南极磷虾油、鱼油与花生四烯酸油对骨质疏松症小鼠脂质代谢的影响

目的：比较南极磷虾油、鱼油和花生四烯酸油对去卵巢骨质疏松小鼠脂质代谢的影响。方法：对8 周龄健康雌性C57BL/6J小鼠部分进行双侧去卵巢手术,建立绝经后骨质疏松症模型;部分不进行去卵巢手术,仅进行开腹腔与缝合的假手术,作为假手术组（生理盐水）。将造模成功的小鼠分为模型对照组（生理盐水）、南极磷虾油组（150 mg/kg mb）、鱼油组（80 mg/kg mb）和花生四烯酸油组（140 mg/kg mb）。连续灌胃12 周后取材,测定骨密度,血清和肝脏中的总胆固醇、甘油三酯水平,肝脏中脂质合成相关基因表达水平等相关指标。结果：两种n-3多不饱和脂肪酸（polyunsaturated fatty acids,PUFA）油脂南极磷虾油和鱼油能极显著降低骨质疏松小鼠体脂比（P＜0.01）,改善血脂及肝脏脂质水平,显著或极显著下调肝脏中脂质合成关键基因SREBP-1c、FAS、ACC、SCD1的mRNA表达（P＜0.05、P＜0.01）;而n-6 PUFA油脂花生四烯酸油会升高血脂水平并上调肝脏中脂质合成关键基因的表达。结论：两种n-3 PUFA均能够显著改善骨质疏松小鼠脂代谢紊乱,且南极磷虾油效果更好;而n-6 PUFA花生四烯酸油则加剧脂代谢紊乱。     

响应面法优化脂肪酶富集金枪鱼油中二十二碳六烯酸甘油酯工艺研究

以金枪鱼副产物为原料提取精炼鱼油,研究了皱褶假丝酵母脂肪酶（Candida Rugosa）富集金枪鱼油二十二碳六烯酸（ Docosahexaenoic Acid, DHA）甘油酯的工艺条件。在单因素实验的基础上选取水油质量比、脂肪酶添加量、反应温度和时间4个因素为自变量,以甘油酯中DHA、ω-3含量和甘油酯得率为响应值,采用中心组合（box–behnken）进行响应面实验设计和分析。结果表明,最佳条件为水油比1:1.7,脂肪酶添加量1%,反应温度50 ℃,反应时间3 h。在此条件下,甘油酯中DHA质量分数为35.55%,ω-3质量分数为42.25%,甘油酯得率为73.85%。本课题成功建立了甘油酯中DHA 、ω-3含量 (R2 = 0.8832) 和甘油酯得率(R2 = 0.9425) 的拟合模型。卡方检验分析表明这两种模型的预测值和实测值无显著性差异(P > 0.05)。     

Mechanisms of Docosahexaenoic and Eicosapentaenoic Acid Loss from Pacific Saury and Comparison of Their Retention Rates after Various Cooking Methods

The docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents of Pacific saury (Cololabis saira), a fatty fish and staple of the Japanese diet, have been reported to decrease after cooking. This study compared the DHA and EPA contents remaining in saury after grilling, pan‐frying or deep‐frying to center temperatures of 75, 85, or 95 °C, and examined physical loss, lipid oxidation, and thermal degradation as mechanisms of DHA and EPA loss. Temperature changes inside the saury were monitored using thermocouples, while DHA and EPA contents, oxygen radical absorbance capacity, and measurements of lipid oxidation (that is, carbonyl value and thiobarbituric acid value) were determined chemically. Visualization of temperature distribution inside fish samples during cooking revealed large differences in heat transfer among cooking methods. True retention rates in grilled (DHA: 84 ± 15%; EPA: 87 ± 14%) and pan‐fried samples (DHA: 85 ± 16%; EPA: 77 ± 17%) were significantly higher than deep‐fried samples (DHA: 58 ± 17%; EPA: 51 ± 18%), but were not affected by final center temperatures despite differences in cooking times. Physical loss via cooking losses (grilling and pan‐frying) or migration into frying oil (deep‐frying) accounted for large quantities of DHA and EPA loss, while lipid oxidation and thermal degradation did not appear to be major mechanisms of loss. The antioxidant capacity of saury was not significantly affected by cooking treatments. The results of this study suggest that minimization of physical losses during cooking may increase DHA and EPA contents retained in cooked Pacific saury.     

