CRITICAL REVIEW OF BIOSURFACTANTS AND THEIR ROLE IN BIOREMEDIATION OF PETROLEUM HYDROCARBON CONTAMINANTS.

Biotechnological advances for the past decades have provided new surfactant production technologies. Surface active substances (biosurfactants) produced by fermentative processes have proven to be a safer and sustainable alternative to many synthetic molecules. Biosurfactants are a promising substitute due to their synthesis potential by a wide variety of microorganisms. They are a highly diverse group of structures, such as glycolipids, lipopeptides, polysaccharide-protein complexes, phospholipids, fatty acids, and neutral lipids. This diversity promotes many advantages compared to synthetic surfactants, thereby making biosurfactants a suitable choice for technological advances associated with sustainable development. Such advantages include fermentative production viability using renewable resources, effectiveness in small concentrations even under extreme conditions, selective and specific potential for several applications, lower toxicity, higher biodegradability, and better stability to physicochemical variations. Despite these benefits enumerated, they are not widely used because of the high production costs. Hence, finding cost-effective substrates is imperative to making biosurfactants an economically competitive product against synthetic surfactants. In this review, inexpensive and renewable substrates that can be used for biosurfactants production are discussed. Also, biosurfactants and their potential use in bioremediation of hydrocarbon contaminants, and effectiveness in bioremediation of hydrocarbon contaminants compared to synthetic surfactants are reviewed. Keywords: Biosurfactants, Hydrocarbon degradation, Bioremediation, Environment.