	US 12,391,744 B1
	Micromolecular type III collagen peptide capable of promoting secretion of type III and IV collagens, and preparation method therefor
Aiqing Liu, Beijing (CN); Jingqi Liu, Beijing (CN); Haiyan Wang, Beijing (CN); Mingkang Lei, Beijing (CN); Xiaoqing Zhang, Beijing (CN); Shuang Liu, Beijing (CN); Pengcheng Li, Beijing (CN); and Xinyu Ma, Beijing (CN)
Assigned to BEIJING SEMNL BIOTECHNOLOGY CO., LTD., Beijing (CN)
Filed by BEIJING SEMNL BIOTECHNOLOGY CO., LTD., Beijing (CN)
Filed on Aug. 21, 2024, as Appl. No. 18/810,577.
Claims priority of application No. 202410182043.X (CN), filed on Feb. 19, 2024.
Int. Cl. C07K 14/78 (2006.01); C07K 1/34 (2006.01)

CPC C07K 14/78 (2013.01) [C07K 1/34 (2013.01)]

6 Claims

1. A method for preparing a micromolecular type III collagen peptide, comprising the following steps:

step (1), pretreating livestock and poultry skin, sequentially comprising: first water washing, sodium chloride solution soaking, sodium hydroxide solution soaking and second water washing, wherein the pH value and the electrical conductivity in the second water washing are adjusted;

step (2), enzymatically hydrolyzing the livestock and poultry skin treated in step (1) by using a combined enzyme, and filtering an enzymatic hydrolysate to obtain a clear liquid;

step (3), decoloring and filtering the clear liquid obtained in step (2), exchanging water until the solid matters is 0, and performing nanofiltration to obtain a high-concentration solution;

step (4), sterilizing and drying the high-concentration solution obtained in step (3) to obtain a coarse powder; and

step (5), superfinely grinding the coarse powder obtained in step (4) and sieving same to obtain a finished product, namely the micromolecular type III collagen peptide, wherein

in step (1), the livestock and poultry skin is from livestock and poultry at the age within 180 days; and the livestock and poultry skin is selected from rabbit skin, pig skin, cow skin or chicken skin;

in step (1), the mass ratio of the material to water in the first water washing and the second water washing is 1: (4-5); tap water is used for the first water washing; and purified water is used for the second water washing and stirring is performed during the second water washing;

in step (1), the mass fraction of the sodium chloride solution is 1%-2% and the soaking time of the sodium chloride solution is 1-2 h; and the mass fraction of the sodium hydroxide solution is 2%-3% and the soaking time of the sodium hydroxide solution is 2-3 h;

in step (1), the pH value is 6-7 and the electrical conductivity is 230-260 μs/cm;

in step (3), the high-concentration solution is a solution with the solid matters of 30%-35%;

in step (2), the combined enzyme consists of the following enzymes: a protease derived from Bacillus licheniformis, a protease derived from Bacillus subtilis and a protease derived from Aspergillus niger; the weight ratio of the protease derived from Bacillus licheniformis, the protease derived from Bacillus subtilis and the protease derived from Aspergillus niger is (20-80):(60-80):(1.5-3);

in step (2), the addition amount of the combined enzyme is 0.815%-1.615% by weight of the livestock and poultry skin; and the enzymatic hydrolysis is performed at the pH of 6-8 and 50-60° C. for 2-4 h, and the temperature is raised to 80-85° C., maintained for 10-15 min and lowered to 50-55° C.; and

wherein the micromolecular type III collagen peptide comprises SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8.