21 research outputs found
Characterization of the parent and hydroxylated polycyclic aromatic hydrocarbons in the soil of the Fildes Peninsula, Antarctica
Polycyclic aromatic hydrocarbons (PAHs) and hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) were investigated in the soil of the Fildes Peninsula, Antarctica. Various analytes were detected, and the concentration of OH-PAHs was 0.300–1.847 ng·g−1 dry weight, with the dominant components being danthron and 1-hydroxy-phenanthrene. The relationship between soil total organic matter (TOM), OH-PAHs, and the parent PAHs in the soil was studied. No significant correlation was detected between the spatial distribution of OH-PAHs and the occurrence of PAHs, whereas a positive correlation with TOM was found
Distribution of organochlorine pesticides and polychlorinated biphenyls in Ny-Ålesund of the Arctic
Sediment, moss and animal-dropping samples were collected from Ny-Ålesund of the Arctic to investigate the distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the Arctic area. OCPs and PCBs were analyzed using the capillary gas chromatography (GC-ECD). Recoveries of three surrogates were at a range of 69.5~92.2% (mean: 78.8% ) , 75.1~112.1% (98.5%) and 67.7~95.1% (79.5%) , and the relative standard deviations were 6.7% , 8.0% and 11.3% , respectively. The major monomers of OCPs were hexachlorocyclohexanes (HCHs) and DDTs. Their concentrations were at a range of 0.86~4.50 ng/g (mean: 2.24 ng/g) and 0.22~1.09 ng/g (mean: 0.55 ng/g). The concentrations of PCBs were 0.20~3.25 ng/g (mean: 0.84 ng/g) and the major congeners were tetra-, penta-, and hexa-PCBs, which were up to 23.8%、26.7% and 32.3% of total PCB s, respectively. Based on the results of the ratio analysis and the principal component analysis, the atmospheric transport is believed be one of the major input ways of OCPs and PCB s in the Ny-Ålesund of the Arctic
Distribution Patterns and Ecological Risk of Endocrine-Disrupting Chemicals at Qingduizi Bay (China): A Preliminary Survey In a Developing Maricultured Bay
The occurrence and estrogenic activities of seven phenolic endocrine-disrupting chemical (EDC) compounds (nonylphenol (NP), octylphenol (4-OP), 2,4-dichlorophenol (2,4-DCP), 4-tertbutylphenol (4-t-BP), 4-tert-octylphenol (4-t-OP), tetrabromobisphenol A (TBBPA), and bisphenol A (BPA)) in the sediments of Qingduizi Bay (NorthernYellow Sea, China) in superficial sediments were investigated to evaluate their potential ecological impacts on the health of aquaculture organisms. All compounds, except 4-OP and 4-t-BP, were recorded in most sampling sites (1.06–28.07 ng g−1 dw in maricultural ponds (MPs), 1.98–8.22 ng g−1 dw in outer bay (OB)). BPA and 4-t-OP were the predominant EDC compounds in MPs and OB, respectively. Correlation between BPA and 4-t-OP indicated these compounds may share a similar source or pathway. Analyzed estrogenic activity revealed a low risk of total EDCs. The ranking of risk quotient showed 4-t-OP posed a median risk and TBBPA posed a high risk to the aquatic ecosystem
Identification and fermentation optimization of a marine-derived <i>Streptomyces Griseorubens</i> with anti-tumor activity
14-21 The purpose is an attempt to investigate a potential anti-tumor actinomycete WBF9 isolated from Chinese marine sediment. MTT assay was firstly used to evaluate anti-tumor activity and ID50 value was defined as dilution fold of fermentation broth (FB) that caused 50% inhibition of cell growth. The results reveal its strong anti-tumor activity against Hela, KB and SMMC7721 cells with the ID50 values of 750.3, 921.2 and 803.5, respectively. The strain was identified as Streptomyces griseorubens according to the 16S rRNA gene sequence analysis, along with the morphological, physiological and biochemical characteristics. The present study also reveals the strain WBF9 required natural seawater for good growth and production of anti-tumor metabolites. This implies some degree of marine adaptation of the strain. The one-factor-at-a-time method was used to investigate the enhanced anti-tumor activity of nutrients. The concentration of the four nutritional components was optimized by the orthogonal matrix method. The effects of the nutritional components for improving anti-tumor activity were found to be in the order of