Ways to reduce the labor intensiveness of applying the method of optical estimation of microbial cell concentration in suspension

Abstract

The labor intensity (in hours) of the optical method of microbial cell counting in suspension compared to the method of microbial cell counting using a Goryaev chamber is evaluated. The relevance of assessing the production labor intensity of microbial cell counting methods in suspension is related to the need to use them in many studies. Often the commonly used methods are too labour-intensive, time-consuming, or require expensive equipment. A comparative experiment was carried out with our previously developed “Method for optical estimation of microbial cell concentration in suspension” (Priority certificate No. 2016141859 dated 25.10.2016) and the method of microbial cell counting using a Goryaev chamber. Production labor intensity of the measurements performed was calculated in hours according to the formula: Tp=Tt+Tob, where Tp is production labour input, Tt is technological labour input, Tob is maintenance labour input. Technological labour input of measurements with use of Goryaev’s chamber made up 32,18 ± 0,95, whereas with optical method - 1,03±0,06 (reliability of differences at p<0,01) at amount of measurements n = 100. Labour input of service at optical method 0,24 ± 0,03, at application of method with use of Goryaev chamber 0,15±0,01 hours. Labour input of measurements of concentration of microbial cells in suspension at application of method of measurement with Goryaev chamber remains (p<0,01) higher than at an optical method of estimation, 32,33±0,96 and 1,27±0,05 hours accordingly. When using the optical method of concentration estimation in the suspension it is necessary to carry out not a small amount of necessary mathematical calculations, which in the future, probably, corrected by creating a special program for a personal computer. The labour input of results obtained by measuring by optical evaluation of the concentration of microbial cells in suspension is lower than that obtained by using a measurement method using a Goryaev chamber. Taking into consideration that its implementation does not require purchase of special equipment as in turbidimetry, its cost-effectiveness compared to existing ones is obvious.