Fish Oil Dietary Effects on Fatty Acid Composition and Flavor of Channel Catfish

A typical channel catfish diet was supplemented with 0, 1.5, and 3% menhaden oil. Fillets were subjected to lipid, fatty acid, and TBA analyses. After 6 mo storage at ?18°C, fillets were again analyzed for TBA value and flavor panel profile. Fillets from catfish fed diets with 1.5 and 3% supplemental fish oil had elevated levels of n-3 fatty acids (P<0.05). TBA number and off-flavor attributes were not affected by treatments. Menhaden oil supplementation up to 3% enhanced the content of n-3 fatty acids in channel catfish fillets without adversely affecting flavor attributes or storage quality.     

鱼油DHA脂质体的制备及稳定性

以鱼油二十二碳六烯酸（docosahexaenoic acid,DHA）为原料,分别采用薄膜分散法和薄膜分散法联合动态高压微射流技术（dynamic high pressure microfluidization,DHPM）制备鱼油DHA粗脂质体（crude liposomes-DHA,CLs-DHA）和纳米脂质体（nanoliposomes-DHA,NLs-DHA）。以平均粒径、多分散指数（polydispersity index,PDI）和Zeta电位为评价指标,考察CLs-DHA和NLs-DHA的pH值稳定性和贮藏稳定性。结果表明：随着pH值逐渐增大,CLs-DHA和NLs-DHA的平均粒径和PDI均呈下降趋势,Zeta电位绝对值逐渐升高,在pH 7.4时具有较好的稳定性,NLs-DHA变化相对小于CLs-DHA;在4 ℃贮藏95 d过程中,与NLs-DHA相比,CLs-DHA的平均粒径、PDI和Zeta电位变化幅度相对较大,可见NLs-DHA的稳定性优于CLs-DHA;差示扫描量热法分析结果也表明,适度的DHPM处理可增强脂质体的稳定性,NLs-DHA具有更好的稳定性。     

Dietary Supplementation with Fish Oil or Conjugated Linoleic Acid Relieves Depression Markers in Mice by Modulation of the Nrf2 Pathway

Inflammation and oxidative stress play an important role in the pathogenesis of depressive disorders and nuclear erythroid related factor 2 (Nrf2), a regulator of RedOx homeostasis and inflammation, is a promising target for depression prevention/treatment. As fish oil (FO) and conjugated linoleic acid (CLA) are known Nrf2 inducers, their protective ability is comparatively evaluated in a murine model of depression (MRL/MpJ‐Fas^lpr). Oxidative stress, fatty acids content, and critical factors reflecting brain functioning—namely brain‐derived neurotrophic factor (BDNF), synaptic markers, and cholinergic signaling—are preliminarily evaluated in the frontal cortex of 8‐week (Young) and in 22‐week old animals (Old), which are used as model of depression. These markers are measured in Old mice at the end of a 5‐week pretreatment with FO or CLA (728 or 650 mg kg^–1, respectively). Old mice exhibit disrupted Redox homeostasis, compensatory Nrf2 hyperactivation, lower docosaheaxaenoic acid (DHA), and lower BDNF and synaptic function proteins compared to Young mice. FO and CLA treatment relieves almost all the pathophysiological hallmarks at a level comparable to Young mice. Presented data provide the first evidence for the comparable efficacy of FO or CLA supplementation in preventing depression signs in Old MRL/lpr mice, likely through their ability of improving Nrf2‐mediated antioxidant defenses.     

