Self-esteem and self-love 

What do fungi eat. Mold: what is it, why does it appear? What are mushrooms

Good day, dear visitors of the project “Good IS! ", section" "!

In today's article, we will talk about such unpleasant "roommates" as mold and other types of fungus. We will also look at why mold is dangerous, what types of it spoil the lives of many people, and also consider how to get rid of mold. But first, let's define what a fungus or mold is.

Mushrooms ( lat. Fungi or Mycota) - the kingdom of wildlife, uniting eukaryotic organisms, combining some features of both plants and animals. Mushrooms are studied by science mycology, which is considered a branch of botany, since mushrooms were previously assigned to the plant kingdom.

What we see on affected walls, concrete, wallpaper, hardwood floors, tiles in the bathroom and other places that has green, black, brown and gray tones, and also emits a specific smell - various types of mushrooms or as many people say - fungus.

Now let's look at some types of fungus that harm our homes.

Species of fungus and other related pests

mold fungus- various fungi (mainly zygo- and ascomycetes) forming branching mycelia without large, easily visible to the naked eye, fruiting bodies.

Mold- This is a colony of a single-celled fungus that develops from spores, which in a “preserved” state are constantly present in the air in large quantities. Spores “wake up” for intensive reproduction as soon as favorable conditions appear for this: high humidity and heat.

Molds (mold) grow on concrete, paint or stone. They can be observed in the form of spots or dots of black, brown, blue or green colors. There are also luminous, phosphorescent colonies of mushrooms, but they are not terrible for the facade. Mold destroys building and finishing material almost to the ground, forcing more and more repairs, and sometimes even restructuring of buildings.

The color of this type of mold depends not only on its type, but also on the stage of development, as well as the material on which it grows. As a rule, the following strains have black color:

Ulocladium- the fourth group of pathogenicity, affects not only materials, but also products. Very picky about the presence of moisture.

Cladosporium- on the initial stage colorless, except black, can take on a wide range of colors. The most dangerous for seeds and plants, not picky about moisture, can develop at low temperatures. The most common outdoor fungus in the summer. Some species feed on diesel fuel and fuels and lubricants, which is why they got the name kerosene mushroom. Also affects other types of materials. When conducting mycological examinations, we have it in third place in terms of frequency of detection, following Penicillium and Aspergillus.

Penicillium- mushrooms of this family play a huge role environment, are actively used in pharmaceuticals for the preparation of drugs, B Food Industry for the preparation of gourmet cheese with white mold. But some strains such as Penicillum marneffei and Penicillium spp. belong to the 3rd and 4th groups of pathogenicity and pose a significant danger to human health, in addition, they are very often found in apartments.

Alternaria- a very common fungus of the fourth pathogenicity group. It most commonly affects fruits and vegetables, but can also grow on the skin and in the respiratory tract in humans. Sometimes it has a gray color, has about 300 strains.

Aspergillus- belongs to the higher mold fungi, and, depending on the type, belongs to the 4th and 3rd groups of pathogenicity. This type of mold causes aspergillosis in humans and animals. The mycelium itself is initially white, but its spores are black. Most often found indoors.

Chaetomium- typically painted black. Often causes allergies in people. The main danger is when it enters the digestive tract. There are known deaths caused by this fungus.

Phoma- the fourth group of pathogenicity. Almost always, the mycelium is black, and the spores are colorless.

Wallemia- painted black, does not pose a serious danger to humans, but belongs to the type of Xerophiles, that is, it can grow in conditions of low humidity and high temperatures, which causes some problems when dealing with it.

White mold is much less of a concern to people than black mold. Most often it can be found on the ground, wood, plants, bread and cheese. In apartments, it is found, as a rule, in flower pots and quite rarely on the walls. Often efflorescence on the wall is mistaken for white mold. Distinguishing efflorescence from a fungus is quite simple and without a microscope. The efflorescence has a crystalline structure and crumbles in the hands, and the fungus warms up. Naturally, gloves must be worn before checking, because. mold cannot be handled. If white mold has grown on the ground in a flower pot, some strains will die if watered regularly with dilute citric acid.

In the cheese industry, various types of mold, which is commonly called noble, are actively used to make gourmet cheeses. Such mushrooms have nothing to do with house mold.

Blue fungi affect the fiber of the tree, and the surface of a wooden house is painted not at all in a noble gray-blue color. Blue damage is not only aesthetic. It easily penetrates the paint film and thus creates a kind of "water pipelines". It paves the way for water to penetrate, which in turn increases the moisture content of the wood. Then nothing prevents the penetration and fixing in the neighborhood and mold. Pine is especially susceptible to blue.

Rotting fungi also attack exclusively wood. There are several types of rot - bacterial, brown and white.

Bacterial rot eats away wood from the inside. The affected material noticeably grays or darkens, and its strength deteriorates markedly - a bacterium that causes local decomposition of cellulose.

White rot destroys not only cellulose, but also lignin, therefore, the color of the wood does not change much.

Brown rot causes wood to split.

When wet rot appears, stripes from yellowish to dark brown and even black will appear on the material, and after them - cracks. If dry, then the affected tree will acquire Brown color, will shrink and soon begin to split along and across the fibers.

actinomycetes

Actinomycetes are a cross between fungi and algae. They not only spoil the appearance, but also destroy the fibers, and also cause softening of the wood, causing irreparable damage to wooden structures. Why do you need to know all this? To effectively control the pest. After all, if you use chemicals designed to combat wet rot, for example, for dry rot, then this will lead to the exact opposite result: the fungus will begin to develop faster.

Efflorescence is a white, less often colored, salt or alkaline coating that occurs on the walls, which is based on insoluble sulfates, carbonates and silicates. It is formed due to the movement of water along with salts inside the material. In dry weather, the salty non-freezing solution rushes to the surface of the rock. Water evaporates, and salts crystallize, remaining on the wall in the form white plaque. Facades made of concrete and brick, as well as those finished with plaster or lined with marble, are usually affected. The same crystallization occurs inside the material. Crystals growing in the pores of the material begin to wedged the walls of the pores. As a result, cracks appear, and the material is destroyed.

The most terrible enemy of wooden houses is the white house mushroom. In one month, he is able to "eat" a four-centimeter oak floor, so earlier in the villages the hut that this fungus hit was immediately burned to save other buildings from infection.

What is dangerous mold and other types of fungus

You can often see questions on the net: “How dangerous is mold?”, “Is mold harmful?”. The answer to them is "Yes". Mold is quite dangerous, both for building materials and for human health.

Building materials deform over time, and can become one of the factors in the destruction of a building. For example, in a short time, mold turns a tree into dust, but what if the house is built of wood? May the Lord keep!

Mold affects human health through:

- direct contact with the skin;
- through the use of moldy food;
through the respiratory and circulatory systems.

So, getting into the body, mold spores can cause a number of diseases, sometimes even severe ones. This is due to the fact that the spores of certain types of mold are toxic, and multiply at an extraordinary rate: 1m 2 of mold releases billions of spores into the air per day!

