It is the enzyme that causes the oxidation of glycolic acid [glycolate] {HOCH2COOH} to glyoxylic acid {OHCCOOH}.

U can mix tretinon with hydroquinone, but don't add glycolic acid in it... Use glycolic acid seperately and at different time.

Glycolic acid is most often used in chemical peels due to its excellent ability to penetrate skin. Glycolic acid also has many applications in chemistry, as it is an important intermediate substance in organic synthesis. Further, glycolic acid has applications in industry, where it is used to dye and tan fabrics, as well as being used as a flavoring agent and preservative.

Since the word "acid" is used in the name, you can bet it is an acid, and not a base.

Glycolic acid products are often used in skincare. Their most common application is in exfoliating products, anti - ageing products, and psoriasis treatments.