DD283841A5 - PROCESS FOR THE PRODUCTION OF SODIUM GLUCONATE ON MICROBIOLOGICAL PATHS - Google Patents

Abstract

The invention relates to a process for the preparation of sodium gluconate in a microbiological manner, in which as fermentation substrate, besides / NH4 / 2 HPO4, MgSO47H2O and KH2PO4, starch hydrolyzate 5-80-DE, preferably 10-45. which contains glucose, maltose and oligosaccharides. After sterilization of the substrate and prior to inoculation with Aspergillus niger spores, at a temperature of 70-30C, enzyme supplement with glucoamylase is added. At the same time, the bioconversion of the reaction substrate with saccharification and gradual neutralization with NaOH is carried out in the bulk. The sodium gluconate prepared according to the invention is used in the food and textile industry, in household chemistry and electroplating, and in metal corrosion prevention. {Sodium gluconate production; Fermentation substrate starch hydrolyzate; Enzyme enzyme ester glucoamylase; Spores Aspergillus niger; bioconversion; Neutralization NaOH}

Description

The invention relates to a process for the preparation of sodium gluconate by microbiological means, which finds use in the food and textile industry, in household chemistry and electroplating technology and for Motailkorrosionsvorbeugung.

Characteristic of the known state of the art

Is a process for the production of sodium gluconate by microbiological means known inter alia from the following publications:

- R. Mlom. V. Pfeifer, A. Mover. D.Tranfler u. M.Conway - "Industrial and Engineering Chemistry", 1952 V.44 No. 2,435-440.

- H. Peppier u. D. Periman - "Microbial Technology", V. 1.376-383, New York, 1979. M. Roehr, C. Kubicek, J. Kominek "Biotechnology", V.3.456-465. Weinheim. 1,983th

The method is based on the use of the fermentation substrate water solution of pure glucose with the addition of manganese salt, potassium, magnesium and ammonium salts in the form of sulfates and phosphates and with the addition of natural components such as yeast extract, peptones or macerated maize. The already sterilized substrate is inoculated with spores of Aspergilius niger, and at the temperature of 30 ⁰ C strongly aerated to ensure the growth of mycelium, and the. Bioconversion of the glucose to gluconic acid. During fermentation, the resulting gluconic acid is gradually neutralized by sodium hydroxide. After completion of the fermentation process, the entire mass is filtered to separate the mycelium. From the filtrate, which is compressed, then sodium gluconate is separated by crystallization or drying in appropriate facilities.

Similar methods are described in Amurican patent specifications Nos. 3576718 and 3907640 and in the patent specification of FRG No. 1817907, in which in addition to pure glucose and inorganic salts also natural additives are used in the fermentation substrate, such as: peptone, potato extract, macerated corn or urea. The disadvantage of the known solutions is that expensive pure glucose is used in these methods, which increases the cost of the guarantor of sodium gluconate, these costs are still increased by the cost of the natural components used.

Object of the invention

The invention provides a process for the preparation of sodium gluconate which is more economical than previously known processes by using cheaper raw materials and improved technology.

Explanation of the invention

The object of the present invention is to develop a process for the production of sodium gluconate.

According to the invention, this object is achieved by a method in which; for the preparation of the fermentation substrate in addition to inorganic components starch hydrolyzate with 5-80 DE, preferably 10-45, is used, which contains glucose, maltose and oligosaccharides. After sterilization of the substrate and before inoculation with spores of Aspergillus niger, at temperatures of 70-30 ⁰ C, 0.01-0.04% is added in proportion to the total mass enzyme preparation with glucoamylase.

This is followed by saccharification and bioconversion as well as stepwise neutralization by sodium hydroxide.

The importance of the process according to the invention is to use, instead of the expensive glucose, a cheaper raw material such as starch hydrolyzate, which is obtained from the starch after the acid, acid-enzyme or enzyme hydrolysis and which mainly contains glucose, maltose and oligosaccharides. The high efficiency of the process using the starch hydrolysates was achieved thanks to the appropriately selected technological parameters and the combination of the saccharification process of the substrate and the bioconversion process.

Both processes are carried out simultaneously in the bioreactor. It has also been found that the final product obtained is chemically pure and does not differ in its properties from the product of the bioconversion of pure glucose.

Ausführungsbeisplelo

Dio following examples explain in more detail clio invention.

example 1

In 700-90Og of water is dissolved 200g starch hydrolyzate from the acid hydrolysis with DE = 45.0, 0.4 g (NH ₄ I ₂ HPO ₄ , 0.2 g MgSO ₄ .7H ₂ O, 0.3 g KH ₂ PO _4. The Müs wirl sterilized and cooled to dio temperature of 60'C, then is added with glucoamylase in relation to the substrate ground 0.01-0.04% enzyme preparation This substrate is NaCl ,, .bkühlung to the temperature of 30 ° C with germs -.. spores of Aspergillus niger 10 ° relative to its mass, inoculated.

In the seeded substrate, bioconversion is carried out at the same time as its saccharification at the temperature of 30 ° C and with intensive aeration in the time of 36 hours. The gluconic acid formed during the process is gradually neutralized with 25 percent solution of NaOH, maintaining the pH of the substrate at 5-7 bd. After 36 hours of bioconversion, the 98piozentigo oxidation of glucose to gluconic acid and the corresponding stoichiometric amount of sodium gluconate are achieved.

Claims (1)

1. A process for the preparation of sodium gluconate by microbiological means, by bioconversion of the fermentation substrate with (NH ₄ ^ HPO ₄ , MgSO ₄ · 7H ^ O · KH ₂ PO ₄ , which is first sterilized and then inoculated with spores of Aspergillus niger and by stepwise Neutralization of the resulting gluconic acid with NaOH during bioconversion characterized in that, in addition to inorganic components, starch hydrolyzate containing 5-80 DE, preferably 10-45, containing glucose, maltose and oligosaccharides is used to prepare the fermentation substrate, and that after sterilization of the substrate , at a temperature of 70-30 ⁰ C, 0.01-0.04% enzyme preparation with Glucoamylasa added in relation to the total mass, and that the mass is inoculated with spores of Aspergillus niger and then simultaneously the saccharification and the bioconversion and the stepwise neutralization is carried out. Field of application in the invention