两种复海鞘油脂中的脂肪酸成分分析

不饱和脂肪酸尤其是ω-3多不饱和脂肪酸是对人类健康具有重要意义的一类营养成分。对海鞘(Aplidium constellatum)和大洋纵列海鞘(Symplegma oceania)两种复海鞘的油脂类成分进行相对含量分析,发现海鞘(A.constellatum)油脂中含有EPA、DHA两种ω-3 PUFAs,含量分别为19.5%和12.7%,大洋纵列海鞘油脂中EPA、DHA的含量分别为18.2%和7.73%。结果表明,两种海鞘油脂均具有较好的开发前景。     

星座短腹海鞘脂溶性成分的提取工艺

以星座短腹海鞘(Aplidium constellatum)为研究对象,采用正交试验法对其脂溶性成分的提取工艺进行优化。以提取率和类胡萝卜素含量为指标评定工艺的优劣,并通过气相色谱对提取物中二十碳五烯酸(EPA)与二十二碳六烯酸(DHA)进行相对含量分析。结果表明,采用料液比1∶1.5(W/V)、提取时间8 min、溶剂(正丁醇/乙酸乙酯)配比1∶2(V/V)工艺条件最佳。正交试验提取物的总不饱和脂肪酸的相对含量达63.40%~65.00%,其中EPA和DHA总量在15.20%~16.30%。综合2个指标,正交试验法优化星座短腹海鞘脂溶性成分的提取工艺是可行的;利用该提取方法获得的星座短腹海鞘脂溶性提取物中,EPA和DHA两种ω-3多不饱和脂肪酸的相对含量较高,具有很好的开发前景。     

柄海鞘——具有广阔加工前景的资源

本文从食用性和药用性两个方面探讨了柄海鞘（Styela clava）资源的加工价值，并且提出了柄海鞘加工为食品、保健品及药品的思路。食用方面：柄海鞘体内的蛋白质含量丰富；氨基酸种类齐全且组成比例很好，牛黄酸含量很高；多不饱和脂肪酸，包括EPA和DHA的含量较高；矿物质元素尤其是人体必需的微量元素含量很高，食用性强，可开发加工为各种调味料及保健产品。药用方面：柄海鞘体内含有抗菌效果明显的三种抗菌肽Clavanins，Styelins，Clavaspirins，以及其他可用于治疗各种疾病的生理活性物质，而且柄海鞘被囊的粗提物就具有很好的抑瘤效果，药效强，因此将柄海鞘用于开发研制各种药物将会有很好的市场前景。     

不同加工方式的南极大磷虾粉营养品质评价

对3种加工方式的南极大磷虾(Euphausia superba)粉(磷虾粉A为冷冻运回中国,冻干;磷虾粉B为捕捞现场蒸煮加工,未添加抗氧化剂;磷虾粉C为捕捞现场蒸煮加工,添加抗氧化剂)的营养品质进行分析和评价。结果显示,3种磷虾粉中粗蛋白占干物质的质量分数为61.73%~68.48%,氨基酸总量(ΣAA)为51.46%~66.32%,10种鱼虾必需氨基酸总量(ΣEAA)为23.69%~31.78%,多不饱和脂肪酸总量(ΣPUFA)占脂肪酸总量的44.05%~52.74%,EPA和DHA占脂肪酸总量的38.55%~46.38%。其中磷虾粉C的ΣAA、ΣEAA、EAAI值、SRC值、ΣPUFA、EPA和DHA的质量分数均高于磷虾粉A和B。磷虾粉C的粗蛋白质量分数高,氨基酸组成合理,多不饱和脂肪酸丰富,具有最高的营养价值。     

