ANTIBIOTIC ASSAY MEDIUM NO.2 (BASE AGAR) (VEG.)

Antibiotic Veg Assay Medium No. 2 is prepared by incorporating vegetable peptones in place of animal peptones, making the medium BSE, TSE risks free. It can be used for the same purpose of Antibiotic Assay Medium No. 2 and is recommended for use as base agar for microbiological agar diffusion assays for wide variety of antibiotics. Agar diffusion assays can be performed by cylinders, punched-hole or paper disc tests. The equivalent animal based medium is identical numerically with the name assigned by Grove and Randall that is equivalent to the Antibiotic Assay Medium No. B of Indian Pharmacopoeia.
This medium is widely used to prepare the base layer in the microbiological assay of antibiotics such as Bacitracin, Cephalexin, Cephalothin, Cephapirin, Cloxacillin, Dicloxacillin, Methicillin, Nafcillin, Oxacillin, Chloramphenicol, Novobiocin and Penicillin. To perform the antibiotic assay the Antibiotic Veg Assay medium No.2 is used as base agar. This medium should be prepared on the same day as the test. For the cylinder method, a base layer of 21 ml is required. Once the base medium has solidified, Antibiotic assay medium No.1 as seed agar, inoculated with the standardized culture can be overlaid. Even distribution of the layer is important.

for microbiological assay of antibiotics