BACTERIA OF NOCАRDIA GENUS AS OBJECT OF BIOTECHNOLOGY

Abstract

The literature and own experimental data, concerning biotechnological potential of bacteria of Nocаrdia genus are given. The use of these microorganisms as destructors of aliphatic (octane, pentadecanol, eicosane, octacosane, hexatriacontane, pristane), aromatic (phenol, octylbenzene, phenanthrene, anthracene), nitroaromatic (4-nitrophenol), heterocyclic (pyridine, ?-picoline) hydrocarbons is described. The prospects of use of Nocаrdia in processes of substances bio-transformation (production of daidzein, ibuprofen, nicotinic acid) and synthesis of some valuable metabolites, in particular antimicrobial and cytotoxic substances (ayamycin, transvalencin А, nocathiacin, brasilibactin A, nocaracins etc.) as well as substances with surface-active and emulsifying properties are discussed. The own experimental data concerning optimization of cultivation conditions and intensification of surfactant synthesis on glycerol (byproduct of biodiesel production) by oil oxidizing bacteria strain Nocardia vaccinii K-8, that was isolated from oil polluted samples of soil are presented. The ability of strain K-8 to assimilate some aromatic compounds (phenol, benzene, toluene, naphthalene, hexachlorbenzene, sulfanilic acid and N-phenylanthranilic acid, 0.3–0.5%) was determined. It was shown that the highest oil destruction degree (94–98%) in polluted water (2.6 g/L) was achieved in the case of treatment with suspension of N. vaccinii K-8 cells (9.8 x 107 CFU/mL) after 30 days, while surfactant preparation of post fermentative cultural liquid (100–300 mL/kg) was more effective for remediation (destruction of 74–83% of oil) of oil polluted soil (20 g/kg). It was determined that surfactants (0.085–0.85 mg/mL) and other exocellular metabolites of strain К-8 possess antimicrobial activity against some phytopathogen bacteria of Pseudomonas and Xanthomonas strains. In this connection the quantity of living cells decreased by 80–100% after the treatment with the investigated preparations.

Keywords

• bacteria of Nocаrdia genus
• destruction of oil pollution
• biotransformation
• antibiotics
• surfactants