Chemistry of ascorbic acid Haworth and Szent-Györgyi, respectively. Ascorbic acid is a vinylogous carboxylic acid and forms the ascorbate anion when deprotonated on one of the hydroxyls. This property is characteristic of reductones: enediols with a carbonyl group adjacent to the enediol group, namely with the group –C(OH)=C(OH)–C(=O)–. The ascorbate anion is stabilized by electron delocalization that results from resonance between two forms: For this reason, ascorbic acid is much more acidic than would be expected if the compound contained only isolated hydroxyl groups. The ascorbate anion forms salts, such as sodium ascorbate, calcium ascorbate, and potassium ascorbate. Ascorbic acid can also react with
Ferulic acid is an antioxidant in vitro in the sense that it is reactive toward free radicals such as reactive oxygen species (ROS). ROS and free radicals are implicated in DNA damage, cancer, and accelerated cell aging. If added to a topical preparation of ascorbic acid and vitamin E, ferulic acid may reduce oxidative stress and formation of thymine dimers in skin. There is also a small amount of research showing oral supplements of ferulic acid can inhibit melanin production in the process of skin whitening. It is used as a matrix for proteins in MALDI mass spectrometry analyses. Ferulic acid Ferulic