鱼油多烯脂肪酸乙酯的NMR表征

利用^1H、^13C核磁共振波谱,对鱼油多烯脂肪酸乙酯的结构进行了表征,并通过二维H－^1H相关谱（COSY）和^1H-^13C化学位移相关谱（HETCOR）对各共振峰进行了指认。     

The antioxidant power of horseradish,Armoracia rusticana,underlies antimicrobial and antiradical effects,exerted in vitro

Abstract

Armoracia rusticana (AR) was tested for antimicrobial and antioxidants power. The compound demonstrated to inhibit fish pathogens such as Vibrio anguillarum, V. harvey, V. alginolyticus, Aeromonas hydrophila, A. salmonicida, Photobacterium damselae subspecie piscicida, Tenacibaculum marinum and Pseudomonas anguilliseptica,. The total phenolic content and the reducing power resulted higher in the water extract of AR, respect to the hydroalcoolic. In vitro test demonstrated that AR significantly protect cells against death, induced by oxidative stress.     

Use of Sea Fennel as a Natural Ingredient of Edible Films for Extending the Shelf Life of Fresh Fish Burgers

The growing interest from consumers toward healthy and nutritious products and their benefits for health has increased the consumption of whole and processed fish. One of the main problems of fish is the short shelf life, especially when it is processed as in the case of burgers. The use of edible coating is an interesting strategy to extend the quality and safety of the product, reducing the need for artificial preservatives. This study evaluated the use of chitosan-based edible film formulated with sea fennel plant and sea fennel extracts. The analyses showed than the use of edible film extended the shelf life of fish burgers regardless of the incorporation of sea fennel mainly associated to the gas barrier properties and selective permeability of the film applied to the fish surface. The incorporation of sea fennel in the films did not produce any antimicrobial enhancement, although sea fennel (mostly extract) produced a better pH and enhanced the antioxidant properties and lipid oxidation of fish burgers. However, sensory analyses showed than fish burgers coated with sea fennel film plant had better acceptability than those with sea fennel extracts, probably due to the better odour and colour of the whole plant during storage. The study showed that the use of sea fennel plant at 12.5% extended the shelf life of fish burgers using a safe and clean label strategy.     

An Open Vessel,Pulse-Microwave Technique for Wet Ashing of Metal-Contaminated Animal Tissues

Abstract

Wet ashing of whole fish arid standard mammalian liver samples for metal determinations is effectively achieved through low power pulse microwave treatment using a domestic grade microwave oven. The reaction is carried out in an open Erlenmeyer flask while held within a much larger sealed container. The latter may be any inexpensive vessel that is microwave proof. The power setting is approximately 70 watts. The oven is programmed to deliver microwaves for 10 seconds every three minutes for a total of 19 minutes. Efficiency of recovery is generally within 10% of the known amounts. The pulse microwave protocol avoids the high temperatures and pressures that create the risk of explosions.     

Trace Analysis of Lead and Copper Ions in Fish Tissue Using Paste Electrodes

Abstract

DNA was immobilized onto a carbon nanotube surface through cyclic voltammetry, in which paste electrode (PE) was subjected to lead and copper trace ion analysis. Optimized conditions for square‐wave stripping voltammetry were then searched. The results indicated three other linear working ranges—3–21 mg l^?1, 2–16 µg l^?1, and 3–17 ng l^?1 Pb(II) Cu(II)—within an accumulation time of 190 s in 0.1‐M ammonium phosphate electrolyte solutions of pH 10.0. At the optimized conditions, the detection limit (S/N) was pegged at 0.4 ng l^?1 (1.93×10^?12 M Pb(II) and 6.29×10^?12 M Cu(II)). And the relative standard deviation at 10 mg l^?1 Pb(II) and Cu(II) was a 0.074 and 0.069% precision, in 15 measurements. The method can be applied to assays of fish tissue.     