The consequences due to contact with mold are primarily:

- allergic skin diseases (dermatoses, mycoses, fungi);
- diseases of the upper respiratory tract (colds, cough, asthma, pneumonia, sinusitis, sinusitis, nosebleeds, etc.);
- diseases of the musculoskeletal system or articular-rheumatic;
- headaches, dizziness;
- nausea, indigestion;
- general depletion of the body;

Prolonged exposure may result in internal bleeding, kidney and liver damage, and emphysema.

Children, the elderly, and people with weakened immune systems due to illness, chemotherapy, antibiotics, etc. are especially susceptible to severe illness after exposure to fungal contamination.

It is possible to diagnose mycosis or the presence of an allergy to mold in most allergy centers and in a number of laboratories.

So how does mold grow in our homes?

Conditions for the appearance of mold

This requires the following 3 conditions:

1. The presence of mold spores in the air. As a rule, they are transported by air and get into an apartment or house on people, on animals, on food and things.

2. Organic growing medium: paper, wood, concrete, stone, mud, flowers and peat pots, houseplant soil, etc.

3. Favorable microclimate of the room: temperature about +20°С; high humidity (above 70-95%); uneven heating around the perimeter of the room and not working properly or not working ventilation system.

Some types of fungus can appear and multiply rapidly even at 0 ° C.

I want to dwell a little on ventilation issues.

The fact is that if the ventilation system in the room is installed correctly and works correctly, then the movement of air prevents the appearance of mold on the walls, because. the air blows off the spore, and it cannot cling to the surface. In the corners and nooks and crannies, there is no or limited air movement, which is why you can most often see mold in them. In addition, ventilation is necessary to remove excess moisture from the premises, which can be caused by pets, houseplants, frequent washing, coolness in rooms with high humidity outside, uneven heating of rooms, etc. Bathroom, shower room, toilet, sauna, washbasin in the kitchen and other places also emit a certain amount of moisture, which must go somewhere. The situation is especially aggravated by metal-plastic windows, which prevent any draft (if they are correctly installed, of course).

If mold spores are present on the walls, waiting for favorable conditions for growth, but there is not enough moisture, they will not germinate.

So, we can conclude that since we cannot influence the first two reasons, in order to prevent the appearance of mold, the third reason should be dealt with.

Causes of mold

— Bad ventilation system. We have already talked about this. It would be nice to install air conditioning at home, or other systems that are responsible for ventilation in the room. If this is not possible, then you need to ventilate the premises more often.

— Ventilation systems for kitchen, bathroom, toilet. These are rooms with relatively high humidity, and, as a rule, it is very high there, which contributes to the lightning-fast development of mold and other types of fungus. In this case, you need to pay attention to frequent ventilation of the rooms or install a special air conditioning system. For example, some people put fans in the chimneys in these rooms, which increase the extraction of excess moisture, odors, etc.

— The condition of the plumbing. The first symptom is the presence of moisture that occurs along the passage of pipes. Another clue could be footprints on the wall next to the bathroom, about the height of the edge of the tub. As a general rule, accurate drying should help, but if you detect symptoms too late, then the fungus has time to spread too quickly, and then we can not avoid repairs.

— Capillary suction of moisture along the walls of moistened foundations. This is especially common in old buildings due to the lack of waterproofing in them.

— Increased thermal conductivity of corners and heat loss in the end rooms due to the increased area of ​​the outer walls facing the street.

— Freezing of outer walls. If we see a dark coating in the corners and along the edges of the walls, then we can be sure that the wall has been frozen. In this case, they must be thoroughly dried, and then the adhesion of the plaster must be checked.

— Leaking gutters and drains. As a rule, this problem is only visible from the outside, in the form of streaks on the plaster. However, if the humidity is high (for example, during heavy rains), drips may also occur from the center. Often this problem is taken for granted until the situation becomes serious. Leaks left unchecked will only create a real problem in winter when the water freezes in the plaster.

— Moisture coming from the ground. Its presence can be seen in the form of streaks at the junction of the walls with the floor of the first floor or basement. In this case, an examination of the state of the horizontal insulation of the foundation walls can help. If it is damaged, then you should have it repaired, preferably by a specialized company. Before repairs can be carried out, the main walls must be thoroughly dried. An additional problem arises if the floor also turns out to be wet, in which case the problem is difficult to avoid unless the fragment is removed.

Normal for a comfortable existence of a person, this humidity is in the range of 70% - 80%.

To be able to effectively deal with mold and other types of fungus, you should accurately determine the cause of their occurrence. And only in this case it is possible to choose the most effective methods eliminate them and prevent their recurrence.

How to deal with mold

1. After detecting mold-infected areas, they must be moistened with plenty of water. This is done so that during further actions, we do not “launch” additional disputes into the air.

2. Apply special preparations to the affected areas that neutralize the mold and prevent its further spread. It is necessary to apply funds with a margin of 1 m outside the affected area, because. they may have microfungi that are invisible to the eye. I also want to note that it is necessary to treat the affected area 2-3 times, and apply the next layer only after the previous one has dried.

Be sure to follow the instructions on the anti-mold packaging.

3. Arm yourself with a metal brush, or other improvised tool (scraper, drill with a metal brush) and carefully remove the fungus. When stripping, not only paint and wallpaper are removed, but also plaster, and concrete and wood can even be milled.

In severely neglected cases, the fungus manages to develop so much that it penetrates into the deeper layers, especially in porous materials, here the main mycelium is formed in the fungus, and if it is not completely removed, then the external treatment will not eliminate the problem, but will only hide the external traces of manifestation for some time. Therefore, if it is possible to completely replace the fragment, then this should be done. Otherwise, you will need to reach the deepest layers to completely remove the fungus, which can render the site unusable.

After processing, the removed infected fragments must be burned.

4. After work on the destruction of the fungus, a protective coating is applied for a long period of time.

Additional measures and rules in the fight against mold

- When working with drugs, under no circumstances should you work without special protective equipment. In order to avoid even accidental contact with harmful substances, work should be carried out in a mask and protective gloves. Protective equipment is needed not only from the "chemistry" against mold, but also against the spores of the mold itself, which will become even more in the air during the fight, so it is necessary to prevent it from settling in the lungs and the appearance of the disease.

- Be sure to ensure that the area being treated is well ventilated so that the spores do not settle in other areas, and also to provide additional protection from flying mold spores.

- After the end, in order to start using the premises, it is necessary that 48-72 hours pass. Moreover, at this time, the room must be provided with good ventilation.

The best means for removing the fungus are fungicides that have boron compounds in their composition. By the way, boron is also actively used in the fight against ants.

There are universal remedies for removing all types of fungus, but there are also those that are designed only for a certain type. In the latter case, a mandatory consultation with a specialist is necessary, which will help us accurately determine the type of fungus with which we are dealing. It is best, of course, to choose a product of a well-known company. Here are some effective solutions available on the market:

— "Atlas Mykos". Means for removing not only mold, but also other types of fungus, as well as algae, lichen and moss. Available as a concentrate. It can be used wherever there is high humidity, both indoors and outdoors. It must be diluted with water in a ratio of 1:2. It is also suitable for protecting mineral surfaces, then it should be diluted in a ratio of 1:5.

