Genus Aspergillus (Aspergillus). What danger does black mold pose to humans Aspergillosis fungus

The mold that has appeared in the house can not only spoil appearance walls, covering them with an ugly black coating, but also seriously undermine human health. Its spores can provoke the development of benign and malignant tumors, allergies, dermatitis and other dangerous pathologies. Therefore, it is important to know why mold is dangerous, how to get rid of it and prevent its occurrence.

Varieties

Black mold plaque is a colony of microscopic fungi. Most often these are the following types.

Aspergillus niger (Aspergillus black)

This saprophytic fungus develops on the surface of damp walls and ceilings, on sheets of old books, in pots of indoor plants, on tile joints in rooms with high humidity (bathrooms, kitchens, baths, swimming pools), in washing machines, air conditioners, air humidifiers.

The spores of this fungus are easily spread throughout the room with the help of air movement, enter the human body through the respiratory tract, and settle on food and household items. They cause:

• rhinitis;
• bronchial asthma;
• pneumonia;
• myocarditis;
• meningitis;
• the formation of papillomas and even cancer cells.

When a large number of spores are inhaled, a person may develop intoxication phenomena, which, in the case of a weakened immune system, can be fatal.

A specific disease caused by fungi Aspergillus niger, is pulmonary aspergilloma. Penetrating through the nasopharynx into the bronchi, bronchioles and alveoli, the spores begin to actively develop, releasing the strongest toxins, leading to the formation of necrotic foci. Gradually, the parenchymal tissue ceases to perform its function, asphyxia and death occur.

Aspergillus fumigatus (Smoky Aspergillus)

More often it affects the fruits of vegetables and fruits that have mechanical damage. If the grain was affected by this type of fungus, then a fluffy black coating very quickly forms on bakery products. The danger lies in the fact that the toxin it releases is a strong allergen that causes the destruction of red blood cells and suppresses the production of immune cells.

Alternaria tenuis (Alternaria alternata)

It is a fungus that forms black colonies on walls, food and soil. The toxin released during its vital activity can cause attacks of bronchial asthma and dermatitis.

What encourages fungus to grow

Understanding how dangerous black mold is, it is necessary to take all measures to prevent its appearance in the house. Therefore, it is worth knowing the ways in which pathogenic fungi enter the human home.

Optimal conditions are temperature +18…+25°C with humidity over 70%. Poor ventilation also contributes to this. These are factors that can be eliminated on your own avoiding large material costs. But there are reasons for the appearance of mold, which some people do not even know about. And they are associated with the use of new construction and finishing materials, as well as non-compliance with the rules for their installation.

Plastic windows and doors

On the one hand, this very convenient invention makes it possible to avoid heat losses in the building, minimizes installation, maintenance and restoration costs, and ensures a certain safety of residents. But, on the other hand, their improper operation can lead to the appearance of spores of pathogenic fungi.

The fact is that such windows disrupt the air circulation in the room, provoking the formation of high humidity. This can be avoided by regular ventilation, which should be mandatory even in the cold season.

The second reason may be the formation of condensation on the glass surface. This is due to the wrong selection of the number of glasses or air chambers in a double-glazed window, with poor product quality or illiterate installation.

Application of drywall

This building material is very convenient for leveling walls, ceilings and erecting partitions. Affordability and ease of use make it quite popular with builders and people involved in repairs. But at the same time, many do not take into account the ability of this material to absorb moisture well and keep it inside for a long time.

Therefore, all installation technologies and the drying time of the mixtures must be clearly observed. In such a room, microclimate parameters should be created that prevent the appearance of black mold.

If the building is expected to have an increased level of humidity, then antifungal components should be added to the solutions.

Poor ventilation

The layout of apartments and houses often does not provide for the presence of windows in the bathrooms, and natural exhaust ducts cannot cope with a large number of humid air formed during the adoption of water procedures or drying clothes. In this case, it is advisable to install forced ventilation. It will quickly solve this problem and prevent the development of mold microflora, which, with humid warm air, quickly penetrates the human body, having a negative impact on its health.

Damp exterior walls and basements

Clogged drainpipes or their absence leads to frequent wetting of walls and corner parts of buildings. This can cause mold to appear on the facade of the building, which will eventually grow inside the premises. This may be due to the presence of cracks in the masonry.

Damp basements can also be breeding grounds for mold, whose spores can quickly spread through the ventilation system throughout the building.

Mold can get into the house with food or indoor plants. Therefore, pieces of bread, cheese, cereals, vegetables and fruits affected by fungi must be carefully packed in a plastic bag and removed from the premises. Eating such food can cause serious harm to health.

Control measures

Having realized how dangerous mold is to health, and finding it in your home, you should take urgent measures to eliminate it.

by the most in an efficient way is the treatment of the room with a UV lamp. Ultraviolet rays completely destroy fungal spores. For the period of turning on the device, all fresh flowers must be taken out of the room and pets must be removed. We must not forget about the aquarium with fish.

Other destruction methods include:

1. Removing the source of mold from the premises. It can be wallpaper, putty, affected textiles.
2. Adding antiseptics and special antifungal agents to building and finishing mixtures. Particular attention should be paid to grouting tile joints in the bathroom and kitchen.
3. Treatment of affected areas with industrial products, as well as vinegar, soda, bleach solution, hydrogen peroxide or borax.

