, the better moisturizing effect. The Mr<1kDa peptide has thebest moisturizing effect. Surface moisture experiments further confirmed theabove conclusion.The transdermal absorption experiment discuss the effects of differentfactors on the percutaneous absorption of collagen peptides and collagen.Fromthis research we find that lower molecular peptides shows better quality ofpercutaneous absorption. Unit area cumulative amount of each sample increasesover time. Transdermal kinetic equations are obtained from the transdermalabsorption curve after2h.The transdermal absorption of collagen peptidesimprove with the concentration increaseing. Collagen exhibits best transdermal absorbability in slightly alkaline conditions. In vivo percutaneous absorptionexperimental use fluorescein FITC labeled Mr<1kDa,3kDa<Mr<6kDa, Mr>10kDa peptides and gelatin to observe collagen penetration in the skin byfluorescence microscopy. It was found that the fluorescence intensity in the skinis gradually increased over time. Fluorescence distribution is consistent withcollagen transdermal absorption. Low molecular weight peptides enter throughthe stratum corneum barrier into skin first with the fastest speed. The maximummolecular weight collagen enter into the skin lastest and shows the slowestdiffusion.We also found that not all the collagen enter into skin.Some of themremain outside of skin.With the collagen entering into skin,they together play therole of moisturizing and skin care to skin.The subcutaneous injection of D-galactose on the back can induce dry andaging mice skin model. We use this model to investigate the skin moisturizingeffect and mechanism of low molecular weight aquatic collagen peptides. It isfound that low molecular weight collagen peptides have a good effect to improveaging skin’s moisture and collagen content,in which Mr<1kDa collagen peptidesplay the most obvious effect.Low molecular weight collagen peptides also havegood free radical scavenging ability.They can increase the SOD and decreaseMDA in the skin effectively. Mr<1kDa collagen peptide can effectively inhibitthe decrease of hyaluronic acid. By observing the appearance of the mouse skinand internal tissue,it is found that the low molecular weight collagen peptide caneffectively repair the skin problems such as roughness, laxity, wrinkles, reductionof collagen fibers etc. caused by aging skin.The Mr<1kDa collagen peptide are made into moisturizing cream whichcontains a single moisturizing ingredient.Its sensory andphysical,chemicalindicators conform to national standards requirements of emollient cream quality.Aging mice model confirms this collagen peptide moisturizing cream cansignificantly increase moisture content, hydroxyproline, hyaluronic acid in theskin.It also play a good effect to keep the skin moist and healthy. By observingthe appearance of the mouse skin,it is found the collagen peptide moisturizing cream can effectively repair the skin problems such as dry, laxity, wrinkles etc.Observing skin tissue, collagen moisturizing cream can effectively repair thesubcutaneous tissue disorders caused by aging. Obviously, cod skin collagenpeptide is a substance with multiple protective functions on the skin. It has a highvalue in cosmetics,not only in moisture retention,but also in resisting to thedamage caused by the aging of the skin.