— "Teflex Antimold Express". With this tool, you can treat surfaces made of wood, brick, plastic, concrete and other materials from mold.

— "Izohan Grzybostop". Designed for processing building materials such as concrete and mortar. It fights not only mold, but also other types of fungus.

— "SZAVO"(Savo anti-mold). One of the most popular mold killers. The agent is especially effective in places of high humidity, such as bathrooms, toilets, kitchens, showers, swimming pools, baths and saunas, basements, food warehouses, etc.

The effect is 100% destruction of all vegetative forms of mold, yeast, algae, as well as general disinfection. The drug is extremely easy to use and does not require pre-training surface and subsequent rinsing. Drying, the product does not leave marks on the treated areas.

— Belinka. A broad spectrum anti-mold agent designed to kill mold and mildew. Easy to use and safe for humans, the drug is fast acting and effective. The tool is suitable for processing both internal and external surfaces.

— "Spectrum Fungicide". It fights fungus on walls, plaster, wood and paint coatings. It is intended for use in places particularly exposed to the appearance of moisture, both inside and outside the building.

— Antialga B25. Aqueous dispersion of algicine and fungicide, effective against various types molds and fungi. It has low toxicity. Added to paint. Leaves no unpleasant odor.

— "PS 50". An excellent tool for removing algae from concrete surfaces, it is also good for removing mold and mildew from drywall, plaster and wood.

— Well Done. State-of-the-art anti-mold, algae and fungus. It works simply, effectively and with instant visible results. Antibacterial. Cleans, disinfects and prevents the appearance of mold and fungus on windows, ventilation systems and bathrooms. It is used for the rehabilitation of moldy wood, plaster and paint in the interior and exterior.

— "Snowball Impregnation". Wall antifungal agent that fights fungus, mold, algae, moss and lichen from masonry, plaster and coatings. Suitable for use on interior and exterior walls.

— "Boramon S30". Antiseptic agent for the protection of walls, plaster, paint coatings and wood against fungi. Impregnate for wood: protects against house and mold fungi, algae, bacteria and insect larvae - technical pests of wood: etc. Significantly increases the biological resistance of elements of wooden building structures. Included in a permanent connection with wood, does not increase the degree of its flammability.

— "Titan" Fungicide. Thanks to it, we can remove fungus and mold from walls painted with paints (both internal and external) without the need to remove the layer. This mold remedy can also be used to prevent mold.

— "Mellerud". Destroys all types of a mold in the house, a sauna and the pool. Just spray! Works instantly. Eliminates mold, fungi, bacteria and algae. Suitable for processing, tile joints, walls, ceilings, masonry, wood, artificial materials.

Disinfects, prevents the appearance of mold. Also ideal for wallpaper and painted walls. 500 ml is enough for 5-8 m2.

— "Boramon". Mold and fungus control agent. For use both indoors and outdoors, both on plaster, masonry and wood.

— "Schimmelentferner Dufa". Water-based spray for quick removal of mold, algae, moss. It is applied to internal and external works. Contains chlorine. Easy to use. Disinfectant.

— Astonish. Very effective remedy for removing black spots from surfaces without scraping. Ideal for window frames, plastic shower curtains, tiles and concrete.

In addition, there are many paints on the market with the addition of agents that destroy the fungus. It is possible to distinguish fungicidal dispersion paints, silicate paints and silicone resin paints. They are used both inside and outside, just remember to pre-prime the surface.

Before buying any of the above anti-mold and fungus, look for annotations to them, and determine if the product you have chosen is right for your situation, because. each of them may have a different purpose.

— Bleach. Using ordinary bleach, you can get rid of almost all types of mold in the house. The active substance in it is sodium hypochlorite. It kills both mold and its spores. Bleach can clean bathroom tiles, glass, floors, but many things become discolored and deteriorated under the influence of bleach. In addition, bleach gives off harsh and toxic fumes and corrodes the skin of the hands, so be sure to make sure that the area is well ventilated before proceeding with the removal of mold with bleach. You should also wear rubber gloves to protect your hands. The surface is treated with a mixture of 1 part bleach with 10 parts water.

— Tea tree oil. Mix 2 teaspoons (10 ml) of tea tree oil with 2 cups (500 ml) of water in a spray bottle, shake vigorously to combine the substances. Apply the solution to the affected area. Do not rinse off the solution, allowing it to soak into the mold. Repeat if necessary. Tea tree oil can be expensive and has a strong smell, but the smell dissipates within a few days.

— Baking soda It also helps to get rid of mold. It kills fungus and is known as a natural and safe household cleaner. Unlike other cleaners that contain harsh chemicals, baking soda won't harm your family or pets. A teaspoon of soda is dissolved in a glass of water and sprayed on the surface affected by mold. You can simply rinse the surface and things with a sponge in a soda solution. It is better not to completely wash off the soda from the surface, it effectively protects it from the reappearance of dangerous contaminants.

— grapefruit seed extract. Mix 20 drops of grapefruit seed extract and 2 cups (500 ml) of water in a spray bottle. Shake to mix the ingredients and apply to the affected area. Apply the solution to the affected area, and do not wash it off the surface. You can blot the area with a dry paper towel, but do not wash it with water.

— Hydrogen peroxide. Hydrogen peroxide is also suitable for mold control. it is an antibacterial and antifungal agent. A 3% peroxide solution can be bought at any pharmacy, it is non-toxic and does not emit a pungent odor. Hydrogen peroxide is effective in removing mildew on many materials, but it also has a bleaching effect, so use with caution on fabrics and painted surfaces.

— Vinegar. Table vinegar is a weak acid and can kill many common types of mold. It has an odor but does not give off dangerous fumes like bleach. To get rid of mold, vinegar is applied to moldy surfaces with a spray bottle or wiped with a damp cloth. Usually, after an hour, they rinse with water and ventilate the room. To prevent the appearance of mold, vinegar is sprayed every week on the problem area.

— Ammonia also used to kill mold. Like bleach, it easily kills mold on hard, non-porous surfaces such as tile or glass, but it is not effective at removing mildew from porous materials. To get rid of mold with ammonia, mix it in half with water and spray the resulting mixture on the infected area. Leave for a few hours, then rinse. The pungent smell of ammonia can cause headaches and sore throats. It is dangerous to mix bleach with ammonia, as this releases toxic gas.

— Bura. Cover the affected area with borax. To prepare the mixture, you need to mix 1 cup (250 ml) borax and 4 liters hot water. After the substance is completely dissolved, pour the solution into a spray bottle and apply to the area with mold. Clean with a brush after a few minutes. Do not rinse off the solution. If you are using less water, you can make a paste. This paste can be applied to the moldy area for a few minutes. Scrape off the paste and clean the area with a brush. Borax is a natural, white mineral powder. It is used as a fungicide, pesticide, herbicide, disinfectant and deodorant.

