M-HD ENDO BROTH

Description

The coliform group consists of several genera of bacteria belonging to the family Enterobacteriaceae. Estimation or enumeration of these bacteria in water can be done by employing the membrane filter procedure. As related to the membrane filter technique, the coliform group is defined as those facultative anaerobic, gram-negative, non-spore forming rod shaped bacteria that develop red colonies with a metallic sheen at 35?C within 24 hours on an Endo- type medium containing lactose. M-HD Endo Broth is formulated as per Hajna and Damon and is used for the estimation of coliforms in water samples by membrane filtration technique. Sterile cotton absorbent pads are saturated with around 2 ml of M-HD Endo Broth. Membrane filter through which the test water sample has been passed is aseptically placed on these saturated absorbent cotton pads containing the medium. Following an incubation at 35-37?C for 18-24 hours, lactose fermenting coliforms produce pink to rose red colonies with similar colouration to the medium. Non-lactose fermenting coliforms form colourless to faint colonies against the pink background.