Omega‐3 Fatty Acid Profile of Eggs from Laying Hens Fed Diets Supplemented with Chia,Fish Oil,and Flaxseed

The aim of this study was to investigate the effect of diets supplemented with fish oil, flaxseed, and chia seed on the omega‐3 fatty acid composition and sensory properties of hens’ eggs. No significant difference in yolk fat content was found between treatments. The fatty acid composition of egg yolk was significantly affected by the dietary treatments. Inclusion of chia at 300 g/kg into the diet produced eggs with the highest concentration of omega‐3 fatty acid. Eicosapentaenoic acid and docosahexaenoic acid were only detected in eggs from laying hens fed the diet supplemented with fish oil. Diet had a significant effect on color, flavor and overall acceptability of eggs. Types and levels of omega‐3 fatty acids in feed influence the level of yolk omega‐3 fatty acids in egg yolk. Inclusion of chia into the hens’ diet significantly increased the concentration of yolk omega‐3 fatty acid without significant change in sensory properties.     

Dietary Mannan Oligosaccharides Modulate Gut Microbiota,Increase Fecal Bile Acid Excretion,and Decrease Plasma Cholesterol and Atherosclerosis Development

1 Scope

Mannan oligosaccharides (MOS) have proven effective at improving growth performance, while also reducing hyperlipidemia and inflammation. As atherosclerosis is accelerated both by hyperlipidemia and inflammation, we aim to determine the effect of dietary MOS on atherosclerosis development in hyperlipidemic ApoE*3‐Leiden.CETP (E3L.CETP) mice, a well‐established model for human‐like lipoprotein metabolism.

2 Methods and results

Female E3L.CETP mice were fed a high‐cholesterol diet, with or without 1% MOS for 14 weeks. MOS substantially decreased atherosclerotic lesions up to 54%, as assessed in the valve area of the aortic root. In blood, IL‐1RA, monocyte subtypes, lipids, and bile acids (BAs) were not affected by MOS. Gut microbiota composition was determined using 16S rRNA gene sequencing and MOS increased the abundance of cecal Bacteroides ovatus. MOS did not affect fecal excretion of cholesterol, but increased fecal BAs as well as butyrate in cecum as determined by gas chromatography mass spectrometry.

3 Conclusion

MOS decreased the onset of atherosclerosis development via lowering of plasma cholesterol levels. These effects were accompanied by increased cecal butyrate and fecal excretion of BAs, presumably mediated via interactions of MOS with the gut microbiota.     

鱼油中二十碳五烯酸、二十一碳六烯酸混合乙酯提取方法的研究

本文用尿素沉淀法和分子蒸馏法研究了二十碳五烯酸（ＥＰＡ）、二十二碳六烯酸（ＤＨＡ）乙酯的分离提纯．实验表明,尿素沉淀法能够将ＥＰＡ、ＤＨＡ乙酯提纯到９０％,分子蒸馏法能提纯到７０％以上。但分子蒸馏法提纯工序简单,效率高,尿素沉淀法工序繁杂,效率低．     

鱼油软胶囊中脂肪酸组成及比率分析

采用气相色谱法对海洋鱼油软胶囊中脂肪酸组成和比率进行分析,为合理补充DHA、EPA等多不饱和脂肪酸提供理论依据,并为鉴别海洋鱼油质量提供基础数据。结果表明:鱼油软胶囊中主要含有C14~C22脂肪酸,其中不饱和脂肪酸质量分数50.8%~85.1%,特别是具有重要生理作用的多不饱和脂肪酸,如C20:5(EPA,约占10.0%~35.1%)、C22:6(DHA,约占10.7%~20.5%);鱼油软胶囊中n-3不饱和脂肪酸质量分数约为22.5%~55.7%,n-6不饱和脂肪酸与n-3不饱和脂肪酸的比率约为0~0.7,EPA与DHA的比率约为0.8~1.9。     

鱼粉加工副产物中鱼油的精炼及其脂肪酸组成分析

对鱼粉加工副产物中鱼油的精制进行研究,得到鱼粉加工副产物中鱼油精炼的最佳工艺：添加1%磷酸（体积分数60%）脱胶,3% NaOH（质量分数12%）溶液脱酸以及15%活性炭脱色,在85 ℃条件下减压蒸馏脱臭10 min。在精炼过程中,鱼油中饱和脂肪酸含量下降,其他脂肪酸含量变化较小。所制备鱼油的理化指标均达到精制鱼油一级要求,其中多不饱和脂肪酸总含量达到0.69 g/mL,二十二碳六烯酸和二十碳五烯酸含量分别为0.229 g/mL和0.121 g/mL。     

