The effects of a vegetarian and vegan diet on plasma and erythrocyte lipids

Vegetarians usually consume milk, cheese and eggs, whilst vegans consume a diet consisting entirely of plant foods. The protein in a vegan diet is therefore entirely of plant origin. The vegan diet also differs from that of vegetarians and omnivores in having a lower fat content, no cholesterol and a high proportion of short-chain polyunsaturated fatty acids, particularly linoleic acid. The diet of large numbers of people in the Third World is predominantly of plant origin and vegans are an excellent natural ‘experimental model’ for the study of the effects of such a diet on plasma and membrane lipids. The serum cholesterol and triglycerides were lower in vegans, but not in vegetarians, than in age-sex-matched omnivores. Vegan plasma phosphoglycerides contained a lower proportion of 16∶0 and 18∶1 fatty acids, but a higher proportion of 18∶2ω6. The proportion of the longer chain polyunsaturated fatty acids of the ω6 series tended to be higher and the differences were significant for 20∶2ω6, 20∶4ω6 and 22∶4ω6. The proportion of the fatty acids of the ω3 series were lower. Similar differences were found in the erythrocytes. The concentrations in vegetarians were intermediate between those of vegans and omnivores. It is concluded that a vegan diet may have some benefit in that it results in lower serum concentrations of cholesterol and triglycerides. The importance of the differences in membrane fatty acid. Vegetarians usually consume milk, cheese and eggs, whilst vegans, for a variety of reasons, consume a diet consisting only of unrefined cereal, legumes, nuts and vegetable and fruit products. The protein in a vegan diet is therefore solely of plant origin. The diet of vegans differs, however, from that of vegetarians and omnivores in respect of its lipid content, for not only is the total amount of lipid lower, but it contains no cholesterol or long chain polyunsaturated fatty acids, that is fatty acids with a carbon chain length of twenty carbon atoms or more. On the other hand, it contains a high proportion of short chain polyunsaturated fatty acids, notably linoleic and linolenic acids. The health of vegetarians and vegans appears to differ little from that of omnivores (Hardinge & Stare, 1954; Ellis & Montegriffo, 1970; Ellis, West & Sanders, 1977). Indeed, a vegan diet might be though to offer some advantage in relation to arteriosclerosis because animal tat has been implicated in its aetiology (Royal College of Physicians, 1976). In support of this suggestion, epidemiological evidence shows that the incidence of ischaemic heart disease is lower in countries where the typical diet contains a low proportion of animal products. However, in experimental animals changes in the fatty acid composition of the diet result in changes in the fatty acids of cell membranes which are associated with changes in the behaviour and function of the membranes (Holman, 1970a,b). In man information about these effects is not easily obtained and seemea to be important in view of the fact that the diet of large numbers of people in the Third World is predominantly of plant origin. Vegans seemed to offer an excellent natural ‘experimental model’ for the study of these effects. We decided also to study individuals on a vegetarian diet which is intermediate between that of vegans and omnivores and also because in this country vegetarians are much more common than vegans and the number of people adopting this diet seems to be increasing.     

Fatty acids of maize pollen – Quantification,nutritional and morphological evaluation

The aim of this work was to identify and quantify fatty acids presented in pollen samples collected from six different Serbian maize hybrids by GC capillary method. Due to great importance of fatty acids as food component potential nutritional value of maize pollen as food supplement in human diet was determined. It has been shown that pollen is a great source of different fatty acids, especially unsaturated fatty acids. In total, twenty eight fatty acids were quantify - the most abundant saturated FAs were palmitic and henicosanoic acid; the most prevalent monounsaturated FAs were oleic, elaidic and cis-10-heptadecenoic acid. Linoleic and cis-11,14-eicosadienoic acid were the most abundant polyunsaturated fatty acid. Also, it was found that FAs composition was significantly influenced by the type of maize hybrids. According to nutritional recommendations, four of six pollen samples had good nutritional quality with unsaturated/saturated fatty acids ratio higher than 1.6, but there is unsatisfied distribution of ω-6 and ω-3 fatty acids as the most important type of unsaturated fatty acids.     

Does Consumption of Baker’s Yeast (Saccharomyces cerevisiae) by Black Soldier Fly (Diptera: Stratiomyidae) Larvae Affect Their Fatty Acid Composition?

