[Development and use of a new growth medium for detection and identification of sanitary-indicative microorganisms].

Threat of emergence and spreading of dangerous intestinal infections determines the necessity to control for water quality in its sources in respect of sanitary-indicative microorganisms, thermo-tolerant coliforms and lactose-negative intestinal bacilli testifying fecal pollution. Standard techniques for isolation of enterobacteria are based on use of lactose-containing inhibitory and non-inhibitory growth media such as lactase-peptone and Kessler media. Development of standard, effective, and reliable for use in laboratory conditions accumulation medium for detection of enterobacteria aimed to increase reliability of sanitary-bacteriological monitoring of objects of aquatic environment. Two variants of Eikman medium with an added indicator were designed for differentiation of enterobacteria on the basis of lactose and glucose fermentation with application of a thermo-tolerance test at 44-46 degrees C. Maximal accumulation of coliforms on the developed media in static cultivation conditions and at sensitivity on the level of individual cells was observed after 16 +/- 2 hours, whereas in control inhibitory media--after 22 +/- 2 hours. Studies on sterilization of the developed media in disposable packages byy-irradiation were conducted to elucidate the possibility of their use in field conditions performing analysis in flasks for preservation of high growth properties. In order to reduce time for analysis on confirmation of detection of thermotolerant coliforms, addition of tryptophan in composition of the media was provided, which allows to perform an indole test and definitively confirm the detection of Escherichia coli. Pilot industrial samples of designed media were successively passed the approbation.