FIELD: chemistry.
SUBSTANCE: method involves collecting dust samples with a sterile cotton wool wad from 10-20 cm2 of any surface or the sterile cotton wool filter of a vacuum cleaner. The dust samples are put into a sterile physiological solution, followed by extraction for 30-60 minutes at room temperature while stirring. The supernatant liquid is collected and multiple cultures of the obtained extract are prepared from the liquid. The obtained cultures are sown in a semi-liquid thioglycol medium and modified thioglycol medium obtained by adding defibrinated blood to the thioglycol medium in a given amount. Culturing is performed for 10 days at temperature 37°C and daily visual monitoring, followed by determining the number of microbial cells which are calculated from the McCready probability table, which is compiled based on data on growth properties of microorganisms and tinctorial properties of the bacterial community of the dust sample are determined through microscopic examination of smears of the mixed culture mass which is gram-stained.
EFFECT: simultaneous quantitative determination of the total bacteria number and obtaining cultural, morphological, tinctorial and haemolytic characteristics of the bacterial community of dust samples from buildings.