Remember - it is impossible to leave lesions in an apartment or house untreated. The danger of mold has been proven, so you should not put your health and the health of your children at risk.

Aspergillosis is a disease that is caused by fungi of the Aspergillus family and is characterized by damage to various organs and systems of the body, but the bronchopulmonary system most often suffers.

The disease proceeds, as a rule, chronically with various allergic reactions or toxic manifestations. The causative agent of aspergillosis is quite widespread in environment- they are in the earth, and in water, and in the air, they are able to multiply both in the human body and in animals.

Due to the fact that the first blow takes respiratory system, then the main symptoms of aspergillosis begin to appear just from the respiratory system. Sometimes the fungus enters the body with blood and lymph, quickly spreading to all organs. This type of disease is characterized by a high mortality rate - about 80%.

What it is?

Aspergillosis is a mycosis caused by certain types of fungi such as Aspergillus. Aspergillosis occurs with multiple chronic toxic-allergic manifestations.

If a person falls ill with aspergillosis, then most often he is exposed to infection of the bronchopulmonary system and paranasal sinuses. In some cases, aspergillosis affects the skin, eyes, and central nervous system.

Causes of aspergillosis

The causative agents of the disease belong to the genus Aspergillus, and in human pathology highest value have A. flavus and A. niger, but other species may occur, such as A. nidulans or A. fumigatus. We can say that morphologically, these types of fungi consist of the same type of mycelium, which has a width of 4-6 microns. Aspergillus, as a rule, have a sufficiently high biochemical activity, due to which they can form various enzymes.

The causative agents of pulmonary aspergillosis are widespread in nature. Most often they can be found in hay, flour, soil and grain, as well as in dust. The pathogen usually enters the body with dust through the air. In the aerogenic way, it enters the mucous membranes located on the upper respiratory tract. It is quite possible infection through the skin, which is often changed by another pathological process.

A decrease in the body's immune defense plays a leading role in the development of aspergillosis. This disease can be complicated by various pathological processes of the skin, internal organs and mucous membranes.

Classification

Aspergillosis differs in the localization of its pathological processes:

• bronchopulmonary (including pulmonary aspergillosis);
• aspergillosis of ENT organs;
• aspergillosis of the skin, eyes and bones;
• septic or generalized aspergillosis.

Depending on the ways of infection with fungi, there are several types of aspergillosis:

• endogenous (autoinfection);
• exogenous (airborne or alimentary route of transmission);
• transplacental (vertical routes of infection);

According to statistics, approximately 90 percent of all cases of aspergillosis occur in the primary infection of the respiratory tract, as well as the lungs. About five percent - for infection of the paranasal sinuses. In addition, the involvement of other human organs in the pathological process is diagnosed in almost five percent of people susceptible to infection.

Aspergillosis of the lungs

Aspergillosis of the lungs is very serious diagnosis. Since, due to the development of the disease, which was caused by aspergillus molds, aspergilloma, that is, tumor-like formations that consist of densely woven fungi, begin to form in the lungs of a person. There are also complications such as endocarditis, aspergillus pleurisy, otitis media, meningoencephalitis and others.

However, at any time, aspergilloma can cause a formidable complication - this is pulmonary bleeding, which can be massive and profuse. And in this case, there is no alternative to surgical treatment. Treatment of aspergillosis with conservative methods is possible with fungal lesions of the mucous membranes or skin.

Symptoms of aspergillosis in humans

Since the respiratory system takes the first blow, the main symptoms aspergillosis in humans, they begin to manifest themselves precisely from the side of the respiratory system. In a third of cases, the fungus enters the body with blood and lymph and spreads to all organs. With this type of aspergillosis, the mortality rate is high - about eighty percent. The most rare is cutaneous aspergillosis.

If the fungus settled on the surface and did not penetrate the mucosa, as is the case with tracheobronchitis, aspergilloma, then patients notice the following symptoms: chronic cough with sputum, sometimes with blood with a strained cough. Most often in such cases there are pathologies from the lungs.

In response to the penetration of spores, the body's tissues develop certain inflammatory reactions. The two most common types of inflammation are serous-desquamative and fibro-purulent. With serous-desquamative inflammation, aspergillus causes exfoliation of the epithelium, membranes of the stomach, lungs with the release of exudate (plasma with blood elements). In the second type - fibro-purulent - aspergillus causes the release of exudate with fibrin (clotted blood protein) and a purulent component. The most severe reaction to aspergillosis is the formation of granulomas in the lungs.