Prevention of mold and other types of fungus

To prevent the appearance of a fungus in the future, first of all, it is necessary to establish the cause of its appearance, and in the future to use those materials and means that helped you get rid of it. But the main measure is the elimination of high humidity.

Measures to prevent the appearance of mold and other types of fungus are as follows:

- Ventilate the room more often;

- Do not close the doors tightly in rooms with high humidity (bathroom, etc.). This is necessary to equalize the temperature and humidity in these rooms.

- Put things in order with the ventilation system. This issue can be attributed, for example, the installation of air conditioning. In addition, because mold appears primarily from its spores that have appeared in the room through the air, you can install an air cleaner that will filter the air in the room and give additional protection.

- In the toilet, bathroom and other rooms with high humidity, you can install fans in the chimneys. In some cases, hoods can also be installed.

— Heating and ventilation must function at the level of design standards. The walls of the premises must have heat resistance strictly in accordance with the project, and the heating devices are correctly placed in the end rooms.

- When fighting mold, clean and finish, if necessary, to the level of a concrete or brick surface to completely remove a possible breeding ground for fungus in the future.

- After the destruction of mold and other fungi, during repair work, use special tools that, in addition to their basic properties and purpose, also have the ability to prevent the appearance of fungi in the future. As it was already written in the previous chapter, there are even paints, primers, etc. with the addition of special components that keep the treated surfaces from fungus.

- Carry out a set of works to drain and waterproof the basement in order to protect against melt and groundwater. This is also true in apartments, in particular on balconies, with insulation.

- On the same balconies, if they have high humidity, and if possible, it is advisable to install a heating system.

- If you feel the taste of mold in your mouth after brushing your teeth, then your toothbrush is a breeding ground for fungus, do not delay replacing it.

- Be sure to wash your hands after placing the street to reduce the spread of fungal spores.

- Throw away food that is moldy by taking it outside.

Mold video (documentary)

Discuss mold and other types of fungus on the forum

Tags: mold, fungus, mold mushrooms, black mold, white mold, efflorescence, mold on the walls, how to get rid of mold, mold removal products, how to remove mold, mold video, remove mold, against mold, mold smell, how to remove mold, mold film , mold photo, home mold, causes of mold, why mold is dangerous, folk remedies, mold prevention, ventilation, ventilation, humidity, mold control, types of mold, mold spots, mold on wallpaper, against fungus, fungus on walls, home fungus, fungus in the apartment

Unfortunately, many managed to get acquainted with mold. But not everyone knows that it is different. Not only colors differ, but also the structure, as well as the effect on the human body. What types of mold exist?

Mold: what is it, why does it appear?

Mold is fungus. The spores of these microorganisms are almost everywhere: they hover in the air, settle on clothes, any surfaces, as well as food. And if such disputes fell into favorable conditions, then they will begin to multiply and develop new territories. Mold can settle on almost any surface, including wood, concrete, brick and other building and finishing materials. Often, fungi get into food and multiply there. The mold has two threads. One of them penetrates into the substance and begins to form a mycelium (vegetative body), the other goes up and contains the resulting spores.

The types of mold are quite numerous, but the causes of the appearance of fungi are the same:

  • Lack of ventilation. If there is a lack of fresh air, then fungi will quickly take root and begin to multiply. That is why they most often live in poorly ventilated areas, such as bathrooms or cellars.
  • Increased humidity. This condition for the reproduction of fungi is ideal. And if the humidity rises to 90-95%, then mold immediately begins to develop. In a humid room, condensation forms on the surfaces, which provokes the formation of mold.
  • Temperature fluctuations. They lead to condensation.
  • Bad sealing. In this case, moisture penetrates into the room (or into the food packaging, for example).

What is mold?

There are different types of mold. It may vary in color and structure. If you look at the pictures, you can see the most unusual images. And when viewed under a microscope, you can see the interweaving of threads and spores. In the photo, the fungi look like small specks or rather large clusters with a fluffy surface. Each type of fungus is amazing.

black mold

Black mold is often what scares people the most, as it is more visible on many surfaces. In the photo, it looks like black spots of small sizes. Black mold is not one specific species, but a whole group, since various strains at different stages of development can acquire this color. Also, the shade may depend on the surface on which the fungus has settled.

So, black mold includes the following strains:

Thus, black mold can indeed be considered the most common and one of the most dangerous.

green mold

Green mold is a genus of fungi from the Ascomycetes group. It can also be considered very common. Its spores are most often found in soil or in a wide variety of organic materials, such as compost. In the photo, the fungi look like a light green coating with an uneven surface. Often, green mold affects vegetables and fruits, as well as other products (especially sour-milk). It develops quite quickly and almost immediately penetrates deep into the tissues, thereby infecting them completely. That is why eating spoiled fruits can lead to serious poisoning. Often, green mold settles on building materials (especially on wood) and begins to gradually destroy them.

Green mold is quite whimsical, as it loves high humidity, as well as relative heat. The optimum temperature for reproduction is 20-25 degrees.

Pink mold is represented by the trichocetium genus, which includes about 70 various kinds fungi. In the photo, it looks like a light pink matte or slightly fluffy coating. Most often, such fungi are harmless and safe for humans, but still you should not eat them. This species in most cases affects plant residues, as well as decomposition or decay products, for example, rotting plants, spoiled vegetables or fruits, improperly stored cereals and grains.

White mold is also common, but generally less of a concern. Indeed, it is less dangerous. Most often, white mold affects the soil (including the one in which houseplants live), trees, various plants, as well as cheese and bread. Some species are used to make noble cheeses. In the photo, the fungi look like a white coating with many weaves of the finest threads.

White mold is represented by the following strains:

Blue mold is a blue fungus that most often infects wood. Some species are used to make cheese. In the photo, such fungi look like a blue coating. Blue mold is not dangerous to humans.

gray mold

Gray mold belongs to saprophytic microfungi and is very dangerous for humans. It looks like a gray patch. It is worth noting that gray mold can affect any surface and materials, as well as food.

How to fight?

To get rid of mold, you need to eliminate the causes of its occurrence, that is, reduce humidity and ensure normal air circulation in the room. To remove plaque, use special means - antiseptics. It is important to remove the entire mold, probably with part of the finishing or building materials. Spoiled food is best thrown away.

Now you are familiar with all types of mold.
http://www.youtube.com/watch?v=nV5NplwPPww

Mold fungi form characteristic plaques, or mold, on the surface of the soil, plant residues, various food products - bread, boiled vegetables, fruits. Mold fungi include white mold mucor (about \ (60 \) species) and gray molds (\ (250 \) species).

mukor mushroom

If the bread lies for several days in a warm, humid place, a white fluffy coating appears on it, which darkens after a while. This is a fungus-saprophyte mukor.

