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Resistance to the existing drugs and increasing numbers of diseases result in identifying new drug candidates with new forms of activity. As marine organisms are well known to provide a wide range of original compounds, Herein, we report the synthesis of new non-natural brominated, iodinated and chlorinated-substituted 1-O-alkylglycerols 5–7, analogs of a prominent 1-O-alkylglycerol (AKG) of the natural shark liver oil (SLO) mixture, namely the AKGs 18:1, n-9. [ABSTRACT FROM AUTHOR]

Halogenated compounds pose long-term potential risks to the well-being of humans due to their recalcitrance and persistent toxicity. The quest for microorganisms capable of degrading such perilous substances merits urgent consideration. In this study, a new dehalogenase-producing bacterium was isolated from a hypersaline environment (TuzGölü Lake, Turkey), and identified as Bacillus megaterium strain CTBmeg1 (Accession number MK128900). Under culture conditions (pH 8.0, NaCl 20%, 30 °C, 200 rpm, 9 days), the B. megaterium strain CTBmeg1 showed an optimum growth on 10 mmol/L of 2,2-dichloropropionic acid with a doubling time of 26.41 h. Furthermore, the presence of a putative halotolerant dehalogenase gene (dehCTBmeg1) of B. megaterium strain CTBmeg1 was detected and amplified via PCR technique. Bio-prospecting for microorganisms in a highly saline environment capable of utilizing halogenated compounds as the sole carbon may prove to be a practical and safer means for bioremediation of contaminated coastal areas, an increasingly common place predicament faced by many nations. [ABSTRACT FROM AUTHOR]

Industries and agriculture activities extensively utilize halogenated compounds. These compounds were found to be toxic and pollute the environment. Thus, many studies have been done on microbial degradation of these chemicals. In this study, an attempt was made to isolate bacterial strains EK1–EK5 from marine sediments collected at Danga Bay and east coast of Singapore island. The 16S rRNA analysis suggested that the isolated bacteria had more than 96% sequence identity to the sequence in the database; therefore, they were designated asBacillussp.,Rhodococcussp.,Lysinibacillussp.,Microbacteriumsp., andAminobactersp. The results of molecular analysis were supported by biochemical and microscopic examinations. Bacterial isolates were able to grow slowly in minimal medium containing only 2,2-dichloropropionate as the sole carbon source. The cellular doubling times were 39.60 ± 0.1, 36.60 ± 0.2, 30.71 ± 0.1, 41.23 ± 0.1, and 36.70 ± 0.3 h for EK1, EK2, EK3, EK4, and EK5, respectively. In the future, it will be important to further investigate the presence of the dehalogenase gene in their genomic DNA for further characterization. [ABSTRACT FROM PUBLISHER]

With increased economic growth in East Asia, regional emissions of many anthropogenic halogenated compounds now constitute a substantial fraction of the global totals. Here, we summarize recently reported findings from measurements of a wide range of chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), and other halogenated compounds at Gosan (Jeju Island, Korea) within the advanced global atmospheric gases experiment (AGAGE). General wind patterns at Gosan bring air masses from the surrounding areas, allowing the monitoring of both clean baseline and polluted air masses. We have analyzed our measurements since November 2007 both with an interspecies correlation method and with an inversion method based on the FLEXPART Lagrangian particle dispersion model to estimate these regional emissions. The results show that emissions of halogenated compounds in East Asia account for over 20% of global emissions, both in terms of ozone depletion potential (ODP) and global warming potential (GWP), and emphasize the importance of atmospheric measurements for quantifying emissions of these compounds in this region. [ABSTRACT FROM AUTHOR]

Solid phase microextraction (SPME) has been optimized and applied to the determination of the volatile halogenated compounds (VHCs) and semi-volatile halogenated compounds (SVHCs). Three types of SPME fiber coated with different stationary phases (PDMS—100 μm, CAR/PDMS—75 μm, PDMS/DVB—65 μm) were used to examine their extraction efficiencies for the compounds tested. Experimental parameters such as the selection of SPME coatings, extraction time, and addition of salts were studied. The carboxen-polydimethylsiloxane (CAR/PDMS) fiber appears to be the most suitable for the determination of VHCs. Analytical parameters such as linearity, limit of detection, and precision were also evaluated. Application of ECD detector for the determination of VHCs and SVHCs allows their determination on the low concentration level, ranging from 0.005 to 0.8 μg/L-1. The HS-SPME-GC/ECD procedure gave good analytical precision expressed as relative standard deviation (RSD) (ranged from 5.08% to 8.07%) for a concentration level of 5 μg/L-1 and good linearity (r2 >0.98) in a wide calibration range. The applied HS-SPME-GC/ECD method was found to be a quick and effective technique for the determination of microtrace amounts of volatile and semi-volatile halogenated compounds in samples containing high amounts of various organic compounds. [ABSTRACT FROM AUTHOR]