DOI: 10.21276/sajp

Pages: 320-329

Bio-surfactants are a class of surface-active molecules derived from microorganisms (yeast, fungi, bacteria). This diverse group of surface active molecules possesses both hydrophilic and hydrophobic moieties in their structure which allows their partitioningin the liquid/liquid, gas/liquid or solid/liquid interfacesresulting into lower interfacial tension. This facilitates their emulsification, foaming, solubilization, detergent and dispersing functioning. These nontoxic, biodegradable and eco-friendlybio-molecules are competent to replace their chemically synthesized counterparts and divulge themselves as a green alternative to be applied in the application field of food, cosmetic, pharmaceutical, petrochemical, bioremediation and others. The chemical composition of bio-surfactants depends on the substrate and the microorganism present. They are also divided into two large sections based on their molecular weight namely low molecular weight and high molecular weight bio-surfactants. The high molecular weight bio-surfactants are also known as bio-emulsifiers. Apart from their well acknowledged surface properties, they are also widely active against a large number of microorganism and functioning as antimicrobials.Glycolipids are most studied low molecular weight biosurfactants, composed of different carbohydrates linked with fatty acids. They are able to form pores and destabilize biological membrane thus functioning as antibacterial, antifungal and hemolytic agents.