Aerobic Degradation of Di- and Trichlorobenzenes by Two Bacteria isolated from Polluted Tropical Soils.

Two polychlorinated biphenyl (PCBs)-degrading bacteria were isolated by traditional enrichment technique from electrical transformer fluid (Askarel)-contaminated soils in Lagos, Nigeria. They were classified and identified as Enterobacter sp. SA-2 and Pseudomonas sp. SA-6 on the basis of 16S rRNA gene analysis, in addition to standard cultural and biochemical techniques. The strains were able to grow extensively on dichloro- and trichlorobenzenes. Although they failed to grow on tetrachlorobenzenes, monochloro- and dichlorobenzoic acids, they were able to utilize all monochlorobiphenyls, and some dichlorobiphenyls as sole sources of carbon and energy. The effect of incubation with axenic cultures on the degradation of 0.9 mM 1,4-dichlorobenzene, 0.44 mM 1,2,3- and 0.43 mM 1,3,5-trichlorobenzene in mineral salts medium was studied. Approximately, 80–90% of these xenobiotics were degraded in 200 h, concomitant with cell increase of up to three orders of magnitude, while generation times ranged significantly (P < 0.05) from 17–32 h. Catechol 1,2-dioxygenase and catechol 2,3-dioxygenase activities were detected in crude cell-free extracts of cultures pre-grown with benzoate, with the latter enzyme exhibiting a slightly higher activity (0.15–0.17 lmol min1 mg of protein1) with catechol, suggesting that the meta-cleavage pathway is the most readily available catabolic route in the SA strains. The wider substrate specificity of these tropical isolates may help in assessing natural detoxification processes and in designing bioremediation and bioaugmentation methods

‘Launching’ a new nation: The unfolding brand of South Sudan

In June 2011 South Sudan joined the United Nations as a new state, marking the final stage of years of struggle for independence. Its secession is witness to the potential of regions with no historic claims of statehood to achieve independence. This unique situation gives researchers the opportunity to explore how the brand of a nation comes into existence. This article traces how the brand of a new nation has unfolded in the case of South Sudan and analyzes how that brand was written into existence by international news media. This exploratory case study approach is based on inductive content analysis research processes founded on grounded theory. The research brings new insights to research of nation brands in their very early stages