Otherwise, aspergillosis gives an acute picture - a dense infiltrate is formed in the lungs, which disintegrates. With the blood flow, infection of other organs also occurs. At the onset of acute aspergillosis, the phenomenon of neutropenia is characteristic, which is expressed in sudden weakness, nosebleeds, fever, severe chills, severe sweating, tachycardia, and a sharp decrease in pressure. In this case, a decrease in neutrophils is found in the blood, which makes it difficult for the body to give an inflammatory response to the focus of aspergillosis. Therefore, with neutropenia, it is often not possible to diagnose aspergillosis - all indicators would seem to be normal. However, doctors know from experience that this can signal the beginning of aspergillosis, so additional studies are prescribed. Most often, aspergillus settle in the sinuses. At the same time, red foci appear, after the decay of tissues, they lose their color, and then turn black. This process is very rapid - it usually spreads to the eye sockets, facial tissues, towards the brain. Typical symptoms in this condition are congestion, pain in the nasopharynx, sinuses, swelling of the mucous membrane. The sinuses are filled with pus, but they do not erupt.

Often, allergic aspergillosis is associated with bronchial asthma. At the same time, patients note asthmatic attacks, eosinophils are increased in the blood, dark areas on an X-ray examination, the presence of antibodies in the serum (galactoman). To clarify the diagnosis, a sputum test is taken. In more than half of patients, aspergillus is found during culture. In this case, a secondary seeding is done to clarify the diagnosis (since conidia could have accidentally entered).

Diagnostics

Aspergillosis in adults requires careful and complex diagnostics, which, first of all, is necessary to identify the variety and severity of the course of such a disease.

The first step in establishing the correct diagnosis is the clinician referred to by the person based on the predominant symptom. The doctor needs:

• get acquainted with the medical history and anamnesis of the patient's life - this may indicate some etiological factors;
• conduct a detailed survey of the patient - to determine the first time of appearance and the degree of intensity of expression of symptoms. This will enable the clinician to determine the severity of the disease;
• perform a thorough physical examination, which, depending on the situation, may include an ophthalmic examination of the eyes, palpation of the anterior wall abdominal cavity, the study of the condition of the skin and nail plates, as well as listening to the lungs with a phonendoscope.

Instrumental diagnosis of aspergillosis includes the implementation of:

• chest x-ray;
• biopsies;
• bronchoscopy;
• spirometry;

Laboratory tests will also differ depending on the nature of the infection. In most cases, they include:

• study of discharge from the nasal sinuses or external auditory canal;
• microscopic examination of feces;
• complete blood count - may indicate the course of an allergic or inflammatory process;
• analysis of sputum released when coughing - to detect particles of aspergillus;
• blood biochemistry;
• scraping from the skin or nail plates;
• imprint from the surface of the cornea;

Such events will help not only to make the correct diagnosis, but also to conduct a differential diagnosis of such an ailment.

Aspergillosis treatment

Regardless of the type of aspergillosis a person has, treatment is a very time-consuming task. Chemotherapy and antibacterial agents do not lead to the expected effect, as well as all the others. known to physicians methods of combating infectious diseases.

For this reason, in last years When aspergillosis is diagnosed, treatment is based on the use of surgical methods. Patients undergo a lobectomy with resection of the affected organs. If the operation was performed by a competent specialist in compliance with all established procedures, the intervention is tolerated without complications and gives good prognosis for the future.

With advanced forms of pulmonary aspergillosis, surgical treatment is used in conjunction with conservative methods. Patients with aspergillosis are prescribed amphotericin B, oxacillin, nystatin, erythromycin, antibiotics of the tetracycline group. At the same time, a person takes vitamins. Also, patients with aspergillosis are recommended general restorative treatment.

When using antimycotic drugs, the amount of antibodies in the blood increases dramatically, but by the end of treatment it returns to normal. If pulmonary aspergillosis leads to lesions of the skin and mucous membranes, antimycotic and anti-inflammatory drugs are recommended for patients.

Forecast and prevention

The most favorable course is observed with aspergillosis of the skin and mucous membranes. Mortality from pulmonary forms of mycosis is 20-35%, and in people with immunodeficiency - up to 50%. The septic form of aspergillosis has a poor prognosis.

Measures to prevent infection with aspergillosis include measures to improve sanitary and hygienic conditions: dust control at work, employees of mills, granaries, vegetable stores, weaving enterprises wearing personal protective equipment (respirators), improving ventilation of workshops and warehouses, regular mycological examination of persons from risk groups.

The invention relates to biotechnology. Strain Aspergillus oryzae RCAM01135 - producer of proteolytic and amylolytic enzymes - has the ability to produce proteolytic and amylolytic enzymes. Deposited in the State Scientific Institution VNIIShM under the registration number RCAM01135. Can be used in the production of various food products (fermented spices, additives, drinks). EFFECT: invention makes it possible to increase the growth rate and intensity of spore formation. 4 tab., 2 pr.

The invention relates to biotechnology, in particular to obtaining a strain - a producer of proteolytic and amylolytic enzymes, and can be used for the hydrolysis of plant and animal substrates in the food industry, fermentation, agriculture.

The filamentous fungus Aspergillus oryzae is known to have wide application in the food industry, as it does not have pathogenic properties. The biosynthesis of proteases and amylases, characteristic of representatives of Aspergillus oryzae, is used, for example, in the manufacture of certain food products (fermented seasonings, fermented drinks) when hydrolysis of proteins and carbohydrates is required (RU 2361914, 2009, RU 2187947, 2002).

