Abstract
Biosurfactants are amphipathic molecules with hydrophobic and hydrophilic moieties, which can be obtained by bacteria, yeasts and filamentous fungi. In recent years, the scientific production with a focus on obtaining these bioproducts from industrial waste has increased. This alternative stems from the need to reduce production costs, since biosurfactants are not yet economically competitive against synthetic surfactants, which are petroleum-based, toxic and not biodegradable. Among the properties of biosurfactants we can cite the surface tension reduction, low toxicity, biodegradability, diversity, specificity, dispersing ability, emulsifying, demulsifying, antimicrobial and antioxidant activities. Such properties make biosurfactants attractive for application in several areas. In this sense, the present study evaluated the emulsifying and antioxidant capacity of the biosurfactant produced from low cost substrates by Candida bombicola URM 3718. The emulsifying capacity of the biosurfactant against vegetable oils was compared with guar gum, a vegetable origin emulsifier of common use in the food industry. The total antioxidant capacity (TAC) of the biomolecule was evaluated by the phosphomolybdenum method, seeking the reduction of molybdenum VI in molybdenum V by the antioxidant substance. According to the results, it was possible to verify that the biosurfactant presented excellent emulsification rates when compared to guar gum. The variation of the biosurfactant concentration had little effect on the results. On the other hand, in the results obtained for the antioxidant activity, it was verified that the increase of the concentration of the biosurfactant contributes to the increase of the percentage of TAC. Thus, it can be concluded that the biosurfactant obtained from low-cost substrates has potential for application in food systems, where emulsification and the introduction of antioxidants are extremely important for the useful life of food.