高效液相色谱法测定淡水鱼肝脏中维生素A_1和A_2

建立了用高效液相色谱法同时测定淡水鱼肝脏中VA_1和VA_2的方法。以μ-Porasil 3.9mm i.d.×150mm为色谱柱,混合溶剂(正己烷:乙醚=87:13)为流动相,采用紫外350mm,荧光,Ex 325nm、Em480nm双道检测,VA_1、VA_2的保留时间分别为26.25min和28.00min。采用不同波长条件下的紫外吸收特性对VA_2予以定性,以VA_1为内标物对VA_2予以定量。实验分析了几种淡水鱼肝脏中的VA_1和VA_2的含量。     

基于缩硫醛脱保护机制的比例计量型Hg~(2+)荧光探针及其斑马鱼活体造影应用

利用汞离子特异性诱导缩硫醛脱保护,引发分子内电荷转移发生改变的机制,设计合成了一种新型的激发型比例计量汞离子荧光探针.该探针在与汞离子结合后其最大激发波长由410 nm红移至485 nm,两个波长下的荧光强比值(F485/F410)由0.06增长至5.02.同时该探针对汞离子表现出了良好的比例计量响应选择性和较快的响应速度,并且检测限低于美国环境保护组织的饮用水标准.共聚焦造影研究发现,该探针可以应用于活细胞及5天龄斑马鱼幼体中的汞离子的检测.利用该性质对Hg2+在斑马鱼体内分布及毒性进行了初步的研究.     

Usage of Biogenic Apatite (Fish Bones) on Removal of Basic Fuchsin Dye from Aqueous Solution

The contamination with toxic dyes is the most important problem facing all over the world for water sources, environment and living beings. Therefore, in present study, the removal of fuchsin dye from aqueous environment was investigated using fish bones as source of biogenic apatite to the best removal efficiency. The removal efficiency of the adsorbent was investigated as a function of contact time and initial dye concentration. The highest removal capacity was found to 14.75 mg/g. The experimental data generally exhibit a good compliance with the pseudo-second-order equation. Langmuir and Freundlich models were also applied to experimental equilibrium data to find the best adsorption isotherm. Weber-Morris and Urano-Tachikawa models were used to calculate diffusion constants. The results were showed that fish bones can be effectively used as a sorbent for the removal of basic dyes from aqueous solutions.     

毛细管气相色谱法测定鱼油食品中的脂肪酸DHA,EPA

采用毛细管气相色谱法测定鱼油中DHA和EPA的含量,色谱柱为DB–WAX型毛细管柱(30 m×0.530mm,1.00μm),柱温采用程序升温,载气为氮气,流速15 mL/min,FID检测器,温度为300℃,进样口温度260℃,分流比为10∶1,进样量为1μL。DHA及EPA的质量浓度(X)分别在0.25~20.0,0.125~10.0 mg/mL范围内与色谱峰面积(Y)呈良好的线性关系,线性方程分别为Y=905417X+6060.6,Y=887335X+4463.6,线性相关系数r均为0.9999,平均回收率分别为97.8%,96.1%,相对标准偏差小于3%(n=6)。该方法简便、重现性好,可用于鱼油中DHA和EPA含量测定。     

Combining ultrasound‐assisted extraction and vortex‐assisted liquid–liquid microextraction for the sensitive assessment of aflatoxins in aquaculture fish species

Although aflatoxins contamination in feedstuff is a well‐known problem, and hence these residues are controlled in poultry products, there is scarce information regarding the presence of these toxic substances in aquaculture fish, facilities that use several feedstuff for fish breeding. A simple, rapid, and sensitive method has been therefore developed for aflatoxins (B1, B2, G1, and G2) assessment in aquaculture products by combining ultrasound probe‐assisted extraction and vortex‐assisted liquid–liquid microextraction as a sample pretreatment, and high‐performance liquid chromatography‐tandem mass spectrometry as a separation/detection system. Aflatoxins were extracted from fish flesh/liver with a 60:40 acetonitrile/aqueous phosphate buffer (pH 7.0) mixture before preconcentration and clean‐up by vortex‐assisted liquid–liquid microextraction under the following optimized conditions: 5.0 mL of fish extract at pH 7.0 and NaCl at 0.5% (w/v), 400 μL of chloroform as extracting solvent, and vortex shaking at 2000 rpm for 1 min. The proposed method is shown to be precise and accurate, and the limit of quantitations (from 0.20 to 1.10 μg kg^?1) were lower than the value established by the European Commission Regulation for aflatoxins in foodstuff. Results have shown that fish flesh is free of aflatoxins, but aflatoxins B2 and G1 were quantified in fish liver.