Isolation of bioemulsifier-producing spore-forming microorgamisms from petroleum contamined sites.

COSTAS, LUCIANA; PERA, LICIA MARÍA; RODRIGUEZ, EMILIO; BAIGORI, MARIO DOMINGO

Rosario. Santa Fe, Argentina.

Congreso; SAIB 42 th Annual Meeting.; 2006

SAIB

Isolation of bioemulsifier-pruducing spore-forming microorganisms from petroleum contaminated sites Costas L, Pera LM, Rodriguez E and Baigorí MD PROIMI-CONICET Av. Belgrano y Pje. Caseros, 4000 Tucumán. Tel: 03814344888, e-mail: baigori@proimi.org.ar Introduction: Bioemulsifiers play an important physiological role in hydrocarbon degrading organisms. Their biodegradability is one of the most important assets because it prevents toxicity problems and accumulation in natural ecosystems. Their potential industrial applications include enhanced oil recovery, crude oil drilling, food processing, and cosmetic formulations. The aim of this work was to isolate bioemulsifier-pruducing spore-forming microorganisms from petroleum contaminated sites. Methods: Nutrient broth agar (NBA), NB, SPI medium containing different sugars (sucrose, starch, glucose and glycerol) and NB containing kerosene were used for isolation, selection and partial characterization assays. Emulsion forming and stabilizing capacity were evaluated using kerosene as immiscible liquid. Results and conclusions: Hydrocarbon contaminated soil samples from NW Argentina had an average of 2x108CFU (g of soil)-1. Three emulsifier producer strains were selected. The emulsifier capacity was located mainly in the supernatant. Interesting, two of them (BS18 and BS38) also have this activity associated with the cell. No effect was observed with either the addition of protease or the addition of sugar to the culture medium. Except for glycerol that it has a positive response. Promising emulsifiers activities were also very stable This work was supported by grants PIP 6062 and PIP 6203