Industrial use of microorganisms. The use of microorganisms in medicine, agriculture; benefits of probiotics

Practical use of bacteria in food production

Among bacteria, lactic acid bacteria of the genera Lactobacillus, Streptococcus in the production of dairy products. Cocci have a round, oval shape with a diameter of 0.5-1.5 microns, arranged in pairs or chains of different lengths. The sizes of rod-shaped bacteria or combined into chains.

Lactic acid streptococcus Streptococcus lactis has cells connected in pairs or short chains, coagulates milk after 10-12 hours, some races form the antibiotic nisin.

C 6 H 12 O 6 → 2CH 3 CHOHCOOH

Creamy Streptococcus S. cremoris forms long chains from spherical cells, an inactive acid-forming agent, is used in the fermentation of cream in the production of sour cream.

acidophilus bacillus lactobacillus acidophilus form long chains of rod-shaped cells; during fermentation, it accumulates up to 2.2% lactic acid and antibiotic substances that are active against pathogens of intestinal diseases. Based on them, medical biological preparations are prepared for the prevention and treatment of gastrointestinal diseases in farm animals.

Lactic acid sticks L. plantatum have cells linked in pairs or in chains. Causative agents of fermentation during fermentation of vegetables and silage of fodder. L. brevis ferment sugars during sauerkraut, cucumbers, forming acids, ethanol, CO 2.

Non-sporing, non-motile, gram+ rods of the genus Propionibacterium families Propionibacteriaceae- causative agents of propionic acid fermentation, cause the conversion of sugar or lactic acid and its salts into propionic and acetic acid.

3C 6 H 12 O 6 → 4CH 3 CH 2 COOH + 2CH 3 COOH + 2CO 2 + 2H 2 O

Propionic acid fermentation underlies the maturation of rennet cheeses. Some types of propionic acid bacteria are used to produce vitamin B 12 .

spore-forming bacteria of the family Bacilloceae kind Clostridium are causative agents of butyric fermentation, converting sugars into butyric acid

C 6 H 12 O 6 → CH 3 (CH 2) COOH + 2CO 2 + 2H 2

Butyric acid

habitats- soil, silt deposits of reservoirs, accumulations of decaying organic residues, food products.

These m / o are used in the production of butyric acid, which has an unpleasant odor, in contrast to its esters:

Methyl ether - apple smell;

Ethyl - pear;

Amyl - pineapple.

They are used as flavorings.

Butyric acid bacteria can cause spoilage of food raw materials and products: swelling of cheeses, rancidity of milk, butter, bombing of canned food, death of potatoes and vegetables. The resulting butyric acid gives a sharp rancid taste, a sharp unpleasant odor.

Acetic acid bacteria - non-sporing Gram-rods with polar flagella, belong to the genus Gluconobacter (Acetomonas); form acetic acid from ethanol

CH 3 CH 2 OH+O 2 →CH 3 COOH+H 2 O

Rods of the Kind Acetobacter- peritrichous, capable of oxidizing acetic acid to CO 2 and H 2 O.

Acetic acid bacteria are characterized by variability in shape; under unfavorable conditions, they take the form of thick long filaments, sometimes swollen. Acetic acid bacteria are widely distributed on the surface of plants, their fruits, and in pickled vegetables.

The process of oxidizing ethanol to acetic acid underlies the production of vinegar. Spontaneous development of acetic acid bacteria in wine, beer, kvass leads to their deterioration - souring, turbidity. These bacteria on the surface of liquids form dry wrinkled films, islands or a ring near the walls of the vessel.

Common type of damage putrefaction is the process of deep decomposition of protein substances by microorganisms. The most active causative agents of putrefactive processes are bacteria.

Hay and potato stickBacillus subtilis - aerobic gram + spore-forming bacillus. Spores heat-resistant oval. Cells are sensitive to acidic environment and elevated NaCl content.

Bacteria of the genusPseudomonus - aerobic motile rods with polar flagella, do not form spores, gram-. Some species synthesize pigments, they are called fluorescent pseudomonas, there are cold-resistant ones, they cause spoilage of protein products in refrigerators. Causative agents of bacterioses of cultivated plants.

Spore-forming rods of the genus Clostridium decompose proteins with the formation of a large amount of gas NH 3, H 2 S, acids, especially dangerous for canned food. Severe food poisoning is caused by the toxin of large mobile gram+ sticks. Clostridium botulinum. Spores give the appearance of a racket. The exotoxin of these bacteria affects the central nervous and cardiovascular systems (signs - visual impairment, speech, paralysis, respiratory failure).

Nitrifying, denitrifying, and nitrogen-fixing bacteria are of great importance in soil formation. Basically, these are non-spore-forming cells. They are grown in artificial conditions and applied in the form of fertilizer preparations.

Bacteria are used in the production of hydrolytic enzymes, amino acids for food production.

Among bacteria, it is especially necessary to highlight the causative agents of food infections and food poisoning.. Food infections are caused by pathogenic bacteria present in food and water. Intestinal infections - cholera - cholera virion;

Bacteria is the most ancient organism on earth, as well as the simplest in its structure. It consists of only one cell, which can only be seen and studied under a microscope. A characteristic feature of bacteria is the absence of a nucleus, which is why bacteria are classified as prokaryotes.

Some species form small groups of cells; such clusters may be surrounded by a capsule (sheath). The size, shape, and color of bacteria are highly dependent on the environment.

In terms of shape, bacteria are divided into: rod-shaped (bacilli), spherical (cocci) and convoluted (spirilla). There are also modified ones - cubic, C-shaped, star-shaped. Their sizes range from 1 to 10 microns. Certain types of bacteria can actively move with the help of flagella. The latter sometimes exceed the size of the bacterium itself twice.

Types of bacteria forms

For movement, bacteria use flagella, the number of which is different - one, a pair, a bundle of flagella. The location of the flagella is also different - on one side of the cell, on the sides, or evenly distributed over the entire plane. Also, one of the ways of movement is considered to be sliding due to the mucus that the prokaryote is covered with. Most have vacuoles inside the cytoplasm. Adjusting the capacity of the gas in the vacuoles helps them move up or down in the liquid, as well as move through the air channels of the soil.