Mukor propagates by fragments of mycelium or spores.. Round heads ( sporangia) with disputes. When the spores mature, the heads burst and the spores are dispersed by the wind. Once in favorable conditions, they germinate and form new mycelium mucor.

Some types of mukor (Chinese mukor) are used in Asian countries as a leaven in the manufacture of food, such as soy cheese.

Mucor fungi are also used to control insect pests.

Often, mucor grows on feed, food, causing spoilage - mold. Sometimes mucor causes diseases in animals and humans.

fungus penicillium

Other mold fungi also settle on food products and on the soil. One of them is penicillium.

The penicillium mycelium, unlike the mycelium mukor, consists of branching filaments separated by partitions into cells.

controversy penicilla are not located in the heads, like in mucor, but at the ends of some threads of the mycelium in small tassels.

Penicillium has been of great help to mankind in the development of medicine. At the beginning \(XX\) c. scientists have found that pathogenic bacteria die in the presence of green mold - penicillium.

Since then, the drug produced from this fungus - penicillin - has become the most important antibiotic, the use of which has saved millions. human lives. It still helps to successfully fight many infectious diseases.

Unicellular and mold fungi are of particular importance in soil formation, participating in the mineralization organic matter and in the formation of humus. They can even process fiber (cellulose cell wall) of plants. The number of such fungi in the soil is huge, so their role in nature is great. They process organic matter present in the soil, ensuring its fertility.

The kingdom of mushrooms is one of the most unusual and impressive in the world of wildlife. The diversity of these organisms is really impressive, and their properties are worthy of careful study. People encounter some of their species every day, without even thinking about the fact that these are mushrooms. It is on such varieties that it is worth dwelling in more detail.

What are mushrooms?

This kingdom has a complex classification. Most people understand only one type of mushrooms, the main one is hat. It includes both edible and poisonous options - champignons, truffles, mushrooms, chanterelles, fly agarics, grebes and many others.

Another, even more interesting species are fungi. They are microscopic in size, due to which the fruiting bodies and mycelium are almost impossible to notice with the naked eye. But in general, it is not at all difficult to see them - just leave a piece of bread in a humid place, and soon a familiar fluffy coating will appear on it. These are mold fungi, namely saprophytes, inedible appearance, often spreading over fruits, vegetables, soil and walls of damp dark rooms.

The third type is yeast. They have been known to man for a long time and are as common as mold fungi. For example, it is to them that people owe the existence of bread, beer, wine and kvass. Molds and yeast reproduce equally well in the everyday human environment, but, unlike the former, which prefer dampness and twilight, the latter need sugar. But there is one thing in common - yeast is also impossible to see in detail without a microscope. To date, a person knows 1500 of their varieties.

yeast mushrooms

This species differs from all others in that it has lost the mycelial structure classic for the kingdom. Yeast lives in a liquid or semi-liquid medium filled with organic matter. They exist as dividing or budding cells. This structure allows them to have the highest possible metabolic rate, so they can grow and multiply quickly. Although molds and yeasts seem similar due to their microscopic size, the former still have mycelium and all the characteristic features, while the latter are one cell. The history of the origin of the name of this variety is interesting. The word "yeast" refers to the trembling that can be seen in fermented wort or rising dough.

Features of mold fungi

This variety retains most of the properties of cap species. However, they are microscopic in size. Mold fungi form the thinnest branched mycelium, from which large fruiting bodies are not separated. They were the first inhabitants of the planet Earth, on which they appeared more than two hundred million years ago. The mycelium of the mold fungus develops in almost all conditions in nature, regardless of the availability of food and the characteristics of the habitat. Huge colonies instantly appear in the presence of humidity and a sufficiently high temperature.

Mold species are very numerous, but they have common features- the basis is the mycelium, and thin branching threads are placed directly inside the affected surface. Unlike yeast, they reproduce sexually or vegetatively. The mold cell does not make up its entire body. However, this does not prevent them from spreading at a tremendous speed.

The most famous fungi

Some of the representatives of the kingdom are more important to humanity than others. These are penicillium molds, which are green spots that grow on plant substrates and common foods. They produce an antibiotic called penicillin, which was the world's first antibacterial drug. His invention changed the world of medicine. Both molds and bacteria can be harmful to human health. But a species called penicillium can save lives, which has earned its widest fame.

Phycomycetes class

One of the most common species are Phycomycetes, or mucor molds. There are more than three hundred varieties in this family. The three most common are Mucor, Thamnidium and Rhizopus. The structure of mold fungi mukor differs in that their mycelium often consists of a single branched cell. Aerial spherical hyphae filled with many spores depart from it. The spread of mucoral occurs easily and quickly on many types of substrate, with the exception of dairy products, and stops only at temperatures below -8 degrees Celsius.

Ascomycetes class

It is to this family that penicillium fungi belong, as well as some others, for example, the genus Aspergillus. Otherwise, this class is called marsupials. While mucor molds form a primitive unicellular mycelium, ascomycetes differ more complex structure, which quickly forms separate colonies that grow along the substrate. Spores are instantly formed on it, to which the mold owes its fluffy appearance of a grayish-green color. When studied under a microscope, the reasons for the name become obvious - the structure of molds includes long chains of conidia containing spores, which form a brush or bag. Ideal conditions for development are dampness and poor ventilation at temperatures close to 0 degrees Celsius.

Difference Aspergillus from Penicillum

Found in the same family, these molds are similar in appearance. They have a colorless mycelium with colored spherical conidia, as a rule, they are distinguished by a grayish-blue or gray-green tint, less often with a yellow undertone. However, the role of aspergillus molds is markedly different. While penicillin is an important ingredient in medicines, the penicillin-related form contains substances that cause spoilage in dairy or meat products.

imperfect mushrooms

This class has not been studied as extensively as those described above. Imperfect mold species reproduce by a method other than sexual reproduction, not known in detail. They are distinguished by septate mycelium with grape-like spores of dark color. Because of this, the defeat of such mushrooms forms black velvety spots. Such mold develops well at low temperatures and is characterized by a large affected area - when it appears on meat, it penetrates deep into the muscle tissue. It is these fungi that can lead to internal mold, spoil butter, cheese, egg products.

milk mold

Mushrooms of the variety Oidium lactis resemble yeast in their structure. They have a white septate mycelium with separated spores in the form of single cells. The nutrition of molds of this species includes a variety of dairy products. Their appearance is manifested in the form of a fluffy white coating, which can cover the surface of sour cream, curdled milk or cottage cheese. Mold reduces their acidity, causing the product to deteriorate. Some scientists attribute them to yeast due to the simplicity of cell chains and felt-like mycelium.

Mold that grows in the refrigerator

Several varieties of fungi can affect products that are stored at a sufficiently low temperature. First of all, this is Botrytis, which is distinguished by a creeping felt-like mycelium, with colorless conidia appearing in bunches. Molds also include those that are distinguished by brown or olive conidiophores. A similar species develops in the refrigerator at temperatures below 5 degrees Celsius and affects a variety of products. Another dangerous species to eat is Alternaria. These include mushrooms with pear-shaped or pointed conidia of brown or olive color. Such mold can infect not only chilled, but also frozen meat, as well as butter and other food products.

