UTILIZATION OF SOME PHENOLIC-COMPOUNDS BY AZOTOBACTER-CHROOCOCCUM ANDTHEIR EFFECT ON GROWTH AND NITROGENASE ACTIVITY

Azotobacter chroococcum was isolated from straw-amended soil and found to utilize 4-hydroxybenzoic acid, resorcinol, pyrocatechol and vanill ic acid as sole carbon source. Growth and nitrogenase activity of A. c hroococcum were supported by 8, 6 and 4 mmol/L of 4-hydroxybenzoic aci d, resorcinol and pyrocatechol, respectively, The generation time of 1 .71 h in 4-hydroxybenzoic acid did not significantly differ from the g eneration time of 1.64 h, observed when grown in mannitol. 4-Hydroxybe nzoic acid was utilized rapidly However, the decomposition of other te sted phenolic compounds set in only slowly. It was concluded that this isolate has good potential to utilize some phenolic compounds release d during biodegradation of plant wastes.