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排序方式: 共有282条查询结果,搜索用时 15 毫秒
1.
This study investigated mercury contamination levels in eight commercially valuable crustacean species caught off the Central Adriatic and Tyrrhenian coasts of Italy. Total mercury levels were measured by Thermal Decomposition-Amalgamation-Atomic Absorption Spectrophotometry. Results showed a high variability among species with values ranging from 0.070 to 1.24 (mg kg?1 wet weight). The lowest mercury levels were detected in caramote prawn (Penaeus kerathurus), warty crab (Eriphia verrucosa) and European spider crab (Maja squinado), decapods living in shallow waters. Levels exceeding the limits established by the European Commission were found in species living in close contact with bottom sediments: deepwater rose shrimp (Parapenaeus longirostris), blue and red shrimp (Aristeus antennatus) and Norway lobster (Nephrops norvegicus). For shrimps, the inter-individual variability observed was mostly related to the body size, indicating the accumulation of mercury with age. An estimation of the human intake of mercury associated to the consumption of the crustaceans sampled and its comparison with the Tolerable Weekly Intake are provided.  相似文献   
2.
Abstract

Autism Spectrum Disorders (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are two increasingly prevalent neurodevelopmental disorders. This rise may be associated with a higher dietary intake of n-6 polyunsaturated fatty acids (PUFAs) and lower of n-3 PUFAs. Docosahexaenoic acid (DHA), a key nutritional n-3 PUFA, is crucial for an optimal offspring’s neurodevelopment through the last trimester of pregnancy. Recently, lower DHA levels have been reported in children with ASD and ADHD. The present review summarizes the main research achievements concerning the effect of DHA in children neurodevelopment, in order to elicit its role in the prevention and mitigation of ASD and ADHD. As main finding, a low DHA supply seems to negatively affect childhood neurodevelopment in specific conditions and increase the risk and the severity of ASD or ADHD. Higher DHA status at birth was associated with better childhood neurodevelopmental, but controversial results found in prenatal supplementation raised the hypothesis that the benefits of DHA may be influenced by other factors as socio-economic background and life-style. In conclusion, an optimal DHA provision through maternal diet or breastfeed may promote some neuronal protection in specific offspring’s populations, suggesting that DHA may act as a modifiable risk factor for ASD and ADHD.  相似文献   
3.
杨茜  谢晶 《食品与机械》2015,31(2):187-190
海产品极易腐败变质,贮藏温度是影响海产品货架期和品质的一个重要因素。-4~0℃的中间温度带被广泛研究,其具有抑制有害微生物的生长繁殖,减少海产品的组织破坏和外界损伤,延缓脂质氧化和蛋白质分解等优点。文章综述了中间温度带对海产品感官、微生物、物理和化学品质的影响,以期为中间温度带保鲜贮藏海产品的应用提供理论参考。  相似文献   
4.
Increases in international trade and global seafood consumption, along with fluctuations in the supply of different seafood species, have resulted in fraudulent product mislabeling. Grouper species, due to their high demand and varied commercial availability, are common targets for mislabeling by exploiting inefficient inspection practices. Compounding this problem is the fact that there are currently 64 species of fish from eleven different genera allowed to be labeled “grouper” per U.S. Food and Drug Administration guidelines. This wide diversity makes it difficult for regulators to discern legally salable groupers from restricted species. To obviate taxonomic misidentification when relying on external phenotypic characteristics, regulatory agencies are now employing genetic authentication methods which typically offer species-level resolution. However, standard genetic methods such as DNA barcoding require technical expertise and long turnover times, and the required instrumentation is not amenable for on-site analysis of seafood. To obviate some of these limitations, we have developed a handheld genetic sensor that employs a real-time nucleic acid sequence-based amplification assay (RT-NASBA) previously devised in our lab, for the analysis of fish tissue in the field. The base RT-NASBA assay was validated using a lab-based, benchtop RNA purification method as well as non-portable, commercial RT-NASBA analyzer. Described herein, is an uncomplicated method for purifying RNA from fish tissue in the field, which had similar efficiency to the benchtop method demonstrated through direct comparisons. We have also demonstrated that the field sensor is only slightly less sensitive than the benchtop instrument, and could discern 80.3% of groupers (no target sequence available for three species) on the 2014 FDA Seafood List from potential impostors. The complete field assay requires fewer than 80 min for completion and can be performed outside of the lab in its entirety.  相似文献   
5.
