冬、夏季6种经济贝类脂肪酸组成

测定和比较了广东湛江地区6种常见经济贝类冬、夏季19种主要脂肪酸组成,探讨了冬、夏2季气候变化对贝类脂肪酸组成的影响和相应的脂肪酸营养价值.结果表明,检测的6种海洋贝类冬、夏季总脂含量分别为(0.11±0.01)%～(0.19±0.01)%,(0.15±0.00)%～(0.45±0.04)%;饱和脂肪酸(SFA)分别为35.15%～47.29%,41.96%～45.99%;单不饱和脂肪酸(MUFA)分别为9.47%～17.68%,13.62%～18.04%;多不饱和脂肪酸(PUFA)分别为39.35%～48.56%,36.25%～43.15%.通过方差分析,6种贝类冬季SFA、MUFA和PUFA的含量均比夏季高,且具有显著差异;冬季的总脂含量虽然比夏季高,但差异不显著.     

虾夷扇贝二倍体与三倍体脂肪酸组成的比较

采用毛细管色谱柱对虾夷扇贝二倍体与三倍体的脂肪酸组成进行了检测。结果表明 :①两者闭壳肌和外套膜的脂肪酸组成相似 ,特征为多烯酸 (PUFA) >饱和脂肪酸 (SFA) >单烯酸 (MUFA) ,PUFA以n 3系列为主 ,主要脂肪酸为 2 2∶6n 3(2 3.9%～ 2 8.9% )、2 0∶5n 3(17.6 %～ 2 0 .6 % )、16∶0 (11.0 %～ 19.4 % )、18∶0 (7.3%～8.1% )、2 0∶4n 6 (2 .8%～ 5 .5 % ) ;②生殖腺的脂肪酸种类相似 ,但两者多数脂肪酸的含量差异显著 ,其中三倍体的SFA和MUFA含量显著高于二倍体 (P <0 .0 1) ,而PUFA含量显著低于二倍体 (P <0 .0 1)。     

不同食物条件下蚤状溞的脂肪酸组成比较研究

在Banta液(牛粪1.5 g 干稻草2 g 沃土20 g 水1000 ml)、酵母、小球藻三种培养条件下,比较研究了蚤状的脂肪酸组成。用GC/MS法分析后结果表明:它们的总脂量变化不大,依次为5.23%、5.46%和6.01%。共检测到15种脂肪酸,其中饱和脂肪酸(SFA)5种,单不饱和脂肪酸(MUFA)4种,多不饱和脂肪酸(PUFA)6种。蚤状以小球藻培养条件下的C 20∶5(EPA)和C 18∶3的含量最高,PUFA占总脂肪酸的34.79%;Banta液组的SFA含量最高,为53.89%;面包酵母组的MUFA含量最高,达60.65%,且富含C 16∶1(n-7)和C 18∶1(n-9),这两种不饱和脂肪酸约占总脂肪酸的56.73%。EPA的含量以小球藻组最高,为14.43%,与自然环境中蚤状的含量相近。酵母组最低,为2.05%。蚤状和其它饵料生物一样,其脂肪酸组成主要随食物特点而变化,也决定于其本身的吸收与合成能力。     

长荡湖野生中华绒螯蟹肌肉营养成分的分析与评价

为了解长荡湖野生中华绒螯蟹(Eriocheir japonica sinensis)肌肉的营养成分,采用国家标准生化测定方法检测了30只蟹肌肉样本中水分、蛋白质、脂肪、灰分、氨基酸和脂肪酸的含量。结果表明,长荡湖野生蟹肌肉的水分含量为78.26%、蛋白质含量为13.00%、脂肪含量为0.62%、灰分含量为1.91%。氨基酸检测中共测出17种氨基酸,谷氨酸含量最高,半胱氨酸含量最低,总量(TAA)为每100g含16.14 g。其中,4种鲜味氨基酸(DAA)占氨基酸总量的40.15%;7种必需氨基酸(EAA)和10种非必需氨基酸(NEAA)分别占氨基酸总量的33.84%和66.16%,必需氨基酸指数(EAAI)值为102.71,符合优质蛋白源的标准。脂肪酸检测中共测出饱和脂肪酸(SFA)5种、单不饱和脂肪酸(MUFA)5种和多不饱和脂肪酸(PUFA)7种。脂肪酸含量SFA∶MUFA∶PUFA为1∶1.2∶2.3;PUFA/SFA为2.3。长荡湖野生蟹可作为优质蛋白来源,对人体具有一定的营养补充和保健作用,同时也可作为中华绒螯蟹新品种选育的优质亲本。     

