METHOD FOR OBTAINING HYALURONIC ACID Russian patent published in 2023 - IPC C08B37/08 

FIELD: medicine; cosmetology; veterinary medicine.

SUBSTANCE: method for producing hyaluronic acid has been proposed. Cock's combs or umbilical cords that have been bled and washed with water are homogenized, then the raw material is extracted with physiological solution for 15 minutes at 80-90°C and raw material:saline ratio 1:5. Next, separate the precipitate by filtration or centrifugation, frozen to -20-(-40)°C and incubate for 5 hours. Then fill with saline solution at a raw material:saline solution ratio of 1:5, heat to 80-90°C and keep for 15 minutes at a given temperature, separate again the precipitate by filtration or centrifugation, and keep the supernatant. With the sediment, the procedure of freezing and extraction with hot saline solution is repeated three more times. The supernatant obtained in this way is combined, phosphate buffer is added to pH7, and the protein contained in the extract is hydrolyzed with trypsin 250 USP units/mg for 2 hours at 37°C in an amount of 0.03% of the initial weight of cock’s combs or umbilical cords. Next, hyaluronic acid, freed from proteins, is precipitated with a 1-2 vol.% aqueous solution of acetic acid, the resulting precipitate is separated by centrifugation at 7000 rpm for 10 minutes, then the precipitate is dissolved in distilled water at a sediment:water ratio of 1:2 and neutralized caustic soda solution to a pH value of 7.0-7.3, heated to 80-90°C and filtered, the filtrate is frozen and further lyophilized.

EFFECT: increasing the yield of hyaluronic acid to 5.6% of the initial mass of raw materials and obtaining a preparation of non-depolymerized and protein-free hyaluronic acid with a content of the target substance of at least 94%.

1 cl, 2 tbl, 2 ex