No abstract

The objective of the present study was to analyze different sources of carbon (diesel oil, soybean oil and frying oil) to optimize the production of bioemulsifier by a yeast isolated from soil contaminated with diesel oil. A total of 45 autochthonous yeast were isolated from soil contaminated with diesel oil. Cell growth was achieved in soybean oil and frying oil at 30°C and agitation of 200 rpm. Growth in diesel oil was significantly lower, with a mean of 2.99 g/L. Detection of bioemulsifiers was performed with the emulsification index (E24), the drop-collapse test, the flowability of oil and measurement of surface tension. The mean emulsification indices obtained were between 29.27 % and 43 %, with greater production in the cultivation with diesel oil. This study showed that a stronger emulsifying activity is achieved with yeast growing in a medium with diesel oil, and thus that carbon source should be used for bioemulsifier production.