基于脂肪酸分析的太平洋黄鳍金枪鱼营养生态位研究

黄鳍金枪鱼(Thunnus albacares)是生态系统中的顶级捕食者, 是海洋生态系统能量流动及物质循环的重要一环。为研究太平洋黄鳍金枪鱼在个体发育过程中的摄食变化以及不同海域营养生态位差异, 根据 2019 年东太平洋和 2021 年中西太平洋海域金枪鱼渔船采集的黄鳍金枪鱼样本, 对其肌肉的脂肪酸组成及特征进行了分析研究。结果显示, 黄鳍金枪鱼肌肉检测出 34 种脂肪酸, 包括 16 种饱和脂肪酸(SFA), 8 种单不饱和脂肪酸(MUFA), 10 种多不饱和脂肪酸(PUFA)。黄鳍金枪鱼肌肉脂肪酸中 SFA 含量与 PUFA 含量呈负相关, MUFA 含量与 PUFA 含量呈正相关。SFA 含量与叉长呈显著负相关, MUFA、PUFA 含量与叉长呈显著正相关。中西太平洋和东太平洋黄鳍金枪鱼肌肉脂肪酸含量存在差异, 两海域之间脂肪酸组成平均不相似性为 18.85%, 主要差异来自 n-3 系列多不饱和脂肪酸(n-3 PUFA)、SFA、PUFA、C22∶6n3 (DHA)、Cl6∶0、Cl8∶1n9、MUFA、C22∶6n3/C20∶5n3 (DHA/EPA)、 C18∶0、n-6 系列多不饱和脂肪酸(n-6 PUFA)。主成分分析显示, 黄鳍金枪鱼的营养级越高, 肉食性越高, 以甲藻和硅藻为食源的生物对黄鳍金枪鱼的能量来源贡献越大。相反, 营养级越低的黄鳍金枪鱼主要摄食以细菌、陆地植物和植食性桡足类为食源的生物。主成分回归表明, 黄鳍金枪鱼随叉长增大, 其营养级增加, 肉食性提高, 食性逐渐由以甲壳类和头足类向虾和硬骨鱼等富含多种特征脂肪酸的生物转变。东太平洋黄鳍金枪鱼较中西太平洋肉食性更强, 营养级更高, 甲壳类对其能量贡献更大。     

锈斑蟳肌肉氨基酸和脂肪酸组成分析及营养品质评价

测定了锈斑蟳(Charybdis feriatus)肌肉的氨基酸含量与脂肪酸组成,对其氨基酸含量和脂肪酸组成进行了分析和评价。结果显示,锈斑蟳肌肉干样中共检测出包括牛磺酸在内的19种氨基酸,组成蛋白质的氨基酸总含量为肌肉干重的75.36%,其中,8种必需氨基酸(EAA)的总量为25.41%,占氨基酸(AA)总量的33.73%,非必需氨基酸(NEAA)总量为40.91%,而必需氨基酸与非必需氨基酸的比值(EAA/NEAA)为62.13%;肌肉中4种鲜味氨基酸的含量为28.84%,占氨基酸总量的38.28%;锈斑蟳肌肉中检测出了12种脂肪酸,其中,饱和脂肪酸(SFA)的含量为38.04%,单不饱和脂肪酸(MUFA)的含量为31.58%,多不饱和脂肪酸(PUFA)的含量为29.80%,多不饱和脂肪酸与饱和脂肪酸比值(PUFA/SFA)为0.78,n-3 PUFA与n-6PUFA的比值达到了17.75,多不饱和脂肪酸中EPA和DHA两者的含量达到了20.24%。结果表明,锈斑蟳肌肉中必需氨基酸、鲜味氨基酸含量与不饱和脂肪酸比例较高,具有较高的营养保健价值。     

