舟山群岛新区海产品中甲醛含量分析

应用高效液相色谱一紫外检测法分析了购至舟山国际水产城和沈家门东河市场的海产品中的甲醛。结果显示：不同市场购买的同种海产品中甲醛含量相差不明显,而不同种类的海产品中甲醛的含量差别巨大,其中龙头鱼甲醛含量最高达96．7mg／kg,大部分样品中甲醛含量小于5．0mg／kg,海鳗甲醛则未检出。     

食用海产品中亚硝酸盐含量的分析

根据食品中亚硝酸盐测定的国家标准,针对食用海产品的特点,应用分光光度法,对海虾皮、海蜒、淡菜干、海虾米、海带、海蜇、紫菜等十多种海产品进行检测,并对检测数据进行统计分析,得出上述海产品中亚硝酸盐的含量情况。结果表明:海虾皮、凤尾鱼干、对虾干中亚硝酸盐含量相对偏高,已超过国家标准GB2762—2005中鱼肉的限量指标(3 mg/kg),但仍低于上述国标中酱腌菜的限值(20 mg/kg)和GB2760—2011中腌腊肉制品类的限量指标(30 mg/kg);正规渠道经销的大部分海产品亚硝酸盐含量低于国家标准允许的范围。     

舟山加工海产品中无机砷含量分析及评价

应用氢化物发生-原子荧光法分析了购自舟山南珍菜场和超市的加工海产品中的无机砷。结果显示：超市购买的海产品中无机砷含量普遍较高,其中香烤小黄鱼中含量高达1.52 mg/kg,超出国家规定的限量标准;以含量最高香烤小黄鱼为例,按照海产品50（克/标准人日）的消费量,计算无机砷的摄入量为每人每日76.2μg,没有超出粮农组织/世界卫生组织食品添加剂联合专家委员会（JECFA）规定的每人每日0.129mg的限量,每日食用85g香烤小黄鱼以内不会造成毒性危害。     

毛细管气相色谱法测定进口鱼油保健品中EPA、DHA含量

用Ｖ（苯）：Ｖ（石油醚）＝１：１的混合溶剂溶解鱼油,加入２ｍＬ０．４ｍｏｌ／Ｌ氢氧化钾甲醇溶液,室温静置１０ｍｉｎ。加入蒸馏水使全部有机层升至瓶颈上部,上清液注入气相色谱仪分析。分离柱采用交联ＰＣ－ＷＡＸ－５７ＣＢ（５０ｍ×０．２５ｍｍ×０．２μｍ）毛细管色谱柱;分流进样;载气：Ｈｅ;线速度：８０ｃｍ／ｍｉｎ;分流进样,分流比：１：４０;汽化室温度：２２０℃;柱室温度：４０℃恒温２ｍｉｎ,以２０℃／ｍｉｎ升温至１６０℃,再以２℃／ｍｉｎ升温至２００℃恒温１５ｍｉｎ,以１℃／ｍｉｎ升温至２２５℃。检测器：ＦＩＤ,２５０℃;Ｃ－Ｒ４Ａ色谱专用数据处理打印机进行数据处理。采用内标法定量,以Ｃ２１：０脂肪酸甲酯为内标;ＥＰＡ和ＤＨＡ甲酯对内标Ｃ２１：０甲酯的ＲＲＦ分别为１．１６５±０．０１８和１．１８７±０．０２３;重复性试验：ＳＤ＜５％。经对１２份实际样品测定,结果可靠。     

火焰原子吸收法测定海产品中锶含量

建立了空气-乙炔火焰原子吸收分光光度法(FAAS)测定海产品中微量元素锶含量的方法体系.该方法灵敏度高、选择性强,成为微量金属元素锶快速、方便的分析方法.     

毛细管气相色谱法测定鱼油脂肪乳注射液中DHA和EPA的含量

采用直接进样毛细管气相色谱法测定鱼油脂肪乳注射液中DHA和EPA的含量,色谱柱为PEG-20M毛细管柱,柱温采用程序升温,载气为氦气,流速0.5 mL/min,采用FID检测器,温度为280℃,进样口温度300℃,分流比5∶1,进样量1μL。结果表明,DHA甲酯及EPA甲酯浓度分别为0.197～0.690 g/L 0,.208～0.743 g/L时线性关系良好r,分别为0.999 50,.998 4;平均回收率分别为99.99%9,9.41%,RSD分别为0.52%,0.47%。该法简便、准确,重现性好,可用于鱼油脂肪乳注射液中DHA和EPA的含量测定。     

秦皇岛近岸海域重金属离子含量监测分析

以春季秦皇岛近岸海域东浴场、西浴场、汤河三个采样点的海水为样本,采用石墨炉原子吸收分光光度法测定海水中重金属离子铬、铜、铅、镍的含量。结果表明:秦皇岛近岸海域铬离子浓度范围为0.048～2.225 ng/mL;铜离子浓度范围为10.713～10.756 ng/mL;铅离子浓度范围为4.140～32.779 ng/mL;镍离子浓度范围为13.392～47.692 ng/mL。     