4种狗母鱼科鱼类肌肉脂肪酸分析

在广东湛江海域采集长体蛇鲻、花斑蛇鲻、射狗母鱼和准大头狗母鱼4种狗母鱼科鱼类,用气相色谱法测定肌肉中21种脂肪酸含量。试验结果表明,4种狗母鱼科鱼类的饱和脂肪酸含量在31.14%～42.16%,单不饱和脂肪酸含量在11.73%～21.73%,多不饱和脂肪酸含量达31.64%～55.32%,其中ω-6系和ω-3系脂肪酸分别为4.49%～9.77%和22.61%～45.55%,花斑蛇鲻和射狗母鱼二十碳五烯酸+二十二碳六烯酸含量分别达30.49%和42.32%,这两种鱼具有较高的脂肪酸营养价值。4种狗母鱼科鱼类的主要脂肪酸的相关性分析表明,肉豆蔻酸与棕榈油酸、肉豆蔻酸与油酸、棕榈酸与二十二碳五烯酸(ω-3)、棕榈油酸与油酸、油酸与二十二碳五烯酸(ω-3)呈显著正相关;肉豆蔻酸与花生四烯酸(ω-6)、棕榈油酸与花生四烯酸(ω-6)、肉豆蔻酸与二十二碳六烯酸(ω-3),棕榈油酸与二十二碳六烯酸(ω-3)、油酸与二十二碳六烯酸(ω-3)、二十二碳五烯酸(ω-3)与二十二碳六烯酸(ω-3)呈显著负相关。聚类分析将科内4种狗母鱼科鱼类分为3类(属)。     

南极磷虾油提取方法比较及主要营养成分分析

为探索一种适合工业化生产的磷虾油提取方法,以新鲜南极磷虾为原料,分别采用乙醇一步提取法、丙酮/乙醇一步提取法和乙醇两步提取法提取磷虾油,比较了3种工艺条件下的磷虾油得率,并测定了磷虾油中的主要营养成分。结果表明,10 ℃条件下,采用乙醇两步提取法虾油得率较高,达15.72 %,是一种安全有效的提取方法。经气相色谱法测定,磷虾油中EPA、DHA的含量分别为11.76 %、4.22 %；经UV法测定,磷虾油中虾青素的含量为0.102 %,表明磷虾油是一种高品质的油脂。     

半滑舌鳎不同家系肌肉中脂肪酸含量的分析

为了研究半滑舌鳎(Cynoglossus semilaevis)不同家系肌肉中脂肪酸的组成与含量,并选育出高营养品系的半滑舌鳎家系,用气相色谱法对同一养殖环境中的半滑舌鳎15个不同家系(164个样本)肌肉中的脂肪酸的组成和含量进行了检测和比较分析,同时对高EPA、DHA、EPA+DHA含量的家系进行筛选,并研究了半滑舌鳎性别与EPA、DHA含量的关系。结果表明:(1)15个家系肌肉中脂肪酸种类没有区别,但脂肪酸的组成和含量存在若干差异。其特征均为多不饱和脂肪酸(PUFA)饱和脂肪酸(SFA)单不饱和脂肪酸(MUFA)。PUFA以ω-3系脂肪酸为主,且ω-3系脂肪酸与ω-6系脂肪酸比值达到4.16~5.03,其中的2种重要ω-3系脂肪酸EPA和DHA在15个家系中均具有显著性差异,且DHA含量远大于EPA含量;筛选出了3个高EPA、DHA、EPA+DHA含量家系,分别为F13012、F13023及F13031。(2)EPA的含量与半滑舌鳎性别不具有显著性相关关系。本研究对于选育半滑舌鳎优良品种家系具有重要意义。     

鱼类消费健康风险研究进展

与陆地动物相比,鱼类含有更多的ω-3系列多不饱和脂肪酸(ω-3 PUFA),尤其是DHA(C22∶6ω3)和EPA(C20∶5ω3),其中DHA可以促进婴幼儿神经系统、视觉系统的发育,EPA对于预防心血管系统疾病(CVD)有重要作用。经常食用鱼类有益于人体的健康,但水环境中各种有机的和无机的污染物通过食物链及生物放大作用在鱼体内累积,对人类健康有潜在的威胁。文章综述了PUFA对人体的生理作用,食用鱼类存在的风险,鱼类消费风险评估以及如何平衡食用鱼类的益处和风险。     

