Brillant Green Penol Red Lactose Agar - BPL Agar

Specifications

Ingredients Gms/Ltr :
Lactose 15.00
Agar 13.00
Peptone 7.00
Sodium chloride 5.00
Phenol red 0.04
Brilliant green 0.005
* Dehydrated powder, hygroscopic in nature, store in a dry place, in tightly-sealed containers below 25°C
and protect from direct Sunlight.

Instructions for Use :
Dissolve 40.00gms in 1000 ml distilled water. Gently heat to boiling with gentle swirling and dissolve the
medium completely. Sterilize by autoclaving at 15 psi (121°C) for 10 minutes. Cool to 45 - 50°C and pour
into sterile Petri plates.
Appearance: Red - brown colour, clear gel
pH at 25°C: 6.5 ± 0.2

Principle
BPL AGAR (BRILLIANT GREEN PHENOL RED LACTOSE AGAR) is used for isolation and
identification of Salmonellae except Salmonella typhi in faeces, urine and milk and foodstuffs by
separating lactose and sucrose negative bacteria. The Peptone provides the essential nutrient nitrogen for
growth of microorganisms. Brilliant green in the medium inhibits accompanying microorganisms.
Medium contains Lactose, whose degradation to acid is indicated by the pH indicator Phenol red, which
changes its colour to yellow. The indicator exhibits a deep red colour in the alkaline range. Agar is a
solidifying agent. Sodium chloride maintains the osmotic balance of the medium. The growth of the
accompanying Gram-positive microbial flora, Salmonella typhi and Shigella is largely inhibited by brilliant
green. ADAM (1966) recommended that 0.2 % sodium deoxychlolate should be added to the culture
medium to inhibit the swarming of Proteus colonies.