Known Aspergillus strain oryzae VKPM F-369, which has the ability to produce a complex of proteases that exhibit maximum activity in the acidic and slightly acidic pH zone, α-amylase. However, the main disadvantage of this strain is the lack of synthesis of accompanying hydrolases, as well as a long period of growth and development of micromycete; the strain intensively produces α-amylase and protease in liquid media only on the fourth or fifth day (SU 1440922, 1988).

Known strain Aspergillus oryzae VKPM F-683, producing a complex of acidic and weakly acidic proteases, β-amylase and associated xylanases, glucanases and cytases. It is known that this strain produces a whole complex of highly active enzymes during submerged cultivation. The resulting enzyme complexes are used in the food industry.

However, the use of the strain is limited due to the insufficiently high growth rate and special requirements for nutrient media, as it grows on media with a solids content of not more than 18% (RU 2070921, 1996).

The objective of the invention is to obtain a strain of Aspergillus oryzae, producing proteases and α-amylase, with a high growth rate, mainly in solid-phase cultivation.

As an invention, a new strain of the micromycete Aspergillus oryzae 37-53, obtained by the method of multi-stage selection and mutagenesis, deposited at the State Scientific Institution All-Russian Research Institute of Agricultural Microbiology in the Departmental Collection of Agricultural Useful Microorganisms of the Russian Agricultural Academy (RCAM) under the registration number RCAM01135 is proposed. The strain is a producer of proteases and α-amylase, has a high growth rate, mainly during solid-phase cultivation, and intense sporulation.

The technical result of the invention is more high speed growth of the proposed strain of Aspergillus oryzae RCAM01135.

In particular, on media with soybean meal, the maxima of protelytic and amylolytic activities appear on the third day of cultivation, and the intensity of sporulation was also the highest on the third day. This allows us to consider the claimed strain as a promising tool for use in the food industry for the processing of agricultural raw materials, such as soybeans, in order to obtain various food flavoring additives, in the fermentation industry, the baking industry.

The Aspergillus oryzae RCAM01135 strain is characterized by the following cultural-morphological and physiological-biochemical features.

Cultural and morphological features:

a) the nature of growth (pubescence, the edge of the colony). The colonies are fluffy, rounded, the edges are even, the mycelium is white, spore-forming, the color of the colony is from olive to dark green. Vegetative mycelium septate, well branched with large swellings, hyphae thickness 6-12 microns; conidia are formed exogenously, the surface of the conidia is smooth, the shape is round, the spore diameter is 5-6 microns; forms conidial heads with single-tiered sterigmata;

b) colony size (at a certain incubation time). On the 3rd day of growth on wort agar, the diameter of the colony was 50×51 mm;

c) aerial mycelium (presence, color, features of sporulation). With abundant sporulation, dark green. White fluffy mycelium 3 mm along the edge of the colony;

d) the color of the substrate mycelium. White;

e) the color of the reverse side of the colony. Light brown;

f) other signs (pigment, exudate, etc.). Pigments are not allocated, exudate is absent;

g) culture changes with aging. The color of the colony darkens with age, becomes brown-green;

h) behavior on other media. On Chapek's medium with glucose: on the 3rd day of growth, the color of the colony is green, the surface is smooth; colony diameter 32×34 mm.

According to studies of the morphological characteristics of the culture, the strain was identified in accordance with the determinant of filamentous fungi (Bilai V.I., Koval E.S. Aspergillus. Key. - Kyiv: Nauk. Dumka, 1988, - 204 p.).

Physiological and biochemical signs

Relationship to oxygen - aerobic. Optimum temperature growth - 28-30°C. The maximum temperature is 50°C. The minimum temperature is 18°C. The optimum pH value for fungus growth is 5.5. The growth of the fungus is noted in the pH range from 2.5 to 10.0.

The fungus uses starch, glucose, sucrose, xylose, maltose, mannitol, glycerol and lactose as a carbon source. Assimilates nitrates, ammonium and amine nitrogen, proteins. The strain is not pathogenic. In the mode of deep and solid-phase cultivation, the ability to synthesize amylolytic and proteolytic enzymes was established.

The strain is stored on agar malt wort 8% CB; environment pH - natural; storage temperature +20-25°C.

Submerged and solid phase cultivation of the Aspergillus oryzae RCAM01135 strain

Deep cultivation of the Aspergillus oryzae 37-53 strain was carried out on various complex natural environments compiled taking into account the physiological needs of the producer. When designing nutrient media, we took into account the fact that starch and proteins are favorable for the synthesis of proteases and α-amylase; therefore, grain raw materials were the main components of the medium. Potassium phosphate was used as a source of phosphorus nutrition for micromycetes. Thus, for deep cultivation of the Aspergillus oryzae RCAM01135 strain, nutrient media of the following composition were used, %:

1. Barley flour - 3.0, wheat bran - 3.0, starch - 2.0, KH 2 PO 4 - 1.5;

2. Wheat flour - 6.0, wheat bran - 2.0, KH 2 PO 4 - 1.5%;

3. Soy flour - 6.0, barley flour - 5.0, KH 2 PO 4 - 1.5;

4. Soy flour - 6.0, wheat bran - 2.0, KH 2 PO 4 - 1.5;

The cultivation of Aspergillus oryzae RCAM01135 strain was carried out in Erlenmeyer flasks with a volume of 750 cm 3 containing 50 cm 3 of sterile nutrient medium, on a circular shaker with a speed of 220 rpm at a temperature of 30°C. The results obtained are presented in table.1.