Thomas class

These molds differ from all others in their original structure. They do not form an external mycelium and most often develop inside the substrate, which is undergoing a decay process. To reproduce, Phoma molds use short conidiophores with intertwined hyphae surrounding them like a shell.

How does mold affect the human body?

Not all types of mushrooms are as useful for humanity as penicillium. More often, the situation is quite the opposite, and the appearance of mold is an unkind sign. First of all, its spores have a very negative effect on the mucous membranes of the body, causing immune reactions. This is one of the strongest allergens, and people with certain problems in this area are guaranteed to be uncomfortable at the slightest contact with mold. And it's not just a short-term reaction - over time, everything can end in serious diseases. In houses affected by molds, eight out of ten tenants develop asthma. The number is very impressive. And this is not all possible problems.

If such a problem arises, it is necessary to think about ways to destroy mushrooms as soon as possible. To do this, you should use a special antiseptic, which can be purchased at a building materials store. It is necessary to work with it as carefully as possible, having studied the instructions for use. In addition, before starting the fight against mold, it is worth examining how deeply the surface is affected. Sometimes it is better to throw away an infected item. If the defeat is not so large-scale, you can proceed to action. First of all, pay attention to the antiseptic primer. It will not only kill the mold, but also prevent its reappearance. Using such a tool is quite simple, most often you do not even need to dilute it with water. It is only recommended to clean the surface before treatment.

If opportunities or desires seek special remedy no, it is worth turning to home methods. For example, bleach might be a great option. The sodium hypochlorite contained in it kills not only mold, but also its spores. Bleach is ideal for when you need to clean bathroom tiles, floors or glass. But for other items, it can be dangerous - many things lose color or deteriorate from such processing. In addition, bleach is quite toxic, so you should only use it in a well-ventilated room, armed with protective rubber gloves.

Vinegar is less dangerous in such cases. It is not so toxic, so it can be used without fear. It is worth using vinegar with a spray bottle or by wetting a rag in it and wiping the surface affected by mold.

For those who do not have such a tool in their arsenal, hydrogen peroxide is suitable. It can be bought at any pharmacy, it is not dangerous to health and does not have a pungent odor. Peroxide can kill mold on a wide variety of surfaces, but be aware of its bleaching effect, which can be harmful to fabrics or paints.

For hard surfaces like tiles and glass, ammonia is also suitable. It is enough to mix it with water in equal proportions and spray the mixture over the entire infected area, and rinse it with water after a few hours.

The safest remedy is baking soda. It will not harm family members or pets. To combat mold, a teaspoon of soda is dissolved in a glass of water, after which the affected surfaces can be sprayed with the mixture. It is not necessary to wash off the solution - it will be a prophylactic.

Fungi constitute an extensive group of lower spore-bearing plant organisms. They are devoid of chlorophyll and therefore are not capable of synthesizing organic substances from carbon dioxide and water, but need ready-made organic compounds for their development.

Some types of mushrooms are of great industrial importance. They are used in the production of enzymes, vitamins, antibiotics, organic acids, used in the production of fodder (protein) yeast, in the manufacture of certain types of cheese (Roquefort, snack), soy sauces, etc. Yeast, widely used in life, also belongs to mushrooms.

mold mushrooms

Structure. The body of fungi is composed of a large number colorless, microscopically small, branched and intertwining thin filaments called hyphae. Under a microscope, hyphae are seen as tubular fibers. The thickness of the hyphae ranges from 1 to 15 µm. When developing on a nutrient medium, hyphae form radiating from the center, first small, and then more and more abundant, easily visible to the naked eye, clusters, called mycelium or mycelium. The lower part of the developing mycelium spreads along the surface of the substrate and grows into it, penetrating it in all directions, and the upper part - the spore-forming part - rises above the substrate into the air as it grows, forming delicate cobweb fluffy cotton-like or velvety plaques. The vegetative part of the mycelium is usually whitish in color, and the spore-forming part, when fruiting bodies develop on it, acquires a different color depending on the type of fungus - white, yellow-brown, brown-black, black, brown or green, etc. In some types of mold fungi, hyphae do not have no partitions and mycelium is one giant overgrown cell. Such fungi are unicellular, and their mycelium is called non-septate. In other types of fungi, the hyphae are separated by septa into individual cells. In this case, the mycelium of the fungus is called septate or multicellular. Hyphae have a thin shell, colorless protoplasm (cytoplasm). Vacuoles and various inclusions in the form of reserve nutrients (glycogen, fat, volutin) are observed in the cytoplasm. The shell of the hyphae consists of carbohydrates close to cellulose, nitrogenous substances similar to chitin, and pectin substances.

Unlike bacteria, fungal cells contain a distinct isolated (differentiated) nucleus, and sometimes several nuclei. The multinucleation of cells among fungi is very widespread. Thus, fungi are more complex organisms than bacteria.

Reproduction. Significant differences are observed between different types of fungi. But they do not consist in the structure of the mycelium, but in the structure of the organs of sporulation and the methods of reproduction characteristic of each type of fungus. Mushrooms reproduce both asexually (vegetatively) and sexually; and in the same fungus both sexual and asexual reproduction can be observed. Asexual reproduction of fungi is more characteristic. There are fungi in which the sexual process is not found at all.

Mushrooms form numerous spores that serve for reproduction purposes. Sporulation occurs at a certain stage in the development of the mycelium, both vegetatively and after the preceding sexual process. Disputes arise in special organs of sporulation (or fruiting). These organs in fungi are so typical that they are an important feature for recognizing their species.

Asexual, or vegetative, reproduction. 1. Simple division. Each piece of mycelium, once in favorable conditions, begins to increase in size, grows, branches, giving rise to a new organism. In some fungi, such as the milk mold Oidium lactis, hyphae can break up into separate short cylindrical, spherical or ellipsoidal cells - oidia. The division of hyphae into oidia begins at their ends and can lead to the disintegration of the entire mycelium. From each oidia, a new mycelium of the fungus can develop.

2. The formation of special fruiting organs containing spores or conidia. At a certain stage of vegetative development in some fungi, the cytoplasm of hyphae begins to assemble into separate lumps. Each lump is covered with a new, usually thick and dark-colored shell, forming the so-called chlamydospore. Hyphae become like chains or necklaces. Sometimes chlamydospores occur at the ends of special hyphae. Chlamydospores are, apparently, the dormant stage of the fungus and tolerate adverse conditions more easily than vegetative hyphae and oidia.

