At present, the best application of polypeptide technology in China is the bioactive polypeptide produced by enzymatic method. For example, the "Sanjiu Protein Peptide" produced by Wuhan Jiushengtang is a successful case. Women drinking Sanjiu protein peptide containing small molecular active peptides can not only regulate the immune system in vivo, thus enhancing their physique, but also wash their faces in water with Sanjiu protein peptide, which is very helpful for skin health.

Sanjiu protein peptide, a small molecular active polypeptide, can whiten skin, increase skin elasticity and luster, improve skin antibacterial ability and immunity, relieve skin inflammation, heal skin wounds, reduce or eliminate skin wrinkles, and make skin smooth, moist, smooth and translucent. Middle-aged women in Yanbian area of Jilin Province, after taking Sanjiu protein peptide orally, put the packaging bottle into water and wash their faces with water for a long time. Their skin is white and red, and they look at least young 10 years old.

Many active substances in human body exist in the form of peptides. Peptides are involved in the growth and reproduction of hormones, nerves and cells. Their importance lies in regulating the physiological functions of various systems and cells in the body, activating related enzymes in the body, promoting the permeability of intermediate metabolic membranes, or controlling DNA transcription or influencing specific protein synthesis, and finally producing specific physiological effects.