In today’s beauty and skin care market, whitening ingredients have attracted much attention because they can help the skin restore a bright and even skin tone.
Antioxidants
Ultraviolet radiation can promote the production of reactive oxygen species (ROS), thereby activating tyrosinase and inducing melanogenesis. Antioxidants can neutralize oxygen free radicals and reduce the stimulation of tyrosinase activation; at the same time, they can hinder the oxidation reaction of tyrosinase and block the synthesis of melanin. Common antioxidants include vitamin C, vitamin E, vitamin B, glutathione, coenzyme Q10, etc.
Hydroquinone
Hydroquinone, whose chemical name is hydroquinone, is a traditional and effective whitening ingredient. Hydroquinone inhibits tyrosinase activity by binding to histidine in the active site of tyrosinase. However, hydroquinone is somewhat irritating and may cause skin erythema, burning, etc. If the concentration is too high, it is also cytotoxic, and long-term use may cause pigmentation loss, exogenous brown disease, etc.
Arbutin
Arbutin is a glycosylated derivative of hydroquinone. Compared with hydroquinone, arbutin has mild properties and less toxicity. Arbutin can competitively bind to tyrosinase within a concentration range that is not toxic to melanocytes, thereby inhibiting tyrosinase activity and reducing melanin production. Currently, arbutin and its derivatives are widely used in whitening products.
Kojic acid
Kojic acid is a fungal metabolite derived from Acetobacter, Aspergillus, and Penicillium. Kojic acid can chelate the copper atom at the active site of tyrosinase, making tyrosinase inactive. However, kojic acid has poor stability, is sensitive to light and heat, is easily chelated with metal ions, is easily oxidized and discolored, and has poor skin absorption. In order to overcome the shortcomings of kojic acid, researchers have developed a variety of kojic acid derivatives, many of which show strong whitening effects. Kojic acid dipalmitate is a popular kojic acid whitening agent, while kojic acid monolinolenate combines the whitening effects of kojic acid and linolenic acid.
Azelaic acid
Azelaic acid inhibits tyrosinase activity by preventing the active site of tyrosinase from interacting with tyrosine. At the same time, azelaic acid can block the normal transport of melanin within melanocytes, thereby reducing the formation of melanin granules. The whitening effect of azelaic acid is selective and has an inhibitory effect on highly active melanocytes, but has a limited effect on normal pigment cells.
Glutathione
Glutathione participates in the catalysis of pseudomelanin and is often added to cosmetics as a whitening ingredient. There are two forms of glutathione, namely reduced glutathione (GSH) and oxidized glutathione (GSSH). The whitening mechanism of glutathione includes: eliminating free radicals and peroxides through antioxidant means, indirectly inhibiting tyrosinase activity; binding to the active site of tyrosinase, directly inhibiting tyrosinase activity; interfering with tyrosine Transport acidase to melanin precursor bodies; promote the conversion of eumelanin to pseudomelanin; regulate the depigmentation ability of melanocytotoxic agents.
Tranexamic acid
The molecular structure of tranexamic acid is similar to that of tyrosine. It can bind to tyrosinase and occupy the melanin synthesis tools, resulting in competitive inhibition. In addition, the whitening mechanisms of tranexamic acid include: inhibiting the conversion of plasminogen to plasmin; reducing mast cell activity, reducing the release of inflammatory factors such as arachidonic acid and prostaglandin E2, and interfering with the latter to promote melanin production Function: Reduce the production of melanocyte stimulating hormone α-MSH and reduce pigment synthesis.
Plant extracts
The application of plant extracts as whitening ingredients in cosmetics caters to people’s pursuit of returning to nature. Currently, common plant extracts with whitening effects on the market include licorice extract, mulberry extract, aloe extract, green tea extract, proanthocyanidins, etc. Plant extracts have varying degrees of inhibitory effects on tyrosinase activity, and also have antioxidant and other effects. Proanthocyanidins are internationally recognized natural antioxidants that can effectively scavenge free radicals in the human body. However, plant extracts also have defects, such as poor stability, easy inactivation, and easy discoloration.
Nicotinamide
Nicotinamide is a biologically active form of niacin (vitamin B3). It can inhibit the activity of tyrosinase and the transfer of melanosomes to keratinocytes. It can interfere with the synthesis of melanin and The melanin transport process achieves the whitening effect.
Chemical peel
A chemical peel is different from the whitening process described above. Chemical peeling uses chemical damage to peel off the aging and dead superficial cuticle, and the melanin contained in it will also fall off. Chemical peeling agents accelerate the replacement of the stratum corneum and accelerate the metabolism and shedding of melanin from the epidermis, making the skin lighter and more shiny. Common chemical peeling agents include fruit acids, salicylic acid, lactic acid, etc.
By understanding these common whitening ingredients, you can more clearly choose skin care products that suit your skin needs, leaving your skin healthier and brighter.