MacConkey Agar W/ 0.15% Bile Salts, CV and NaCl Plate is supplied by Micromaster. It is available in the form of a red with purplish tinge coloured medium with a pH in the range of 6.9 to 7.3. The size of each plate is around 90mm and contains around 25ml media. It is advisable to store these plates between 15-25C for maximum efficiency.

Quantity provided: 10 plates/pack

MacConkey agar is a slightly selective and differential plating media mainly used for the detection and isolation of gram-negative organisms from clinical, dairy, food, water, pharmaceutical and industrial sources. It is also recommended for the selection and recovery of the Enterobacteriaceae and related enteric gram-negative bacilli. USP recommends this medium for use in the performance of Microbial Limit Tests. These agar media are selective since the concentration of bile salts, which inhibit gram-positive microorganisms, is low in comparison with other enteric plating media. The original medium contains protein, bile salts, sodium chloride and two dyes. The selective action of this medium is attributed to crystal violet and bile salts, which are inhibitory to most species of grampositive bacteria. Gram-negative bacteria usually grow well on the medium and are differentiated by their ability to ferment lactose. Lactose-fermenting strains grow as red or pink colonies and may be surrounded by a zone of acid precipitated bile. The red colour is due to production of acid from lactose, absorption of neutral red and a subsequent colour change of the dye when the pH of medium falls below 6.8. Lactose non-fermenting strains, such as Shigella and Salmonella are colourless, transparent and typically do not alter appearance of the medium. Peptones are sources of nitrogen and other nutrients. Lactose is a fermentable carbohydrate; bile salts and crystal violet are selective agents that inhibit growth of gram-positive organisms. Neutral red is the pH indicator dye.