Scientists have discovered more than 10 thousand varieties of bacteria, but according to the assumptions of scientific researchers, there are more than a million species of them in the world. The general characteristics of bacteria makes it possible to determine their role in the biosphere, as well as to study the structure, types and classification of the bacterial kingdom.

habitats

The simplicity of the structure and the speed of adaptation to environmental conditions helped bacteria to spread over a wide range of our planet. They exist everywhere: water, soil, air, living organisms - all this is the most acceptable habitat for prokaryotes.

Bacteria have been found both at the south pole and in geysers. They are on the ocean floor, as well as in the upper layers of the Earth's air shell. Bacteria live everywhere, but their number depends on favorable conditions. For example, a large number of bacterial species live in open water bodies, as well as in the soil.

Structural features

A bacterial cell is distinguished not only by the fact that it does not have a nucleus, but also by the absence of mitochondria and plastids. The DNA of this prokaryote is located in a special nuclear zone and has the form of a nucleoid closed in a ring. In bacteria, the cell structure consists of a cell wall, a capsule, a capsule-like membrane, flagella, pili, and a cytoplasmic membrane. The internal structure is formed by the cytoplasm, granules, mesosomes, ribosomes, plasmids, inclusions and nucleoid.

The bacterial cell wall performs the function of defense and support. Substances can freely flow through it due to permeability. This shell contains pectin and hemicellulose. Some bacteria secrete a special mucus that can help protect against drying out. Mucus forms a capsule - a polysaccharide in chemical composition. In this form, the bacterium is able to tolerate even very high temperatures. It also performs other functions, for example, sticking to any surfaces.

On the surface of the bacterial cell are thin protein villi - pili. There may be a large number of them. Pili help the cell to transfer genetic material, and also provide adhesion to other cells.

Under the plane of the wall is a three-layer cytoplasmic membrane. It guarantees the transport of substances, and also plays a significant role in the formation of spores.

The cytoplasm of bacteria is 75 percent made from water. The composition of the cytoplasm:

fishsomes;
mesosomes;
amino acids;
enzymes;
pigments;
sugar;
granules and inclusions;
nucleoid.

Metabolism in prokaryotes is possible, both with the participation of oxygen and without it. Most of them feed on ready-made nutrients of organic origin. Very few species are capable of synthesizing organic substances from inorganic ones themselves. These are blue-green bacteria and cyanobacteria, which played a significant role in shaping the atmosphere and saturating it with oxygen.

reproduction

In conditions favorable for reproduction, it is carried out by budding or vegetatively. Asexual reproduction occurs in the following sequence:

The bacterial cell reaches its maximum volume and contains the necessary supply of nutrients.
The cell lengthens, a partition appears in the middle.
Within the cell, a division of the nucleotide occurs.
DNA main and separated diverge.
The cell is divided in half.
Residual formation of daughter cells.

With this method of reproduction, there is no exchange of genetic information, so all daughter cells will be an exact copy of the mother.

The process of reproduction of bacteria in adverse conditions is more interesting. Scientists learned about the ability of bacteria to reproduce sexually relatively recently - in 1946. Bacteria do not have a division into female and germ cells. But they have different DNA. Two such cells, when approaching each other, form a channel for the transfer of DNA, an exchange of sites occurs - recombination. The process is quite long, the result of which are two completely new individuals.

Most bacteria are very difficult to see under a microscope because they do not have their own color. Few varieties are purple or green due to their content of bacteriochlorophyll and bacteriopurpurine. Although if we consider some colonies of bacteria, it becomes clear that they release colored substances into the environment and acquire a bright color. In order to study prokaryotes in more detail, they are stained.

Classification

The classification of bacteria can be based on indicators such as:

The form
way to travel;
way to get energy;
waste products;
degree of danger.

Bacteria symbionts live in partnership with other organisms.

Bacteria saprophytes live on already dead organisms, products and organic waste. They contribute to the processes of decay and fermentation.

Decay cleanses nature of corpses and other wastes of organic origin. Without the process of decay, there would be no cycle of substances in nature. So what is the role of bacteria in the cycling of matter?

Decay bacteria are an assistant in the process of breaking down protein compounds, as well as fats and other compounds containing nitrogen. Having carried out a complex chemical reaction, they break bonds between the molecules of organic organisms and capture protein molecules, amino acids. Splitting, the molecules release ammonia, hydrogen sulfide and other harmful substances. They are poisonous and can cause poisoning in humans and animals.

Decay bacteria multiply rapidly in favorable conditions for them. Since these are not only beneficial bacteria, but also harmful ones, in order to prevent premature decay in products, people have learned to process them: dry, pickle, salt, smoke. All of these treatments kill bacteria and prevent them from multiplying.

Fermentation bacteria with the help of enzymes are able to break down carbohydrates. People noticed this ability in ancient times and use such bacteria to make lactic acid products, vinegars, and other food products to this day.

Bacteria, working in conjunction with other organisms, do very important chemical work. It is very important to know what types of bacteria are and what benefits or harm they bring to nature.

Significance in nature and for man

The great importance of many types of bacteria (in the processes of putrefaction and various types of fermentation) has already been noted above; fulfillment of a sanitary role on Earth.

Bacteria also play a huge role in the cycle of carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur, calcium and other elements. Many types of bacteria contribute to the active fixation of atmospheric nitrogen and convert it into an organic form, contributing to an increase in soil fertility. Of particular importance are those bacteria that decompose cellulose, which are the main source of carbon for the vital activity of soil microorganisms.

Sulfate-reducing bacteria are involved in the formation of oil and hydrogen sulfide in therapeutic mud, soils and seas. Thus, the layer of water saturated with hydrogen sulfide in the Black Sea is the result of the vital activity of sulfate-reducing bacteria. The activity of these bacteria in soils leads to the formation of soda and soda salinization of the soil. Sulfate-reducing bacteria convert nutrients in rice plantation soils into a form that becomes available to the roots of the crop. These bacteria can cause corrosion of metal underground and underwater structures.

Thanks to the vital activity of bacteria, the soil is freed from many products and harmful organisms and saturated with valuable nutrients. Bactericidal preparations are successfully used to combat many types of insect pests (corn borer, etc.).

