FI63243B - SAETT ATT SEPARERA BLODETS HEMOGLOBIN TILL HEM OCH GLOBIN - Google Patents

Description

63243

This invention relates to a method of separating blood hemoglobin into heme and globin by suspending the blood cells separated from the blood in an acidic aqueous solution in which hemoglobin is hydrolyzed to heme and globin by precipitating the heme and globin by precipitating the heme and separating the heme.

Blood is known to contain iron and most of this iron is present as iron protoporphyrin in hemoglobin. When plasma is separated from the blood, about 80% of the proteins in the whole blood remain in the blood cell fraction. The blood cell fraction contains about 38% crude protein, of which about 80% is dry matter hemoglobin in cattle and about 87% in pigs. Hemoglobin contains 6% heme, which still contains about 9% iron and the remaining 94% is globin. Interest in organic hemi-iron has greatly increased as some studies have found it to be better absorbed in the gut than inorganic iron compounds. In addition, many inorganic iron compounds have been found to have side effects. Due to the strong color, odor and taste of the blood cell fraction and its poor shelf life, its use as an iron medicine is out of the question.

On a laboratory scale, heme has previously been separated from globin by chromatography or extraction using methyl ethyl ketone, acetone and dimethylformamide as solvents.

The application of solvent methods on a technical scale results in remarkably high solvent and regeneration costs.

In addition, the solvents used are highly flammable and the removal of solvent residues from the final products has proved difficult if the final products are used as feed, nutrients or drugs.

63243

Swedish Offenlegungsschrift 7 407 882-5 discloses a method for separating heme from globin, in which an acidic hemoglobin solution is cooled and a large amount of ethanol is added in two steps to precipitate and separate the globin by centrifugation. The disadvantage of this method is that large amounts of solvent have to be used, which must eventually be removed from the final products. In addition, work must be performed at low temperatures, which incurs significant additional costs.

It is also known to separate blood globin from hay by chromatography with carboxymethylcellulose. In this method, the hemolyzed and acid hydrolyzed blood cell fraction is passed through an ion exchange column packed with carboxymethylcellulose, whereby the heme is adsorbed on the carboxymethylcellulose. However, this method separates such small amounts of heme from globin relative to the amount of carboxymethylcellulose used that this method is not suitable for a technical production scale.

The object of the present invention is to provide a method for separating blood hemoglobin into heme and globin, in which the above-mentioned disadvantages are eliminated and in which the end product is a heme-containing product suitable for use as a raw material in the manufacture of iron and a globin protein which can be used as a nutrient or feed ingredient without solvents. disadvantages.

The main features of the invention appear from the appended claim 1.

According to the invention, the blood cell fraction separated from the plasma is hemolyzed by diluting it with water and acid hydrolyzed by adjusting its pH to less than 3 to break the bonds between globin and heme. The heme is then precipitated from the acidic aqueous solution by adding an aqueous solution of carboxymethylcellulose (CMC) and preferably so that the weight ratio 63243 CMC / globin is at least 1:10, but preferably not more than 2:10. The iron contained in the heme is then likely to form a coordination bond with the carboxyl groups of the CMC, which are fully protonated in the pH range used in the invention. The precipitated hemi-CMC complex is finally separated from the globin protein solution, for example by centrifugation.

The invention is described in more detail below by means of examples. Example 1

The hemoglobin-containing blood cell fraction separated from the plasma is diluted with an amount of water at least twice the weight of the blood cell fraction and the pH of the resulting solution is adjusted so low by adding 0.1 M HCl that the pH of the aqueous solution remains below 3. The aqueous carboxymethylcellulose solution is added so much that the weight ratio of carboxymethylcellulose to globin protein in the aqueous solution is about 1:10. The precipitate formed is separated from the solution by centrifugation (8000 g, 15 min). The precipitate contains 1.8% iron and the light solution contains not more than 0.07% iron by weight of dry matter.

Example 2

Hemoglobin-containing blood cells isolated from plasma are slurried in water (1: 2 weight ratio). The pH of the solution is adjusted to 1.5 with 1 M HCl and five times the volume of 0.3% aqueous carboxymethylcellulose is added to the acidic aqueous solution, the weight ratio of CMC to globin protein in the aqueous solution being 2:10. The mixture is allowed to stand for 15 min and the precipitated hemi-CMC complex is separated from the globin protein solution by centrifugation for 1/2 h (8000 g). The protein fraction contains about 70% of the original globin proteins and less than 0.05% by weight of its dry matter is iron.

Example 3

Blood cells separated from plasma are diluted with water (weight ratio 4 63243 1: 3). The pH of the solution is adjusted with 1 M HCl. to 1.5 and add 4 x volume of a 0.3% aqueous solution of carboxymethylcellulose to give a weight ratio of CMC to globin protein of 1.9:10. The mixture is allowed to stand for 15 minutes and the precipitated hemi-CMC is separated. complex from the globin protein solution by centrifugation for 1/2 h (8000 g) The protein fraction contains about 70% by weight of the original globin proteins and less than 0.06% by weight of its dry matter is iron.

Example 4

Plasma-separated blood cells are diluted with water (1: 4 weight ratio), the pH of the solution is adjusted to 1.5 with 1 M aqueous hydrochloric acid, and three volumes of 0.35% aqueous CMC are added to give a weight ratio of CMC to globin of 1.7; 10. Allow the mixture to stand for 15 min and separate the precipitated hemi-CMC complex from the protein solution by centrifugation for 1/2 h (8000 g). The globin protein fraction contains about 80% of the original proteins and only about 0.07% by weight of its dry matter is iron.

Claims (3)

5 63243 A method of separating blood hemoglobin into heme and globin by suspending the blood cells separated from the blood in an acidic aqueous solution, precipitating the heme and separating the precipitate from the aqueous solution of globin, characterized in that carboxymethylcellulose is added to the acidic aqueous solution to precipitate the hemi-CMC complex. Process according to Claim 1, characterized in that such an aqueous solution of carboxymethylcellulose is added to the acidic aqueous solution that the weight ratio CMC / globin is at least 1:10, but preferably not more than 2:10. Process according to Claim 1 or 2, characterized in that the pH of the acidic aqueous solution is maintained at a value of at most about 3 during the precipitation of the heme.