As can be seen from Table 1, the selected strain of Aspergillus oryzae RCAM01135 on nutrient media containing barley or wheat flour, as well as wheat bran (media No. 1 and 2), showed the ability to synthesize proteases and α-amylase: total proteolytic activity on the 3rd day cultivation amounted to 1.5-1.8 units. PS / cm 3, amylolytic 0.82-1.10 units. AC / cm 3. On media containing soy flour (mediums 3 and 4), the level of activity of synthesized enzymes decreased by 2–3 times.

Solid-phase cultivation of the Aspergillus oryzae RCAM01135 strain was carried out on wheat bran with a moisture content of 52.4% and on soybean meal with a moisture content of 51.8% at a temperature of 30°C under stationary conditions. The results obtained are presented in table.2.

The results of submerged and solid-phase cultivation confirm the biosynthetic ability of the selected Aspergillus oryzae RCAM01135 strain with respect to proteolytic and amylolytic enzymes, which is characteristic of fungi of the Aspergillus oryzae genus.

Thus, the resulting strain develops well on liquid and solid nutrient media, synthesizes proteolytic and amylolytic enzymes, and is identified as the filamentous fungus Aspergillus oryzae.

Cultivation of the strain Aspergillus oryzae RCAM01135 on media with soybean meal

The production of experimental samples of the selected culture Aspergillus oryzae RCAM01135 was carried out on a medium with soybean meal and on soybean meal with the addition of 10% barley with different humidity within 3 days at 30°C (table 3).

Experimental samples of the fungus A.oryzae RCAM01135 were obtained as a result of accelerated growth micromycetes during surface cultivation on soybean meal are enriched in protein, amine nitrogen and can be used for further processing in the production of soybean fermentation products.

The selected strain of Aspergillus oryzae RCAM01135 and the developed experimental samples of the fungus A.oryzae RCAM01135 were studied at the Testing Laboratory for Technochemical Control and Arbitration Methods of Analysis of the State Scientific Institution VNIIPBT of the Russian Agricultural Academy.

The results of tests for the identification of GMIs showed that there are no transgenic sequences in a pure culture of micromycete Aspergillus oryzae RCAM01135 (test protocol dated March 23, 2012).

When analyzing heavy metals in experimental samples fungus A. oryzae RCAM01135, it was found that their content does not exceed the maximum permissible concentrations (report dated April 18, 2012). Table 4 shows the results of the analysis of the content of heavy metals in the substrate - soybean meal and in the surface culture of the fungus A.oryzae RCAM01135. Similar results were obtained in all experimental samples under study.

CLAIM

The Aspergillus oryzae micromycete strain, deposited at the State Scientific Institution VNIISKhM (Departmental Collection of Agricultural Useful Microorganisms - RCAM) under registration number RCAM01135, is a producer of proteolytic and amylolytic enzymes for use in the food industry.

Everyone at least once in his life met black mold in basements, damp corners of the room, on walls, potted plants and old books. The scientific name of this fungus is Aspergillus niger. With a reduced immunity of a person or animal, mold enters the body through the air and can lead to serious illness. In this article, we will tell you what this fungus is and how to prevent infection.

Aspergillus niger are fungi that can take root and grow into a colony when temperature regime over 40⁰С. They occupy a large area in very short term - up to 3 days. The fungus got its name due to the characteristic dark gray and black color, which indicates the maturation of conidia. They are microscopic formations at the top of the conidial head of the fungus.

Morphologically, Aspergillus niger is represented by several strains that live in damp rooms, food products, and even the human body. Thus, the fungus is ubiquitous, except for vacuum and in conditions of complete sterility. Aspergillus particles separated from the mycelium are in open space. Reproduction of the fungus occurs when the spore attaches and goes unnoticed. Its structure consists of 2 thread-like bodies: one is a vegetative formation, and the second gives life to new spores when ripe.

Favorable factors that contribute to the development of a fungal infection include:

• lack of ventilation in the premises;
• stuffy and poorly ventilated rooms;
• sharp jumps in air temperature;
• the presence of condensate in the premises;
• insufficient tightness of food packaging.

Application in industry

Beginning in the 1920s, strains of Aspergillus niger began to be used to make citric acid from sugary substances. During the production of the product in the reactor, the volume of which is 300 cubic meters, 15 tons of aspergillus cell mass is formed. This biomass is then burned.

From the cell wall of fungi, glucose oxidase is extracted, which is used in test strips to determine blood sugar levels. Hydrogen peroxide, being a product of the reaction of D-glucose with glucose oxidase, oxidizes the substance, changing the color.

Aspergillus niger enzymes cellulase, pectinase and hemicellulase are widely used in the production of fruit juices and purees. This increases the efficiency of raw material processing. They are also used in pulp and paper mills and in the manufacture of detergents.

Aspergillus niger is a source of the enzyme glucoamylase, which breaks down starch. It is used in the production of maltose and maltose syrups. Derived from a fungus, xylanase is used by bakers to improve the evenness and porosity of baked goods..

