NANTONG ZILANG BIOPHARMA TECH CO., LTDH3-R50We specialize in producing various grades of amino acids, such as L-tryptophan, L-leucine, L-isoleucine, L-valine, L-proline, L-glutamine, L-ornithine hydrochloride, L-citrulline, L-arginine, L-ketoglutaric acid, L-peptide, glutamine, L-theanine, L-threonine, L-lysine, DL-methionine, L-phenylalanine, DL-phenylalanine, L-arginine, and L-arginine hydrochloride. Our quality standards comply with USP, AJI, CP, and EP.