菊黄东方鲀发育早期的脂肪酸组成变化

采用生化分析手段对菊黄东方鲀的未受精卵、胚胎(出膜前,受精后80~85 h)、初孵仔鱼(0日龄)、开口前仔鱼(3日龄)的脂肪酸组成和含量进行了检测和分析。结果显示,菊黄东方鲀卵和鱼苗的水分含量随着个体发育出现升高趋势,而鱼苗总脂含量随着个体发育显著下降。各发育阶段的干样中检出8种饱和脂肪酸(SFA)、7种单不饱和脂肪酸(MUFA)和12种多不饱和脂肪酸(PUFA)。菊黄东方鲀未受精卵脂肪酸组成与其亲本卵巢非常相似;胚胎期的脂肪酸利用率高低顺序为SFA(15.08%)、MUFA(14.46%)、n6PUFA(10.20%)和n3PUFA(0.19%),以C16:0、C16:1、C18:1n9c和C18:2n6c为主要能量来源,n3PUFA被优先保存,特别是DHA得到完全保留;孵化后,在内源性营养阶段,仔鱼对n3PUFA利用迅速上升,仔鱼开口前的脂肪酸利用率高低顺序与胚胎期正好相反:n3PUFA(19.60%)、n6PUFA(16.98%)、SFA(13.50%)和MUFA(13.01%),以C18:2n6c、C22:5n3(DPA)、C20:5n3(EPA)、C22:6n3(DHA)、C18:1n9c和C16:0为主要能量来源,其中仔鱼对DHA实际利用量为最高(14.44 mg/g),仔鱼在开口前期n3PUFA(特别是DHA)被大量利用消耗。研究表明,菊黄东方鲀仔鱼发育需要消耗大量的n3PUFA(特别是DHA和EPA),并建议在菊黄东方鲀苗种培育开口阶段及时增加富含EPA和DHA饵料的投喂量,如海水的轮虫、藻类强化过的卤虫幼体,缓解苗种开口阶段成活率低下的问题。     

雌性成体点篮子鱼不同组织的脂肪酸组成分析

测定和比较了性腺发育至Ⅲ期的雌性成体点篮子鱼肌肉、肝脏和卵巢组织中总脂含量及其脂肪酸组成。结果表明:(1)肌肉、肝脏和卵巢中的总脂含量分别为(2.79±0.15)%、(12.78±1.30)%和(2.85±0.17)%。肌肉与卵巢间总脂含量差异不显著(P>0.05),肝脏总脂含量约为肌肉和卵巢总脂含量的6倍,呈显著性差异(P<0.05);(2)肝脏中SFA总量明显高于肌肉和卵巢,3种组织中SFA含量呈显著性差异(P<0.05)。单不饱和脂肪酸(MUFA)中,C18∶1ω9 c1(顺式)在3种组织中含量最高,肌肉、肝脏和卵巢中的含量分别为21.86%、23.66%和23.96%,肝脏与卵巢间无显著差异(P>0.05),而与肌肉间差异显著(P<0.05);多不饱和脂肪酸(PUFA)、3PUFA和6PUFA在卵巢中含量最高,其次是肌肉,肝脏中含量最低,且三者之间的差异显著(P<0.05)。     