Many types of bacteria are used in various industries to produce acetone, ethyl and butyl alcohols, acetic acid, enzymes, hormones, vitamins, antibiotics, protein and vitamin preparations, etc.

Without bacteria, processes are impossible in tanning leather, drying tobacco leaves, making silk, rubber, processing cocoa, coffee, urinating hemp, flax and other bast-fiber plants, sauerkraut, sewage treatment, leaching metals, etc.

Modern biotechnology is based on many sciences: genetics, microbiology, biochemistry, natural science. The main object of their study are bacteria and microorganisms. It is the use of bacteria that solves many problems in biotechnology. Today, the scope of their use in human life is so wide and varied that it makes an invaluable contribution to the development of such industries as:

medicine and health care;
animal husbandry;
crop production;
fish industry;
food industry;
mining and energy;
heavy and light industry;
septic tank;
ecology.

Health care and pharmacology

The field of application of bacteria in pharmacology and medicine is so wide and significant that their role in the treatment of many diseases in humans is simply invaluable. In our life, they are necessary when creating blood substitutes, antibiotics, amino acids, enzymes, antiviral and anticancer drugs, DNA samples for diagnostics, hormonal drugs.

Scientists have made an invaluable contribution to medicine by identifying the gene responsible for the hormone insulin. By implanting it into the coli bacteria, they got the production of insulin, saving the lives of many patients. Japanese scientists have discovered bacteria that secrete a substance that destroys plaque, thereby preventing the appearance of caries in humans.

From thermophilic bacteria, a gene is derived that encodes enzymes that are of value in scientific research, since they are insensitive to high temperatures. In the production of vitamins in medicine, the microorganism Clostridium is used, while obtaining riboflavin, which plays an important role in human health.

The ability of bacteria to produce antibacterial substances was used to create antibiotics, solving the problem of treating many infectious diseases, thereby saving the life of more than one person.

Extraction and processing of minerals

The use of biotechnologies in the extractive industry can significantly reduce costs and energy costs. Thus, the use of lithotrophic bacteria (Thiobacillus ferrooxidous), with their ability to oxidize iron, is used in hydrometallurgy. Due to bacterial leaching, precious metals are mined from low-bearing rocks. Methane-containing bacteria are used to increase oil production. When oil is extracted in the usual way, no more than half of the natural reserves are extracted from the bowels, and with the help of microorganisms, more efficient release of reserves occurs.

Light and heavy industry

Microbiological leaching is used in old mines to produce zinc, nickel, copper, cobalt. In the mining industry, bacterial sulfates are used for reduction reactions in old mines, since sulfuric acid residues have a destructive effect on supports, materials and the environment. Anaerobic microorganisms contribute to the thorough decomposition of organic matter. This property is used for water purification in the metallurgical industry.

A person uses bacteria in the production of wool, artificial leather, textile raw materials, for perfumery and cosmetic purposes.

Waste and water treatment

The bacteria involved in decomposition are used to clean septic tanks. The basis of this method is that microorganisms feed on sewage. This method ensures the removal of odor and disinfection of wastewater. Microorganisms used in septic tanks are grown in laboratories. The result of their action is determined by the breakdown of organic matter into simple substances that are harmless to the environment. Depending on the type of septic tank, anaerobic or aerobic microorganisms are selected. Aerobic microorganisms, in addition to septic tanks, are used in biofilters.

Microorganisms are also needed to maintain the quality of water in reservoirs and drains, to clean the polluted surface of the seas and oceans from oil products.

With the development of biotechnology in our lives, humanity has stepped forward in almost all areas of its activity.

Bacteria are single-celled non-nuclear microorganisms belonging to the class of prokaryotes. To date, there are more than 10 thousand studied species (it is assumed that there are about a million of them), many of them are pathogenic and can cause various diseases in humans, animals and plants.

For their reproduction, a sufficient amount of oxygen and optimal humidity are necessary. The sizes of bacteria vary from tenths of a micron to several microns, in shape they are divided into spherical (cocci), rod-shaped, filamentous (spirilla), in the form of curved rods (vibrios).

The first organisms that appeared billions of years ago

(Bacteria and microbes under the microscope)

Bacteria play a very important role on our planet, being an important participant in any biological cycle of substances, the basis for the existence of all life on Earth. Most of both organic and inorganic compounds change significantly under the influence of bacteria. Bacteria, which appeared on our planet more than 3.5 billion years ago, stood at the primary sources of the base of the living shell of the planet and still actively process inanimate and living organic matter and involve the results of the metabolic process in the biological cycle.

(The structure of a bacterium)

Saprophytic soil bacteria play a huge role in the soil-forming process, it is they who process the remains of plant and animal organisms and help in the formation of humus and humus, which increase its fertility. The most important role in the process of improving soil fertility is played by nitrogen-fixing nodule symbiont bacteria that “live” on the roots of leguminous plants; thanks to them, the soil is enriched with valuable nitrogen compounds necessary for plant growth. They capture nitrogen from the air, bind it and create compounds in a form available to plants.

The importance of bacteria in the cycle of substances in nature

Bacteria have excellent sanitary qualities, they remove dirt in wastewater, break down organic matter, turning them into harmless inorganics. The unique cyanobacteria that originated in the primordial seas and oceans 2 billion years ago were capable of photosynthesis, they supplied molecular oxygen to the environment, and thus formed the Earth's atmosphere and created an ozone layer that protects our planet from the harmful effects of ultraviolet rays. Many minerals have been created over many thousands of years by the action of air, temperature, water and bacteria on biomass.

Bacteria are the most common organisms on Earth, they define the upper and lower boundaries of the biosphere, penetrate everywhere and are distinguished by great endurance. If there were no bacteria, dead animals and plants would not be processed further, but simply accumulated in huge quantities, without them the biological cycle would become impossible, and substances would not be able to return to nature again.

Bacteria are an important link in the trophic food chains, they act as decomposers, laying out the remains of dead animals and plants, thereby cleansing the Earth. Many bacteria play the role of symbionts in the body of mammals and help them decompose fiber, which they are not able to digest. The life process of bacteria is a source of vitamin K and B vitamins, which play an important role in the normal functioning of their organisms.

