METHOD FOR PREPARING PROTEASE BASIC INHIBITOR FROM CATTLE ORGA Russian patent published in 2004 - IPC

FIELD: biotechnology, biochemistry. SUBSTANCE: invention relates to technology for preparing proteases Kunitz inhibitor from cattle organs and can be used in biochemistry, cellular and molecular biology, and medicinal industry as a substance used for preparing medicinal preparations. Method involves milling the parent raw, its extraction with acid an aqueous solution and purification of the end product by chromatography method using cation-exchange resins. After extraction stage impurities are precipitated in alkaline medium at temperature from -4^oC to +30^oC bringing about pH value of solution firstly to 9.5-11.3 and after removing the precipitated deposit to pH value 2-8 with acid. Isolation is carried out by solid-phase extraction on sorbent of reversed-phase type by portion accumulation of the end product with periodic washing a sorbent with buffer solution. The final purification of the end product is carried out on carboxymethylsilica gel followed by additional washing with alcoholic solution and the following desorption with 0.2-2 M solution of phosphates, sulfates, halides being mainly chlorides, alkaline, earth-alkaline metals, ammonium or their mixture. Method provides significant elevating the yield of the end product and significant reducing volumes of extract at initial stages and enhancing degree of purity of the end product. EFFECT: improved preparing method. 10 cl, 7 ex