酶法提取罗非鱼内脏鱼油及脂肪酸组成分析

对酶法提取罗非鱼内脏鱼油的工艺条件进行研究,并对提取鱼油的基本理化性质和脂肪酸组成进行分析。考察了酶种类、酶解温度、p H、液料比、加酶量和酶解时间对罗非鱼内脏鱼油提取率的影响,通过单因素试验和响应面法优化得到酶法提取罗非鱼内脏鱼油的最佳工艺条件为:酶解温度50℃、p H 7.5、液料比5∶1、加酶量3 400 U/g、酶解时间1 h。在此条件下,鱼油提取率达到88.95%,酸价达到SC/T 3502—2000的粗鱼油一级标准。罗非鱼内脏鱼油中饱和脂肪酸相对质量分数为36.66%,单不饱和脂肪酸和多不饱和脂肪酸分别占总脂肪酸质量的38.13%和25.18%,表明罗非鱼内脏鱼油是一种营养品质较高的油脂。     

Effect of different sources of dietary omega‐3 fatty acids on general performance and fatty acid profiles of thigh,breast, liver and portal blood of broilers

One hundred and sixty‐eight 1‐day‐old Cobb broiler chickens were randomly assigned to 12 broiler cages to determine the dietary effect of different sources of oils rich in long‐chain omega‐3 polyunsaturated fatty acids (LCω3PUFA). The following oils were added to the feed at a concentration of 12.5 g kg^?1: a highly refined seal blubber oil (SBO) containing 225 g kg^?1 LCω3PUFA; a fish oil (FO) concentrate containing >800 g kg^?1 LCω3PUFA in the form of triglycerides; and an FO concentrate containing >600 g kg^?1 LCω3PUFA in the form of ethyl esters. Fatty acid profiles of the breast and thigh meat were measured in order to determine the deposition of LCω3PUFA into the body tissues, whilst fatty acid profiles of the liver and the portal blood were taken in order to deduce consequences of the different ester forms on the absorption process. A triangular sensory evaluation was performed on the breast meat. The levels of LCω3PUFA in all tissues and the portal blood reflected the concentrations of LCω3PUFA in the diets. The sensory properties of the breast meat were negatively influenced by ethyl ester supplementation only. Copyright © 2004 Society of Chemical Industry     

Effect of Dietary Partial Hydrolysate of Phospholipids,Rich in Docosahexaenoic Acid‐Bound Lysophospholipids,on Lipid and Fatty Acid Composition in Rat Serum and Liver

Lysophospholipids have been recognized as potent biologically active lipid mediators. However, attention has not been paid to the health benefits of dietary partial hydrolysate of phospholipids (PH‐PL), which is rich in docosahexaenoic acid (DHA)‐bound lysophospholipids. In this study, the effects of PH‐PL on serum and liver lipid profiles of rats upon administration of PH‐PL are demonstrated in comparison to those of fish oil (FO), which comprises eicosapentaenoic acid (EPA) and DHA‐bound triglyceride (TG). PH‐PL containing EPA and DHA was prepared via enzymatic modification of squid (Todarodes pacificus) meal that is rich in phospholipids. Male Wistar rats were fed a basal diet containing soybean oil alone (7%), FO, and PH‐PL. The FO and PH‐PL diets had similar EPA and DHA contents. After the rats had been fed their respective diets for 28 d, their serum and liver lipid contents, fecal lipid excretion, and hepatic gene expression level were measured. The results demonstrated that compared with the soybean oil diet alone, the PH‐PL diet decreased serum and liver TG contents partially because of the enhancement of liver acyl‐CoA oxidase activity and suppression of liver fatty acid synthase activity. In addition, compared with the soybean oil diet, the PH‐PL group exhibited lower serum cholesterol content at least in part because of the reduction of hepatic 3‐hydroxy‐3‐methylglutaryl‐CoA reductase mRNA expression level. We found that dietary administration of EPA and DHA containing PH‐PL has a hypolipidemic effect that may help prevent the development lifestyle‐related diseases.     