杂色蛤软体部营养成分分析及评价

测定分析了杂色蛤软体部的营养成分。结果表明,杂色蛤软体部(鲜样)中水分、粗灰分、粗蛋白和粗脂肪的质量分数分别为82.70%、2.63%、9.63%和0.54%。杂色蛤软体部(干样)中含有18种氨基酸,总量为52.86%,其中必需氨基酸(EAA)总量为21.58%,占氨基酸总量的40.82%,必需氨基酸与非必需氨基酸的比值(WEAA/WNEAA)为88.23%,构成比例符合FAO/WHO规定的优质蛋白质标准,鲜味氨基酸(DAA)总量为18.89%,占氨基酸总量的35.74%。杂色蛤软体部的限制性氨基酸为(甲硫氨酸+胱氨酸)、异亮氨酸和色氨酸,必需氨基酸指数(EAAI)为73.83。脂肪酸中多不饱和脂肪酸(PUFA)占29.74%,其中EPA和DHA共占PUFA的67.82%,ω-3PUFA的含量丰富且明显高于ω-6 PUFA的含量。矿物元素比例合理,微量元素中Fe和Se含量较丰富,维生素中VA、VB2和VB5含量较丰富。表明杂色蛤软体部具有较高的食用价值与保健作用。     

南极磷虾粉营养成分的分析与比较

对两种不同来源的南极磷虾粉营养成分进行了分析和评价,并与进口鱼粉的营养成分进行了比较。结果显示,上海开创远洋渔业有限公司开利轮产南极磷虾粉(磷虾粉S)粗蛋白含量为62.89%,高于辽宁远洋渔业有限公司安兴海轮产南极磷虾粉(磷虾粉D)和进口鱼粉的粗蛋白含量,两种磷虾粉粗蛋白质含量分别达到一级品和二级品指标。磷虾粉S、磷虾粉D和进口鱼粉18种氨基酸总量分别为66.36%、57.19%、67.24%,鲜味氨基酸含量较高分别为24.65%、20.69%和25.25%,8种必需氨基酸含量分别为31.43%、21.74%、25.62%,且磷虾粉S必需氨基酸含量明显高于磷虾粉D和鱼粉,磷虾粉S、磷虾粉D和进口鱼粉三种样品必需氨基酸指数(EAAI)分别为57.83、49.89、57.07;磷虾粉S、磷虾粉D和进口鱼粉三种样品脂肪酸中,多不饱和脂肪酸含量较高分别为43.28%、40.25%、46.58%,且磷虾粉S的EPA与DHA的总量(36.14%)高于磷虾粉D(31.30%)及鱼粉(27.65%)。分析结果表明,南极磷虾粉蛋白含量高,且氨基酸组成符合FAO/WHO推荐的蛋白质理想模式,含有丰富的多不饱和脂肪酸,营养价值较高,具有较大的开发利用前景。     

Can Different Body Tissues of Two Sea Cucumbers Supply a Fair Amount of Omega 3 for Health Benefit?

The lipid content and fatty acids profile of different tissues of Holothuria tubulosa and H. polii were analyzed to assess the suitability of the central Mediterranean species as a potential marine resource for fatty acids, in particular omega-3 polyunsaturated fatty acids (n-3 PUFAs). Simultaneously, their important indices for human health were evaluated. Gonad and respiratory tree had the highest lipid content, while the body had the lowest values. The results showed significant differences between species and among the different portions analyzed. Internal tunic and longitudinal muscle of H. tubulosa exhibited the highest PUFA proportion (55.3 and 46.4%, respectively). Eicosapentaenoic acid (EPA, C20:5n-3) and arachidonic acid (ARA, C20:4n-6) were the most abundant PUFAs in both species, with a favorable n-3/n-6 ratio in all tissues. The atherogenic and thrombogenicity indices and hypocholesterolaemic/hypercholesterolaemic fatty acid ratio suggested the high-quality of this food, similar to the nutritional values of most popular fish.     

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.     