红罗非和福寿鱼雌性亲鱼不同组织脂肪酸组成分析

Folch法提取红罗非鱼(Oreochromis sp.)和福寿鱼(O.mossambicus×O.niloticus)雌亲鱼不同组织(肌肉、肝胰脏和卵巢)中的脂质,GC法分析脂肪酸组成。结果显示,红罗非鱼和福寿鱼卵巢中总脂含量分别占湿重的16.16%和10.20%,显著高于肝胰脏中的总脂含量(P<0.05),而肝胰脏中的总脂含量又显著高于肌肉(P<0.05)。2种鱼肌肉、肝胰脏和卵巢中共检出18种脂肪酸,主要饱和脂肪酸(SFA)是C14:0、C16:0和C18:0,主要单不饱和脂肪酸(MUFA)是C16:1和C18:1n-9,主要多不饱和脂肪酸(PUFA)是C18:2n-6、C20:4n-6(ARA)、C20:5n-3(EPA)和C22:6n-3(DHA)。ARA在福寿鱼肌肉中含量最高(9.16%),显著高于2种试验鱼其他组织中的ARA含量。Σ(EPA+DHA)在红罗非鱼的卵巢和福寿鱼的肌肉、肝胰脏和卵巢中含量高于其它组织(5.09%～7.70%),福寿鱼肌肉中最高(7.70%),卵巢中次之(6.97%)。红罗非鱼肌肉、肝胰脏和卵巢中的ΣPUFA含量均低于福寿鱼相应组织。红罗非鱼与福寿鱼各组织之间n-3/n-6比率变化不显著,但均小于1,为0.12～0.41。红罗非鱼的肝胰脏和卵巢中,脂肪酸含量ΣSFA>ΣMUFA>ΣPUFA;红罗非鱼肌肉、福寿鱼肝胰脏和卵巢中,ΣMUFA>ΣSFA>ΣPUFA;福寿鱼肌肉中,ΣSFA>ΣPUFA>ΣMUFA。     

浙江南部近海海洋生物脂肪酸含量及组成分析

为探讨浙江南部近海常见海洋生物脂肪酸的特点, 采集 31 种海洋生物, 包括海鱼类 20 种, 甲壳类 9 种, 头足类 2 种, 每种 3 份样品, 共 93 个样本, 采用 Folch 法提取脂肪酸, 以气相色谱-质谱法测定其脂肪酸构成及含量。 分析不同海洋生物间总脂(TFA)、饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)、多不饱和脂肪酸(PUFA)、n-6 系列多不饱和脂肪酸(n-6 PUFA)、n-3 系列多不饱和脂肪酸(n-3 PUFA)、二十二碳六烯酸(C22:6n3, DHA)和二十碳五烯酸(C20:5n3, EPA)含量的差异。结果显示, 海鱼类、甲壳类和头足类总脂含量范围分别为 18.74~153.90, 24.65~62.81, 37.23~92.18 mg/g; DHA+EPA 含量范围分别为 4.32~38.31, 7.22~22.86, 12.48~49.61 mg/g。浙江南部近海 31 种海洋生物的 n-3 PUFA、EPA 和 DHA 含量均与总脂含量呈正相关(P<0.01), 主要脂肪酸构成具有种属差异, PUFA 和 n-3 PUFA 百分含量与物种食性有关, 摄食浮游植物、底栖藻类的物种高于摄食鱼类等游泳动物的物种。     

Simultaneous Extraction and Fractionation of Fish Oil from Tuna By-Product Using Supercritical Carbon Dioxide (SC-CO2)

ABSTRACT

Fish oil was extracted and simultaneously collected into six fractions based on molecular weight and the chain length of triglycerides in terms of fatty acid constituents without splitting of the triglycerides, using supercritical carbon dioxide (SC-CO₂) at optimized conditions of 40 MPa, 65°C, and a flow rate 3 mL min^?1. In each type of fractionation, the first fraction (F1) was rich in saturated fatty acids (SFA; 52.57 to 61.26%), followed by monounsaturated fatty acids (MUFA; 22.17 to 23.22%) and polyunsaturated fatty acids (PUFA; (0.54 to 20.37%); the sixth fraction (F6) was rich in PUFA (48.93%), followed by MUFA (33.59%) and SFA (13.61%). It was obvious that short-chain fatty acids were extracted at an earlier fraction; therefore, the latter fractions were dominant in long-chain fatty acids, especially MUFA and PUFA. Thus, omega-3 fish oil (last three fractions) was successfully separated to be used as a value-added health product.     

