Brilliant Green Phenol Red Lactose Sucrose (BPLS) Agar, also known as Brilliant Green Agar (BGA), is a highly selective solid culture medium formulated for the isolation and differentiation of Salmonella species from food, environmental, feed, and selected clinical samples.

Brilliant green dye provides strong selectivity by inhibiting most Gram-positive organisms and many Gram-negative bacteria. The medium is commonly used after enrichment in less inhibitory broths such as selenite or tetrathionate broth to improve the recovery of stressed or low-count Salmonella.

Peptones and yeast extract supply essential nutrients, lactose and sucrose serve as fermentable carbohydrates, phenol red acts as a pH indicator, and sodium chloride maintains osmotic balance. Non-fermenting Salmonella typically produce pink to red colonies, whereas lactose and/or sucrose fermenters produce yellow to yellow-green colonies due to acid production.

Brilliant green suppresses competing flora while allowing growth of many Salmonella species. Lactose and sucrose fermentation produces acid, which changes the phenol red indicator colour. Non-fermenting organisms such as Salmonella form pink to red colonies. Lactose and/or sucrose fermenters produce yellow to yellow-green colonies due to acid production.

Presumptive Salmonella isolates must be confirmed by appropriate biochemical and, where required, serological testing.