Lactobionic acid (4-O-β-galactopyranosyl-D-gluconic acid) is a sugar acid. Lactobionic acid is a disaccharide formed from gluconic acid and galactose.Lactobionic acid can be formed by oxidation of lactose. The carboxylate anion of lactobionic acid is known as lactobionate.

1. Lactobionic acid reduces the appearance of lines and wrinkles, discoloration, enlarged pores and roughness through gentle exfoliation.

2. Lactobionic acid is a potent antioxidant that has been shown to target naturally-occurring, skin degrading enzymes to help maintain a youthful look.

3. Lactobionic acid is a super powered chelator and humectant, protecting skin and attracting moisture to the delicate barrier for added hydration boosting and comfort.

Lactobionic acid can form salts with mineral cations such as calcium, potassium, sodium and zinc. Calcium lactobionate is a food additive used as a stabilizer. . Mineral salts of lactobionic acid are also used for mineral supplementation.

Lactobionic acid  is also used in the cosmetics industry as an antioxidant and in the pharmaceutical industry as an excipient for formulation. For example, the antibiotic erythromycin is used as the salt erythromycin lactobionate when intravenously delivered.