D-Serine
Serine plays an important role in various biosynthetic pathways. In addition, it is the precursor to a number of amino acids like Glycine and Cysteine. Besides, it also helps an enzyme catalyze its reaction - the hydrolysis of peptide bonds in polypeptides and proteins, which is basically a major function in the digestive process.Serine is also known for assisting in production of immunoglobulins and antibodies for a healthy immune system, as well as for helping in the absorption of creatine that helps build and maintain the muscles.