锦江河大眼鳜和斑鳜肌肉中脂肪酸组成的比较

采用气相色谱法测定了贵州锦江河特有鱼类国家级水产种质资源保护区大眼鳜(Siniperca kneri)和斑鳜(S.scherzeri)肌肉的脂肪酸组成。结果显示:大眼鳜肌肉含有24种脂肪酸,斑鳜肌肉含有20种脂肪酸。大眼鳜肌肉中饱和脂肪酸占36.402%,单不饱和脂肪酸占37.160%,多不饱和脂肪酸占26.438%;斑鳜肌肉中饱和脂肪酸占35.263%,单不饱和脂肪酸占30.747%,多不饱和脂肪酸占33.990%。从脂肪酸的组成特征来看,大眼鳜肌肉中必需脂肪酸占9.780%,反式脂肪酸含量为0.210%,ω-6/ω-3比值为0.634,EPA和DHA含量占8.700%;斑鳜肌肉中必需脂肪酸占10.115%,未检出反式脂肪酸,ω-6/ω-3比值为0.676,EPA和DHA含量占12.329%。结果表明,斑鳜肌肉脂肪酸营养价值较大眼鳜更好。     

Fatty acid composition of New Zealand green-lipped mussels, Perna canaliculus: Implications for harvesting for n-3 extracts

Marine bivalves offer a potentially important source of long-chained polyunsaturated fatty acids (PUFA) for human health supplements. Lipid extracts from individual New Zealand green-lipped mussels (NZGLM) were analyzed as fatty acid methyl esters (FAME) by gas chromatography to assess geographical and seasonal differences between large (86 ± 1 mm) male and female and small (44 ± 1 mm) mussels. PUFAs dominated in spring and summer, comprising ∼ 50% of total fatty acids. Moreover, the commercially important n-3 fatty acids, 20:5n-3 (eicosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic acid, DHA) together accounted for 70-79% of total PUFAs in spring and summer. During winter there was a marked decrease in condition and total n-3 PUFAs and a concomitant increase in saturated fatty acids in mussels, suggesting they had already spawned, had increased metabolic demands and limited PUFA-rich phytoplankton as food. While total n-3 content was not significantly different, there were geographical differences in individual n-3 fatty acids. Mussels collected from the cooler waters of Stewart Island had greater levels of 20:5n-3 (EPA), while those collected in Marlborough had greater concentrations of 22:6n-3 (DHA), which was attributed mainly to differences in phytoplankton composition. Total n-3 content and the condition index varied seasonally with greater concentrations of n-3 PUFAs, especially EPA, recorded in large mussels in spring, coincident with spring diatom blooms. Total PUFA levels and condition indices remained high in summer. There was no significant difference in condition indices, total n-3 content, DHA or EPA levels between large male and female mussels. Conversely, large mussels had significantly greater amounts of n-3 PUFAs than small mussels at Marlborough Sounds, while small mussels had marginally greater total n-3 concentrations than large mussels at Stewart Island. Taken together, these results suggest that the NZGLM offers a potentially important source of n-3 PUFAs for human health supplements. Our findings suggest that optimal harvesting conditions occur in spring when mussel condition and n-3 content peak for large mussels. Although DHA and EPA levels varied geographically, total n-3 content was not significantly different between sites, which implies that harvesting mussels for n-3 extracts would be driven more by logistical considerations.     

Effects of dietary lipids on tissue fatty acids profile,growth and reproductive performance of female rice field eel (<Emphasis Type="Italic">Monopterus albus</Emphasis>)

The effects of different lipids on tissue fatty acid profile and reproductive performance in female rice field eel were investigated in this study. Virgin female eels were fed with six diets containing different lipids (diets FO, LO, SO, PO and PL with fish oil, linseed oil, soybean oil, peanut oil and pork lard, respectively; diet APO with arachidonic acid and peanut oil). The results showed that there were positive correlations between the contents of 18:2n-6, 18:3n-3, arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the tissues of eels and those of the corresponding fatty acids in their diets. The specific growth rate of eels fed with diet PO was the lowest and significantly lower than that of FO and SO. Gonad of eels fed with diets PO and PL showed hypogonadism. The long chain polyunsaturated fatty acids (LC-PUFA) can be synthesized by eels, but the quantity was not enough to meet their reproduction requirement completely. The fatty acid desaturation, rather than elongation probably was one of the limiting factors. Addition of proper amount of ARA in diet was favorable to the increase of the hatching rate of fertilized eggs, while EPA and DHA in diet were beneficial to the increase of the survival rate of larva. Both n-3PUFA and a suitable n-6/n-3PUFA ratio were necessary for growth and reproduction of eels.     

