Bioremediation of polycyclic aromatic hydrocarbon (PAH) compounds: (acenaphthene and fluorene) in water using indigenous bacterial species isolated from the Diep and Plankenburg rivers, Western Cape, South Africa

Abstract This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25 °C, 30 °C, 35 °C, 37 °C, 38 °C, 40 °C and 45 °C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37 °C, 37 °C, 30 °C and 35 °C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems.

Synthesis, reactions and anticancer activity of some new heterobicylic nitrogen systems bearing acenaphtho [1,2-e] [1,2,4] triazine moiety, part I

Some new heterobicylic nitrogen systems, e.g. acetonitrile derivatives bearing acenaphtho [1,2-e] [1,2,4] triazine moiety have been synthesized and reacted with hydrazine hydrate, acetohydrazide, acids, alkalis, thiosemicarbazide and carbon disulphide. Structural assignment of the synthesized products 2-19 were confirmed by elemental analyses and spectral data [[1]H-NMR and [13]C-NMR determinations]. Some selected compounds showed remarkable anticancer activity

Synthesis, reactions and anticancer activity of some new heterobicylic nitrogen systems bearing acenaphtho[l,2-e] [l,2,4] triazine moiety, part II

Some new heterocycles bearing acenaphtho [l,2-e][1,2,4] triazine moiety were synthesized via condensation of N-[acnaphtho[l,2-e][l,2,4]triazin-9-yl] formamide [2] with nitrogen and oxygen reagents. Structural assignment of the synthesized products 2-16 were confirmed by elemental analyses and [1]H-NMR and [13]C-NMR determinations. Screening for some selected compounds showed remarkable anticancer activity

Degradation of acenaphthene by ozone / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the oxidation of acenaphthene (Ace), a polycyclic aromatic hydrocarbon (PAH) with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation.</p><p><b>METHODS</b>Ozone was generated from filtered dry oxygen by an ozone generator and continually bubbled into a reactor containing 1g/L Ace dissolved in an acetonitrile/water solvent mixture (90/10, v/v) at a rate of 0.5 mg/s. HPLC was used to analyze the Ace concentration. Total organic carbon (TOC) was used to measure the amount of water soluble organic compounds. GC-MS was used to identify the ozonized products. Oxygen uptake rate (OUR) of activated sludge was used to characterize the biodegradability of ozonized products.</p><p><b>RESULTS</b>During the ozonation process, Ace was degraded, new organic compounds were produced and these intermediate products were difficult mineralize by ozone, with increasing TOC of soluble organics. The ozonized products were degraded by activated sludge more easily than Ace.</p><p><b>CONCLUSION</b>Ozonation decomposes the Ace and improves its biodegradability. The ozonation combined with biological treatment is probably an efficient and economical way to mineralize acenaphthene in wastewater.</p>