Propionic acid bacteria, the properties of which will be discussed below, are united by the genus Propionibacterium. It, in turn, belongs to the Propionibacteriaceae family. Let us consider in more detail what characteristics propionic acid bacteria have, where these microorganisms are kept and used.
Description
Propoic acid bacteria are catalase-positive, Gram-positive, non-motile, non-spore-forming aerotolerant microorganisms or facultative anaerobes. The optimum temperature for their growth is 30-37 degrees. They form brown, red, orange, cream or yellow colonies. Bacterial cells are club-shaped. One end is narrowed, the other is rounded. The shape of some cells may resemble a cocoon, be branched or forked. Elements are located singly, in pairs, as well as in short chains. Propionic acid bacteria contain a C15-saturated fatty acid of membrane lipids, menaquinones. During fermentation, they form a specific substance. It ispropionic acid. She, in fact, gave the name to these microorganisms. The genus Propionibacterium includes three groups of bacteria: Propionibacterium propionicus, dermal and classic.
Characteristics
The classical type includes propionic acid bacteria of cheese and milk. They include 4 species: P. Acidipropionici, P. Jensenii, P. Thoenii and P. Freudenreichii. Skin propionic acid bacteria live, respectively, on the skin of people, in the rumen of various ruminants. They are considered as biological protection and useful microflora. Propionic acid bacteria of this type provide increased immunostimulating reactions, have a beneficial effect on farm birds and animals. In this regard, they are used as components of prophylactic and therapeutic agents. Skin bacteria live not only on he althy surfaces. They are found in acne, less often in the contents of the stomach, soft and purulent tissue abscesses, blood, wounds. However, their involvement in the occurrence of diseases has not been reliably established. The third group of bacteria includes only Propionibacterium propionicus. They live in the soil.
Synthetic abilities
They are sufficiently developed in propionic acid bacteria, but differ depending on the species and strain. It has now been established that some bacteria have the ability to fix molecular nitrogen, synthesize vitamins on their own (in particular, B12), and use hydrocarbons. During fermentation, they release biomass,which is widely used in practice. In addition, the product of their activity is acetic and propionic acids.
Enzymatically Inactive Biomass Applications
Synthesis product used:
- In animal husbandry. Inactive biomass acts as a protein of a unicellular organism. Of particular importance are sulfur-containing amino acids, especially methionine, threonine and lysine, B-group vitamins, trace elements. They are found in large quantities in the biomass produced by propionic acid bacteria.
- Preparations created from heat-killed skin microorganisms have immunostimulatory, antibacterial, antiviral effects. In addition, studies have found that P. acnes have the ability to slow down the growth of various types of tumors, including malignant ones.
- Killed P. granulosum act as a source of porphyrins. Along with metal complexes, they are used as pigments and dyes, including in the food industry, as catalysts for redox reactions, oxidation of mercaptans in oil and oil products, hydrocarbons, etc. In addition, P. granulosum can be used to create therapeutic and diagnostic preparations.
Active Biomass
Currently, products that secrete propionic acid bacteria are used in a variety of areas. Sourdough, in particular, is one of the most common ingredients in the food industry. For example, it is used inbakeries. Along with lactic acid bacteria and yeast, propionic acid microorganisms are included in some starter cultures. They provide an increase in the shelf life of bread. This is achieved due to the inhibitory effect of propionic acid on the development of mold fungi. In addition, the product is enriched with vitamin B12. This fact is of particular importance for dieters and vegetarians. Starter cultures are also used for ensiling fodder. Active biomass is used in the production of B12. Creating a vitamin by chemical synthesis is impossible in practice. For this, propionic acid bacteria are used.
Agricultural applications
During the storage of the crop, pests can destroy up to 15% of its total volume. When the humidity exceeds 14%, the grain heats up and begins to become moldy. Storage methods that involve drying, keeping at low temperatures or in sealed containers are quite difficult to implement in practice. To solve these problems, in some countries spraying the grain with a weakly concentrated solution of propionic acid is carried out. It reduces the active growth of seeds, neutralizes microorganisms, and primarily mold fungi.
Propionic acid bacteria: "Evita"
In the mid-90s of the last century, a group of domestic microbiologists created a unique product. It has an exceptionally high therapeutic and prophylactic effect and biological value. The product was named "Evita". When itcow's milk is used in the production. The production is based on the fermentation method using a special starter, presented as a stable symbiosis of bacterial cultures, among which propionic acid bacteria play the leading role.
Mechanism of action
Propionic acid bacteria are considered beneficial to the body. Being in the intestines, they restore proteins after stress, exposure to chemical compounds, ultraviolet radiation. Bacteria prevent the formation of substances that contribute to the development of oncology. In their presence, the intestinal environment is modified in the direction of decreasing pH. Bacteria exhibit an antagonistic effect on pathogenic and conditionally pathogenic microorganisms, stimulate the development of lacto- and bifidobacteria. It has been established that they have high resistance to antibiotics, especially the penicillin group, as well as sulfonamides and increased acidity of the gastric environment. All these unique properties of strains of propionic acid bacteria formed the basis of the mechanism of action of the Evita product. Moreover, it is considered the only remedy in which B12 is present in a therapeutic dose. This vitamin is involved in hematopoiesis, activation of blood clotting. It is indicated for malignant anemia, atherosclerosis, alcoholism, dystrophy, cerebral palsy, Down syndrome, anemia (iron deficiency), multiple sclerosis, psoriasis, stomach polyposis.
Effect on casein (milk protein)
This element is rather poorly absorbed by an adult organism due to the lack of compounds that break it down. When fermenting milk using the product "Evita", there is a complete breakdown of the protein into amino acids. They create a nutrient medium for beneficial intestinal microflora. In the process of fermentation, a lot of volatile fatty acids are also formed. Among them are acetic, propionic, oily, folic, isovaleric, formic and others. These acids act as the main source of nutrition for the intestinal epithelium. They also contribute to the conversion of primary bile acids into secondary ones and their reabsorption. This effect is used in the treatment of diarrheal syndrome with Evita in patients suffering from pathologies of the small intestine and liver.
Extra
It should be noted that the bacterial symbiosis selected by scientists is distinguished by the high resistance of the finished product to the action of phenol. This, in turn, indicates the preservation of its medicinal qualities in the gastrointestinal tract. In the Research Institute of Hygienic Regulation and Toxicology, Serpukhov, the antimutagenic properties of the product were also proven. The key feature of the product is its ability to quickly restore the microflora. It, in turn, ensures the mobilization of the body to fight a sufficiently large number of diseases.