CaCl2>potato extract>yeast extract>glucose and the optimal concentrations were determined as glucose (1% w/v), potato extract (15% w/v), yeast extract (0.6% w/v) and CaCl2 (0.12% w/v). With the optimized medium, ID50 value of FB reached the maximum level of 1946.8 in 1-l flask after 7d of fermentation, which was 2.1-fold higher than that with the basal medium. It indicated a significant increase of anti-tumor activity of FB. The ethyl acetate extract was preliminarily isolated and the resulting four fractions showed anti-tumor activity. The initial identification data demonstrated that active fractions contained alkaloid, terpene, peptide, and indican. The strain of Streptomyces griseorubens being isolated from the sea was firstly reported here, and its anti-tumor activity was initially investigated in this paper. </smarttagtype
Distribution Characteristics and Source of Dechloranes in Soil and Lichen of the Fildes Peninsula (Antarctica)
Dechloranes (Decs) have been widely found in the environment, even in the Tibetan Plateau and remote polar regions. However, the understanding of their regional distribution characteristics in polar regions is limited. To study the long-range atmospheric transport and fates of these emerging contaminants, Decs were analyzed in soil and lichen from the Fildes Peninsula in Antarctica. The concentrations of five Decs in soil and lichen ranged from 141.46 to 838.47 pg/g dw and 237.04 to 3599.18 pg/g dw, respectively. The mean fractions of anti-Dechlorane Plus (DP) (fanti) values estimated in the current soils (0.37) and lichen (0.24) were lower than those of commercial products (fanti = 0.64–0.80), which confirms that long-range atmospheric transport is a main source of DP, and the DP burdens could be driven by the accumulation of syn-DP. The average ΣDP concentration in soil in the coastal area was higher than that in the inland area and Ardley Island, while in lichen, the average DP concentration at the Ardley Island site was approximately three-fold higher than that in the coastal area and inland areas. This indicates that the distribution of DP was influenced by anthropogenic interference and animal activities in the Fildes Peninsula. The spatial variation of fanti of the three regions was clearer in soil than that in lichen. The fanti values were negatively correlated with DP concentrations in soil, suggesting that DP concentration levels play an important role in determining the isomeric composition of DP in the soil
Photochemical degradation of hydroxy PAHs in ice: Implications for the polar areas
Hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) are derived from hydroxylated PAHs as contaminants of emerging concern. They are ubiquitous in the aqueous and atmospheric environments and may exist in the polar snow and ice, which urges new insights into their environmental transformation, especially in ice. In present study the simulated-solar (λ > 290 nm) photodegradation kinetics, products and pathways of four OH-PAHs (9-Hydroxyfluorene, 2-Hydroxyfluorene, 1-Hydroxypyrene and 9-Hydroxyphenanthrene) in ice were investigated, and the corresponding implications for the polar areas were explored. It was found that the kinetics followed the pseudo-first-order kinetics with the photolysis quantum yields (Φs) ranging from 7.48 × 10−3 (1-Hydroxypyrene) to 4.16 × 10−2 (2-Hydroxyfluorene). These 4 OH-PAHs were proposed to undergo photoinduced hydroxylation, resulting in multiple hydroxylated intermediates, particularly for 9-Hydroxyfluorene. Extrapolation of the lab data to the real environment is expected to provide a reasonable estimate of OH-PAH photolytic half-lives (t1/2,E) in mid-summer of the polar areas. The estimated t1/2,E values ranged from 0.08 h for 1-OHPyr in the Arctic to 54.27 h for 9-OHFl in the Antarctic. In consideration of the lower temperature and less microorganisms in polar areas, the photodegradation can be a key factor in determining the fate of OH-PAHs in sunlit surface snow/ice. To the best of our knowledge, this is the first report on the photodegradation of OH-PAHs in polar areas
Occurrence and gasparticle partitioning of PAHs in the atmosphere from the North Pacific to the Arctic Ocean
Occurrence and gasparticle partitioning of PAHs in the atmosphere from the North Pacific to the Arctic Ocea