察尔森水库细鳞斜颌鲴营养成分分析及评价

本试验对察尔森水库细鳞斜颌鲴(Plagiognathops microlepis)肌肉营养成分进行了分析及评价。试验采用常规营养成分分析法对细鳞斜颌鲴肌肉一般营养成分、氨基酸组成、脂肪酸组成进行了测定。结果表明:细鳞斜颌鲴肌肉中水分含量为79.31%、粗蛋白含量为16.56%、粗脂肪含量为0.94%、灰分含量为1.13%、总糖含量为0.38%。细鳞斜颌鲴肌肉共检出18种氨基酸,其中必需氨基酸(EAA)8种,非必需氨基酸(NEAA)10种,总氨基酸(TAA)含量为16.28%,EAA含量为6.72%,NEAA含量为9.56%;EAA/TAA(41.29%)及EAA/NEAA(70.32%)均在FAO/WHO推荐值以上。氨基酸评分(AAS)和化学评分(CS)结果是第一限制性氨基酸均为色氨酸(Trp),而第二限制性氨基酸,AAS是苏氨酸(Thr),CS是苯丙氨酸+酪氨酸(Phe+Tyr)。细鳞斜颌鲴肌肉共检出21种脂肪酸,其中7种饱和脂肪酸(SFA)、3种单不饱和脂肪酸(MUFA)、11种多不饱和脂肪酸(PUFA),分别占脂肪酸总量的25.22%、22.02%、37.76%;C20∶5n3(EPA)含量为11.87%,C22∶6n3(DHA)含量为11.55%。从营养分析结果来看,细鳞斜颌鲴是一种营养价值极高的食用鱼类。     

河川沙塘鳢胚胎、仔鱼发育过程中脂类含量及脂肪酸组成的变化

采用生物化学方法测定和分析了河川沙塘鳢(Odontobutis potamophila)胚胎、仔鱼发育过程中脂类的含量及脂肪酸的组成。结果显示,随着胚胎和仔鱼的发育,其总脂的含量呈下降趋势,饱和脂肪酸(SFA)的含量亦呈现出下降趋势,单不饱和脂肪酸(MUFA)的含量在胚胎期保持稳定、在仔鱼期下降,而多不饱和脂肪酸(PUFA)却呈现出不断增长的趋势。在整个胚胎和仔鱼发育过程中,平均含量最高的脂肪酸依次是C16∶0、C18∶1n-9、C18∶0、C16∶1、C22∶6n-3(DHA)和C20∶5n-3(EPA)。结果表明:河川沙塘鳢在胚胎和仔鱼发育过程中有消耗饱和脂肪酸和单不饱和脂肪酸,而保存n-3系列和n-6系列的高度不饱和脂肪酸的趋势,饱和脂肪酸被作为胚胎期能量代谢的主要来源,单不饱和脂肪酸被作为仔鱼期能量代谢的主要来源,而C18∶3n-3(亚麻酸)和C18∶2n-6(亚油酸)被用于合成DHA、EPA和C20∶4n-6(AA)。     

Lipid Changes During Long-Term Storage of Canned Sprat

Lipid changes during canning and 3-years storage of oil and brine canned sprat were studied. Thermal treatment during precooking and sterilization produced an increase in free fatty acid content. Secondary oxidation product showed a considerable increase in canned samples after storage time. A significant increase was found by comparing the fluorescence shift measured in both canned samples with cooked fish. The fluorescence compound in both filling media was increased after 3 years. Oil canning affected the sprat fatty acids composition. Results showed the amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and Σω3 significantly decreased in oil canned samples. However, the polyunsaturated fatty acids (PUFA) and Σω6 had the opposite behavior. The latter effect was more marked with increased storage time. Results showed the amount of SFA, MUFA, PUFA, and Σω3 did not alter in brine canned samples. After storage, the amount of MUFA and Σω3 decreased, and the content of SFA increased in brine canned samples.     