Abstract

The inclusion of nanotechnologies in aquaculture and seafood preservation confronts a new edge that deserves attention in the recent trends of global food sector. Nanotechnology, being a novel and innovative approach has paved way to open up new perspective for the analysis of biomolecules, targeted drug delivery, protein or cells, clinical diagnosis, development of non-viral vectors for gene therapy, as transport vehicle for DNA, disease therapeutics etc. The current and potential use of nanotechnology would show the way to progression of smart and high performing fish. The comparative evaluation of extremely sophisticated nanotechnology with conventional process engineering proposes new prospectus in technological developments for superior water and wastewater technology processes. Nanoparticles have comprehensive advantages for management of drugs as liberation of vaccines and therefore hold the assurance for civilized protection of farmed fish against disease-causing pathogens. This review article explores the present concerns of food security, climate change as well as sustainability that are explored by the researchers in the area of nanotechnology, development of marine produce, along with its preservation and aquaculture.  相似文献   
6.
The aim of this study was to estimate the dietary intake of arsenic (As) by children and adults from Jinhu area of China. A duplicate diet approach was used to collect diet samples in November and December 2007. The As content was measured by hydride generation atomic fluorescence spectrometry. The As intakes (median) for different group were: children: 0.6 µg kg?1 bw day?1 or 6.7 µg kg?1 bw week?1; adults: 0.5 µg kg ?1 bw day?1 or 3.8 µg kg ?1 bw week?1, none of which exceeded the provisional tolerable weekly intake (PTWI) of 15 µg kg ?1 bw week?1 for As proposed by the World Health Organization (WHO). The median and maximum of the children group amounted to 44.7% and 125.3% of the PTWI; the values for adults were 25.3% and 118.7%, respectively. There were 3.3% of children whose weekly As intake exceeded the PTWI, and there were 6.7% of adults whose weekly As intake exceeded the PTWI. It is concluded that dietary As intake was safe for most people in Jinhu area, but the high dietary As intake for a minority of people in this area deserves attention.  相似文献   
7.
This study investigated accumulation of Vibrio parahaemolyticus in granulated ark shell clam (Tegillarca granosas) exposed to contaminated water and survival of V. parahaemolyticus in the clams during cold storage and heating processes. Vibrio parahaemolyticus could be accumulated in clams to a level similar to that of contaminated water within 12 h of exposure of clams to contaminated water at temperatures between 9 and 33 °C. Keeping clams stored at 5 and 0 °C for 10 days resulted in 1.98 and 2.32 log MPN g?1 reductions of V. parahaemolyticus, respectively, in the clams. Frozen storage at ?18 °C for 15 days or at ?30 °C for 30 days were capable of reducing V. parahaemolyticus from 4.05 log MPN g?1 to non‐detectable levels (< 3 MPN g?1). A heating process in hot water at 80 °C or higher for 1 min also reduced V. parahaemolyticus in the clams to non‐detectable levels.  相似文献   
8.
BACKGROUND: Sustainable technologies need to be developed to treat saline seafood wastewater (SSW) efficiently. This study focused on the feasibility of a continuously operated microbial fuel cell (MFC) with modified anoxic/oxic (A/O) architecture (A/O–MFC) for power generation and treatment of SSW simultaneously. RESULTS: Hydraulic retention time (HRT) was shown to have an impact on polarization and power output of the A/O–MFC and the maximum power density of 16.2 W m?3 was obtained at a current density of 41.7 A m?3 and HRT of 4.2 h. High salinity together with advective flow mode enabled a low and constant internal resistance of approximately 100 Ω throughout the experiments. Besides, pH of waste stream in both compartments was found always near neutral level. Increasing HRT could improve eliminability of soluble chemical oxygen demand (sCOD) and biological nitrification. CONCLUSIONS: This study provides a proof‐in‐concept demonstration to utilize an MFC for effective and sustainable treatment of SSW along with recovery of electrical energy. Copyright © 2010 Society of Chemical Industry  相似文献   
9.
10.
目的对青岛近海主要海捕水产品开展质量安全与营养评价研究,掌握捕捞水产品的食用安全现状。方法全面分析青岛近海海域主要捕捞水产品中常量元素、微量元素、稀土元素以及石油烃的含量,并进行食用安全评价分析。结果研究表明青岛近海海域水产品中含有丰富的人体必需元素,是补充人体矿物质营养的良好膳食来源。稀土元素总含量为6.08~232μg/kg,且甲壳类高于鱼类。水产品中鱼类的有害微量元素及石油烃含量均符合我国水产品有毒有害物质限量标准,但甲壳类中梭子蟹和虾蛄的镉(Cd)和少数样品中石油烃含量存在超标情况。结论亟需进一步加强水产品中有害元素的形态分析研究,科学开展风险评估。  相似文献   
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