不同种类高膳食油脂对小鼠血脂、肝脂及尿酸的影响

为了探讨猪油、植物油及其调和油对血脂、肝脂及血尿酸的影响,评估其对特殊人群的健康潜在风险,本文研究以小鼠为模型,模拟居民用油习惯,将50只8周龄雄性C57BL/6J小鼠随机均分为葵花籽油组(SSO)、豆油组(SO)、猪油组(LO)、葵花籽油与猪油调和油组(SSO-L)、豆油与猪油调和油组(SO-L)5组,模拟我国部分人群(5%~10%)日均烹调油脂高摄入水平(95g/d),每组日粮中分别添加10.5%的不同油脂,饲喂8周后采集血液和肝脏组织,检测血清和肝脏指标。结果显示,相比于其他各组,LO组在体脂和血脂方面都有显著或极显著升高(p0.05,p0.01)。而SSO-L组和SO-L组在肝脂方面显著高于对应的SSO组和SO组(p0.05)。同时,SSO-L组和SO-L组的SUA和肝脏XOD水平都显著高于LO组(p0.05)。表明在95 g/d的膳食油脂摄入水平下,猪油会极大增加肥胖和患脂肪肝病的风险。葵花籽油与猪油调和油和豆油与猪油调和油也会通过升高尿酸水平来增大痛风和脂肪肝的患病风险。此外,长期以该水平摄入这两种调和油对肝脏功能也有明显损伤。在该摄入水平下,豆油为较优选择。     

Analysis of polychlorinated biphenyls (PCBs), heavy metals and omega‐3 fatty acids in commercially available Korean functional fish oil supplements

In this study, the levels of polychlorinated biphenyls (PCBs), heavy metals and omega‐3 polyunsaturated fatty acids (docosahexaenoic acid; DHA and eicosapentaenoic acid; EPA), as well as chemical indices including acid and peroxide values were determined among twenty‐four commercially available functional fish oil supplements. The sum of indicator PCB congeners (congeners 28, 52, 101, 118, 138, 153 and 180) was below the limit of quantification of 0.043 mg kg^?1. Metallic compounds (Cd, Pb, Hg and As) were not detected in all fish oil supplement samples. The relative percentages of EPA and DHA in fish oil supplements ranged from 25% to 80%. The acid values ranged from 0.1 to 1.4 mg KOH per g oil, and peroxide values ranged from 2.7 to 28.8 meq per kg oil. All fish oil supplement samples tested in current study met the safety standard for fish oil supplements set by Korean government as well as International standard.     

Stability,sensory quality,texture properties and nutritional value of fish oil‐enriched spreadable fat

A Correction has been published for this article in Journal of the Science of Food and Agriculture 84(15):2142 (2004). The intake of omega‐3 long‐chain polyunsaturated fatty acids (PUFAs) in the typical Western diet is usually below the recommended level. Without radical changes of eating patterns the diet may be enhanced by enrichment of foods with unhydrogenated fish oil, which is the richest source of the long‐chain omega‐3s, eicosapentaenoicacid (EPA) and docosahexaenoicacid (DHA). The aims of the study were to establish the sensorily acceptable fish oil enrichment level of a reduced‐fat spread, to enhance the omega‐3 long‐chain PUFA content and to evaluate the enriched spread's stability during 3 months of storage (6°C, limited exposure to light and air). Samples were prepared in an industrial pilot plant. Overall sensory quality, intensity of fishy flavour, texture properties (sensory and instrumental), peroxide value, acid number and fatty acids composition were measured. A spread enriched by addition of 30.0 g kg^?1 of unhydrogenated fish oil could be stored for up to 3 months without significant decrease of the measured stability indicators. A daily portion of this enriched spread (30 g) would provide 0.25 g of EPA and DHA, significantly increasing long‐chain omega‐3 levels in the average diet. Copyright © 2004 Society of Chemical Industry