HiFast™ Coli-nella Water Testing Kit

Principle

Water is basic requirement which is contaminated with chemical and microbial pollutants. The test for chemical pollutants is instant but microbial contamination takes a period of 24-48 hours for confirmation. The constant urge to search a rapid method for the detection has led to the development of HiFast Rapid Coli- nella Detection Kit. The major microbial water contaminants are coliforms- Escherichia coli, Klebsiella pneumoniae, Salmonella, Citrobacter, Vibrio, and Pseudomonas. So this test was designed for the rapid detection and differentiation of these organisms. Recovery of these pathogens is faster and reliable.

The differential growth medium contains enriched nutritive medium which is a source of nitrogen, vitamins and other growth requirements. Selective compounds present in the medium suppresses the growth of gram positive microorganisms. The chromogenic mix incorporated in the medium is cleaved specifically cleaved by E.coli and hence green colour indicates the presence of E.coli. The detection of H2S production is enhanced by the presence of specific H2S detectors. The medium turns black in case of H2S producers such as Salmonella, Citrobacter etc. The presence of a pH indicator helps in the detection and differentiation of lactose fermenters and lactose non-fermenters. Lactose is the fermentable carbohydrate and phenol red is the pH indicator. Lactose fermenting strains ferments lactose and produces acid thereby reducing the pH of the medium which is detected by the pH indicator dye thereby imparting yellow colour to the medium. Lactose non-fermenters do not utilise lactose and hence the colour of the medium remains pink. Pseudomonas enrichment medium is a selective medium which eliminates the accompanying flora and imparts greenish pigment to the broth in presence of Pseudomonas. The tubes are incubated further for upto 24 hours before reporting the results as negative.