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The new modification of potentiometric pH and Eh measuring was developed. The essence of the method is to measure pH and Eh in compact hermetic redox cell. This modification provides reliable and fast pH and Eh measuring with minimum expense of culture liquid (1 cm3 for each measuring). The application of the developed modification in microbiology was shown on the example of bacterial culture Kocuria carniphila isolated from Negev desert soil (Israel). Dynamics of the Eh changing in the growing culture allows establishing the influence of the carbon and energy sources concentration on the microbial growth, the rate of oxygen consumption and character of microbial interaction with toxic compounds. Copiotriphic conditions (800 mg/l C) were shown to be optimal for K. carniphila. It was shown that K. carniphila was resistant to 200 ppm of Cu2+, nevertheless it did not extract Cu2+ out of liquid medium.

An effective express method of determining organic compound concentration in biological systems (soil water extracts, culture liquid etc.) is developed. The method is based on the permanganate redox titration of carbon-containing sample in an acidic medium (pH ≈ 0) at temperature of 100°C. On the example of basic microbial metabolism of monosaccharides, alcohols, organic acids, the suitability of the method for quantitative determination of total organic carbons is shown. The method measures the rate of glucose consumption by Escherichia coli 926 (ATCC 8789) in M9 medium. We created the average calibration curve for determining carbon concentration in multi-component biological samples. The permanganate method provides high accuracy results which are comparable with the widely used phenol-sulfuric acid method. The sensitivity of the method to carbon concentration is 25 mg/l.

The method of sterile anaerobic centrifugation was developed. The essence of the method is centrifuging the suspensions of bacteria or insoluble metal compounds in sealed flasks immersed in a water layer. Dipping flasks in water prevents destruction of the flasks under the centrifugal force. The method provides the possibility to centrifuge in anaerobic (inert gas) atmosphere. Thus, the method allows obtaining biomass of both aerobic and anaerobic microorganisms in a sterile conditions and preparing sterile insoluble metal compounds.