ingredient information
L Cystine
Cysteine is a sulfur-containing amino acid that occurs naturally in foods and can also be manufactured by the body from the amino acid methionine. In the production of cysteine, methionine is converted to S-adenosyl methionine (SAM), which is then converted to homocysteine. Homocysteine then reacts with serine to form cysteine. Cysteine is also found in the body and in food as cystine, an amino acid that contains two cysteines joined together. How it Functions What is the function of cysteine? Promoting Antioxidant Activity As a key constituent of glutathione, cysteine has many important physiological functions. Glutathione, formed from cysteine, glutamic acid, and glycine, is found in all human tissues, with the highest concentrations found in the liver and eyes. Glutathione is a potent antioxidant, protecting fatty tissues from the damaging effects of free radicals. The antioxidant activity of glutathione is attributed specifically to the presence of cysteine in the compound. Source: