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Antibiotic resistance of culturable heterotrophic bacteria isolated from shrimp (Penaeus vannamei) aquaculture ponds 全文
2021
Nadella, Ranjit Kumar | Panda, Satyen Kumar | Madhusudana Rao, B. | Pani Prasad, K. | Raman, R.P. | Mothadaka, Mukteswar Prasad
Shrimp aquaculture is one of the fastest growing food-producing avenues, where antibiotics usage has become an issue of great concern due to the development of antimicrobial resistance in bacteria. A total of 2304 bacterial isolates from 192 samples (sediment, water, shrimp, and source water) from Andhra Pradesh, India were screened. Antibiotic resistance of bacterial isolates was highest for oxytetracycline (23.4%) followed by erythromycin (12.7%), co-trimoxazole (10%) ciprofloxacin (9.6%), and chloramphenicol (6%), of which 11.9% isolates were multi-drug resistant. Bacterial isolates from shrimp (26.7%), water (23.9%), and sediment (19.6%) samples exhibited more resistance (p ≤ 0.05) towards oxytetracycline. Higher antibacterial resistance was observed from samples of southern Andhra Pradesh (locations L6 and L7). Gram negative bacteria were more prevalent (64%) and showed significantly (p ≤ 0.01) higher resistance. This study indicated the wider distribution of antibiotic-resistant bacteria in shrimp aquaculture ponds with potential risk to humans and the environment.
显示更多 [+] 显示较少 [-]Integration of multi criteria decision analysis and GIS for evaluating the site suitability for aquaculture in southern coastal region, India 全文
2021
Shunmugapriya, K. | Panneerselvam, Balamurugan | Muniraj, Kirubakaran | Ravichandran, Nagavinothini | Prasath, P. | Thomas, Maciej | Duraisamy, Karunanidhi
Deterioration of water and soil quality, poor infrastructure facilities and improper maintenance are the major factors that govern aquaculture growth and production in major part of India. In the present study aims to identify the suitable land for aquaculture growth and suggest the sustainable practice to improvise the growth of aquaculture in study region. With use of analytical hierarchy process (AHP) the various significant parameters such as geology, pH, salinity, soil media, slope, geomorphology, land use land cover, distance to water, settlement and road networks were analyzed and based on these characteristics, thematic maps were prepared. The results are revealed that, that 882.13 km² area was most suitable, 1264.88 km² area was suitable and 14.00 km² area was unsuitable for aquaculture in the study region. The study results will helpful to decision makers and to make a design plan for aquaculture growth in the study region.
显示更多 [+] 显示较少 [-]A proteomic analysis of skeletal tissue anomaly in the brain coral Platygyra carnosa 全文
2021
Wong, Yue-Him | Zhang, Yu | Lun, Janice C.Y. | Qiu, Jian-Wen
Coral skeletal growth anomaly (GA) is a common coral disease. It has been considered as a pathological condition comparable to abnormal tissue growth in mammals, but little is known about the molecular changes underlying coral GA. To investigate the molecular pathology of GA, we compared the proteome between normal and GA-affected tissues of the brain coral Platygyra carnosa using iTRAQ-labeling and LC-MS/MS, which quantified 818 proteins and identified 117 differentially expressed proteins (DEPs). GO analyses revealed DEPs that might be related to GA included “translational elongation”, “proteasome core complex”, “amine metabolic processes” and “lysosome”. Several proteins implicated in calcification and fluorescence were differentially expressed at both protein and mRNA level. Protein-protein interaction network suggested possible involvement of TNF receptor signaling in GA. Overall, our results provided novel insights into the molecular pathology of coral GA, which will pave the way for determination of the causative agent(s) of this coral disease.
显示更多 [+] 显示较少 [-]Oxidative stress responses in brackish water flea exposed to microcystin-LR and algal bloom waters from Nakdong River, Republic of Korea 全文
2021
Won, Eun-Ji | Kim, To-gyun | Yoo, Je-Won | In, Soyeon | Shin, Kyung-Hoon | Lee, Young-Mi
Microcystis blooms and the impact of their toxins, particularly microcystin (MC), in coastal ecosystems is an emerging threat, but the species-specific effects of MC and the potential for bioconcentration are not fully understood. We exposed the brackish water flea, Diaphanosoma celebensis, to MC-LR, which showed antioxidant responses measured at the molecular to enzyme levels but no acute toxicity. We extended our experimental investigation to measure the released MC and its uptake by D. celebensis exposed to river water. In a short-term exposure (48 h) experiment, D. celebensis exposed to water from an algal bloom (approximately 2 μg L⁻¹ MC) assimilated more than 50 pg MC per individual. The significant increase of MCs suggests the potential for the species to accumulate MCs. The dose-dependent increase in the antioxidant response observed in the mRNA levels also showed that D. celebensis exposed to diluted algal bloom waters were affected by toxins from cyanobacteria.
显示更多 [+] 显示较少 [-]Potential microplastic release from beached fishing gear in Great Britain's region of highest fishing litter density 全文
2021
Wright, Luka Seamus | Napper, Imogen Ellen | Thompson, Richard C.
While land-based sources of marine plastic pollution have gained widespread attention, marine-based sources are less extensively investigated. Here, we provide the first in-depth description of abandoned, lost or otherwise discarded fishing gear (ALDFG) on northern and southern beaches of the English Southwest Peninsula, Great Britain's region of highest ALDFG density. Three distinct categories were recorded: twisted rope (0.28 ± 0.14 m⁻¹, 17%), braided rope (0.56 ± 0.28 m⁻¹, 33%) and filament (0.84 ± 0.41 m⁻¹, 50%), which likely correspond to fishing rope, net and line. Estimating the disintegration of ALDFG from length and filament number suggests that it has the potential to generate 1277 ± 431 microplastic pieces m⁻¹, with fishing rope (44%) and net (49%) as the largest emitters. Importantly, ALDFG was over five times more abundant on the south coast, which is likely attributable to the three times higher fishing intensity in that area.
显示更多 [+] 显示较少 [-]Climate change alters shellfish reef communities: A temperate mesocosm experiment 全文
2021
Cole, Victoria J. | Parker, Laura M. | Scanes, Elliot | Wright, John | Barnett, Lauren | Ross, Pauline M.
Climate change is expected to cause significant changes to rocky shore diversity. This study used outdoor mesocosms to test the predictions that warming and ocean acidification will alter the responses of native Trichomya hirsuta and introduced Mytilus galloprovincialis mussels, and their associated communities of infauna. Experiments consisted of orthogonal combinations of temperature (ambient 22 °C or elevated 25 °C), pCO₂ (ambient 400 μatm or elevated 1000 μatm), mussel species (T. hirsuta or M. galloprovincialis), and mussel configuration (native, introduced, or both), with n = 3 replicates. Elevated pCO₂ reduced the growth of T. hirsuta but not that of M. galloprovincialis, and warming and pCO₂ influenced the infauna that colonised both species of mussels. There was a reduction in infaunal molluscs and an increase in polychaetes; there was, however, no effect on crustaceans. Results from this study suggest that climate-driven changes from one mussel species to another can significantly influence infaunal communities.
显示更多 [+] 显示较少 [-]Unprecedented Impacts of Aviation Emissions on Global Environmental and Climate Change Scenario 全文
2021
Sher, Farooq | Raore, David | Klemeš, Jiří Jaromír | Rafi-ul-Shan, Piyya Muhammad | Khzouz, Martin | Marintseva, Kristina | Razmkhah, Omid
There has been a continuously growing trend in international commercial air traffic, with the exception of COVID-19 crises; however, after the recovery, the trend is expected to even sharpen. The consequences of released emissions and by-products in the environment range from human health hazards, low air quality and global warming. This study is aimed to investigate the role of aviation emissions in global warming. For this purpose, data on different variables including global air traffic and growth rate, air traffic in different continents, total global CO₂ emissions of different airlines, direct and indirect emissions, air traffic in various UK airports and fuel-efficient aircraft was collected from various sources like EU member states, Statista, Eurostat, IATA, CAA and EUROCONTROL. The results indicated that in 2019, commercial airlines carried over 4.5 × 10⁹ passengers on scheduled flights. However, due to the COVID-19 pandemic in 2020, the global number of passengers was reduced to 1.8 × 10⁹, representing around a 60% reduction in air traffic. Germany was the largest contributor to greenhouse gas (GHG) from the EU, releasing 927 kt of emissions in 3 years. In the UK, Heathrow airport had the highest number of passengers in 2019 with over 80 million, and the study of monthly aircraft movement revealed that Heathrow Airport also had the highest number of EU and International flights, while Edinburgh had the domestic flights in 2018. These research findings could be beneficial for airlines, policymakers and governments targeting the reduction of aircraft emissions.
