Isolation and characterization of Rhodococcus sp. NB5 capable of degrading a high concentration of nitrobenzene

Abstract

An efficient nitrobenzene degrading bacterium strain NB5, which was able to utilize nitrobenzene as a sole source of carbon, nitrogen and energy under aerobic condition, was isolated from activated sludge in an oil refinery at Hangzhou, China. Based on phenotypic features, 16S rDNA gene sequencing and G + C content analysis, strain NB5 was identified as Rhodococcus sp. NB5. Nitrobenzene degradation experiments using high performance liquid chromatograph (HPLC) showed that strain NB5 could tolerate a high nitrobenzene concentration and completely degrade nitrobenzene with initial concentration ranging from 100 mg · l(-1) to 1000 mg · l(-1) within 144 h. The optimal degradation and cell growth were observed at 30 °C, pH 7.0. The addition of second nitrogen source (0.1%) such as urea, peptone, yeast extract and beef extract generally enhanced degradation of nitrobenzene. Rhodococcus sp. strain NB5 could be an excellent candidate for biotreatment of industrial wastewater containing high concentration of nitrobenzene.

Localization of Groundwater Contaminant Sources Using Artificially Enhanced Catchment

“…NB and inorganic ions were released to the groundwater simultaneously In groundwater environment of the site, the migration process of NB includes convection, dispersion, adsorption, and biodegradation. NB in wastewater can be degraded, assisted by microorganism [33,34]. NB in groundwater biodegradation in different conditions was well fitted by the Monod equation and the q max values varied from 0.018 to 0.046 h −1 [35].…”

Microbial Community in a Biofilter for Removal of Low Load Nitrobenzene Waste Gas

“…The genus Rhodococcus belonged to the phylum Actinobacteria , which is known to be capable of NB biodegradation [29–31]. According to Fig 3, the RE of NB was 49.5%-60.3% in the bottom layer; thus, it was concluded that the genus Rhodococcus was the major NB-degrading genus.…”

Nitroaromatic compounds – characteristics and methods of biodegradation

“…zidentyfikowane w ostatnich latach mikro organizmy takie jak: Rhodococcus sp. NB5, zdolny do całkowitej degradacji 1000 mg nitrobenzenu w ciągu 144 h [65] oraz Pseudomonas sp. a3, którego immobilizowane komórki są w stanie degradować 300 mg nitrobenzenu w czasie 10 godzin w obecności dodatkowych związków aromatycznych w postaci aniliny i fenolu [114].…”