Fatty acids are important compounds for insects, but the requirements for essential fatty acids may differ between insect species. Most of the fatty acids are acquired through the insect’s diet; therefore, supplementing the diet with baker’s yeast (Saccharomyces cerevisiae Meyen ex E.C. Hansen), which produces unsaturated fatty acids, was predicted to affect the fatty acid composition of the insect. The tested insect was the black soldier fly (BSF) (Hermetia illucens L.), that is used as a source of protein and fat in feed. Therefore, there is importance for BSF larvae (BSFL) nutritional composition, especially the unsaturated fatty acids content, which is one of the nutritional limitations for mammalian diets. The dominant fatty acids of the tested BSFL were the saturated fatty acids: lauric, myristic, and palmitic acids, as found in other BSF studies. Oleic acid (c18:1) and linoleic acid (C18:2) were the abundant unsaturated fatty acids in the BSFL. The proportion of linoleic acid was higher in the substrate with the supplemental yeast; however, this did not affect its proportion in the larvae. The higher proportion of linoleic acid may have been exploited as a source for production of saturated lauric acid. Therefore, providing unsaturated fatty acids to the substrate through supplemental baker’s yeast is not the most efficient way to increase the proportion of unsaturated fatty acids in the larvae.     

Effects of a tristearate-containing lipid and canola oil on plasma and tissue lipids in rats

Male Sprague-Dawley rats were fed semipurified diets containing 12% fat and 0.4% cholesterol for 4 wk. The fats were palm oil, a high-stearate fat and canola oil; each of the latter two fat sources was substituted for palm oil in 4% (w/w) increments (i.e, 4, 8 and 12%) thus yielding 3 stearate-containing, 3 canola-containing, and a 12% palm oil diet. Stearate-fed animals exhibited significantly decreased food efficiency ratios, plasma total cholesterol, and liver cholesterol whereas the substitution of canola for palm oil did not consistently alter these parameters. Liver fatty acids generally reflected the composition of the dietary fat sources with the exception of significantly higher arachidonate observed in the stearate-fed rats.     

Effects of a Fish Oil Rich in Docosahexaenoic Acid on Cardiometabolic Risk Factors and Oxidative Stress in Healthy Rats

Omega-3 polyunsaturated fatty acids are associated with a lower risk of cardiometabolic diseases. However, docosahexaenoic acid (DHA) is easily oxidized, leading to cellular damage. The present study examined the effects of an increased concentration of DHA in fish oil (80% of total fatty acids) on cardiometabolic risk factors and oxidative stress compared to coconut oil, soybean oil, and fish oil containing eicosapentaenoic acid (EPA) and DHA in a balanced ratio. Forty healthy male Sprague–Dawley rats were supplemented with corresponding oil for 10 weeks. Supplementation with the fish oil containing 80% DHA decreased plasma fat, plasma total cholesterol and muscle fat compared to the coconut oil and the soybean oil. Increasing concentrations of DHA induced incorporation of DHA and EPA in cell membranes and tissues along with a decrease in ω-6 arachidonic acid. The increase in DHA promoted lipid peroxidation, protein carbonylation and antioxidant response. Taken together, the increased concentration of DHA in fish oil reduced fat accumulation compared to the coconut oil and the soybean oil. This benefit was accompanied by high lipid peroxidation and subsequent protein carbonylation in plasma and in liver. In our healthy framework, the slightly higher carbonylation found after receiving fish oil containing 80% DHA might be a protecting mechanism, which fit with the general improvement of antioxidant defense observed in those rats.     

Influence of palm oil ( Elaesis guineensis) on health

In recent times there has been a growing research interest in palm oil, one of the major edible plant oils in the tropical countries, because of the link between dietary fats and coronary heart disease. Obtained from a tropical plant, Elaesis guineensis, it has a polyunsaturated fatty acid/saturated fatty acid ratio close to unity and a high amount of antioxidant vitamin A precursors and vitamin E. Palm oil is consumed in the fresh state and/or at various levels of oxidation. Feeding experiments in various animal species and humans have highlighted the beneficial role of fresh palm oil to health. These benefits include reduction in the risk of arterial thrombosis and atherosclerosis, inhibition of cholesterol biosynthesis and platelet aggregation, and reduction in blood pressure. However, a considerable amount of the commonly used palm oil is in the oxidized state which possesses potential dangers to the physiological and biochemical functions of the body. Oxidation is as a result of processing the oil for various culinary purposes. Studies have revealed that relative to fresh palm oil, oxidized palm oil induces an adverse plasma lipid profile, free fatty acids, phospholipids and cerebrosides. Additionally, oxidized palm oil induces reproductive toxicity and organotoxicity particularly of the kidneys, lungs, liver and heart. Available evidence suggests that at least part of the oxidized oil impact on health reflects generation of toxicants due to oxidation. The reduction of the dietary level of oxidized oil and/or the level of oxidation may reduce the health risk associated with consumption of oxidized fats.     

