Attenuation of the skin barrier function causes dry skin to be an important feature of skin aging. Skin moisturizing is a result of the combination of two factors, a sebum film that inhibits water evaporation and a natural moisturizing factor that is present in keratinocytes. Collagen and elastin are two important proteins that make up the dermis of the skin. Collagen gives strength and toughness to the extracellular matrix, while elastin gives the skin elasticity. The ability of aging skin to synthesize collagen and elastin decreases, collagen fibers become thicker, and abnormal cross-linking occurs, resulting in decreased skin elasticity and increased wrinkles. Because an important way to solve the problem of skin aging is to moisturize and repair the barrier function of the skin. Below are a few natural sources of active ingredients with skin moisturizing and repairing functions.
1.3 moisturizing and repairing plant extracts
1.3.1 Cactus extract
The main chemical components of cactus extract are amino acids, superoxide dismutase, vitamin C and polysaccharides. Rich in vitamin C, it has the ability to scavenge and inhibit free radicals. It contains high-efficiency whitening and moisturizing factor, locks in moisture, maintains skin's health and whitening, and is very suitable for use in beauty cosmetics.
1.3.2 Ginseng fruit extract
The ginseng fruit extract is rich in amino acids, vitamin C, trace elements, saponin and superoxide dismutase SOD. The skin using the ginseng fruit extract emulsion has a very good moisturizing effect, and is significantly different from the glycerin and hyaluronic acid groups. The experiment also showed that the ginseng fruit extract also has a certain whitening effect, which further shows that the ginseng fruit extract has better moisturizing and whitening effect. It increases the hydration of the skin itself and strengthens the skin's ability to repair itself.
1.3.3 Pomegranate extract
The main chemical components of pomegranate extract are anthocyanins, pomegranates, polyphenols, ellagic acid, vitamin C and the like. Pomegranate contains a large amount of pomegranate polyphenols and anthocyanins. It has 3 times higher antioxidant activity than green tea and 20 times more vitamin C. It can effectively neutralize free radicals, promote metabolism and excrete toxins. Pomegranate polyphenol  has a super moisturizing effect, and its molecular structure has a large amount of phenolic hydroxyl groups. Its hydrophilicity is not only strong, but also forms with polysaccharides, polyols, lipids, proteins and peptides. A more moisturizing complex.
1.3.4 Tremella fuciformis extract heteropolysaccharide
Tremella (heteropoly) polysaccharide can increase the water concentration on the surface of the skin, forming an influx gradient from the skin; on the other hand, forming a hydrophobic barrier, reducing the loss of transepidermal water, thereby causing an increase in the surface moisture of the skin, and also forming within the absorption Flow gradient. The polysaccharide of Tremella fuciformis is directly or indirectly affected by the stratum corneum and affects the properties of protein or lipid water exchange inside the stratum corneum.