Isolation and characterization of a Rhodococcus strain with phenol degrading ability and its potential use for tannery effluent biotreatment

C.E.PAISIO; TALANO MA; GONZALEZ PS; BUSTO VD; RODRIGUEZ- TALOU J; AGOSTINI E

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2012 vol. 19 p. 3430 - 3439

0944-1344

INTRODUCTION: Wastewater derived from leather production may contain phenols, which are highly toxic, and their degradation could be possible through bioremediation technologies. MATERIALS, METHODS AND RESULTS:In the present work, microbial degradation of phenol was studied using a tolerant bacterial strain, named CS1, isolated from tannery sediments. This strain was able to survive in the presence of phenol at concentrations of up to 1,000 mg/L. On the basis of morphological and biochemical properties, 16S rRNA gene sequencing, and phylogenetic analysis, the isolated strain was identified as Rhodococcus sp. Phenol removal was evaluated at a lab-scale in Erlenmeyer flasks and at a bioreactor scale in a stirred tank reactor. Rhodococcus sp. CS1 was able to completely remove phenol in a range of 200 to 1,000 mg/L in mineral medium at 30 ± 2 °C and pH 7 as optimal conditions. In the stirred tank bioreactor, we studied the effect of some parameters, such as agitation (200-600 rpm) and aeration (1-3 vvm), on growth and phenol removal efficiency. Faster phenol biodegradation was obtained in the bioreactor than in Erlenmeyer flasks, and maximum phenol removal was achieved at 400 rpm and 1 vvm in only 12 h. Furthermore, Rhodococcus sp. CS1 strain was able to grow and completely degrade phenols from tannery effluents after 9 h of incubation. CONCLUSION: Based on these results, Rhodococcus sp. CS1 could be an appropriate microorganism for bioremediation of tannery effluents or other phenol-containing wastewaters