Serum and liver lipids in rats fed diets containing corn oil,cottonseed oil,or a mixture of corn and cottonseed oils

Previous research has demonstrated that the total replacement of corn oil (CO) with cottonseed oil (CSO) in the diets of growing male rats results in a lowering of the total cholesterol (TC) concentration in the serum. It is not, however, known if a partial replacement of dietary CO with CSO would be sufficient to lower TC levels, nor is the effect of replacing dietary CO with CSO on other indices of cholesterol status (e.g., the levels of high-density lipoprotein cholesterol [HDL-C], non-HDL-C [i.e., very-low and low-density lipoprotein-cholesterol], or the TC/HDL-C ratio). Growing male rats were fed diets having CO, CSO, or a CO/CSO (1:1, w/w) oil mixture (OM) as the source of dietary oil (diet groups CO, CSO, and OM, respectively). There were no differences between CO and OM groups for TC, HDL-C, non-HDL-C, or the TC/HDL-C ratio. However, TC was significantly lower (p 0.05)for the CSO group than the CO group (2.85 vs. 3.23 mmol/l, or 110 vs. 125 mg/dl, respectively) as was HDL-C (1.83 vs. 2.13 mmol/l, or 71 vs. 82 mg/dl, respectively), but there were no differences between these groups for non-HDL-C or the TC/HDL-C ratio. Diet had no effect on serum triglycerides (TGs) or on total liver content of either cholesterol or TGs. Thus, partial (50%) replacement of CO with CSO was without effect on any of these serum indices of cholesterol status, but total replacement resulted in lower TC and HDL-C, without affecting non-HDL-C or the TC/HDL-C ratio. Because, relative to CO, CSO has higher levels of saturated fatty acids but lower levels of monounsaturated and polyunsaturated fatty acids, the cholesterol-lowering effect of CSO appears to be unrelated to its fatty acid composition, and may be caused by a component of its nonsaponifiable fraction.     

豫南茶树种质资源籽实脂肪含量及脂肪酸组成分析

以豫南地区42份茶树种质资源的茶籽为研究对象,分析了茶籽含仁率及茶籽仁的脂肪含量,范围分别在33.53%~71.60%、17.77%~38.39%。利用气-质联用技术（GC-MS）检测了茶籽仁中的脂肪酸组成和含量,共检测到21种脂肪酸,其中主要成分棕榈酸、硬脂酸、顺-油酸、亚油酸和α-亚麻酸的含量分别在2.64%~5.70%、0.21%~1.11%、7.33%~17.29%、0.09%~8.44%和0.01%~0.15%;相关性分析显示,顺-油酸与十三碳酸、十四碳酸和顺-二十碳二烯酸的含量呈极显著负相关,亚油酸与反-油酸、顺-二十二碳六烯酸含量呈极显著负相关;除了水仙7202茶籽仁中的饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量比值为3.08∶12.16∶1,其余茶树种质资源茶籽仁中,这三类脂肪酸的比值均约为1∶2.69∶1.37。中黄1号、农抗早、迎霜、鄂茶11号、龙井43、中选8号、崂山3号和黄金叶8个茶树品种,不仅含仁率和脂肪含量较高,而且茶籽仁脂肪酸的组分和含量丰富、均衡,可初步筛选出来作为豫南地区叶籽两用茶园的候选品种。     

Long-Term Feeding of Chitosan Ameliorates Glucose and Lipid Metabolism in a High-Fructose-Diet-Impaired Rat Model of Glucose Tolerance

