Designing of Culture Media for Increased Recovery of Total Heterotrophs From Water Samples.

ABSTRACT

Bacteriological examination of water is one of the most important areas of investigation because upto 80% of all sickness and diseases in the world are water related. Heterotrophic bacteria are the least studied indicator for water quality determination. The present investigation encompasses two different approaches to estimate water quality.e.g a) to modify the conventional culture media for maximal recovery of heterotrophs and b) to assess the load of the total aerobic heterotrophs as an indicator from drinking and surface water. Six samples from different sources were examined with nine different media such as NA, MNA, PCA, PCA-6, SDA-8, R2A, SE, SOE, and SSE for comparative evaluation. Among them,SE,SOE and SSE are newly formulated media using soil extract, soybean extract and the combination of both of them respectively.SDA-8 was found to be superior in most cases in relation to its comparative efficiency.SSE medium was also found to be superior in case of two samples. The range of heterotrophic bacterial count on different media varied from 3.0 x104 cfu/100ml to 8.6x 105 cfu/100ml and 9.5x106 cfu/100ml to 7.5x107 cfu/100ml in case of drinking water and surface water respectively.