Microbial biosurfactants production
Biosurfactants are microbial metabolites that are arousing great interest due to their versatility and mainly for possible applications in various industrial sectors such as agriculture, pharmaceuticals, cosmetics, food industries, oil recovery and environmental remediation. Biosurfactants are amphipathic compounds, containing a hydrophilic and a hydrophobic moiety, which are classified into low (glycolipid and lipopeptide) or high molecular weight (polymeric complex) compounds. Features such as increased solubility of hydrophilic molecules that reduce surface and interfacial tensions at the oil /water interface of different mixtures allow these biomolecules to play a key role in emulsification, foaming, detergency and dispersion, which are desirable qualities in different industries.
In recent years, there has been an increase in demand for biological compounds such as biosurfactants, which are produced by many microorganisms, as they exert biodegradability, low toxicity, are stable under extreme temperature, salinity and pH conditions. Biosurfactants have wide application compared to chemical surfactants and are economically viable. Biosurfactants are synthesized by a variety of microorganisms, bacteria, yeast and some filamentous fungi, with different molecular structures and surface activity. However, most surfactants are still derived from petroleum, but rapid advances in biotechnology and increasing consumer concern about the use of environmentally friendly products have increased the possibility of using biological surfactants.
Several studies have been performed on biosurfactant production using various microorganisms, such as Bacillus subtilis, Bacillus licheniformis, Pseudomonas aeruginosa, Pseudomonas f1uorescens, Serratia marcescens, Aspergillus ustus, Cladosporium resine. In addition, Candida bombicola and Candida lipolytica yeasts have often been reported in the literature as biosurfactant producers, as well as Yarrowia lipolytica, Saccharomyces cerevisiae and Kluyveromyces lactis, which are recognized as safe according to their “generally recognized as safe” (GRAS) status. That is, they do not offer risks of toxicity or pathogenicity, which allows their use in the food and pharmaceutical industries.
The production of biosurfactants is of considerable importance for the implementation of sustainable industrial processes, such as the use of renewable resources and green products. Due to their diversity, biosurfactants are considered strong candidates for environmental cleaning of pollutants with broad potential for bioremediation actions.
In view of the useful properties of biosurfactants, many aspects such as suitability of more profitable production techniques, identification of new applications, production from microorganisms considered safe, toxicity determination against different living organisms, and confirmation of their biodegradation deserve research aiming to obtain a versatile and ecologically correct molecule for different applications. The work developed in this line of research aims to obtain biosurfactant using low cost substrates, such as kitchen waste oil, from the yeast of genus Wickerhamomyces spp. for application against Aedes aegypiti larvae, phytopathogenic fungi and pathogenic bacteria.
Angélica Cristina de Souza
Disney Ribeiro Dias
Juliete Gomes de Lara de Souza Fernandes
Natalia de Andrade Teixeira
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