Succinic acid is an alpha,-dicarboxylic acid resulting from the formal oxidation of each of the terminal methyl groups of butane to the corresponding carboxy group. It is an intermediate metabolite in the citric acid cycle. It has a role as a micronutrient, an anti-ulcer drug, a nutraceutical, a radiation protective agent and a fundamental metabolite. It is an alpha,omega-dicarboxylic acid and a C4-dicarboxylic acid. It is a conjugate acid of a succinate(1-). Succinic acid is a crystalline organic acid which occurs in living tissue as an intermediate in glucose metabolism.

L-proline is pyrrolidine in which the pro-S hydrogen at position 2 is substituted by a carboxylic acid group. L-Proline is the only one of the twenty DNA-encoded amino acids which has a secondary amino group alpha to the carboxyl group. It is an essential component of collagen and is important for proper functioning of joints and tendons. It also helps maintain and strengthen heart muscles.