[Destruction of oil in the presence of Cu2+ and surfactants of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Ac-5017 and Nocardia vaccinii IMV B-7405].

The effect of copper cations (0.01-1.0 mM) and surface-active agents (surfactants) of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Alc-5017 and Nocardia vaccinii IMV B-7405 in the form of culture liquid on the destruction of oil in water (3.0-6.0 g/L) and soil (20 g/kg), including in the presence of Cd2+ and Pb2+ (0.01-0.5 mM), was investigated. It was shown that the degree of oil degradation in water and soil after 20 days in the presence of low concentrations of Cu2+ (0.01-0.05 mM) and culture liquid of strains IMV B-7241, IMV Ac-5017, and IMV B-7405 was 15 - 25% higher than without copper cations. The activating effect of Cu2+ on the decomposition of complex oil and Cd2+ and Pb2+ pollution was established: after treatment with surfactant of A. calcoacelicus IMV B-7241 and R. erythropolis IMV Ac-5017 destruction of oil in water and soil was 85-95%, and after removal of the copper cations decreased to 45-70%. Intensification of oil destruction in the presence of copper cations may be due to their stimulating effect on the activity of alkane hydroxylases as in surfactant-producing strains, and natural (autochthonous) oxidizing microbiota.

[Synthesis of surfactants by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 on industrial waste].

The synthesis of surfactants by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 on industrial waste (food and oil-processing industry, production of biodiesel) was investigated. The possibility of replacing the expensive substrates (n-hexadecane and ethanol) by industrial waste (oil and fat industry, fried sunflower oil, glycerol, liquid paraffin) for the surfactant biosynthesis was established. The conditional concentration of surfactants was maximal on oil containing substrates and exceeded those on n-hexadecane and ethanol 2-3 times. The highest rates of surfactants synthesis were observed on fried sunflower oil with the use of inoculum grown on carbohydrate substrates (glucose, molasses). It was established that the addition of glucose (0.1%) was accompanied by 2-4-fold intensification of surfactants synthesis by R. erythropolis IMV Ac-5017 and N. vaccinii IMV B-7405 on fried sunflower oil (2%).

[Effect of Cu2+ on synthesis of biosurfactants of Acinetobacter calcoaceticus IMV B-7241 and Rhodococcus erythropolis IMV Ac-5017].

Synthesis of biosurfactants (surface-active substances, SAS) was investigated under the conditions of growth of Rhodococcus erythropolis IMV Ac-5017 and Acinetobacter calcoaceticus IMV B-7241 on hydrophobic (n-hexadecane, liquid paraffins, sunflower oil) and hydrophilic (ethanol) substrates depending on concentration (0.01-0.5 mM) and time of copper cations introduction in the medium. It is established that Cu2+ addition in the exponential phase of growth of the strains IMV B-7241 and IMV Ac-5017 on all studied substrates was accompanied by the increase of conventional concentration of SAS by 25-140% as compared with the indices in the medium without copper cations. Maximum synthesis intensification of SAS of A. calcoaceticus IMV B-7241 and R. erythropolis IMV Ac-5017 was observed in the case of Cu2+ introduction in the medium with hydrocarbons. The increase of SAS synthesis in the presence of copper cations is determined by their activating effect on activity of alkane hydroxylase of the both strains, as well as 4-nitroso-N,N-dimethylaniline-dependent alcohol dehydrogenase and enzymes of biosynthesis of surface active glyco-(phosphoenolpyruvate-synthetase) and aminolipids (NADP(+)-dependent glutamate dehydrogenase) in A. calcoaceticus IMV B-7241.

[Effect of surface-active substances of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Ac-5017, and Nocardia vaccinii K-8 on phytopathogenic bacteria].

The effect of surface-active substances (SAS's) of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Ac-5017, and Nocardia vaccinii K-8 on phytopathogenic bacteria has been studied. It was shown that the survival of cells (10(5)-10(7) in a milliliter) of the Pseudomonas and Xanthomonas phytopathogenic bacteria was found to be 0-33% after treatment with SAS preparations of the IMV Ac-5017 and IMV B-7241 strains for 2 h (0.15-0.4 mg/mL). In the presence of N. vaccinii K-8 SAS preparations (0.085-0.85 mg/mL), the number of cells of the majority of the studied phytopathogenic bacteria decreased by 95-100%. These data show prospects for using microbial SAS's for the construction of ecologically friendly drugs for regulating the number of phytopathogenic bacteria.

[Effect of biosurfactants Acinetobacter calcoaceticus K-4 and Rhodococcus erythropolis EK-1 on some microorganisms].

It has been established that the preparations of biosurfactants Rhodococcus erythropolis EK-1 (0.61 -2.1 mg/ml) and Acinetobacter calcoaceticus K-4 (0.15 - 0.22 mg/ml) in a form of supernatants of the cultural liquid show antimicrobial effect in respect of a number of microorganisms (Bacillus subtilis BT-2, Escherichia coli IEM-1, Candida tropicalis BT-5, Candida albicans D6, Candida utilis BVC-65, Saccharomyces cerevisiae OB-3). No inhibiting effect of biosurfactant preparations of R. erythropolis EK-1 on the cells of S. cerevisiae OB-3 and E. coli IEM-I and antifungal effect of the both studied surfactants on Aspergillus niger P-3 and Fusarium culmorum T-7 were revealed. The survival of microbe cells depend on biosurfactants concentration in the preparations, on exposure time as well as on physiological state of test-cultures. It has been established that the surfactant preparations of A. calcoaceticus K-4 had a higher effect on the spores of B. subtilis BT-2, than on vegetative cells, thus decreasing the spore culture survival by 75% in 2 h of exposure.