Entry into the human body

The most common way Aspergillus black enters the human body is inhalation of air with spores. Most often, people whose occupation is associated with infection with a fungal infection are:

• with grain processing;
• with baking craft;
• with spinning;
• with cheese making.

Often infection with the fungus Aspergillus niger occurs in the following ways:

• through food;
• through the mucous membrane;
• through microcracks and wounds on the skin.

Long-term treatment with antibiotics and radiation therapy increases the chances of fungus penetration.

Symptoms and testing

Despite being the most common pathogen of its kind, Aspergillus niger also infects many organs.

After a while, a person develops coughing with off-white sputum. Sometimes there are blood clots in it. Also, the patient has signs of intoxication of the body: lethargy, fatigue, decreased performance, weight loss. Ineffective treatment leads to the appearance of pulmonary mycosis. This condition is accompanied by a severe wet cough, fever, chest pain and shortness of breath. Sputum examination revealed Aspergillus spores.

When Aspergillus niger VKPM F1331 gets into the eyeballs, symptoms of blepharitis, conjunctivitis and dacryocystitis are observed. Ineffective therapy causes partial or complete loss of vision.

If infection of the skin of the hands and nails occurs, symptoms such as peeling, itching, unpleasant odor, infiltration are observed. With inactivity, the color of the nail gradually changes from yellow-brown to greenish-brown. In addition, the nail plate thickens and its structure becomes porous.
Diagnosis of the disease includes instrumental (CT, X-ray) and laboratory methods (sputum, urine, serological tests). Once the diagnosis is confirmed, treatment should be started immediately.

How to remove Aspergillus niger

To get rid of the fungus, it is necessary to approach its treatment in a complex manner. Often a specialist prescribes a number of medicines:

• Mycotic drugs against aspergillosis niger - Amphotericin B, Voriconazole, Flucytosine and Itraconazole. The funds are issued in different forms(inhalation, orally or intravenously).
• Topical medicines - antifungal ointments and antiseptics. Mainly used for cutaneous aspergillosis.

In advanced form, pulmonary aspergillosis is fatal in 50% of cases.

Room processing

As a rule, black mold is typical for old damp and corner apartments in multi-storey buildings. Therefore, the inspection of such premises plays an important role in the prevention of the disease.

The fungus Aspergillus niger lives behind wallpaper, in ventilation and at tile joints. To avoid contracting aspergillosis, follow these rules:

• Conduct a general cleaning of the bathroom with antibacterial agents at least once every 3 months.
• Do not allow dampness in the basement, as well as deposits of rotting vegetables.
• Do not install wooden shelves and ceilings in damp houses.
• If black mold appears on the wall, you need to think about its integrity and insulation.

However, this is not the only fungus that a person encounters every day. How to identify and not get infected with it, read in our separate material.

Aspergillosis is a fungal disease caused by fungi of the genus Aspergillus that affects humans and manifests itself in the appearance of primary foci in the lung tissue, a variety of clinical lesions that, in case of severe immunodeficiency, can lead to death.

Mushrooms of the genus Aspergillus are widely distributed in nature and are found in soil, hay, grain, dust of various premises, especially after processing animal skins and hair. An important epidemiological point is their frequent sowing in dust particles of medical institutions, which determines the possibility of nosocomial fungal infections.

Causes of Aspergillosis

The causative agent is mold fungi of the genus Aspergillus, the most common representative of which is Aspergillus fumigatus (80% of all cases of aspergillosis), less often Aspergillus vlavus, Aspergillus niger and others. Mushrooms of the genus Aspergillus (or Aspergillus spp.) belong to mold fungi, are heat-resistant, a favorable condition for existence is high humidity. Fungi of the genus Aspergillus are often found in residential areas, often found on the surface of unsuitable food products. The pathogenic properties of aspergillus are determined by the ability to secrete allergens, which is manifested by severe allergic reactions, lung damage, an example of which can be bronchopulmonary aspergillosis. Also, some of the representatives of fungi can secrete endotoxin that can cause intoxication. Aspergillus are resistant to desiccation, can be stored in dust particles for a long time. Detrimental to fungi are solutions of formalin and carbolic acid.

The mechanism of infection is aerogenic, and the main route is air-dust: with dust particles, fungi of this genus enter the respiratory tract. There are occupational risk groups for aspergillosis infection: agricultural workers; employees of weaving mills and spinning enterprises, as well as immunocompromised patients of medical hospitals who are at risk of nosocomial infection.

An additional mechanism of infection is endogenous infection with aspergillus in case fungi of this genus are already present on the mucous membranes. The main factor contributing to the endogenous spread of the infection is immunodeficiency, in which in 25% of cases mycoses of various etiologies develop, but the main share of which (up to 75%) is aspergillosis.

A person with aspergillosis is not contagious to others, such cases have not been described.

The susceptibility of the population is universal, however, people with weakened immunity become ill during chronic diseases, oncological processes, after transplantation of organs and tissues, with HIV infection and others. Seasonality in aspergillosis was not noted.

Immunity after an infection is unstable, repeated diseases occur in the group of immunodeficient patients.

