HiMedia offers a broad range of Medias for Microbial Limit Testing (MLT) methods used in pharmaceutical Industries. The Microbial Limit Test is a primary and simple design to enumerate the number of microorganisms in terms of colony forming units (CFU) in a non-sterile product or raw material. The routine Microbial limit screening test consists of the total aerobic, yeast and mold counts as well as the test for objectionable microorganisms. The usual procedure involves, immersing the solution and then plate aliquots to determine the CFU/gram (or ml) of initial sample. The plating can be either pour plate, spread plate or the filtration of material and then placing the membrane filter on the surface of an agar plate. In case the product cannot be put into solution, then most probable Number Method can be employed where series of dilutions of the sample is carried out in a specified number of tubes containing suitable medium and under specified incubation conditions, will give an estimate of the microbial population of the product using most probable number tables. Another method i.e. Membrane Filtration is generally used when there are few expected colony forming units in the sample to be tested as it is a good method to test a large volume of liquid, but can only count up to approximately 100 CFU/membrane. |