Beneficial and harmful bacteria

A large number of pathogenic bacteria can bring great harm to human health, domestic animals and cultivated plants, namely, to cause such infectious diseases as dysentery, tuberculosis, cholera, bronchitis, brucellosis and anthrax (animals), bacteriosis (plants).

There are bacteria that bring benefits to a person and his economic activity. People have learned to use bacteria in industrial production, making acetone, ethyl and butyl alcohol, acetic acid, enzymes, hormones, vitamins, antibiotics, protein and vitamin preparations. The cleansing power of bacteria is used in water treatment plants, to treat wastewater and to convert organics into harmless inorganic substances. Modern achievements of genetic engineers have made it possible to obtain such drugs as insulin, interferon from the bacteria of Escherichia coli, feed and food protein from some bacteria. In agriculture, special bacterial fertilizers are used, and with the help of bacteria, farmers fight various weeds and harmful insects.

(Bacteria favorite dish ciliates slippers)

Bacteria are involved in the process of tanning leather, drying tobacco leaves, they are used to make silk, rubber, cocoa, coffee, soak hemp, linen, and leach metals. They are involved in the manufacturing process of drugs, such powerful antibiotics as tetracycline and streptomycin. Without lactic acid bacteria that cause the fermentation process, the process of preparing such dairy products as yogurt, fermented baked milk, acidophilus, sour cream, butter, kefir, yogurt, and cottage cheese is impossible. Also, lactic acid bacteria are involved in the process of pickling cucumbers, sauerkraut, ensiling feed.

Microbiological processes are widely used in various sectors of the national economy. Many processes are based on metabolic reactions that occur during the growth and reproduction of certain microorganisms.

With the help of microorganisms, feed proteins, enzymes, vitamins, amino acids, organic acids, etc. are produced.

The main groups of microorganisms used in the food industry are bacteria, yeasts and molds.

bacteria. Used as causative agents of lactic acid, acetic acid, butyric, acetone-butyl fermentation.

Cultural lactic acid bacteria are used in the production of lactic acid, in baking, and sometimes in alcohol production. They convert sugar into lactic acid according to the equation

C6H12O6 ® 2CH3 – CH – COOH + 75 kJ

True (homofermentative) and non-true (heterofermentative) lactic acid bacteria are involved in the production of rye bread. Homofermentative ones are involved only in acid formation, while heterofermentative ones, along with lactic acid, form volatile acids (mainly acetic), alcohol and carbon dioxide.

In the alcohol industry, lactic acid fermentation is used to acidify yeast wort. Wild lactic acid bacteria adversely affect the technological processes of fermentation plants, worsen the quality of finished products. The resulting lactic acid inhibits the vital activity of extraneous microorganisms.

Butyric fermentation, caused by butyric bacteria, is used to produce butyric acid, the esters of which are used as aromatics.

Butyric acid bacteria convert sugar into butyric acid according to the equation

C6H12O6 ® CH3CH2CH2COOH + 2CO2 + H2 + Q

Acetic acid bacteria are used to produce vinegar (acetic acid solution), because. they are able to oxidize ethyl alcohol to acetic acid according to the equation

C2H5OH + O2 ® CH3COOH + H2O +487 kJ

Acetic acid fermentation is harmful to alcohol production, because. leads to a decrease in the yield of alcohol, and in brewing it causes spoilage of beer.

Yeast. They are used as fermentation agents in the production of alcohol and beer, in winemaking, in the production of bread kvass, in baking.

For food production, yeast is important - saccharomycetes, which form spores, and imperfect yeast - non-saccharomycetes (yeast-like fungi), which do not form spores. The Saccharomyces family is divided into several genera. The most important is the genus Saccharomyces (saccharomycetes). The genus is subdivided into species, and individual varieties of a species are called races. In each industry, separate races of yeast are used. Distinguish yeast pulverized and flaky. In dust-like cells, they are isolated from each other, while in flaky cells, they stick together, forming flakes, and quickly settle.

Cultural yeast belongs to the S. cerevisiae family of Saccharomycetes. The temperature optimum for yeast propagation is 25-30 0С, and the minimum temperature is about 2-3 0С. At 40 0C, growth stops, yeast dies, and at low temperatures, reproduction stops.

There are top and bottom fermenting yeasts.

Of the cultural yeasts, bottom-fermenting yeasts include most wine and beer yeasts, and top-fermenting yeasts include alcohol, baker's and some races of brewer's yeast.

As is known, in the process of alcoholic fermentation from glucose, two main products are formed - ethanol and carbon dioxide, as well as intermediate secondary products: glycerol, succinic, acetic and pyruvic acids, acetaldehyde, 2,3-butylene glycol, acetoin, esters and fusel oils (isoamyl , isopropyl, butyl and other alcohols).

Fermentation of individual sugars occurs in a certain sequence, due to the rate of their diffusion into the yeast cell. Glucose and fructose are the fastest fermented by yeast. Sucrose, as such, disappears (inverts) in the medium at the beginning of fermentation under the action of the yeast enzyme b - fructofuranosidase, with the formation of glucose and fructose, which are easily used by the cell. When there is no glucose and fructose left in the medium, the yeast consumes maltose.

Yeast has the ability to ferment very high concentrations of sugar - up to 60%, they also tolerate high concentrations of alcohol - up to 14-16 vol. %.

In the presence of oxygen, alcoholic fermentation stops and the yeast obtains energy from oxygen respiration:

C6H12O6 + 6O2 ® 6CO2 + 6H2O + 2824 kJ

Since the process is more energetically rich than the fermentation process (118 kJ), the yeast spends sugar much more economically. The termination of fermentation under the influence of atmospheric oxygen is called the Pasteur effect.

In alcohol production, top yeast of the species S. cerevisiae is used, which have the highest fermentation energy, form a maximum of alcohol and ferment mono- and disaccharides, as well as part of dextrins.

In baker's yeast, fast-growing races with good lifting power and storage stability are valued.

In brewing, bottom-fermenting yeast is used, adapted to relatively low temperatures. They must be microbiologically clean, have the ability to flocculate, quickly settle to the bottom of the fermenter. Fermentation temperature 6-8 0C.

