PRODUCTION OF AUXIN-LIKE COMPOUNDS AND SIDEROPHORES BY OCHROBACTRUM RHIZOSPHAERAE IMV B-7956 UNDER THE INFLUENCE OF NaCl

Abstract

The ability of Ochrobactrum rhizosphaerae IMV B-7956 bacteria to produce auxin-like compounds and siderophores at various NaCl concentrations was investigated. The bacteria, isolated from filtrates of the Lviv municipal solid waste landfill, were cultured in LB liquid medium containing NaCl concentrations of 0.5, 2.5, 4.5, and 6.5 % for 5 days. On days 3, 4, and 5 biomass accumulation and the content of auxin-like compounds and siderophores in the culture medium were determined. Auxin-like compounds and siderophores were determined using a spectrophotometric method, while biomass was determined by weighing. It was found that the NaCl concentration affected both bacterial growth and the production of the studied metabolites; the highest biomass accumulation was observed at 4.5 % NaCl, whereas the addition of 6.5 % NaCl significantly inhibited culture growth. The highest production of siderophores was recorded at 4.5 % NaCl on days 4 and 5 of cultivation, whereas the highest levels of auxin-like compounds were predominantly observed at lower NaCl concentrations. The results obtained confirm the promise of further study of the biotechnological potential of O. rhizosphaerae IMV B-7956 bacteria.