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

PAISIO C; TALANO MA; GONZALEZ PS; BUSTO VD; RODRÍGUEZ TALOU J; AGOSTINI E

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2012

0944-1344

Introduction Wastewater derived from leather production may contain phenols, which are highly toxic, and t heir 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 strai n, 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 w as identified as Rhodococcus sp. Phenol removal was evaluated a t a lab-scale i n Erlenmeyer flasks and a t 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 m g/ 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 only12h.Furthermore, Rhodococcus sp. C S1 s t rain was able to grow and completely degrade phenols from tannery effluent s after 9 h of incubation. Conclusion Based on these results, Rhodo coccus sp. CS1 could be an appropriate microorganism for bioremediation of tannery effluents or other phenol-containing wastewaters.