In winemaking, yeasts are valued, which multiply rapidly, have the ability to suppress other types of yeast and microorganisms and give the wine an appropriate bouquet. The yeasts used in winemaking are S. vini and ferment glucose, fructose, sucrose and maltose vigorously. In winemaking, almost all production yeast cultures are isolated from young wines in various areas.

Zygomycetes- mold fungi, they play an important role as enzyme producers. Fungi of the genus Aspergillus produce amylolytic, pectolytic and other enzymes, which are used in the alcohol industry instead of malt for starch saccharification, in brewing when malt is partially replaced by unmalted raw materials, etc.

In the production of citric acid, A. niger is the causative agent of citrate fermentation, converting sugar into citric acid.

Microorganisms play a dual role in the food industry. On the one hand, these are cultural microorganisms, on the other hand, an infection gets into food production, i.e. foreign (wild) microorganisms. Wild microorganisms are common in nature (on berries, fruits, in the air, water, soil) and from the environment get into production.

Disinfection is an effective way to destroy and suppress the development of foreign microorganisms in order to comply with the correct sanitary and hygienic regime at food enterprises.

Importance of bacteria in our life. The discovery of penicillin and the development of medicine. The results of the use of antibiotics in the plant and animal world. What are probiotics, the principle of their action on the body of people and animals, plants, the benefits of using.

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

The use of microorganisms in medicine, agriculture; benefits of probiotics

Rodnikova Inna

INTRODUCTION

People acted as biotechnologists for thousands of years: they baked bread, brewed beer, made cheese, and other lactic acid products using various microorganisms and were not even aware of their existence.

Actually, the term “biotechnology” itself appeared in our language not so long ago, instead of it the words “industrial microbiology”, “technical biochemistry”, etc. were used. Probably, fermentation was the oldest biotechnological process. This is evidenced by the description of the process of making beer, discovered in 1981.

during the excavations of Babylon on a tablet, which dates back to about the 6th millennium BC. e. In the 3rd millennium BC. e. the Sumerians produced up to two dozen types of beer. No less ancient biotechnological processes are winemaking, baking and obtaining lactic acid products.

From the foregoing, we see that for quite a long time, human life has been inextricably linked with living microorganisms. And if for so many years people have successfully, albeit unconsciously, “collaborated” with bacteria, it would be logical to ask the question - why, in fact, do you need to expand your knowledge in this area?

After all, everything seems to be fine anyway, we know how to bake bread and brew beer, make wine and kefir, what else do you need? Why do we need Biotechnology? Some answers can be found in this abstract.

MEDICINE AND BACTERIA

Throughout the history of mankind (until the beginning of the twentieth century), families have had many children because.

very often children did not live to adulthood, they died from a variety of diseases, even from pneumonia, which is easily curable in our time, to say nothing of such serious diseases as cholera, gangrene, and plague. All these diseases are caused by pathogens and were considered incurable, but finally, medical scientists realized that other bacteria, or an extract from their enzymes, could overcome the "evil" bacteria.

This was first noticed by Alexander Fleming on the example of elementary mold.

It turned out that some types of bacteria get along well with mold, but streptococci and staphylococci did not develop in the presence of mold.

Numerous previous experiments with the reproduction of harmful bacteria have shown that some of them are capable of destroying others and do not allow their development in the general environment. This phenomenon was called "antibiosis" from the Greek "anti" - against and "bios" - life. Working on finding an effective antimicrobial agent, Fleming was well aware of this. He had no doubt that on the cup with the mysterious mold he had encountered the phenomenon of antibiosis. He began to carefully examine the mold.

After some time, he even managed to isolate an antimicrobial substance from the mold. Since the mold he was dealing with had the specific Latin name Penicilium notatum, he named the resulting substance penicillin.

Thus, in 1929, in the laboratory of the London hospital of St. Mary was born the well-known penicillin.

Preliminary tests of the substance on experimental animals showed that even when injected into the blood, it does not cause harm, and at the same time, in weak solutions, it perfectly suppresses streptococci and staphylococci.

The role of microorganisms in food production technology

Fleming's assistant, Dr. Stuart Greddock, who fell ill with purulent inflammation of the so-called maxillary cavity, was the first person who decided to take an extract of penicillin.

He was injected into the cavity with a small amount of extract from the mold, and after three hours it was possible to make sure that his state of health had improved significantly.

Thus, the era of antibiotics began, which saved millions of lives, both in peacetime and in times of war, when the wounded died not from the severity of the wound, but from the infections associated with them. In the future, new antibiotics were developed, based on penicillin, methods for their production for widespread use.

BIOTECHNOLOGY AND AGRICULTURE

The result of a breakthrough in medicine was a rapid demographic rise.

The population increased dramatically, which means that more food was needed, and due to the deterioration of the environment due to nuclear tests, the development of industry, the depletion of the humus of cultivated land, many diseases of plants and livestock appeared.

At first, people treated animals and plants with antibiotics and this brought results.

Let's take a look at these results. Yes, if you treat vegetables, fruits, herbs, etc. during the growing season with strong fungicides, this will help suppress the development of some pathogens (not all and not completely), but, firstly, this leads to the accumulation of poisons and toxins in the fruits, which means that the useful qualities of the fetus are reduced, and secondly, harmful microbes quickly develop immunity to substances that poison them, and subsequent treatments should be carried out with more and more powerful antibiotics.

The same phenomenon is observed in the animal world, and, unfortunately, in humans.

In addition, antibiotics cause a number of negative consequences in the body of warm-blooded animals, such as dysbacteriosis, fetal deformities in pregnant women, etc.

How to be? Nature itself answers this question! And that answer is PROBIOTICS!

The leading institutes of biotechnology and genetic engineering have long been engaged in the development of new and selection of known microorganisms that have amazing viability and the ability to “win” in the fight against other microbes.

These elite strains such as "bacillus subtilis" and "Licheniformis" are widely used to treat people, animals, plants incredibly effectively and completely safely.

How is this possible? And here's how: in the body of people and animals necessarily contains a lot of necessary bacteria. They are involved in the processes of digestion, the formation of enzymes and make up almost 70% of the human immune system. If for any reason (taking antibiotics, malnutrition) a person’s bacterial balance is disturbed, then he is unprotected from new harmful microbes and in 95% of cases he will get sick again.

