DL Proline and its derivatives are often used as asymmetric catalysts inorganic reactions. The CBS reduction and proline catalysed aldol condensation are prominent examples. L-Proline is an osmo protectant, and therefore is use din many pharmaceutical, biotechnological applications. DL-Proline is a racemic mixture of proline, an imino acid. Proline is found in cartilage and is important for maintaining youthful skin as well as repair of muscle, connective tissue and skin damage. It is also essential for the immune system and an essential component of collagen and is important for proper functioning of joints and tendons. Proline is important for the proper functioning of joints and tendons and helps maintain and strengthen heart muscles.