The pathogenic effect of Aspergillus spp. per person

The entrance gate of infection in the vast majority of cases is the mucous membrane of the upper respiratory tract. At first, aspergillus are located superficially, then they deepen, causing ulceration of the mucous membrane.

Aspergillosis, site of injury

1) Even healthy person when inhaling a large concentration of aspergillus spores, pneumonia can develop - interstitial pneumonia. Distinctive feature interstitial pneumonia in aspergillosis is the formation of specific granulomas, consisting of giant epithelial cells (the so-called epithelioid cell granulomas). Aspergillus granulomas (aspergilloma) are spherical in shape and are centrally located foci of purulent inflammation, in which fungal hyphae are located, and giant cells along the periphery. Aspergilloma localization sites are the upper parts of the lungs, which is confirmed on the x-ray. Fungi are found in the affected bronchial mucosa, in lung cavities, bronchiectasis foci and cysts; in this form, fungi do not penetrate into the lung tissue (non-invasive aspergillosis).

2) In parallel with the defeat respiratory system with aspergillosis, there is a decrease in the immunological reactivity of the body (immunodeficiency). Cases of complications of concomitant diseases of internal organs, mucous membranes and skin are described. An example is lung abscesses, chronic bronchitis, bronchiectasis, lung cancer, tuberculosis, against which a pulmonary form of aspergillosis arose, which, of course, caused a complication of the main process. Recent decades show the incidence of aspergillosis in immunocompromised individuals (HIV-infected, cancer patients receiving immunosuppressive therapy, organ recipients).

3) One of the possible lesions in aspergillosis is damage to internal organs and systems (invasive aspergillosis), which occurs in the overwhelming majority of cases against the background of a significant decrease in immunity. Up to 90% of patients with this lesion have two of the possible three features:
the number of granulocytes in the blood is less than 500 cells in 1 µl;
therapy with high doses of glucocorticosteroids;
cytostatic therapy.
In invasive aspergillosis, aspergilloma can form in internal organs. The drift of fungi occurs hematogenously (with blood flow). First, the lungs are affected, followed by the pleura, lymph nodes and other internal organs. Feature - the possibility of the formation of abscesses at the site of granulomas in most cases. The nature of the process resembles septic, in which mortality is quite high (up to 50%).

4) Allergic restructuring of the body - fungal antigens are powerful allergens that can cause allergic reactions with a primary lesion of the bronchopulmonary tree.

Symptoms of aspergillosis

Aspergillosis is classified as invasive (more often the sites of pathogen penetration are affected - the sinuses, skin, lower respiratory tract), saprophytic (otomycosis, pulmonary aspergilloma) and allergic (bronchopulmonary allergic aspergillosis, aspergillus sinusitis).

Clinically, the following forms of the disease are distinguished:
1) bronchopulmonary form;
2) septic form;
3) eye shape;
4) skin form;
5) defeat of ENT organs;
6) damage to bones;
7) other more rare forms of aspergillosis (damage to the mucous membranes of the oral cavity, reproductive system, and others).

Bronchopulmonary form- the most common form of aspergillosis, characterized by symptoms of tracheitis, bronchitis or tracheobronchitis. Patients complain of weakness, the appearance of a cough with gray sputum, possibly with streaks of blood, with small lumps (clusters of fungi). The course of the disease is chronic. Without specific treatment, the disease begins to progress - the lungs are affected with the onset of pneumonia. Pneumonia develops either acutely or complicates the course of a chronic process. In its acute occurrence, the patient's temperature rises to 38-39 ° C, fever of the wrong type (maximum in the morning or afternoon, and not in the evening, as usual). The patient is shivering, worried about a pronounced cough with viscous sputum of a mucopurulent nature or with blood, shortness of breath, chest pain when coughing and breathing, weight loss, lack of appetite, increasing weakness, profuse sweating. On examination, moist small bubbling rales, pleural friction noise, shortening of percussion sound are heard.

Aspergillosis, bronchopulmonary form

Sputum microscopy reveals greenish-grayish lumps containing accumulations of aspergillus mycelium. In the peripheral blood, pronounced leukocytosis (up to 20 * 109 / l and above), an increase in ESR, an increase in eosinophils. Radiologically - inflammatory infiltrates of round or oval shapes with an infiltrative shaft along the periphery, with a tendency to disintegrate.

In the chronic course of aspergillosis, violent symptoms do not occur, the fungal process more often overlaps with an existing lesion (bronchiectasis, abscess, etc.). Patients often complain about the smell of mold from the mouth, a change in the nature of sputum with greenish lumps. Only radiologically, the appearance of spherical shading in the existing cavities with the presence of an air gas layer with the walls of the cavity is noted - the so-called "crescent halo".

Pulmonary aspergillosis, crescent halo

The prognosis of recovery in bronchopulmonary form depends on the severity of the course of the process and the state of immunity and ranges from 25 to 40%.