This study was designed to investigate the effects of long-term feeding of chitosan on plasma glucose and lipids in rats fed a high-fructose (HF) diet (63.1%). Male Sprague-Dawley rats aged seven weeks were used as experimental animals. Rats were divided into three groups: (1) normal group (normal); (2) HF group; (3) chitosan + HF group (HF + C). The rats were fed the experimental diets and drinking water ad libitum for 21 weeks. The results showed that chitosan (average molecular weight was about 3.8 × 10⁵ Dalton and degree of deacetylation was about 89.8%) significantly decreased body weight, paraepididymal fat mass, and retroperitoneal fat mass weight, but elevated the lipolysis rate in retroperitoneal fats of HF diet-fed rats. Supplementation of chitosan causes a decrease in plasma insulin, tumor necrosis factor (TNF)-α, Interleukin (IL)-6, and leptin, and an increase in plasma adiponectin. The HF diet increased hepatic lipids. However, intake of chitosan reduced the accumulation of hepatic lipids, including total cholesterol (TC) and triglyceride (TG) contents. In addition, chitosan elevated the excretion of fecal lipids in HF diet-fed rats. Furthermore, chitosan significantly decreased plasma TC, low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C), the TC/high-density lipoprotein cholesterol (HDL-C) ratio, and increased the HDL-C/(LDL-C + VLDL-C) ratio, but elevated the plasma TG and free fatty acids concentrations in HF diet-fed rats. Plasma angiopoietin-like 4 (ANGPTL4) protein expression was not affected by the HF diet, but it was significantly increased in chitosan-supplemented, HF-diet-fed rats. The high-fructose diet induced an increase in plasma glucose and impaired glucose tolerance, but chitosan supplementation decreased plasma glucose and improved impairment of glucose tolerance and insulin tolerance. Taken together, these results indicate that supplementation with chitosan can improve the impairment of glucose and lipid metabolism in a HF-diet-fed rat model.     

Fatty Acid Composition of Serum,Adipose Tissue,and Liver in Rats Fed Diets Containing Corn Oil or Cottonseed Oil

There have been few studies on the effect of cottonseed oil (CSO), one of the most commonly used vegetable oils in the United States, on indices of lipid status either in the rat or in any other species. Previous studies with rats have focused on the effect of CSO, versus that of other vegetable oils, on the concentration of cholesterol in serum and liver or on a limited number of fatty acids in serum, adipose tissue, or liver. The present study was designed to compare more fully than in previous studies the effect of CSO to that of corn oil (CO) on the fatty acid composition of serum, adipose tissue, and liver. Two groups of male rats (n=10 each) were used, each fed one of two purified diets containing 100 g/kg of either CO or CSO. Between-group differences included higher values (mol% total fatty acids) in adipose tissue for palmitic acid and stearic acid, but lower values in serum, adipose tissue, and liver for cis-vaccenic acid and oleic acid (C18:1n-9) for the CSO group than the CO. In addition, values in serum, adipose tissue, and liver for -linolenic acid (C18:3n-3) and its metabolite, docosahexaenoic acid (C22:6n-3), were lower for the CSO group than the CO. There was no effect of diet on serum or tissue levels of n-6 fatty acids (linoleic acid, dihomo--linolenic acid, and arachidonic acid). Differences in fatty acid compositions noted, e.g., those for C18:1n-9 and C22:6n-3, mainly reflected compositional differences between the two oils. Thus, use of CSO rather than CO affected serum and tissue concentrations of saturated, monounsaturated, and n-3 polyunsaturated fatty acids (PUFAs) but had no effect on n-6 PUFA status.     

Plant Extracts of Winter Savory, Purple Coneflower, Buckwheat and Black Elder Activate PPAR-γ in COS-1 Cells but do not Lower Blood Glucose in Db/db Mice In vivo

The aim of this study was to investigate possible blood glucose-lowering effects of plant extracts in vivo for which prior to this a peroxisome proliferator-activated receptor-γ activity in vitro was observed. The ability of extracts of winter savory, purple coneflower, buckwheat and black elder to dose-dependently activate peroxisome proliferator-activated receptor-γ was determined in a reporter gene assay in COS-1 cells. For evaluation of glucose-lowering effects in vivo, db/db mice were fed a diet containing either rosiglitazone (0.02 g/kg diet, positive control) or one of the plant extracts (0.1 and 1 g/kg diet) for four weeks. Apart from glucose, insulin, triacylglycerols, non-esterified fatty acids, cholesterol and adiponectin were determined in plasma. All plant extracts showed a dose-dependent peroxisome proliferator-activated receptor-γ-activating effect in vitro. In db/db mice none of the plant extracts exerted glucose-lowering effects at the used dosages compared to rosiglitazone. Non-esterified fatty acids, triacylglycerols, cholesterol, insulin and adiponectin in plasma were not altered by the plant extracts as well. Although dose-dependent peroxisome proliferator-activated receptor-γ activity could be shown in COS-1 cells, the experiments in db/db mice lacked to confirm any anti-diabetic effect of the plant extracts in vivo and emphasizes the importance of verifying cell culture data using an appropriate in vivo model.     

