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Polybrominated diphenyl ethers in thirteen shark species from offshore and coastal waters of Korea
2015
Lee, Hyun Kyung | Kim, Sang-jo | Jeong, Yunsun | Lee, Sunggyu | Jeong, Woochang | Lee, Won-Chan | Choy, Eun-Jung | Kang, Chang-Keun | Moon, Hyo-Bang
Limited reports are available on polybrominated diphenyl ethers (PBDEs) in sharks. In this study, PBDEs were measured in dorsal muscles (n=105) from 13 shark species collected from offshore and coastal waters of Korea. The PBDE concentrations varied greatly not only among species but also within species of sharks. The major PBDE congeners detected in our samples were BDEs 47, 28, 99, 153, 100, and 154. Concentrations of PBDEs in sharks in this study were lower than those reported for previous studies. The high PBDE concentrations were found for aggressive shark species. Inter-species differences in the concentrations and accumulation profiles of PBDEs are explained by differences in feeding habits and sampling locations. Several contributing factors such as growth velocity, trophic level, and local contamination may affect the bioaccumulation of PBDEs in sharks. The present study provides baselines for the occurrence and accumulation status of PBDEs in various shark species.
Mostrar más [+] Menos [-]Identification and determination of optimum growth condition with respect to selected environmental parameters for open sea cultivation of Gracillaria edulis in Andaman water
2022
Panja, Atanu | Peter, Malarvizhi J | Nayagi, N. | Maruthupandi, N. | Ganesan, M. | Haldar, Soumya
Gracilaria edulis is one of India's most widely cultivated seaweeds. Pilot scale cultivation of Gracilaria edulis was initiated at Andaman, India for the first time. In the present study attempt has been made to identify how different water quality parameters influence the growth. Total 11 physicochemical parameters and 9 microbiological parameters, as well as chlorophyll and zooplankton, phytoplankton parameters were studied for two different seasons to evaluate which parameters influence seaweed growth. Six (nitrate, nitrite, ammonia, silicate, chlorophyll, photosynthetic active radiation) have a positive impact on seaweed growth, while some of the bacterial species showed negative impact. Lowess 3D curve fit model showed pH range from 7.59 to 7.82, N/P ratio of 2.046, rainfall 23.85–24 mm, and Photosynthetic active radiation of 376.6 W/m² are optimum for Gracillaria growth. This model can be applied to future mass culture.
Mostrar más [+] Menos [-]HSP70 as a Biomarker: an Excellent Tool in Environmental Contamination Analysis—a Review
2018
Moreira-de-Sousa, Cristina | de Souza, Raphael Bastão | Fontanetti, Carmem Silvia
HSP70 are the most studied proteins and among all HSPs are highlighted due to their high sensitivity and abundance, as well as being ubiquitously expressed and associated with all subcellular compartments. For this reason, this work specifically approaches HSP70, since its multiple responsibilities actively participate in the homeostasis of all living organisms and its rapid response to any agent stressor is efficient in assessing environmental pollution/contamination processes. HSP70, heat shock proteins thus classified according to their molecular weight of 70 kDa, are proteins that have maintained their structures conserved from the most primitive to the most complex organisms. They belong to the chaperone family, which comprises proteins with different structures that share a common function. In general, they participate in the process of correct folding of proteins; however, it has been described that they also participate in numerous complex processes of metabolism; its synthesis can usually be increased or decreased under stressful conditions. The classical activation of this protein is due to the increase in environmental temperature, but several factors can trigger the gene expression process of this protein, not only as the increase or decrease of heat or cold, but also the exposure to substances of a chemical nature, physical or biological (metals, metabolism inhibitors, chemotherapeutic agents, inflammatory and infectious processes, processes leading to cell death, the cycle of cell division itself and growth factors, cellular mechanisms considered normal). Given the broad repercussion of these proteins in metabolic processes and in organism physiology, numerous studies have evaluated the HSP70 production under adverse conditions, highlighting their connection to pollution and environmental contamination. Hence, this work aimed to literature review the vast array of HSP70 metabolic functions and its possible applications as biomarkers in the evaluation of contaminated environments by compiling the different physiological responses observed in various animal groups exposed to different conditions.
Mostrar más [+] Menos [-]High-Cell-Density Cultivation and Algicidal Activity Assays of a Novel Algicidal Bacterium to Control Algal Bloom Caused by Water Eutrophication
2014
Liao, Chunli | Liu, Xiaobo
To biocontrol algal bloom, a novel algicidal bacterium, Enterobacter sp. NP23, was isolated. This strain has an effective algicidal activity against Chlorella vulgari, Microcystis aeruginosa, Scenedesmus, and Chlorella pyrenoidosa. Meanwhile, the growth factors were assayed to obtain a high cell density of strain NP23. As a result, three growth factors (i.e., KNO₃0.6 %, MnSO₄·H₂O 0.001 %, and K₂HPO₄0.3 %) were determined as the critical roles in enhancing the cell density of 10¹³ CFU/mL. Moreover, algicidal activity assays revealed that strain NP23 exhibited high algicidal activities against M. aeruginosa and Scenedesmus. These results indicate that this wild-type strain would provide a new member for biocontrolling microalgal and cyanobacterial populations in eco-technology.