In unicellular fungi, from the mycelium that has reached a certain maturity, thicker than usual fruit-bearing hyphae, sporangiophores, begin to grow upward (Fig. 6). The end of the sporangiophore thickens, turning into a spherical head - sporangium. At the same time, the sporangiophore grows inside the sporangium in the form of a column or club-shaped columela. The multinucleated cytoplasm of the sporangium, as it matures, begins to disintegrate into a huge number of unicellular and usually immobile endospores (internal spores, or sporangiospores), separated from each other by membranes. When the spores mature, the cytoplasm remaining between them swells, the sporangium bursts, the spores spill out and are easily carried by wind and insects. The maturing sporangium usually becomes dark (more often black). Sporangiophores grow either one at a time or in bunches, but do not intertwine with each other.

In some fungi, sporangiospores are mobile, they look like bare cells equipped with flagella. Motile spores are called zoospores. The formation of a fruiting body in the form of a sporangium with immobile sporangiospores is characteristic of mucor or capitate mold, a typical representative of which is Mucor mucedo, or black mold (Fig. 6).

Getting into the depth of a liquid sugar-containing substrate, with a lack of oxygen, the mycelium of some mucor fungi breaks up into separate oblong or oval yeast-like cells, called mucor yeasts (Fig. 7).

In mushrooms with septate mycelium, the fruiting filaments extending upward from the maturing mycelium are called conidiophores. Conidiophores do not form heads (sporangia). They either branch in the form of brushes, or swell slightly, forming an oval or rounded extension. On the tassel or extension, as it matures, short cylindrical cells, sterigmata, are laced off. Sometimes even shorter sterigmata of the second order appear on them, which, in turn, lace off rounded bodies painted in various colors - conidia (exospores). If the sterigmata are located on a slightly expanded part of the conidiophore, and the lacing conidia fan out from them in all directions, resembling jets of water pouring out of a watering can, then the fungi are called watering mold (Aspergillus) (Fig. 8). At mold Penicillium(or brush) the end of the unthickened conidiophore bifurcates fork-like into sterigmata of the first order and sterigmata of the second order. On sterigmata of the second order, parallel chains of conidia are laced (Fig. 9), which gives the fruiting organ the appearance of a brush or panicle. In the initial stage of sporulation, Aspergillus is very similar to young Mucor with a colorless head. But with age, Aspergillus heads become "hairy", while Mucor's heads are always smooth.

Aspergillus and penicillium fungi are involved in the mineralization of various organic substances. In industry, the fungus Aspergillus niger is used to produce citric acid, PenicilHum notatum and Penicillium chrisogenum to produce the antibiotic penicillin. Penicillium roquefortii plays important role in the maturation of a special kind of cheese (roquefort).

Nearly half of all molds found in nature belong to the genus Penicillium. Molds grow in abundance on the walls of damp rooms, on the surface of mechanically damaged and long-stored vegetables and fruits, on jam, on poorly stored dairy products, compotes and other food products.

Conidiophores in certain types of fungi grow in groups. When conidiophores are intertwined into one bundle, an accumulation is formed, called coremia. A group of short conidiophores located on a dense plexus of hyphae is called a bed; a bundle of conidiophores surrounded by a sheath of intertwined hyphae is called a pycnidia (Fig. 10).

Sexual reproduction of fungi. During sexual reproduction of fungi, sporulation is preceded by a sexual process - the fusion of the contents of two cells (copulation) or the fusion of nuclei in a binuclear cell. Copulation (real sexual process) is observed in unicellular fungi. In multicellular fungi, nuclei fuse in the resulting binuclear cell.

1. Copulating cells in unicellular fungi can be exactly the same (isogamous). The hyphae of the same mycelium or different mycelia come into contact. The fusion of identical cells is called isogamy. When two cells, different in appearance or age, merge, the sexual process is called heterogamy.

By the time of maturation of the mycelium, swollen processes appear on the hyphae lying close to each other, separated from the main hypha by a septum. These processes then come into contact, in which there is a gradual dissolution of the membranes of the swelling at the point of contact and the subsequent merging of the contents of both cells in one common channel. The emerging binuclear cell is covered with a multi-layered and gradually darkening shell and, finally, turns into a spore. The spore that arose during the copulation of completely identical cells was called the zygote, or zygospore (Fig. 11, c).

In heterogamous copulation, a small (male) cell (antheridium) passes into a larger (female) cell (oogonium) without fusion. The resulting binuclear cell is called an oospore.

2. In multicellular fungi, typical fruiting organs develop from a cell formed after the fusion of nuclei:

a) basidia (Fig. 11, b), having the form of oblong, sac-like elongated cells, passing into a hypha at the base, perform a function similar to that of a conidiophore. At the free end of the basidium, four processes grow - sterigmata. Each sterigma produces only one basidiospore. Basidia sometimes develop in a continuous layer (hymenium) in special fruiting bodies, which in everyday life are called hat mushrooms (fly agaric, russula, white mushroom, etc.);

b) bags (asci) (Fig. 11, a) outwardly represent elongated cells. A strictly defined number of ascospores (from 2 to 12) is formed inside the bags. Bags arise either directly on the mycelium without the formation of a fruiting body, or in special fruiting bodies (apotheciums or perethecia). In the first case, the mushrooms are called golomarsupials, in the second case, fruiting marsupials. Yeasts are technically the most important representatives of the fungi.

Aspergillus and penicillium molds belong to the fruiting fungi. In most cases, each type of fungus is characterized by one of the sexual (higher) forms of fruiting and some kind of asexual (vegetative) - the formation of conidia, oidia, etc. Mushrooms, in the development cycle of which a sexual process is observed, are called perfect.

However, there are fungi that sexual reproduction not fixed. These fungi are classified as imperfect fungi. Imperfect fungi include genera: Fusarium (Fusarium), Botrytis (Botrytis), Alternaria (Alternaria), Cladosporium (Cladosporium) and many others. Imperfect mushrooms in most cases are the causative agents of spoilage various materials And food products. So, Fusarium causes a disease of potatoes, called dry rot, botrytis - gray rot of fruits and vegetables; Alternaria causes damage to root crops (carrots, parsley, etc.); cladosporium during its development forms black spots on the surface of food products (butter, meat, eggs, etc.). Certain types of Cladosporium cause damage to cotton fiber.

In addition to various methods of sexual and vegetative propagation, most fungi, when adverse conditions occur, are able to move into a resting stage, forming the so-called sclerotia - solid formations, nodules, lumps of tightly intertwined hyphae. They are of various sizes and shapes, dark on the outside, and completely white on the inside, do not contain any spores.

Once in favorable conditions, sclerotia germinate into certain fruiting organs, depending on the type of fungus. The most characteristic sclerotia forms fruit rot - Monilia fructigena, which causes spoilage of pome fruits (apples, pears), and gray rot - Monilia cinerea, which affects stone fruits (cherries, plums, apricots, peaches).

Yeast

Yeast, as already mentioned, belong to the fungi. They develop well in fruit and berry juices, in sugar-containing media, they are found on the surface of fruits, berries, vegetables, in fruit products (comotes, jam, marmalade, marmalade), as well as in marinades, tomato products, etc. Yeasts are unicellular immobile microorganisms. Yeast cells are much larger than bacterial cells. The length of the yeast cell in some cases reaches 6-10 microns and even 12-18 microns, the width varies from 4 to 8 microns.