低热量功能性油脂——结构脂质的研究与开发前景

从功能性油脂分类的角度,对多不饱和脂肪酸、磷脂和新型功能性油脂——结构脂质的发展史及国内外研究概况进行了介绍,并对现阶段广泛研究的新型功能性油脂——结构脂质的合成方法做了介绍。揭示了以大豆为原料,通过酶法催化工艺,开发一种新型低热量功能性油脂对于改善人民健康水平的重要意义。     

Effects of Feeding Potato Pulp on Cholesterol Metabolism and Its Association with Cecal Conditions in Rats

To clarify the functional properties of potato pulp (PP), a waste product resulting from extraction of starch from potatoes, we examined the effects of PP on cholesterol metabolism and cecal conditions in rats. Plasma total cholesterol (T-Chol) levels were lower in rats fed a PP-supplemented diet for four weeks than in those fed a control diet. Cecal pH was lowered due to an increase in the levels of cecal total short-chain fatty acids, especially butyrate, in the PP group compared to the control group. Furthermore, animals fed with the PP-supplemented diet showed increased cecal ratios of Lactobacillus and Clostridia and decreased cecal ratios of Bacteroides and Gammaproteobacteria with slightly negative and positive correlations with plasma T-Chol levels, respectively. In conclusion, ingestion of PP for four weeks is likely to improve both cecal conditions and cholesterol metabolism, suggesting that PP has prebiotic effects.     

Lipid profile of rats fed blends of rice bran oil in combination with sunflower and safflower oil

This study was undertaken to assess the effect of blended oils, i.e., polyunsaturated fatty acid (PUFA) rich vegetable oils like safflower oil (SFO) and sunflower oil (SNO) with the unconventional and hypocholesterolemic rice bran oil (RBO) on the serum lipid profile of rats. Rats fed RBO + SNO/SFO at 70:30 ratio for a period of 28 days showed significantly (p < 0.05) lower levels of total cholesterol (TC), triglycerides (TG) and low density lipoprotein (LDL) cholesterol and increased high density lipoprotein (HDL) cholesterol in animals fed a high cholesterol diet (HCD) and cholesterol free diet (CFD). Liver total cholesterol (TC) and triglycerides (TG) were also reduced. Fecal excretion of neutral sterols and bile acids was increased with use of RBO blends. RBO, which is rich in tocopherols and tocotrienols, may improve the oxidative stability of the blends. Tocotrienols are known to inhibit 3-hydroxy, 3-methyl, glutaryl CoA (HMG-COA) reductase (rate limiting enzyme in cholesterol biosynthesis), resulting in hypocholesterolemia. In addition to improving the lipid profile by lowering TC, TG and LDL-C and increasing HDL-C, blending of RBO with other oils can result in an economic advantage of lower prices.     

Florisil固相萃取法联用气相色谱测定油脂中sn-2位脂肪酸

为探寻与气相色谱分析相配套的高效前处理方法,以测定不同物种来源的油脂中sn-2位(β位)脂肪酸组成及含量,考察了Florisil固相萃取柱对经sn-1,3专一性脂肪酶水解后的油脂各产物的分离富集能力,并对萃取条件进行了优化。结果表明,Florisil固相萃取柱能有效地将sn-2单甘脂从油脂水解产物中分离;同时发现Florisil固相萃取可以实现油脂水解产物中甘油三酯、甘油二酯、单甘脂及游离脂肪酸的依次分离。5种不同来源的油脂(植物油、藻油、微生物油脂、鱼油和海豹油脂),水解后经Florisil固相萃取柱萃取,联用气相色谱测定sn-2位脂肪酸组成及含量,结果表明,植物油、藻油和海豹油中sn-2位主要为中长链不饱和脂肪酸(植物油sn-2位中C18∶1,C18∶2和C18∶3约占95%;藻油sn-2位中C16∶1,C18∶1和C18∶2约占50%;海豹油sn-2位中C16∶1,C18∶1和C18∶2约占67%),菌油和鱼油中sn-2位多为长链多不饱和脂肪酸(菌油sn-2位中C20∶4约占37%;鱼油sn-2位中C20∶5,C22∶5和C22∶6约占40%)。     

Polyunsaturated Fatty Acids of Marine Macroalgae: Potential for Nutritional and Pharmaceutical Applications

