THE PROPERTIES OF SURFACTANTS SYNTHESIZED BY <i>Acinetobacter calcoaceticus</i> ІMV В-7241 ON REFINED AND SUNFLOWER OIL WASTE
The aim of the work was to compare the antimicrobial and anti-adhesive activity (including the abi lity to destroy biofilms), as well as the effect on oil degradation of the surfactants synthesized by the culture of Acinetobacter calcoaceticus IMV B-7241 on refined and sunflower waste. The microbial surfactants were extracted from supernatant of cultural liquid by mixture of chloroform and methanol (2:1). The number of attached cells and the degree of biofilm destruction were analyzed spectrophotometrically. Antimicrobial properties of the surfactants were determined by index of the minimal inhibiting concentration. The concentration of oil in water was analyzed by the gravimetric method after extraction with hexane. It was shown that microbial surfactants synthesized in medium with 2% of both refined and fried oil were characterized by high antimicrobial (MIC with respect to bacterial test cultures 0.8-29 μg/ml, Candida albicans D-6 26 - 58 μg/ml) and anti-adhesive (decreasing number of bacterial and fungal cells of test cultures attached to abiotic surfaces by 35-70%, destruction of biofilms by an average of 40-44%) activity. Increasing concentration of waste oil in the medium to 4% was accompanied by the formation of surfactants with low antimicrobial activity, in the presence of which the degree of oil destruction in water (3-6 g/l) was 80-88% in 20 days, which is 10-16% higher than when using surfactants synthesized in a medium with 2% oil. Obtained data indicate on the need for studies on the effect of cultivation conditions of producer on the properties of synthesized surfactants for the production of final product with stable predetermined properties, depending on the field of practical application.