MacCONKEY BROTH PURPLE (IS: 5401-1:2012)

Description

MacConkey Broth Purple is recommended for detection and estimation of coliforms in foodstuff and for presumptive identification of coliforms from a variety of specimens such as water, milk and food. This medium is recommended for use in microbiological examination of foodstuff and for direct inoculation of water samples for coliform counts. This medium is also used for the Examination of Milk and Dairy Products and pharmaceutical preparations. The selective action of this medium is attributed to Sodium taurocholate which are inhibitory to most species of gram-positive bacteria. Gram-negative bacteria usually grow well on the medium and are differentiated by their ability to ferment lactose. Lactose fermenting strains grow as yellow coloured. The yellow colour is due to production of acid from lactose. Lactose non-fermenting strains, such as Shigella and Salmonella are colourless and transparent and typically do not alter appearance of the medium.