The Effects of Natural Antioxidant Extract Isolated from Giant Red Shrimp (Aristaeomorpha foliacea) Shells on Fatty Acid Profiles of Anchovy (Engraulis encrasicolus) During Refrigerated Storage

The aim of the present study was to determine the effects of natural antioxidant extract isolated from the shells of giant red shrimp (Aristaeomorpha foliacea) on the changes in fatty acid profile of anchovy (Engraulis encrasicolus) during refrigerated storage (2.7°C). Total antioxidant activity of shell extract was determined as 45.84%, total phenolic compound as 17.87 mg/100 g shell, and total carotenoid content in shell as 20.31 mg/100 g shell. Total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), and polyunsaturated fatty acid (PUFA) contents in the control group and the group with 0.1% shell extract addition were found to be affected by the duration of storage (p < 0.05). A percentage increase was determined in MUFA content, while decreases were observed in PUFA content. No statistically significant change was detected in SFA, MUFA, and PUFA contents of groups with added butylated hydroxytoluene (BHT) and 0.5% of shell extract (p > 0.05). It was concluded that the extract isolated from shrimp shells could be used during the cold storage of fish fillets instead of synthetic antioxidants.     

Effect of dietary saturated and monounsaturated fatty acids in juvenile barramundi Lates calcarifer

Barramundi (Lates calcarifer), a catadromous teleost of commercial interest, perform well when fed a wide range of dietary oils. However, the range of alternative oils now being explored is typically rich in saturated and monounsaturated fatty acids (SFA and MUFA). In this study, the response of juvenile barramundi (47.0 g per fish initial weight) fed isolipidic and isoenergetic diets with 82 g kg^?1 added oil was tested. The experimental test diets had a 2 : 1 or 1 : 2 ratio of SFA to MUFA (SFA‐D and MUFA‐D, respectively) compared to a control diet (CTRL‐D) fed for 8 weeks. The diets containing mostly olive oil (dietary MUFA‐D) and mostly refined palm oil (dietary SFA‐D) did not impact the growth performance or feed utilization parameters of the barramundi. The in vivo beta‐oxidation activity was consistent with the dietary fatty acid composition, with the most dominant FA being heavily beta‐oxidized. Together, the in vivo whole‐body mass balance of fatty acids showed that n‐3 long‐chain polyunsaturated fatty acids (LC‐PUFA) were most efficiently utilized in the SFA‐D‐ and MUFA‐D‐fed fish. This study provides evidence that additional dietary MUFA and SFA are suitable lipid classes for juvenile barramundi and they are both equally efficient at sparing LC‐PUFA from an oxidative fate.     

An Invasive Shrimp Species,Machrobrachium nipponense,in Anzali Wetland Demonstrated a Potential Source for Commercial Fishing

ABSTRACT

The proximate content, fatty acids composition, and nutritional quality index (NQI) of Macrobrachium nipponense at three habitats in the Anzali wetland in Iran were investigated as a potential source for human consumption. The highest amounts of protein, lipid, ash, and energy contents in muscle of M. nipponense were showed in autumn (non-reproductive season) (p < 0.05). The main monounsaturated fatty acids (MUFA) were oleic acid (C18:1 n9 C, C18:1 ω9 T) and palmitoleic acid (C16:1). Moreover, the main polyunsaturated fatty acids (PUFA) were docosahexaenoic acid (DHA, C22:6 n3), eicosapentaenoic acid (EPA, C20:5n3), arachidonic acid (ARA, C20:4 n6), linoleic acid (LA, C18:2 ω6), and α-linolenic acid (ALA, C18:3 n3). The predominant individual saturated fatty acid (SFA) was palmitic acid (0.07–13.4%), while oleic acid (14.7–26.3%), EPA (3.5–12.7%) and linoleic acid (0.04–14.9%) represented the most abundant individual MUFA and PUFA in M. nipponense. The highest mean value of EPA+DHA (14.0), n3/n6 (1.02), ΣMUFA/ΣSFA (1.05), ΣPUFA/ΣSFA (1.04), and EPA/DHA (3.8) ratios in M. nipponense was in autumn. The range of atherogenicity index (AI) and thrombogenicity index (TI) was much lower, from 0.42 to 0.6 and from 0.33 to 0.57, respectively, in terms of season. The results obtained in the present study show that M. nipponense is an excellent nutritional food source in the Anzali wetland.     