The same applies to animals. And elite strains, getting into the body, begin to actively multiply and destroy the pathogenic flora, because. already mentioned above, they have greater viability. Thus, with the help of strains of elite microorganisms, it is possible to maintain a macro organism in health without antibiotics and in harmony with nature, since by themselves, being in the body, these strains bring only benefit and no harm.

They are better than antibiotics also because:

The answer of the microworld to the introduction of superantibiotics into business practice is obvious and follows from the experimental material already at the disposal of scientists - the birth of a supermicrobe.

Microbes are surprisingly perfect self-developing and self-learning biological machines capable of memorizing in their genetic memory the mechanisms of protection they have created against the harmful effects of antibiotics and transmitting information to their descendants.

Bacteria are a kind of "bioreactor" in which enzymes, amino acids, vitamins and bacteriocins are produced, which, like antibiotics, neutralize pathogens.

However, there is neither addiction to them, nor side effects typical of the use of chemical antibiotics. On the contrary, they are able to cleanse the intestinal walls, increase their permeability to essential nutrients, restore the biological balance of the intestinal microflora and stimulate the entire immune system.

Scientists took advantage of the natural way for nature to maintain the health of the macroorganism, namely, from the natural environment, they isolated bacteria - saprophytes, which have the ability to suppress the growth and development of pathogenic microflora, including in the gastrointestinal tract of warm-blooded animals.

Millions of years of evolution of living things on the planet have created such wonderful and perfect mechanisms for suppressing pathogenic microflora with non-pathogenic ones that there is no reason to doubt the success of this approach.

Non-pathogenic microflora in the competition wins in the vast majority of cases, and if it were not so, we would not be on our planet today.

Based on the foregoing, scientists producing fertilizers and fungicides for agricultural use have also tried to move from a chemical to a biological view.

And the results were not slow to show themselves! It turned out that the same bacillus subtilis successfully fight as many as seventy varieties of pathogenic representatives that cause such diseases of horticultural crops as bacterial cancer, fusarium wilt, root and root rot, etc., previously considered incurable plant diseases that could not be treated. handle NOT A SINGLE FUNGICIDE!

In addition, these bacteria have a clearly positive effect on the vegetation of the plant: the period of filling and ripening of fruits is reduced, the useful qualities of fruits increase, the content of nitrates in them decreases, etc.

toxic substances, and most importantly - the need for mineral fertilizers is significantly reduced!

Preparations containing strains of elite bacteria are already taking first place at Russian and international exhibitions, they are winning medals for efficiency and environmental friendliness. Small and large agricultural producers have already begun their active use, and fungicides and antibiotics are gradually becoming a thing of the past.

The Bio-Ban company's products are Flora-S and Fitop-Flora-S, which offer dry peat-humic fertilizers containing concentrated humic acids (and saturated humus is the key to an excellent harvest) and a bacterial strain "bacillus subtilis" for disease control. Thanks to these preparations, it is possible to restore depleted land in a short time, increase land productivity, protect your crop from diseases, and most importantly, it is possible to get excellent yields in risky farming areas!

I think the above arguments are enough to appreciate the benefits of probiotics and understand why scientists say that the twentieth century is the century of antibiotics, and the twenty-first is the century of probiotics!

The main groups of microorganisms used in the food industry

It should be maximum when receiving medicines and chemicals. The requirements for sterility in the production of alcoholic beverages are less stringent.

Such fermentation processes are said to be "protected" because the conditions that are created in the environment are such that only certain microorganisms can grow in them. For example, in the production of beer, the growth medium is simply boiled rather than sterilized; the fermenter is also used clean, but not sterile.

Getting culture. Before starting the fermentation process, it is necessary to obtain a pure, highly productive culture. Pure cultures of microorganisms are stored in very small volumes and under conditions that ensure its viability and productivity; this is usually achieved by storage at a low temperature.

The fermenter can hold several hundred thousand liters of culture medium, and the process is started by introducing culture (inoculum) into it, constituting 1-10% of the volume in which fermentation will take place. Thus, the initial culture should be grown in stages (with subculturing) until the level of microbial biomass is reached, sufficient for the microbiological process to proceed with the required productivity.

It is absolutely necessary to keep the culture clean all this time, preventing it from being contaminated by foreign microorganisms.

Preservation of aseptic conditions is possible only with careful microbiological and chemical-technological control.

Growth in an industrial fermenter (bioreactor). Industrial microorganisms must grow in the fermenter under optimal conditions to form the desired product.

These conditions are strictly controlled to ensure microbial growth and product synthesis. The design of the fermenter should allow you to control the growth conditions - a constant temperature, pH (acidity or alkalinity) and the concentration of oxygen dissolved in the medium.

A conventional fermenter is a closed cylindrical tank in which the medium and microorganisms are mechanically mixed.

Air, sometimes saturated with oxygen, is pumped through the medium. The temperature is controlled by water or steam passing through the tubes of the heat exchanger. Such a stirred fermenter is used in cases where the fermentation process requires a lot of oxygen. Some products, on the contrary, are formed under anoxic conditions, and in these cases fermenters of a different design are used. Thus, beer is brewed at very low concentrations of dissolved oxygen, and the contents of the bioreactor are not aerated or stirred.

Some brewers still traditionally use open containers, but in most cases, the process takes place in closed non-aerated cylindrical containers, tapering downwards, which contributes to the sedimentation of the yeast.

The production of vinegar is based on the oxidation of alcohol to acetic acid by bacteria.

Acetobacter. The fermentation process takes place in containers called acetaters, with intensive aeration. Air and medium are sucked in by a rotating agitator and enter the walls of the fermenter.

Isolation and purification of products. At the end of the fermentation, the broth contains microorganisms, unused nutrient components of the medium, various waste products of microorganisms, and the product that they wanted to obtain on an industrial scale. Therefore, this product is purified from other components of the broth.

When receiving alcoholic beverages (wine and beer), it is enough to simply separate the yeast by filtration and bring the filtrate to standard. However, individual chemicals obtained by fermentation are extracted from a complex broth.

Although industrial microorganisms are specifically selected for their genetic properties so that the yield of the desired product of their metabolism is maximized (in a biological sense), its concentration is still small compared to that achieved by production based on chemical synthesis.

