PRODUCTION OF MICROBIAL METABOLITES AND OPTIMIZATION OF KEY FACTORS INVOLVING THEIR HYPERPRODUCTION IN BATCH CULTURE (REVIEW)

*Sikander Ali, Maria Najeeb, Aiman Tahir Laghari, Maryam Salahuddin and Attia Majeed

ABSTRACT

Fermentation is a metabolic process which uses the sugar in the absence of the Oxygen. However, it can be done both aerobically and anerobically. The products obtained from this process include organic acid, alcohol, gases and many others by-products. One such industrially important by-product is metabolite production. Metabolites are small molecular weight compounds (<2,500 amu) produced as an intermediate or end product of a metabolic reaction. Microorganisms during fermentation process produce not only primary metabolites but secondary, tertiary and quaternary metabolites as well. These metabolites are industrially very important, however for industrial applications the wild-type strains of micro-organisms need to be modifying by strain improvement techniques to enhance the productivity of commercially important compounds. This review will focus on the production of primary and secondary metabolites production with emphasis to the use of both liquid and solid state fermentation along with the various approaches for the enhanced production of the metabolites. Factors such as pH, temperature, types of nutrients, carbon and nitrogen sources, growth factors, metabolic regulators, effect of water, presence of other microbes, strain used and other parameters are also discussed in the view of hyper-production and optimization of the metabolites.

Keywords: Primary metabolites, Fermentation, Trophophase, Vitamins, Secondary metabolites.