Yeast cell shape(Fig. 12). Most often there are oval-elliptical and spherical yeast cells, less often - cylindrical, lemon-shaped, ovoid, sausage-shaped. The shape and size of cells can vary depending on the conditions of the environment in which they develop. Yeast cells have a dense double-circuit membrane. Inside it is the cytoplasm. Yeast cells, unlike bacteria, have a distinct (differentiated) nucleus.

In young yeast cells, the cytoplasm is bluish-green in color with a soft foamy structure. As cells develop, the cytoplasm changes, and vacuoles filled with cell sap appear in the cells. Grains of glycogen, volutin, fat droplets can be included in the cytoplasm of yeast cells as reserve nutrients. Some varieties of yeast accumulate so much fat that they are used for industrial purposes.

Yeast is an excellent producer of protein and vitamins (eg vitamin B12). Feed yeast is currently being produced from treacle stillage, from the waste of the alcohol industry, the use of which in fattening animals significantly increases the weight gain, reduces their incidence, etc. Yeast reproduces mainly by budding, less often with the help of spores, and even more rarely by simple division.

budding(Fig. 13). During budding, a tubercle, a bud, appears on the surface of the yeast cell. Part of the cytoplasm and half of the nucleus passes into it from the mother cell. The kidney grows, increases in size. At the site of its connection with the mother cell, a constriction occurs. Under favorable conditions, after about 2 hours, the young cell, having reached half or the full size of the mother cell, completely separates from it. However, in some types of yeast, the daughter cells remain connected to the mother cell and each of the cells can give rise to new buds. Such an accumulation of yeast cells - budding growths - resembles the mycelium of mold fungi; they are called false mycelium. Usually, the false mycelium is formed by membranous yeasts.

Sporulation. Unlike bacteria, from 2 to 4, and sometimes 8 or even 12 spores, are formed in a yeast cell. Therefore, the process of sporulation in yeast is considered as one of the methods of reproduction. Spores in yeast are formed with a lack of nutrients and always with the access of atmospheric oxygen. If the yeast is grown in highly nutritious media with frequent reseeding, they bud all the time and do not go into the sporulation stage. Only in "hungry environments" - with a lack of nutrients - does sporulation occur. The nucleus of a sporulating yeast cell without prior fertilization (copulation) - parthenogenetically - begins to divide into as many parts as a spore is formed in this type of yeast. Each particle of the nucleus is surrounded by a small amount of cytoplasm and each ascospore is covered with its own membrane. The shell of the mother cell remains in the form of a bag (asca). In most cases, yeast spores are round or oval, and only in some species have a peculiar shape (for example, hat-shaped, etc.). Yeast spores are more resistant to harmful effects than vegetative cells.

In some yeast species, simple division is observed, similar to the division of bacterial cells. Finally, there are species in which reproduction begins according to the type of budding, and ends according to the type of division. The method of reproduction is hallmark when determining the genus - yeast. Yeast that can reproduce by budding and spores is called true yeast. Some yeasts are not capable of sporulation and reproduce only by budding. Such yeast is called false.

Yeasts are able to convert sugar into alcohol and carbon dioxide, which is why they are called sugar fungi (saccharomycetes). By origin, yeasts are divided into cultivated and wild.

TO cultural include such yeasts that, as a result of many years of use in production, have acquired certain valuable properties. Most importance in industry, the yeasts Saccharomyces cerevisiae and Saccharomyces ellipsoideus have. The species Saccharomyces cerevisiae combines numerous races used in the production of alcohol, baking, and brewing.

The species Saccharomyces ellipsoideus includes races of yeast used in winemaking.

Races separate varieties of yeast are called, belonging to one or another species and differing from each other in some characteristics. For example, yeast races used in winemaking should impart a specific aroma (bouquet) to various wines.

The yeast used in the production of alcohol, as well as in bread baking, is the so-called top yeast. Fermentation with the participation of such yeast proceeds rapidly, at temperatures of 20-28 ° C. The released carbon dioxide contributes to the formation of a large amount of foam and brings the yeast to the upper layers of the fermenting substrate. The sedimentation of the yeast to the bottom and the clarification of the liquid occurs after the end of fermentation. Alcohol yeast is highly resistant to alcohol, baker's yeast is characterized by a high reproduction rate and rapid uniform release of carbon dioxide, which contributes to good loosening of the dough.

In brewing and winemaking, the so-called grassroots yeast is more often used. Fermentation with this yeast proceeds smoothly, at lower temperatures, grassroots yeast remains at the bottom, which contributes to a good clarification of wine and beer.

TO wild yeasts include lemon-shaped (Hansenlaspora apiculata), mycoderma (Mycoderma), torula (Torula), etc. Lemon-shaped (or pointed) yeasts are often found in nature, they are found on the skin of all sweet fruits, berries, including grapes, they are pests winemaking. These yeasts tolerate no more than 6-7% vol. alcohol, and their metabolic products adversely affect the taste and bouquet (aroma) of wine.

Torula amarae causes rancidity in milk, cheese, butter. These yeasts have rounded cells and are capable of producing pink and black pigments, which is why they are called “pink” or “black” yeasts.

Yeasts of the genus Mycoderma have elongated cells (Fig. 14). From the very beginning of development on liquid nutrient media, they form a whitish-gray wrinkled film that creeps up along the walls of the vessel. These yeasts are not capable of fermentation and are called filmy yeasts. In nature, yeasts of the genus Mycoderma are widely distributed. They cause spoilage of various products. So, Mycoderma vini develops on wine, Mycoderma cerevisiae develops on beer. Oxidizing alcohol to water and carbon dioxide, these yeasts cause the appearance of an unpleasant taste and smell in wine and beer.

Developing on the surface of fermented foods (sauerkraut, cucumbers, tomatoes, etc.), Mycoderma yeast causes the oxidation of not only alcohol, but also lactic acid, which is a preservative in fermented vegetables. Mycoderma develops especially vigorously at elevated temperatures. The decrease in acidity opens up the possibility for the development of putrefactive microbes. As a result, the quality of sauerkraut is sharply reduced, an unpleasant smell and taste appear, the texture of vegetables becomes flabby, mucus forms, and sauerkraut darkens.

Very close to yeast are the so-called yeast-like organisms, which are widely distributed in nature. These include the fungi Oidium, Monilia, Endomyces. Oidium lactis - milk mold (Fig. 15) - has a septate white mycelium that can reproduce by division. However, along with the mycelium, oidium produces oval cells that reproduce by budding, like ordinary yeast. Oidium spores look like rectangular or slightly oval cells, shaped like yeast. Developing in the form of a velvety white coating on the surface of dairy products, cucumber, cabbage pickles, milk mold acts like mycoderma, causing the oxidation of lactic acid to water and carbon dioxide. By reducing acidity and thereby opening up the possibility for the development of putrefactive microbes in fermentations, Oidium lactis contributes to the spoilage of these food products.