As a non protein active amino acid, D-TRYPTOPHAN has special physiological properties. It can be used as non nutritive sweetener, feed additive and plant growth agent in food and feed industry and agriculture. In the pharmaceutical industry, it is mainly used to synthesize various peptides to replace L-tryptophan, prolong the half-life of peptide drugs and reduce side effects, It is an important synthetic precursor of enzyme inhibitors. It can improve the immune ability of the body and delay the occurrence of allergic reaction. Most polypeptide antibiotics can inhibit or kill Gram-positive bacteria, while others can inhibit or kill Gram-negative bacteria such as Pseudomonas aeruginosa, mycobacteria, fungi, bacteria, bacteria and tumor cells. The side chain of semi synthetic antibiotics synthesized from D-TRYPTOPHAN plays an important role in its pharmacological function, and the peptide bond is difficult to be identified β- In addition, it has a wide antibacterial spectrum, low toxicity, low anaphylaxis, fast absorption, high blood concentration, long duration of drug strength and so on.