Enrichment of C20-22 Polyunsaturated Fatty Acids from Refined Liver Oil of Leafscale Gulper Shark,Centrophorus squamosus

The C_20-22 polyunsaturated fatty acids (C_20-22 PUFAs), mainly eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), were concentrated from the refined liver oil of deep sea leafscale gulper shark, Centrophorus squamosus, by sequential processes of winterization, urea complexation, and argentation chromatography. Winterization at 4°C using acetonitrile as solvent showed significant reduction of the total saturated fatty acid content (12%) with a concomitant increase of polyunsaturated fatty acids (36.3%). The urea complexation process significantly enriched the total polyunsaturated fatty acids (49.5%), with a reduction in saturated fatty acids (83.9%). Silica gel based argentation chromatography further concentrated the esters of C_20-22 PUFA (>99 percent purity). Nuclear Magnetic Resonance spectroscopy was used as a chemical fingerprinting tool to study the enrichment of C_20-22 PUFAs at various stages of the purification process. An increase in the proton signal intensity at the olefinic region (at δ 4–6) and a decrease in the aliphatic signals (at δ 0.5–2) showed that the process successfully enriched the C_20-22 PUFAs.

Abbreviations: PUFA, polyunsaturated fatty acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; FAME, fatty acid methyl esters; SFA, saturated fatty acid; MUFA, monounsaturated fatty acid; NMR, nuclear magnetic resonance; GCMS, gas chromatography mass spectrometry; FFA, free fatty acid.     

A quantitative comparison between diet and body fatty acid composition in wild northern pike (Esox lucius L.)

The fatty acid compositions of wild female northern pike (Esox lucius L.) and their principle prey species were compared to assess the extent to which pike modify the relative abundance of dietary fatty acids during assimilation and to indicate the optimum dietary content of essential fatty acids (EFAs) for pike. Only minor differences existed between the estimated whole body fatty acid composition of pike and diet fatty acid composition as calculated from the contribution of each prey species to the pike's diet. Saturated fatty acids comprised a slightly higher percentage of diet lipids (25% wt) than of pike lipids (21% wt) whereas monounsaturated fatty acids were less abundant in diet lipids (26% wt) than in pike (29% wt). Percentages of total polyunsaturated fatty acids (PUFAs), n - 3 fatty acids, and n - 6 fatty acids were approximately 43, 30, and 13% wt respectively and differed by less than 1% wt between pike and diet lipids. Among individual PUFAs, the largest differences occurred in 20:5 (n-3) and 22:6(n-3) which comprised, on average, 9.6 and 14.7% wt respectively of diet lipids and 5.9 and 18.3% wt respectively of pike lipids. The close similarity in fatty acid composition between pike and their diet suggests that pike may have limited abilities to elongate and desaturate 18 carbon PUFAs and may require specific long chain PUFAs in the diet. The n-3 PUFA content of the pike's natural diet may exceed the minimum EFA requirements of better studied species such as rainbow trout and turbot.     

Beef tallow is suitable as a primary lipid source in juvenile Florida pompano feeds

It is assumed that Florida pompano have dietary EPA (20:5n‐3) and DHA (22:6n‐3) requirements. However, it is unclear whether both are equally important in meeting demand for n‐3 long‐chain polyunsaturated fatty acids (LC‐PUFAs) or whether the requirement(s) can be influenced by other fatty acids. Accordingly, we assessed production performance and tissue composition of juvenile Florida pompano (41.0 ± 0.5 g) fed diets containing fish oil; beef tallow; or beef tallow partially or fully supplemented with EPA, DHA or both. After 8 weeks, no signs of fatty acid deficiency were observed. Although fish performance did not vary significantly among the dietary treatments, fish fed the DHA‐supplemented feeds exhibited numerically superior growth than those fed the other diets. Fillets of fish fed the beef tallow‐based diets contained reduced levels of n‐3 fatty acids and LC‐PUFAs and elevated levels of MUFAs and n‐6 fatty acids, although dietary supplementation with EPA and/or DHA attenuated these effects somewhat. Our results suggest that beef tallow is suitable as a primary lipid source in Florida pompano feeds and n‐3 LC‐PUFA requirements may be met by as little as 4 g/kg EPA and 4 g/kg DHA. However, there may be value in supplementing tallow‐based diets with DHA to enhance tissue levels and possibly growth.