舟山电厂附近海域水体中叶绿素a含量的探讨

对舟山电厂附近海域进行叶绿素a含量的初步调查,并对这该海区叶绿素a含量的变化进行分析,还探讨了叶绿素a含量的分布,以及与环境因子之间的相互关系。调查结果表明,舟山电厂附近海域5、12月两个月叶绿素a含量平均值为1.837μg/L,其中高潮时为1.482μg/L,低潮时为2.193μg/L。分析结果表明,整个调查海区,叶绿素a的含量与海区盐度、水温、光照、气温、透明度等因素密切相关,与高低潮的变化有关。舟山电厂附近海域叶绿素a含量结果表明舟山电厂附近海域水体水质状况良好,未发生水体富营养化。     

福建运行核电厂周边海域海水中锶-90放射性水平分析

本文介绍了福建两座运行核电厂周边海域海水中锶-90放射性水平。监测结果表明：2015年～2022年,福清核电厂和宁德核电厂周边海域海水中锶-90活度浓度与本底调查结果无明显差异,均在本底范围内波动。     

Eicosapentaenoic Acid and Docosahexaenoic Acid Regulate Modified LDL Uptake and Macropinocytosis in Human Macrophages

There is evidence that long chain n-3 PUFA (such as from fish oils) provide atheroprotection through, in part, changes in macrophage function although it has not been fully determined whether these n-3 PUFA target cellular mechanisms that control macrophage foam cell formation. Therefore, we investigated whether the n-3 PUFA, EPA and DHA, modulate modified low-density lipoprotein (LDL) uptake by human macrophages. The uptake of fluorophore labeled acetylated LDL (AcLDL) and/or oxidized LDL (OxLDL) by THP-1 macrophages and primary human monocyte-derived macrophages were measured by flow cytometry following co-incubation with EPA or DHA in vitro. DHA inhibited both AcLDL and OxLDL uptake in human macrophages whilst EPA reduced AcLDL and increased OxLDL uptake. These effects were only partly explained by changes in the mRNA and protein expression of key scavenger receptors, such as CD36 and scavenger receptor-A, in these cells suggesting the involvement of a scavenger receptor-independent mechanism. EPA and DHA inhibited macropinocytosis, as measured by Lucifer Yellow uptake, in human macrophages and attenuated the expression of Syndecan-4, which has been implicated in the uptake of other modified forms of LDL. EPA and DHA reduced modified LDL uptake by human macrophages through a mechanism that is in part scavenger receptor-independent and may involve inhibition of macropinocytosis and Syndecan-4 expression. This suggests that both EPA and DHA are capable of regulating macrophage foam cell formation and adds to the evidence describing an atheroprotective role for n-3 PUFA, implicating them as potential therapeutic agents for the treatment of clinical atherosclerosis.     

超临界CO_2从小球藻中萃取EPA和DHA的工艺研究

研究采用超临界ＣＯ２从小球藻中萃取ＥＰＡ和ＤＨＡ的最优化工艺条件（Ａ２Ｂ１Ｃ３Ｄ３）,得最高萃取率ＥＰＡ为８９．７％、ＤＨＡ为８８．１％,该法比溶剂法优越,为开发和综合利用海藻资源开辟了新的途径     

超临界CO2从螺旋藻中萃取EPA和DHA工艺研究

研究采用超临界ＣＯ２从螺旋藻中萃取ＥＰＡ和ＤＨＡ的最优化工艺条件，得最高萃取率ＥＰＡ为９３％，ＤＨＡ为８９．３％，该法比溶剂法优越，为开发和综合利用海藻资源开辟了新的应用途径。     

Stearidonic Acid Increases the Red Blood Cell and Heart Eicosapentaenoic Acid Content in Dogs

Plant sources of omega-3 fatty acids (FA) are needed that can materially raise tissue levels of long-chain omega-3 FA [i.e., eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 20:6n-3)]. Stearidonic acid (SDA; 18:4n-3) is the delta-6 desaturase product of alpha-linolenic acid (ALA; 18:3n-3), and when fed to humans, increases red blood cell (RBC) content of EPA to a greater extent than does ALA. This study was undertaken to determine the dose-dependence and time course of the increase in the EPA and DHA content of the heart and RBC in dogs. Adult male Beagles were fed 21, 64, or 193 mg/kg of SDA in in their food daily for up to 12 weeks. Positive and negative controls were given EPA (43 mg/kg) or high oleic acid sunflower oil, respectively. The baseline EPA content of RBC was 0.38 ± 0.03% which increased (P < 0.01) in a dose-dependent manner, with the high dose of SDA and EPA achieving levels of 1.33 ± 0.26 and 1.55. ± 0.28%, respectively. In the heart, the content of EPA rose from 0.06 ± 0.01 to 1.24 ± 0.22% in the EPA group and to 0.81 ± 0.32% in the high SDA group (both P < 0.01). In both tissues, DHA did not change. Compared to dietary EPA, SDA was 20–23% as efficient in raising tissue EPA levels. In conclusion, SDA supplementation increased the EPA content of RBC and heart and may have utility as a plant-based source of omega-3 FA.     

