Jarrow Formulas Alpha Lipoic Acid, manufactered in Europe, is a disulfide molecule (containing two thiol groups). A thiol (or -SH) consists of a sulfur and a hydrogen atom. This unique antioxidant is both lipid and water soluble, a potent promoter of glutathione and an important co-factor in energy metabolism. Biotin is an essential cofactor of intracellular carboxylase enymes and is important for energy production and lipid metabolism. Biotin is added for optimum ALA activity.