Abstract
It is well known that the general creation of biosurfactants is hampered by the lack of economical anduniversal products. Currently, there is only a very limited supply of commercially available biosurfactants,such as surfactin, sophorolipids and rhamnolipids. A variety of new biosurfactants, respectively producingstrains, is a key problem in overcoming economic obstacles to the production of biosurfactants. Therefore,it is necessary to make more efforts to discover new microorganisms producing biosurfactants, applying awide range of different screening methods, which is the subject of this review. Biosurfactants are surfaceactive agents synthesized by various microorganisms. Recently, biosurfactants have aroused great interest,since these substances are not inferior to chemical analogues. They are characterized by environmentalfriendliness, biodegradability and high antimicrobial activity. Biosurfactants are used in many industries(pharmaceutical, cosmetic, food, chemical), in agriculture, as well as in environmental sciences. Biosurfactants are components that effectively reduce the surface tension of the medium, and also have a highemulsifying activity. Microorganisms that habitat in soil contaminated with various substances (oil, coal,etc.) secrete biosurfactants of exotype and endotype nature. The purpose of this study is the selection ofmicroorganisms that synthesize biosurfactants and study their biological properties.Key words: brown coal, biosurfactants, biosolubization, bioconversion, antimicrobial activity, surface-active substances (surfactants), emulsifying activity.