Mostrar más [+] Menos [-]Platelet-rich plasma as a potential therapeutic approach against lead nitrate- and/or gamma radiation-induced hepatotoxicity
2018
Because of the potential regenerative and cytoprotective effects of its content of numerous bioactive growth factors and cytokines, platelet-rich plasma (PRP) became an attractive biomaterial for therapeutic purposes. Therefore, the current study was designed to investigate the potential therapeutic effect of PRP against lead nitrate- and/or γ-radiation-induced hepatotoxicity. To do so, hepatotoxicity was induced in rats by intraperitoneal administration of lead nitrate (7.5 mg/kg) thrice weekly for two consecutive weeks and/or a whole-body γ-irradiation at a single dose of 6 Gy. Activated PRP (0.5 ml/kg) was injected subcutaneously 24 h after the last dose of lead nitrate and/or γ-irradiation and continued twice weekly for three successive weeks. Lead nitrate intoxication and/or γ-irradiation resulted in a significant elevation of serum alanine transaminase and aspartate transaminase activities accompanied with a significant decrease in serum levels of total protein and albumin. Further, a significant increase in malondialdehyde level and nitric oxide content accompanied with a significant decrease in the reduced glutathione content and the enzyme activities of glutathione-S-transferase, superoxide dismutase, and catalase were observed. Additionally, hepatic extracellular signal-regulated kinase (ERK) and Akt signaling pathways were stimulated. PRP treatment notably ameliorated the induced cell injury, reduced the intracellular oxidative and interestingly increased the upregulation of phosphorylated ERK1/2 and Akt. Moreover, PRP treatment relieved lead nitrate and/or γ-radiation-induced hepatic histological damages. In conclusion, this study sheds the light on a probable therapeutic role of PRP against lead nitrate- and/or γ-radiation-induced hepatotoxicity which might attribute to its ability to activate ERK and Akt signaling pathways.
Mostrar más [+] Menos [-]The impact of hydro-biofuel-wind energy consumption on environmental cost of doing business in a panel of BRICS countries: evidence from three-stage least squares estimator
2018
Zaman, Khalid
The renewable energy sources are considered the vital factor to promote global green business. The environmental cost of doing business is the pre-requisite to analyze sustainable policies that facilitate the eco-minded entrepreneurs to produce healthier goods. This study examines the impact of renewable energy sources (i.e., hydro energy, biofuel energy, and wind energy) on the environmental cost of doing business in a panel of BRICS (Brazil, Russian Federation, India, China, and South Africa) countries, for the period of 1995–2015. The study employed principal component analysis to construct an “integrated environmental index” by using three alternative and plausible factors including carbon dioxide emissions, fossil fuel energy consumption, and chemicals used in the manufacturing process. The environmental index is used as an interactive term with the three cost of doing business indicators including business disclosure index, the cost of business start-up procedures, and logistics performance index to form environmental cost of doing business (ECDB) indicators. The results of three-stage least squares (3SLS) estimator show that foreign direct investment (FDI) inflows supported the green business while trade openness deteriorates the environment, which partially validates the “pollution haven hypotheses (PHH)” in a panel of countries. There is no evidence for environmental Kuznets curve (EKC) hypothesis; however, there is a monotonic decreasing relationship between per capita income and ECDB indicators. The hydro energy supports the sustainable business environment, while biofuel consumption deteriorates the environmental impact on the cost of business start-up procedures. Finally, wind energy subsequently affected the ECDB indicators in a panel of BRICS countries. The overall results conclude that growth factors and energy sources both have a considerable impact on the cost of doing business; therefore, there is a momentous need to formulate sustainable policy vista to magnetize green business across countries.
Mostrar más [+] Menos [-]Effects of growth conditions on the production of neurotoxin 2,4-diaminobutyric acid (DAB) in Microcystis aeruginosa and its universal presence in diverse cyanobacteria isolated from freshwater in China
2015
Fan, Hua | Qiu, Jiangbing | Fan, Lin | Li, Aifeng
Neurotoxins β-N-methylamino-L-alanine (BMAA) and its isomer 2,4-diaminobutyric acid (DAB) have been reported previously in diverse strains of cyanobacteria. In this study, BMAA and DAB were analyzed for two strains of Microcystis aeruginosa incubated with four different levels of phosphate, nitrate, illumination, and temperature, respectively, in order to explore the effects of growth factors on toxin-producing ability of cyanobacteria. Both toxins were also screened in 17 cyanobacterial strains cultured with BG-11 medium and conventional illumination and temperature conditions, and in three field phytoplankton samples collected from different lakes in China. All samples were analyzed using a liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) system coupled with a hydrophilic interaction liquid chromatography (HILIC) column. Results showed that no BMAA was detected in any of the cyanobacterial strains grown under our laboratory culture conditions, or in any of the field samples. Production of DAB in M. aeruginosa was significantly enhanced by extreme concentrations of nutrient and physical factors. Various concentrations of DAB were also present in most cultured samples (13 of 17) of cyanobacteria and were not species specific. This is the first time to report the production of DAB in M. aeruginosa cultured under alterative conditions in laboratory. Occurrence of DAB in most of the strains examined here means that consideration should be given to the presence of this compound in freshwater environment in China.
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