Avaliação da produção de biossurfactante a partir de diferentes fontes de carbono por Candida guilliermondii.

Abstract

Biosurfactants are surfactants produced by microorganisms and they have been widely studied nowadays due to their biodegradability, low toxicity, and ecological acceptability and stability. They are able to lower the surface and interfacial tension between different phases, and form stable emulsions. The objective of this work was to evaluate the growth of Candida guilliermondii yeast from different carbon sources for the production of biosurfactant. The biosurfactant production was carried out by a submerged fermentation process in a rotatory shaker (30 °C, 200 rpm, 96h), using a mineral medium plus the selected carbon source, such as cane molasses, cashew apple juice and pineapple juice. For the determination of the presence of biosurfactants, emulsification index tests were performed. The obtained results showed that the studied yeasts showed good growth using all of the tested substrates. Acording to the results, the best carbon source to improve the growth was the cashew apple juice because it has the nexts growth parameters: μx= 0,178 h-1, Tg= 3,89 h, Px= 0,126 g.L-1.g-1 and Yx/s= 0,528. But, the best source to improve the emulsification index was the pineapple juice that was 74,02% to motor oil and 67,54% to soybean oil. The obtained emulsification indexes verified the presence of tensoactive substances, showing that the studied and developed bioprocess complies with what was proposed.