超临界CO_2从南海翡翠贻贝中萃取EPA和DHA的研究

用超临界ＣＯ２对南海翡翠贻贝中萃取二十碳五烯酸（ＥＰＡ）和二十二碳六烯酸（ＤＨＡ）工艺进行了研究,得出其最佳工艺条件为：压力３５ＭＰａ,温度３５℃,ＣＯ２用量２ｍｌ／ｇ料,尿素用量为乙酯量的１０％。乙酯的萃取率达到６１．５％。ＥＰＡ和ＤＨＡ乙酯总含量（ｗ）达到２８３２％。     

The Relationship between the Refractive Index of Fish Oils and their Content of Eicosapentaenoic Acid (EPA), Docosahexaenoic Acid (DHA) and Total Polyunsaturated Fatty Acids (PUFA)

Highly significant correlations were found to exist between the refractive index of fish oils and their content of eicosapentaenoic acid, the sum of eicosapentaenoic and docosahexaenoic acid and the total polyunsaturated fatty acids. The refractive index of a fish oil can be used therefore as an indicator of the content of the abovementioned fatty acids.     

Eicosapentaenoic (EPA) and Docosahexaenoic (DHA) Acid Differentially Modulate Rat Neutrophil Function In Vitro

Fish oils are used as therapeutic agents in chronic inflammatory diseases. The omega-3 fatty acids (FA) found in these oils are mainly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. The anti-inflammatory properties of fish oils are attributed to both omega-3 fatty acids. However, it is unknown whether such effects are due to either EPA or DHA. In this study, the effects of EPA and DHA on rat neutrophil function in vitro were compared. Both EPA and DHA increased the production of H₂O₂ when cells were stimulated or not with lipopolysaccharides (LPS). However, EPA was more potent than DHA in triggering an increase in superoxide release by cells in the basal condition or when stimulated with phorbol myristate acetate (PMA) or zymosan. Only DHA increased the phagocytic capacity and fungicidal activity of neutrophils. Both FA increased the release of tumor necrosis factor-α (TNF-α) in nonstimulated cells, but only EPA increased the production of cytokine-inducing neutrophil chemoattractant-2 (CINC-2) in the absence or presence of LPS, whereas production of interleukin-1 beta (IL-1β) was only increased by DHA in the presence of LPS. In addition, there was no alteration in the production of nitric oxide. In conclusion, we show herein that EPA and DHA can differently modulate aspects of the neutrophil response, which may be relevant for the development of therapies rich in one or other FA depending on the effect required.     

Low Docosahexaenoic Acid Content in Plasma Phospholipids is Associated with Increased Non-alcoholic Fatty Liver Disease in China

A large proportion of the Chinese population is now at risk of non-alcoholic fatty liver disease (NAFLD). We aimed to investigate the relationship between plasma phospholipids (PL) fatty acids and the risk of NAFLD. One hundred NAFLD patients and 100 healthy subjects were recruited in Hangzhou, China. Plasma PL and selected biochemical and hematological parameters were analyzed by using standard methods. Stepwise logistic regression was used to identify independent risk factors of NAFLD. Plasma PL total saturated fatty acid (SFA), C20:3n-6, serum alanine aminotransferase, high-density lipoprotein cholesterol, and body mass index were independent risk factors of NAFLD. The risk of NAFLD was significantly increased with higher quartiles of plasma PL total SFA (P for trend = 0.028) and C20:3n-6 (P for trend <0.001); plasma PL docosahexaenoic acid (C22:6n-3) was significantly lower in NAFLD patients than in controls (P = 0.032) and the OR of NAFLD in the highest quartile of C22:6n-3 was 0.41 (95 % CI = 0.17-0.97) compared with the lowest quartile. In conclusion, plasma PL total SFA and C20:3n-6 are positively correlated with the risk of NAFLD, while C22:6n-3 is negatively correlated with the risk of NAFLD.     

An Efficient Methodology for the Preparation of Alkoxyglycerols Rich in Conjugated Linoleic Acid and Eicosapentaenoic Acid

Saponification of a raffinate obtained by supercritical fluid fractionation of shark liver oil was utilized for the production of an unsaponifiable fraction enriched in nonesterified alkoxyglycerols. Re-esterification of the alkoxyglycerols produced with conjugated linoleic acid (CLA) and eicosapentaenoic acid in the presence of Candida antarctica lipase B was then studied. High yields (>90%) of diesterified alkoxyglycerols were obtained via esterification and transesterification with CLA, their respective ethyl ester, and eicosapentaenoic ethyl ester. The effect of a continuous purge stream of nitrogen on the kinetics of the reactions was also evaluated.