[Biological Properties of Nocardia vaccinii IMV B-7405 Surfactants Synthesized on Byproduct of Biodiesel Production].

Aim: Comparison of antimicrobial and anti-adhesive activity of Nocardia vaccinii ІMV B-7405 surfactants synthesized on purified and technical glycerol (byproduct of biodiesel production).

Methods: Surfactants were extracted from supernatant of cultural liquid by mixture of chloroform and methanol (2:1). Antimicrobial against bacteria and yeast properties of the surfactant was determined by index of the minimum inhibitory concentration (MIC). The number of attached cells was determined spectrophotometrically.

Results: The dependence of surfactant antimicrobial and anti-aghesive activity on the degree of glycerol purification (purified, technical), as well as the duration of N. vaccinii IMV B-7405 cultivation on these substrates was established. MIC against studied test cultures surfactants, synthesized on technical glycerol during 5 days, was 15–121 μg/ml, that lower than MIC of surfactant obtained on purified substrate (22.5−180 μg/ml). Increasing duration of N. vaccinii ІMV B-7405 cultivation accompanied by rise the MIC against some test cultures surfactants synthesized on both technical and purified glycerol. Adhesion of the bacteria Escherichia coli ІEM-1, Bacillus subtilis BT-2 (vegetative cells and spores) and the yeast Candida albicans Д-6 on abiotic surfaces treated with surfactants synthesized on technical glycerol for both 5 and 7 days, was an average of 11−12 % less than after materials treatment with surfactants obtained on the purified substrate.

Conclusions: Increasing activity of NADP+-dependent glutamate dehydrogenase − key enzyme of aminolipids biosynthesis (effective antimicrobial and anti-adhesion agents) in the presence of K+ and Na+ may indicate the possibility of biosynthesis intensification of these components of surfacrants complex under N. vaccinii ІMV B-7405 cultivation on technical glycerol, which is characterized by a high content of sodium and potassium cations. Replacing refined glycerol on byproduct of biodiesel production will not only reduce the cost of N. vaccinii ІMV B-7405 surfactant biosynthesis, but also to obtain the final product with high antiadhesive and antimicrobial activity.