Kojic Acid

Description

Its discovery followed scientists' observation that people making sake, the traditional rice wine, had very pale hands. In 1907, they isolated the fungus responsible for producing the acid: the koji fungus.

Various moulds of the genus Aspergillus produce kojic acid from suitable nutrient solutions, including starches; dextrins; disaccharides such as sucrose and maltose; the hexoses glucose, fructose, mannose and galactose; the pentoses xylose and arabinose; and sorbitol, dulcitol, i-adonitol, inulin, inositol, glycerine, β-glycerophosphate, dihydroxyacetone, gluconic acid, tartaric acid and other substances. The highest yields have been obtained from glucose and xylose.

It is a pale yellow or beige, odourless crystalline powder, readily soluble in acetone and ethyl acetate, fairly soluble in water, somewhat less soluble in ethanol and slightly soluble in chloroform, ether and pyridine.

Properties and Uses of Kojic Acid

It is one of the most powerful depigmenting agents available.

Used to lighten melasma, lentiginosis, pigmentation caused by pregnancy or contraceptive pills, age spots, freckles and more.

It inhibits melanogenesis, or melanin production, and the resulting pigmentation. It inhibits tyrosinase by chelating the copper it contains and also induces a reduction in eumelanin in hyperpigmented cells.

It is not photosensitive, although, like all depigmenting agents, it should be applied at night, with sun protection recommended during the day. Like all acids, it is susceptible to oxidation, which would cause it to lose effectiveness.

It is also used to treat topical acne lesions, as it has a moderate antibiotic effect.

Antimicrobial and antifungal: protects against bacteria, germs and fungi.

Anti-inflammatory: reduces inflammation and prevents its appearance.

Antioxidant: keeps free radicals at bay.

It can be used to make ointments, soaps, exfoliants, bath salts, bubble baths, lotions and creams, and as an addition to some sunscreens...

Recommended Dosage

0.5-5% for topical use.

Side Effects

• May be harmful if inhaled and may irritate the respiratory tract.
• Continued use may cause skin irritation and contact dermatitis.
• May cause eye irritation.

Precautions

• Wear gloves in case of prolonged or repeated contact
• Store in tightly closed containers and protect from light.