Therefore, one has to resort to complex isolation methods - solvent extraction, chromatography and ultrafiltration. Processing and disposal of fermentation waste. In any industrial microbiological processes, waste is generated: broth (liquid left after the extraction of the product of production); cells of used microorganisms; dirty water, which washed the installation; water used for cooling; water containing trace amounts of organic solvents, acids and alkalis.

Liquid waste contains many organic compounds; if they are dumped into rivers, they will stimulate the intensive growth of natural microbial flora, which will lead to the depletion of oxygen in river waters and the creation of anaerobic conditions. Therefore, the waste is subjected to biological treatment before disposal in order to reduce the content of organic carbon. Industrial microbiological processes can be divided into 5 main groups: 1) cultivation of microbial biomass; 2) obtaining metabolic products of microorganisms; 3) obtaining enzymes of microbial origin; 4) obtaining recombinant products; 5) biotransformation of substances.

microbial biomass. Microbial cells themselves can serve as the final product of the manufacturing process. On an industrial scale, two main types of microorganisms are produced: yeast, which is necessary for baking, and single-celled microorganisms, used as a source of proteins that can be added to human and animal food.

Baker's yeast has been cultivated in large quantities since the early 20th century. and was used as a food product in Germany during the First World War.

However, the technology for the production of microbial biomass as a source of food proteins was developed only in the early 1960s. A number of European companies drew attention to the possibility of growing microbes on such a substrate as hydrocarbons to obtain the so-called.

protein of unicellular organisms (BOO). A technological triumph was the development of a product added to livestock feed, consisting of dried microbial biomass grown on methanol.

The process was carried out in a continuous mode in a fermenter with a working volume of 1.5 million liters

However, due to the rise in prices for oil and products of its processing, this project became economically unprofitable, giving way to the production of soybean and fishmeal. By the end of the 1980s, the BOO plants were dismantled, which put an end to the turbulent but short period of development of this branch of the microbiological industry. Another process turned out to be more promising - obtaining fungal biomass and fungal mycoprotein protein using carbohydrates as a substrate.

metabolic products. After introducing the culture into the nutrient medium, a lag phase is observed, when no visible growth of microorganisms occurs; this period can be considered as a time of adaptation. Then the growth rate gradually increases, reaching a constant, maximum value for the given conditions; such a period of maximum growth is called the exponential, or logarithmic, phase.

Gradually, growth slows down, and the so-called. stationary phase. Further, the number of viable cells decreases, and growth stops.

Following the kinetics described above, it is possible to follow the formation of metabolites at different stages.

In the logarithmic phase, products vital for the growth of microorganisms are formed: amino acids, nucleotides, proteins, nucleic acids, carbohydrates, etc. They are called primary metabolites.

Many primary metabolites are of significant value. So, glutamic acid (more precisely, its sodium salt) is part of many foods; lysine is used as a food additive; phenylalanine is the precursor to the sugar substitute aspartame.

Primary metabolites are synthesized by natural microorganisms in quantities necessary only to meet their needs. Therefore, the task of industrial microbiologists is to create mutant forms of microorganisms - super-producers of the corresponding substances.

Significant progress has been made in this area: for example, it was possible to obtain microorganisms that synthesize amino acids up to a concentration of 100 g/l (for comparison, wild-type organisms accumulate amino acids in milligram amounts).

In the growth retardation phase and in the stationary phase, some microorganisms synthesize substances that are not formed in the logarithmic phase and do not play a clear role in metabolism. These substances are called secondary metabolites. They are synthesized not by all microorganisms, but mainly by filamentous bacteria, fungi and spore-forming bacteria. Thus, producers of primary and secondary metabolites belong to different taxonomic groups. If the question of the physiological role of secondary metabolites in producer cells was the subject of serious discussions, then their industrial production is of undoubted interest, since these metabolites are biologically active substances: some of them have antimicrobial activity, others are specific inhibitors of enzymes, and others are growth factors. , many have pharmacological activity.

Obtaining such substances served as the basis for the creation of a number of branches of the microbiological industry. The first in this series was the production of penicillin; The microbiological method for producing penicillin was developed in the 1940s and laid the foundation for modern industrial biotechnology.

The pharmaceutical industry has developed highly complex methods for screening (mass testing) of microorganisms for the ability to produce valuable secondary metabolites.

Initially, the purpose of screening was to obtain new antibiotics, but it was soon discovered that microorganisms also synthesize other pharmacologically active substances.

During the 1980s, the production of four very important secondary metabolites was established. These were: cyclosporine, an immunosuppressive drug used as an agent to prevent rejection of implanted organs; imipenem (one of the modifications of carbapenem) - a substance with the widest spectrum of antimicrobial activity of all known antibiotics; lovastatin - a drug that lowers blood cholesterol levels; Ivermectin is an anthelmintic used in medicine to treat onchocerciasis, or "river blindness", as well as in veterinary medicine.

Enzymes of microbial origin. On an industrial scale, enzymes are obtained from plants, animals and microorganisms. The use of the latter has the advantage of allowing the production of enzymes in large quantities using standard fermentation techniques.

In addition, it is incomparably easier to increase the productivity of microorganisms than that of plants or animals, and the use of recombinant DNA technology makes it possible to synthesize animal enzymes in microorganism cells.

Enzymes obtained in this way are mainly used in the food industry and related fields. The synthesis of enzymes in cells is genetically controlled, and therefore the available industrial microorganisms-producers were obtained as a result of a directed change in the genetics of wild-type microorganisms.

recombinant products. Recombinant DNA technology, better known as "genetic engineering", allows the genes of higher organisms to be incorporated into the bacterial genome. As a result, bacteria acquire the ability to synthesize "foreign" (recombinant) products - compounds that previously could only be synthesized by higher organisms.

On this basis, many new biotechnological processes have been created for the production of human or animal proteins that were not previously available or used with great health risks.

The term "biotechnology" itself became popular in the 1970s in connection with the development of methods for the production of recombinant products. However, this concept is much broader and includes any industrial method based on the use of living organisms and biological processes.

The first recombinant protein produced on an industrial scale was human growth hormone. For the treatment of hemophilia, one of the proteins of the blood coagulation system, namely the factor

VIII. Before methods were developed to obtain this protein using genetic engineering, it was isolated from human blood; the use of such a drug has been associated with a risk of infection with the human immunodeficiency virus (HIV).

