RU2323005C1 - Method for preparing xanthane thickening agent "saraksan" or "saraksan-t" - Google Patents

Abstract

FIELD: medicine, pharmacology, pharmacy.

SUBSTANCE: invention relates to a method for preparing the xanthane thickening agent for drugs and for technical aims. Method involves culturing strain-producers Xanthomonas campestris on nutrient medium comprising carbon nutrition source, mineral salts and growth factors under aeration condition. Culturing process is carried out in fermenters preliminary washed out with 0.01-0.05% of β-lactam antibiotic or antibiotic from tetracycline order, water followed by sterilization. Method provides improving quality of xanthane thickening agent.

EFFECT: improved preparing method.

4 cl, 1 tbl, 3 ex

Description

The invention relates to the field of pharmacology and relates to an improved method for producing xanthan thickener for medicinal and cosmetic products, as well as for technical purposes. It is known that bacterial exopolysaccharides, which include xanthan, are widely used as thickeners for drugs, cosmetics, and also for technical purposes, in particular, in the oil and gas industry [1, 2]. One of the important requirements for xanthan thickeners is the minimum content of microgels in xanthan solutions, which reduce the filterability of its solutions and impair practical properties.

The objective of the invention is to develop a simple, technologically advanced method for producing xanthan thickener, which makes it possible to reduce non-carbohydrate impurities as much as possible and avoid the presence of microgels in the fermentation broth, to ensure simplicity and universality of the technological design of the process.

The patent [3] describes a method for producing the Saraksan or Saraksan-T xanthan thickener by culturing the producer strain Xanthomonas campestris NRRL B-1459 (VKM B-611) on a nutrient medium containing a carbon nutrition source, mineral salts and growth factors, under conditions of aeration and stirring, followed by sterilization of the obtained fermentation solution by adding formaldehyde or powdered xanthan thickener by isolating it from the sterilized fermentation solution with isopropyl alcohol. The cultivation was carried out in fermenters, which were used for the biosynthesis of β-lactam antibiotic. After biosynthesis of the β-lactam antibiotic, the fermenter is washed with water, sterilized and used to obtain a xanthan thickener. According to this patent, in order for the quality of the xanthan thickener to decrease by no more than 20%, it is necessary to ferment Penicillium molds every 10 periodic fermentations of Xantomonas campestris bacteria in the same fermenter. In this case, sterilization of the fermenters is carried out after each fermentation of the xanthan thickener.

It was unexpectedly found that the synthesis of xanthan gum in fermenters, during sterilization of which they use a 0.01-0.05% aqueous solution of the β-lactam antibiotic or 0.01-0.05% aqueous solution of the antibiotic from the tetracycline group before washing with artesian water, or a mixture of these solutions in any ratio, allows you to activate the synthesis of xanthan gum and improve the filterability of the fermentation solution. At the same time, there is no need to use fermentation equipment, raw materials and energy for the synthesis of penicillin, and the quality of the xanthan thickener is constant and does not depend on the fermentation number. As a producer strain of Xantomonas campestris, strain NRRL B-1459 (VKM B-611) can be used.

A method for producing a Saraksan or Saraksan-T xanthan thickener is described by cultivating Xantomonas campestris producer strains on a nutrient medium containing a carbon nutrition source, mineral salts and growth factors, under conditions of aeration and mixing, followed by sterilization of the resulting fermentation solution with formaldehyde or isolating it from a sterilized fermentation solution with isopropyl alcohol. The cultivation is carried out in fermenters, which are pre-washed sequentially with 0.01-0.05% solution of β-lactam antibiotic or 0.01-0.05% solution of the antibiotic from the tetracycline group or a mixture of them in any ratio, with water, sterilized and used for the subsequent receipt of xanthan thickener.

The invention is illustrated by the following examples.