Septic form of aspergillosis occurs with a sharp suppression of immunity (for example, the stage of AIDS with HIV infection). The process proceeds according to the type of fungal sepsis. Along with the primary lesion of the lungs, the involvement of the internal organs and systems of the patient's body in the process is progressively increasing, the spread of the fungal infection occurs hematogenously. According to the frequency of damage, this digestive system- gastritis, gastroenteritis, enterocolitis, in which patients complain of an unpleasant smell of mold from the mouth, nausea, vomiting, stool disorders with the release of loose stools with foam containing mycelium of the fungus. Often there are lesions of the skin, organs of vision (specific uveitis), brain (aspergilloma in the brain). If aspergillosis develops in an HIV-infected person, then the disease is accompanied by other opportunistic infections (candidiasis, cryptosporidiosis, pneumocystis pneumonia, Kaposi's sarcoma, herpes infection). The prognosis for the disease is often unfavorable.

Aspergillosis ENT organs proceeds with the development of external and middle otitis media, damage to the paranasal sinuses - sinusitis, larynx. When the eyes are affected, specific uveitis, keratitis, and less often endophthalmitis are formed. Other forms of the disease are extremely rare. Aspergillosis of the skeletal system is manifested by the occurrence of septic arthritis, osteomyelitis.

Features of the course of aspergillosis in HIV-infected patients.

Aspergillosis is the most common form of fungal infections in this group of patients. All patients are in the last stage of HIV infection - the stage of AIDS. Aspergillus sepsis develops rapidly, with a severe course and prognosis. The CD4 count usually does not exceed 50/µl. X-ray revealed bilateral focal shading of a spherical shape. Along with the lungs, the organs of hearing (otomycosis) are affected, visual impairment with the development of keratitis, uveitis, endophthalmitis, and the cardiovascular system can often be affected (fungal damage to the valvular apparatus of the heart, endocarditis, myocarditis).

Complications of aspergillosis occur in the absence of specific treatment and against the background of immunodeficiency and represent the occurrence of extensive abscesses, chronic obstructive pulmonary disease, pulmonary fibrosis, damage to internal organs.
The prognosis of the disease in immunodeficiencies is unfavorable.

Diagnosis of aspergillosis

The preliminary diagnosis is clinical and epidemiological. The appearance of certain symptoms of the disease in combination with data on the presence of a specific profession, the presence of a concomitant disease and immunosuppressive therapy, as well as severe immunodeficiency, incline the doctor in favor of possible aspergillosis.

The final diagnosis requires laboratory confirmation of the disease.
1) Mycological examination of the material (sputum, bronchial material - swabs, biopsies of the affected organs, scrapings of the mucous membranes, smears-imprints). From the blood, the isolation of fungi is rare, so a diagnostic blood test is of no value.
2) Serological examination of blood to detect antibodies to aspergillus (ELISA, RSK), an increase in the concentration of IgE.
3) Paraclinical studies: complete blood count: leukocytosis, eosinophilia, increased ESR.
4) Instrumental studies: X-ray examination, CT scan of the lungs (detection of spherical or oval-shaped unilateral or symmetrical volumetric infiltrates, detection of spherical infiltrates in previously existing cavities with crescent-shaped enlightenment along the periphery).
5) Special studies: bronchoscopy, bronchial washings, bronchoalveolar lavage or transthoracic aspiration biopsy, followed by examination of samples in order to identify pathomorphological changes: histologically, foci of necrosis, hemorrhagic infarcts, vascular lesions of an invasive nature, detection of aspergillus hyphae are detected.

Aspergillosis, fungus growth in material

Differential diagnosis is carried out with lung lesions of another fungal etiology (candidiasis, histopalismosis), pulmonary tuberculosis, lung cancer, lung abscess and others.

Aspergillosis treatment

Organizational and regime measures include hospitalization according to indications (severe forms of the disease, invasive aspergillosis), bed rest for the entire febrile period, and a complete diet.

Therapeutic measures include surgical methods and conservative therapy.

1) Conservative drug therapy is a difficult task and is represented by the appointment of antimycotic drugs: itraconazole 400 mg / day orally in long courses, amphotericin B 1-1.5 g / kg / day intravenously with severe immunodeficiencies, voriconazole 4-6 mg / kg 2 r / day intravenously, pospaconazole 200 mg 3 r / day orally, caspofungin 70 mg-50 mg intravenously. Against the background of treatment, titers of antibodies to aspergillus tend to increase, followed by a gradual decrease. The therapy is supplemented with general strengthening drugs, vitamin therapy. All drugs have contraindications and are prescribed exclusively by a doctor and under his control.

2) Surgical methods: lobectomy with removal of the affected areas of the lung.
Often, such methods are effective and are confirmed by the absence of recurrence of the disease. When the process spreads, conservative therapy is connected.

The effectiveness of treatment is higher when using the possibility of reducing the dosages of concomitant glucocorticosteroid and immunosuppressive therapy.

Prevention of aspergillosis

1) Timely and early diagnosis of the disease, timely start of specific treatment.
2) Carrying out medical examinations in occupational risk groups (agricultural workers, employees of weaving mills and spinning enterprises).
3) Alertness in terms of possible aspergillosis in a group of people suffering from immunodeficiencies while receiving immunosuppressive therapy, severe infections (HIV and others). Positive serological tests for antibodies to aspergillus require a thorough examination of the patient for the disease.

Infectious disease specialist Bykova N.I.