黑斑原(鮡)肌肉脂肪酸及无机盐组成特征分析

为探究黑斑原肌肉营养成分,合理开发和保护利用黑斑原种质资源,分析采自西藏自治区日喀则市昂仁县境内(N 29°27′58.72″,E 86°54′36.06″)体质量为(158.92±24.10) g的黑斑原肌肉脂肪酸和无机盐组成成分。试验结果显示,黑斑原肌肉(鲜样)中含有16种脂肪酸,其中总饱和脂肪酸8种,总量为1015.7 mg/kg,单不饱和脂肪酸2种,总量为494.4 mg/kg,多不饱和脂肪酸6种,总量为1148.3 mg/kg,必需脂肪酸含量为108.37 mg/kg,二十碳五烯酸和二十二碳六烯酸含量为960.08 mg/kg。黑斑原肌肉的致动脉粥样硬化指数和血栓形成指数分别为0.40和1.18。黑斑原肌肉中共检出无机盐元素19种,其中K含量最高,为4061.23 mg/kg,V含量最低,为0.01 mg/kg,其中Ca∶P为1∶164,Na∶K为0.33∶1。对黑斑原肌肉中部分无机盐元素进行了风险评估,Zn元素风险指数最大,最大风险指数为16.13%~39.53%,Se元素的风险指数最小,最大风险指数为0.02%~0.03%,所评估的几种无机盐元素风险指数均在安全范围之内。综上,黑斑原肌肉中多不饱和脂肪酸含量丰富,无机盐元素含量丰富,具有较高的食用和保健价值。     

东太平洋不同海区茎柔鱼肌肉脂肪酸组成分析与比较

茎柔鱼(Dosidicus gigas)是一种广泛分布在东太平洋的大洋性头足类,具有重要的经济价值。本研究以捕获自3个作业海区的茎柔鱼为研究对象,对其肌肉脂肪酸含量进行测定、分析和比较。结果显示,各海区茎柔鱼肌肉脂肪酸种类和组成存在显著差异。秘鲁外海样品所含脂肪酸种类最多(共28种),中东太平洋赤道海域样品含有脂肪酸27种,而智利外海样品所含脂肪酸种类最少,只检测出24种。脂肪酸均以多不饱和脂肪酸为主(59.68%~69.28%),其次是饱和脂肪酸(20.71%~27.28%)和单不饱和脂肪酸(10.01%~13.04%)。各海区茎柔鱼肌肉中C16:0、C18:0、C20:1n9、C18:2n6、EPA和DHA含量较高,均占脂肪酸总含量的81%以上。脂肪酸组成的空间异质性主要是由各海区C16:0、C18:2n6、C20:4n6和DHA的含量不同造成的,这种差异可能与各海区海洋环境、食物来源和个体能量需求的差别有关。本研究说明了脂肪酸分析在茎柔鱼食性研究中的潜在作用,对分析不同海区茎柔鱼营养成分和资源合理利用有一定的应用价值。     

Variations in fatty acids composition of pikeperch (Sander lucioperca) liver with respect to gonad maturation

Abstract –  We examined seasonal variations in liver condition factor, total lipid and fatty acid composition of maturing pikeperch ( Sander lucioperca) from Lake Eğirdir, Turkey. The spawning of pikeperch in Eğirdir Lake started in March, continued very fast during May and gradually ended in July as determined by measuring the gonadosomatic index. The total lipid content of male and female liver reached its highest level in September and November (the end of dense feeding period during which temperature decreased sharply), but declined to the lowest level in May (just after spawning). The highest level of liver condition factor was observed in January and March during which gonads mature rapidly. Palmitic acid was the predominant saturated fatty acid (SFA) in female and male liver. The ratio of monounsaturated fatty acids (MUFA) was higher than that of polyunsaturated fatty acids (PUFA) in both sexes. Docosahexaenoic acid (22:6 n -3), eicosopentaenoic acid (20:5 n -3) and arachidonic acid (20:4 n -6) were the predominant PUFA. Seasonal variations in PUFA were more evident than that in other fatty acids. PUFA, especially the n -3 fatty acids ratio, increased to the maximum level during the sharp decreases in temperature (in November). However, the amount of PUFA decreased to the lowest level in reproductive period. The results suggest that the ratio of pikeperch liver fatty acids is influenced by gonad maturation and temperature variations and that pikeperch requires a large amount of PUFA and the n -3 fatty acids for the development of gonads.