咸水鱼类与淡水鱼类营养物质研究

对六种咸水鱼类和五种淡水鱼类的营养物质的含量作了比较研究。认为淡水鱼类与咸水鱼类的氨基酸和营养物质的含量相近似，总体上无显著差异。认为咸水鱼类的营养比淡水鱼类传统观点缺乏科学根据，应加以修正。     

在线固相萃取/高效液相色谱法检测熏烤鱼及熏烤肉制品中的多环芳烃

基于在线净化富集技术,建立了熏烤鱼和熏烤肉制品中15种欧盟优控多环芳烃的在线固相萃取/高效液相色谱-紫外/荧光(Online-SPE/HPLC-UV/FLD)检测方法。对提取溶剂和流动相进行优化,样品采用乙腈-丙酮(6∶4)匀浆处理,超声提取后,在线固相萃取柱Chrom Spher Pi(80 mm×3 mm)净化富集,反相C18PAH专用柱(250 mm×4.6 mm i.d.,5μm)分离,水、乙腈和异丙醇梯度洗脱,紫外和荧光检测器检测。结果表明,15种多环芳烃在相应的浓度范围内线性良好(r20.999);检出限为0.03~8.33μg/kg;熏烤鱼的回收率为67.4%~107.2%,相对标准偏差(RSD)为0.2%~7.7%;熏烤肉的回收率为71.8%~110.5%,RSD为0.8%~8.9%。经FAPAS质控样品验证,所测化合物种类和浓度范围均满足要求。     

Solid Lipid Nanoparticles Administering Antioxidant Grape Seed-Derived Polyphenol Compounds: A Potential Application in Aquaculture

The supply of nutrients, such as antioxidant agents, to fish cells still represents a challenge in aquaculture. In this context, we investigated solid lipid nanoparticles (SLN) composed of a combination of Gelucire^® 50/13 and Precirol^® ATO5 to administer a grape seed extract (GSE) mixture containing several antioxidant compounds. The combination of the two lipids for the SLN formation resulted in colloids exhibiting mean particle sizes in the range 139–283 nm and zeta potential values in the range +25.6–43.4 mV. Raman spectra and X-ray diffraction evidenced structural differences between the free GSE and GSE-loaded SLN, leading to the conclusion that GSE alters the structure of the lipid nanocarriers. From a biological viewpoint, cell lines from gilthead seabream and European sea bass were exposed to different concentrations of GSE-SLN for 24 h. In general, at appropriate concentrations, GSE-SLN increased the viability of the fish cells. Furthermore, regarding the gene expression in those cells, the expression of antioxidant genes was upregulated, whereas the expression of hsp70 and other genes related to the cytoskeleton was downregulated. Hence, an SLN formulation containing Gelucire^® 50/13/Precirol^® ATO5 and GSE may represent a compelling platform for improving the viability and antioxidant properties of fish cells.     

Monitoring Farmed Fish Welfare by Measurement of Cortisol as a Stress Marker in Fish Feces by Liquid Chromatography Coupled with Tandem Mass Spectrometry

The aquaculture industry has become a sustainable source of food for humans. Remaining challenges include disease issues and ethical concerns for the discomfort and stress of farmed fish. There is a need for reliable biomarkers to monitor welfare in fish, and the stress hormone cortisol has been suggested as a good candidate. This study presents a novel method for measurement of cortisol in fish feces based on enzymatic hydrolysis, liquid–liquid extraction, derivatization, and finally instrumental analysis by liquid chromatography coupled with tandem mass spectrometry. Hydrolysis and extraction conditions were optimized. Cortisol appeared to be mostly conjugated to sulfate and less conjugated to glucuronic acid in the studied samples of feces from farmed Atlantic salmon. The method was suitable for quantification of cortisol after enzymatic deconjugation by either combined glucuronidase and sulfatase activity, or by glucuronidase activity alone. The limit of detection was 0.15 ng/g, the limit of quantification was 0.34 ng/g, and the method was linear (R² > 0.997) up to 380 ng/g, for measurement of cortisol in wet feces. Method repeatability and intermediate precision were acceptable, both with a coefficient of variation (CV) of 11%. Stress level was high in fish released into seawater, and significantly reduced after eight days.     

