апрель 2019

Protelotic microbial enzymal preparations and prospects for their practical application

D. S. Rytik , T. P. Kilochok
Химия и современные технологии
Abstract / Full Text

Enzymes possessing the ability to hydrolyze proteins are widely used in a wide variety of industries, agriculture and medicine.

Protease (Proteases) has been registered as a food additive with the international code E1104. The official list of nutritional supplements specifies 4 types of proteolytic enzymes that are included in the dietary supplements: protease, papain, bromelain, ficin.

Several studies have shown that proteolytic enzymes can be used in bread making to reduce the duration of cooked bread production and special products made from flour with strong gluten.

Getting microbial proteases is an important part of the industrial sector, as demand for these preparations increases every year. [1]

The proteolytic enzymes are divided, depending on the place of action on the exoeptidase, which can break the final bonds, and the endopeptidases, which carry out the hydrolysis of the internal bonds in the protein molecule. Endopeptidases, depending on the structure of the active element, are divided into:

− serine, in the part of their active center there is serine and histidine residue;

− cysteine, in their active center there is a SH-group from the cysteine residue;

− carboxyl, in their active center there is a COOH group from the residue of asparaginate − metalloproteinase, in the active center there is a metal ion.

The selectivity of protease activity is influenced by the amino acid structure of the residues, their radicals, and the spatial configuration of the substrate.

Most proteases react to a certain structure of the amino acid residues located near the bond that is being broken down.

In the microbiological industry, producers of neutral and alkaline proteinases are used. Neutralinase proteases are synthesized by a number of bacterial cultures: Bacillus megaterium, Bac. brevis bac cerius, Pseudomonus fragiae and others. Various strains of B. stearothermophilus synthesize thermostable proteinases.

A significant spectrum of proteinases with a different substrate specificity, acting in a wide range of pHs, has been detected in actinomycetes and streptomycetes (Actinomyces fradiae, Streptomyces recifensis var. Lyticus, etc.).

Streptomyces recifensis var.lyticus, is a highly effective and non-pathogenic biological agent for the production of proteolytic enzymes. However, the use of this strain is possible only with constant selective work and optimization of the medium to enhance its biosynthetic ability.

Enzymes retain their unique properties (efficiency, specificity) outside cells, so they can be used as catalysts in various chemical processes and medicine.

Such biological catalysts are non-toxic, operate in mild conditions, use available raw materials (including waste), in connection with which their application in industry is beneficial from the economic and environmental point of view. When using enzymes instead of cells, bioreactors do not require aeration system and it is much easier to maintain the temperature regime. Instead of a complex composition of a culture fluid containing the nutrient medium, cells and products of their metabolism, the process proceeds virtually in the aqueous solution of the transformed substance, which greatly simplifies and reduces the cost of separation and purification of the target product.

Preparations of proteolytic enzymes of various degree of purification are obtained by surface and deep cultivation in optimizing the conditions of cultivation: physical and chemical factors and optimization of quantitative and qualitative composition of seed and fermentation media. [2]

Examples of such enzymes are Protorysin P20x, Protorrhizin P10x, Protosubtilin G10h. These are preparations obtained by superficial cultivation of fungi of the genus Aspergillus. Preparations Protosubtilin G3x, Protosubtilin G10h are obtained by deep cultivation of rodent bacteria − Basillus subtilis 103.

Every year the demand for proteolytic microbial enzymes increases and there is a growing need for their production. Therefore, it is important to optimize the technology of production of proteolytic enzymes of various degree of purification and to seek their application in new industries.

  1. I. M. Gracheva, Technology of enzyme preparations. − 3rd ed., Pererab. and add [Text] / I.M. Gracheva, A.Yu. Krivova − M.: "Elevar", 2000 − 512s.
  2. E. V. Lukasheva, Prospects for using enzymes in maternal therapy. Congress "Biotechnology: the state and prospects" [Text] // E.V. Lukasheva, E. M. Treshalina, T. T. Berezov − M.: Mir, 2005. − 166 p.