显示更多 [+] 显示较少 [-]Microplastic's story 全文
2021
Schmid, Chiara | Cozzarini, Luca | Zambello, Elena
The problem of microplastic pollution is now the order of the day in front of everyone's eyes affecting the environment and the health of leaving creature. This work aims to retrace the history of microplastics in a critical way through a substantial bibliographic collection, defining the points still unresolved and those that can be resolved. Presence of marine litter in different environments is reviewed on a global scale, focusing in particular on micro and macro plastics definition, classification and characterization techniques.
显示更多 [+] 显示较少 [-]Dietary intake of trace elements from commercially important fish and shellfish of Thoothukudi along the southeast coast of India and implications for human health risk assessment 全文
2021
Shalini, Rajendran | Jeyasekaran, Geevaretnam | Shakila, Robinson Jeya | Sundhar, Shanmugam | Arisekar, Ulaganathan | Jawahar, Paulraj | Aanand, Samraj | Sivaraman, Balasubramanian | Malini, Asha Hema | Surya, Tamizhselvan
The concentrations of eight trace elements (chromium, cobalt, copper, zinc, arsenic, cadmium, mercury and lead) in14 commercially important fish and shellfish collected from Thoothukudi along the southeast coast of India was investigated using inductively coupled plasma mass spectrometry in order to assess the health risks associated with their consumption. The concentration of trace elements ranged from 0.001 to 39.5 μg/g. The estimated weekly intake of cadmium in seven fish and shellfish (0.0081–0.0996 mg/kg body weight) were above the provisional tolerable weekly intake set by the Joint FAO/WHO Expert Committee on Food Additives. The risk assessment analysis indicated that there was non- carcinogenic risk upon lifetime consumption of rock crab, C. natator (TTHQ >1) and carcinogenic risks upon lifetime consumption of S. jello, P. semisulcatus, P. sanguinolentus C. natator, Uroteuthis duvaceli, Sepia pharaonis and Cistopus indicus due to cadmium exposure indicating a potential health risk to the exposed consumers.
显示更多 [+] 显示较少 [-]Baseline concentrations of pharmaceuticals in Kuwait's coastal marine environment 全文
2021
Gevao, Bondi | Uddin, Saif | duPont, Sam
This study was carried out to provide baseline information on the concentrations of pharmaceuticals in Kuwait's coastal waters. Samples were collected over four sampling campaigns from various outfalls that occasionally discharged water into the marine environment and analyzed for a range of pharmaceuticals including analgesic/anti-inflammatories, antibiotics, anticoagulant, antidiabetic, antihelmintics, antihypertensives, antiplatelet agent, asthma medication, β-blocking agent, calcium channel blocker, diuretic, histamine H1 and H2 receptor antagonist, lipid regulators/cholesterol-lowering, prostatic hyperplasia, psychiatric drug, sedation and muscle relaxant, synthetic glucocorticoid, tranquilizer and x-ray contrast media. The levels varied between the detection limits of the method and a maximum of 28,183 ng/L for analgesics/anti-inflammatories. The highest pharmaceutical concentrations were in samples collected during the September campaign, possibly linked to the increased prescription of these medications to treat infectious diseases and flu prevalent in Kuwait during the winter months. The spatial variation is concentration is evident with KISR site being most polluted as hospital wastewater is discharged at the site. This study provides the first dataset on the concentrations of pharmaceuticals in the seawater in Kuwait and possibly the wider Arabian Gulf. Kuwait's coastal water pharmaceutical concentrations derived from this study exceed those reported from the Spanish coast, the Hong Kong harbour, the Bohai and the Yellow seas. More studies are needed to evaluate the environmental impact that these residues may have on non-target organisms.
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