DE2248843C3 - Process for the production of lysozyme, from protein - Google Patents

Description

The invention relates to a method for obtaining lysozyme from protein.

The isolation of lysozyme was carried out by Fleming because of the strong unspecific immunological effect of this compound to its extensive Use as a medicament for the treatment of viral and bacterial infections in humans. Lysozyme was a. also as an anti-inflammatory agent and as an agent to stimulate leukocyte formation used. For parenteral administration, therefore, constantly increasing amounts of lysozyme with high Activity and great purity are required.

In GB-PS 11 10466 a process for the production of lysozyme from protein is described, after which native protein with a weakly acidic ion exchanger at pH 6 to 7 and temperatures Treated below room temperature and the ion exchanger is separated. Then be Protein contamination from the ion exchanger with a maximum of 0.2 molar salt solution with a pH 7 or less eluted. The lysozyme is then eluted with an aqueous salt solution and removed from the obtained eluate precipitated by increasing the salt concentration. One of the advantages of this procedure is that the protein that remains after the lysozyme has been separated is neither diluted nor contaminated and closed Can be used for feeding purposes.

Since lysozyme in the protein in amounts of 0.3 ins 0.5 Percentage by weight is included and, for certain therapeutic treatments, considerable amounts are included in In some cases up to 1 g / day or more of very pure lysozyme are required, it can be seen that for Very large amounts of protein have to be processed to meet the needs. This inevitably leads to numerous problems, e.g. B. in storage, freezing and transport, and of course to an increase in the price of the end product.

The object of the present invention was therefore to provide a simple and economical process for production to provide high quality lysozyme that has the aforementioned disadvantage «* does not have. This object is achieved by the invention

solved.

The subject matter of the invention is thus the subject matter defined in the claims.

In the process according to the invention, the aqueous solution obtained during the elution of the ion exchanger can be used Lysozyme solution can be concentrated, with concentrating takes place by ultrafiltration. In this way, a considerable part of the failure of the Lysozyme from the eluate required salt, e.g. ammonium sulfate, saved.

It should also be noted that in the known method, the lysozyme in the last stage is precipitated from aqueous solutions by adding salts, whereby a certain amount of these Salts, e.g. B. sodium chloride remains in the end product. In the process according to the invention, however, it succeeds. Produce lysozyme with a very low salt content if the lysozyme solution is dried before a Is subjected to ultrafiltration.

The ultrafiltration is already on a large scale z. B. Used in sugar refining to concentrate solutions and in wastewater treatment been.

Egg white contains proteins with low molecular weights, such as lysozyme, and with much higher ones Molecular weights such as ovalbumin, conalbumin, ovomucoid and avidin. These proteins are dissolved in an aqueous medium that also has compounds with contains a great deal of low molecular weights, such as glucose, and inorganic ions.

The protein can vary depending on the membrane used, the pressure applied and the number of the circulations are concentrated up to 3 times or more, the lysozyme content of the Protein increases to 0.9 percent or more.

Above, some of the levels achieved by reducing the original protein volume have already been achieved Advantages described. Another, even more important advantage is that in the inventive used ultrafiltration a large part of the glucose, which is the browning of the dried Protein is removed. The remaining concentrated protein can under considerable Heat saving dried or processed by other methods, with one for Feed usable by-product is obtained.

In the method according to the invention are as semipermeable Membranes, in particular made of organic polymers, e.g. made of vinyl and cryopolymerisates, existing membranes preferred. However, numerous other types of membranes can be used provided they have a pore size such that proteins, including lysozyme, are retained while water, glucose and inorganic ions pass through the membrane.

The examples illustrate the invention.

example

52 kg of native protein are adjusted to pH 6 to 7 with dilute hydrochloric acid or acetic acid and then concentrated by ultrafiltration to a lysozyme content of about 0.9 to 13 percent by weight The concentrated solution obtained is mixed with 15 liters of a weakly acidic ion exchanger adjusted to pH 6 ^ treated. The temperature of the mixture is kept at 0 to 5 ° C until the lysozyme concentration in the protein concentrate dropped to 100 to 150 mcg / ml

Ion exchanger is separated and with

Claims (2)

Patent claims: 1. A method for obtaining lysozyme from protein, characterized in that one the lysozyme concentrated in the egg white by ultrafiltration of the egg white so that the obtained Concentrate with a weakly acidic ion exchanger at pH 6 to 7 and temperatures below Treated room temperature that after separating the ion exchanger from this Protein contamination with a salt solution of 0.2 molar or less with a pH of 7 or less eluted that you then the lysozyme from the ion exchanger with an aqueous salt solution eluted and that the lysozyme from the eluate obtained by increasing the salt concentration fails 2. The method according to claim 1, characterized in that the eluate containing the lysozyme concentrated before the precipitation of the lysozyme by a second ultrafiltration.