Example 1: After the liberation of the fermenter (SA-203), in which xanthan was synthesized, the apparatus was washed from the previous charge with a 0.01% aqueous solution of benzylpenicillin, artesian water, followed by sterilization under standard conditions. The seed is transferred from the seed. Sucrose 1000 kg, potassium phosphate 50 kg, 1% yeast autolysate 500 l, drinking water up to 50,000 l are used as raw materials. The fermentation temperature is 24 C. pH 6.8-7.0. The duration of the process under conditions of aeration and mixing is 72 hours. At the end of the process, the fermentation solution is heated to 75-80 ° C and 0.2-10 g / l formaldehyde is added. The obtained xanthan thickener is a jelly-like mass containing up to 15 g / l of xanthan polysaccharide, formaldehyde, protein substances and intracellular polysaccharides as fragments of bacterial cells, the remains of a carbon nutrition source and nutrient salts (The technical name of the xanthan thickener obtained in this way in the form of a fermentation solution is "Saraksan"). In dry form, a xanthan thickener is obtained by adding isopropyl alcohol to Saraxan in a ratio of 1: 4 with stirring, followed by separation of the precipitated precipitate, washing it with isopropyl alcohol, drying and grinding. The obtained powdery xanthan thickener contains up to 75% xanthan polysaccharide, up to 15% moisture, the remains of protein components, inorganic salts, the protein-formaldehyde complex (the technical name for the thus obtained powdery xanthan thickener is Saraksan-T).

Example 2. The process is carried out similarly to Example 1 in fermenters, washed sequentially with a 0.04% aqueous solution of doxycycline hydrochloride, water and sterilized under standard conditions.

Example 3. The process is carried out similarly to Example 1 in fermenters washed sequentially with an aqueous solution containing 0.03% benzylpenicillin and 0.02% doxycycline hydrochloride, water and sterilized under standard conditions.

Obtained by fermentation in reactors washed sequentially with an aqueous solution of a β-lactam antibiotic or an aqueous solution of an antibiotic from the tetracycline group, and a formaldehyde-stabilized fermentation solution (Saraksan) has a viscosity of 3500-3550 mPa · s at a shear rate of 5.4 s ^-1 . 1% solution of "Sarasan-T" in 0.1 N. KCl has a viscosity of 2900 MPa · s at a shear rate of 5.4 s ^-1 . The viscosity of the resulting solutions is almost constant for all fermentations.

The table gives comparative data on the filtration ability of fermentation solutions obtained using a xanthan producer VKM B-611 strain in fermenters, in which, after each fermentation, they were successively washed with antibiotic solutions, water and sterilized under standard conditions, as well as data on the filtration ability of dry samples isolated from appropriate fermentation solutions. For filtering, filters of the Millipor brand were used.

As follows from the table, the filterability of fermentation solutions obtained by the proposed method is identical to the filterability of enzymatic solutions obtained in fermenters in which the synthesis of β-lactam antibiotic was preliminarily carried out. In this case, in contrast to the prototype, a decrease in filterability with an increase in the number of fermentations is not observed. A similar effect is observed for solutions of dry xanthan samples isolated from the corresponding fermentation solutions. The data obtained show that the proposed method allows to obtain high quality xanthan thickener with stable properties.

Filtration time (s) of xanthan thickener samples (sample volume 200 ml) through a Millipor filter with a diameter of 47 mm. Strain - X. campestris VKM B-611.

Table Fermentation number Pore Size 5 μ Pore Size 1.2 μ by the proposed method prototype by the proposed method prototype I. Fermented solution, diluted in half (amount of xanthan - 7.5 g / l 1st f-tion 12.1 11.9 64.3 63.0 4th f-tion 11.8 12.9 63.9 66,2 8th f-tion 12,4 13,4 65.0 71.2 11th f-tion 12.0 15,5 65.0 81.9 P. Rr of dry sample 7.5 g / l in 1% NaCl + 0.1% CaCl ₂ 2nd f-tion 12.8 13,2 66,2 70.0 11th f-tion 13.0 15,5 67.0 102.3

LITERATURE

1. RF patent No. 2093143, A61K 9/00, 1991.

2. RF patent No. 1389683, A3, 1983.

3. RF patent №2252033, А61К 47/36, С12Р 19/06 2004.

Claims (4)

1. A method of producing a xanthan thickener by culturing Xanthomonas campestris producer strains on a nutrient medium containing a carbon nutrition source, mineral salts and growth factors, under conditions of aeration and mixing, followed by sterilization of the resulting solution by adding formaldehyde, characterized in that the cultivation is carried out in fermenters which pre-washed sequentially with a 0.01-0.05% aqueous solution of a β-lactam antibiotic or a 0.01-0.05% aqueous solution of a tetracycline antibiotic or and x with a mixture at the same concentration in any ratio, with water and sterilized. 2. The method according to claim 1, in which the powdered xanthan thickener is isolated from the fermentation solution with isopropyl alcohol. 3. The method according to claims 1 and 2, in which the β-lactam antibiotic is benzylpenicillin. 4. The method according to claims 1 and 2, in which the antibiotic of the tetracycline genus is doxycycline hydrochloride.