For a long time, diabetes mellitus has been successfully treated with animal insulin. However, scientists believed that the recombinant product would create fewer immunological problems if it could be obtained in its pure form, without impurities from other peptides produced by the pancreas.

In addition, the number of diabetic patients was expected to increase over time due to factors such as changes in dietary habits, improved medical care for pregnant women with diabetes (and, as a result, an increase in the frequency of genetic predisposition to diabetes), and finally the expected increase the life expectancy of diabetic patients.

The first recombinant insulin went on the market in 1982, and by the end of the 1980s it had practically replaced animal insulin.

Many other proteins are synthesized in the human body in very small quantities, and the only way to obtain them on a scale sufficient for clinical use is through recombinant DNA technology. These proteins include interferon and erythropoietin.

Erythropoietin, together with myeloid colony-stimulating factor, regulates the formation of blood cells in humans. Erythropoietin is used to treat anemia associated with kidney failure and may find use as a platelet booster in cancer chemotherapy.

Biotransformation of substances. Microorganisms can be used to convert certain compounds into structurally similar, but more valuable substances. Since microorganisms can exert their catalytic action in relation to only certain specific substances, the processes occurring with their participation are more specific than purely chemical ones. The best known biotransformation process is the production of vinegar by converting ethanol to acetic acid.

But among the products formed during biotransformation, there are also such highly valuable compounds as steroid hormones, antibiotics, prostaglandins. see also GENETIC ENGINEERING. Industrial Microbiology and Advances in Genetic Engineering(special issue of Scientific American).

M., 1984
Biotechnology. Principles and application. M., 1988

Production Human use of microorganisms.

Microorganisms are widely used in the food industry, household, microbiological industry to produce amino acids, enzymes, organic acids, vitamins, etc.

Classical microbiological industries include winemaking, brewing, making bread, lactic acid products, and food vinegar. For example, winemaking, brewing and the production of yeast dough are impossible without the use of yeast, which is widely distributed in nature.

The history of industrial production of yeast began in Holland, where in 1870 ᴦ. The first yeast factory was founded. The main product was pressed yeast with a moisture content of about 70%, which could be stored for only a few weeks.

Long-term storage was impossible, since the pressed yeast cells remained alive and retained their activity, which led to their autolysis and death. Drying has become one of the methods of industrial preservation of yeast. In dry yeast at low humidity, the yeast cell is in an anabiotic state and can persist for a long time.

The first dry yeast appeared in 1945 ᴦ. In 1972 ᴦ. the second generation of dry yeast appeared, the so-called instant yeast.

The use of microorganisms in the food industry

Since the mid-1990s, a third generation of dry yeast has emerged: baker's yeast. Saccharomyces cerevisiae, which combine the virtues of instant yeast with a highly concentrated complex of specialized baking enzymes in one product.

This yeast allows not only to improve the quality of bread, but also to actively resist the process of staleness.

baker's yeast Saccharomyces cerevisiae are also used in the production of ethyl alcohol.

Winemaking uses many different strains of yeast to produce a unique brand of wine with unique qualities.

Lactic acid bacteria are involved in the preparation of foods such as sauerkraut, pickled cucumbers, pickled olives, and many other pickled foods.

Lactic acid bacteria convert sugar into lactic acid, which protects food from putrefactive bacteria.

With the help of lactic acid bacteria, a large assortment of lactic acid products, cottage cheese, and cheese are prepared.

At the same time, many microorganisms play a negative role in human life, being pathogens of human, animal and plant diseases; they can cause spoilage of foodstuffs, destruction of various materials, etc.

To combat such microorganisms, antibiotics were discovered - penicillin, streptomycin, gramicidin, etc., which are metabolic products of fungi, bacteria and actinomycetes.

Microorganisms provide humans with the necessary enzymes.

Thus, amylase is used in the food, textile, and paper industries. The protease causes the degradation of proteins in various materials. In the East, mushroom protease has been used for centuries to make soy sauce.

Today it is used in the manufacture of detergents. When preserving fruit juices, an enzyme such as pectinase is used.

Microorganisms are used for wastewater treatment, food industry waste processing. The anaerobic decomposition of waste organic matter produces biogas.

In recent years, new productions have appeared.

Carotenoids and steroids are obtained from mushrooms.

Bacteria synthesize many amino acids, nucleotides, and other reagents for biochemical research.

Microbiology is a rapidly developing science, the achievements of which are largely associated with the development of physics, chemistry, biochemistry, molecular biology, etc.

To successfully study microbiology, knowledge of the listed sciences is required.

This course focuses on food microbiology.

Many microorganisms live on the surface of the body, in the intestines of humans and animals, on plants, on food and on all objects around us. Microorganisms consume a wide variety of food, extremely easily adapt to changing living conditions: heat, cold, lack of moisture, etc.

n. Οʜᴎ multiply very quickly. Without knowledge of microbiology, it is impossible to competently and effectively manage biotechnological processes, maintain the high quality of food products at all stages of its production and prevent the consumption of products containing pathogens of foodborne diseases and poisoning.

It should be emphasized that microbiological studies of food products, not only from the point of view of technological features, but also, no less important, from the point of view of their sanitary and microbiological safety, are the most difficult object of sanitary microbiology.

This is explained not only by the diversity and abundance of microflora in food products, but also by the use of microorganisms in the production of many of them.

In this regard, in the microbiological analysis of food quality and safety, two groups of microorganisms should be distinguished:

- specific microflora;

- nonspecific microflora.

specific- ϶ᴛᴏ cultural races of microorganisms that are used to prepare a particular product and are an indispensable link in the technology of its production.

Such microflora is used in the technology for producing wine, beer, bread, and all fermented milk products.

Nonspecific- ϶ᴛᴏ microorganisms that enter food from the environment, contaminating them.

Among this group of microorganisms, saprophytic, pathogenic and conditionally pathogenic, as well as microorganisms that cause spoilage of products are distinguished.

The degree of pollution depends on many factors, which include the correct procurement of raw materials, their storage and processing, compliance with technological and sanitary conditions for the production of products, their storage and transportation.