A strain to be selected for fermentation process should satisfy the following criteria- it should be able to produce the desired product and produce the product at large scale, it should be a well-known organism, it should be able to grow faster, it should be safe to handle, it should grow in minimal to moderate growth media, it should have optimum growth temperature considerably above 400c, reduces the cooling costs and will be beneficial for isolation procedures at large scale fermentation processes, it should be genetically stable and simple to understand, it should be easier to manipulate it at genetic level, product recovery should be easy from the culture. Either pure cultures can be isolated from their natural habitats or can be acquired by order from culture collection centres.