一种基于混合人工鱼群的图像模糊增强算法

模糊隶属度函数的形式直接影响灰度图像增强的质量。为进一步改善图像模糊增强的效果,对目前的模糊隶属度函数进行研究,并提出一种改进的参数化 型模糊隶属度函数用于图像增强。所提算法利用图像对比度的质量评价模型,结合人工鱼群算法和Powell算法搜索 型函数中的未知参数值,进而确定该模糊隶属度函数。通过实验结果表明：该算法能够较好的改善灰度图像质量,并且控制参数可通过优化算法自适应获得,具有较好的通用性,是一种有效的图像模糊增强算法。     

Effects of Green Tea Marinade in the Bioaccessibility of Tonalide and Benzophenone 3 in Cooked European Seabass

Fish consumption is an indicator of human exposure to personal care products (PCP) such as tonalide (AHTN) and benzophenone 3 (BP3). Although most fish consumed is cooked, the impact of cooking procedures on PCP levels is difficult to evaluate. Hence, the aim of this work was to provide thorough information on the stability and bioaccessibility of AHTN and BP3 upon cooking and in vitro digestion. A green tea (Camellia sinensis) marinade, rich in polyphenol, was used as mitigating strategy to reduce these contaminants. Roasting and frying reduced AHTN and BP3 levels in European seabass (Dicentrarchus labrax) spiked samples. Additionally, the green tea marinade promoted a reduction of up to 47% AHTN and 35% BP3. Bioaccessibility of AHTN was higher (up to 45%), and increased with the use of green tea marinades. BP3 showed a bioaccessibility below 19% in all cooked samples. Overall, a decrease in PCP levels was observed after cooking; this decrease was even more pronounced when marination was previously used. However, this decrease is cancelled out by the fact that the bioaccessible fraction of the contaminants increases in an inverse way; therefore, none of these processes can be considered a mitigating alternative.     

Applicability of MALDI‐TOF MS for determination of quinolone residues in fish

MALDI‐TOF MS approach for determination of six quinolones residues in fillets of pangasius (Pangasionodon hypophthalmus) was studied, considering that is a very sensitive analytical technique with simple and high‐throughput operation, contributing to knowledge regarding application of this technique to the determination of small‐molecular‐weight organic compound residues in foods. LIFT‐MS/MS showed to be a successful approach to identify the presence of all quinolone residues in the fish fillet, at their respective MRL level. This study opens an important field of research for the development of simple and high‐throughput bioanalytical screening methods for the determination of veterinary drug residues in foods.     

A sonochemical assisted synthesis of hollow sphere structured tin (IV) oxide on graphene oxide sheets for the low-level detection of environmental pollutant mercury in biological samples and foodstuffs

In modern approaches for nanomaterials synthesis, ultrasonication plays an important role in providing the larger surface area and smaller crystalline size properties that are favorable to electrochemical techniques. Herein, we report the tin (IV) oxide on graphene oxide nanoparticles were synthesized (SnO₂@GO NPs) by ultrasonic methodology (UZ SONOPULS HD 3400 Ultrasonic homogenizer) with the total power of 400 W and the (frequency of 20 kHz; 140 W/dm³). The formation of as-prepared SnO₂@GO NPs and its surface morphology were scrutinized over XRD, XPS, TEM, and FESEM. Besides, the sonochemically prepared SnO₂@GO NPs were employed for the determination of environmental hazardous mercury (Hg). As a result, the modified electrode acquired a very low-level detection limit of 1.2 nM with a wider range of 0.01–10.41-µM and 14.52–225.4-µM for the detection of Hg. Finally, the practical applicability of SnO₂@GO NPs in spiked human blood serum and tuna fish samples shows appreciable found and recovery values..     

Omeg@Silica: Entrapment and Stabilization of Sustainably Sourced Fish Oil

Fish oil rich in long-chain polyunsaturated fatty acids, vitamin D₃ and carotenoid pigments have been sustainably extracted from anchovy fillet leftovers using biobased limonene. The oil is conveniently stabilized by adsorption on periodic mesoporous silicas. The simplicity of the process, the high load of fish oil, and the biocompatible nature of mesoporous silica support numerous forthcoming applications of this new class of “Omeg@Silica” materials.     

Mineralization of Phosphorylated Fish Skin Collagen/Mangosteen Scaffolds as Potential Materials for Bone Tissue Regeneration

In this study, a potential hard tissue substitute was mimicked using collagen/mangosteen porous scaffolds. Collagen was extracted from Tilapia fish skin and mangosteen from the waste peel of the respective fruit. Sodium trimetaphosphate was used for the phosphorylation of these scaffolds to improve the nucleation sites for the mineralization process. Phosphate groups were incorporated in the collagen structure as confirmed by their attenuated total reflection Fourier transform infrared (ATR-FTIR) bands. The phosphorylation and mangosteen addition increased the thermal stability of the collagen triple helix structure, as demonstrated by differential scanning calorimetry (DSC) and thermogravimetry (TGA) characterizations. Mineralization was successfully achieved, and the presence of calcium phosphate was visualized by scanning electron microscopy (SEM). Nevertheless, the porous structure was maintained, which is an essential characteristic for the desired application. The deposited mineral was amorphous calcium phosphate, as confirmed by energy dispersive X-ray spectroscopy (EDX) results.