As mammals are unable to synthesize essential polyunsaturated fatty acids (PUFA), these compounds need to be taken in through diet. Nowadays, obtaining essential PUFA in diet is becoming increasingly difficult; therefore this work investigated the suitability of using macroalgae as novel dietary sources of PUFA. Hence, 17 macroalgal species from three different phyla (Chlorophyta, Phaeophyta and Rhodophyta) were analyzed and their fatty acid methyl esters (FAME) profile was assessed. Each phylum presented a characteristic fatty acid signature as evidenced by clustering of PUFA profiles of algae belonging to the same phylum in a Principal Components Analysis. The major PUFA detected in all phyla were C₁₈ and C₂₀, namely linoleic, arachidonic and eicosapentaenoic acids. The obtained data showed that rhodophytes and phaeophytes have higher concentrations of PUFA, particularly from the n-3 series, thereby being a better source of these compounds. Moreover, rhodophytes and phaeophytes presented “healthier” ∑n-6/∑n-3 and PUFA/saturated fatty acid ratios than chlorophytes. Ulva was an exception within the Chlorophyta, as it presented high concentrations of n-3 PUFA, α-linolenic acid in particular. In conclusion, macroalgae can be considered as a potential source for large-scale production of essential PUFA with wide applications in the nutraceutical and pharmacological industries.     

番木瓜,橄榄蜂花粉营养成分的分析与评价

经测定,番木瓜、橄榄蜂花粉的蛋白质含量分别为２１．８３１％和１９．１９４％;总糖含量分别为２２．６６％及２２．０８％冰解氨基酸的总含量分别为２１．７０７％和２３．３０７％,游离氨基酸的总含量分别是３９４．２５７ｍｇ／１００ｇ和５６２．９４１ｍｇ／１００ｇ,两者均具８种人体必需氨基酸,总含量分别为９．１１８％和８．８５１％,比值与ＦＡＯ／ＷＨＯ（１９７３）提出的理想蛋白质中人体必需氨基酸的比率模式接近,氨基酸分分别为７７．７和９２．６,番木瓜的限制性氨基酸为亮氨酸和缬氨酸,橄榄的限制性氨基酸为完氨酸。不饱和脂肪酸占脂肪酸总含量的６８．７９％和６７．７９％,多烯不饱和脂肪酸与饱和脂肪酸的比值分别为１．６９及１．４３。番木瓜、橄榄蜂花粉含１０种维生素,其中维生素Ｃ含量最高,分别达到５０．３２ｍｇ／１００ｇ和３５．４１ｍｇ／１００ｇ;番木瓜、橄榄蜂花粉除磷、钙、锌的含量普遍较高外,多数矿质元素的含量与其他果树蜂花粉相近。     

Palm oil: Biochemical,physiological, nutritional,hematological and toxicological aspects: A review

The link between dietary fats and cardiovascular diseases has necessitateda growing research interest in palm oil, the second largest consumedvegetable oil in the world. Palm oil, obtained from a tropical plant, Elaeis guineensis contains 50% saturated fatty acids, yet it does notpromote atherosclerosis and arterial thrombosis. The saturated fatty acidto unsaturated fatty acid ratio of palm oil is close to unity and it containsa high amount of the antioxidants, -carotene, and vitamin E. Although palm oil-based diets induce a higher blood cholesterol level thando corn, soybean, safflower seed, and sunflower oils, the consumption ofpalm oil causes the endogenous cholesterol level to drop. Thisphenomenon seems to arise from the presence of the tocotrienols and thepeculiar isomeric position of its fatty acids.The benefits of palm oil to health include reduction in risk of arterialthrombosis and atherosclerosis, inhibition of endogenous cholesterolbiosynthesis, platelet aggregation, and reduction in blood pressure. Palm oilhas been used in the fresh state and/or at various levels of oxidation.Oxidation is a result of processing the oil for various culinary purposes.However, a considerable amount of the commonly used palm oil is in theoxidized state, which poses potential dangers to the biochemical andphysiological functions of the body. Unlike fresh palm oil, oxidized palm oilinduces an adverse lipid profile, reproductive toxicity and toxicity of thekidney, lung, liver, and heart. This may be as a result of the generation oftoxicants brought on by oxidation. In contrast to oxidized palm oil, red orrefined palm oil at moderate levels in the diet of experimental animalspromotes efficient utilization of nutrients, favorable body weight gains,induction of hepatic drug metabolizing enzymes, adequatehemoglobinization of red cells and improvement of immune function. However, high palm oil levels in the diet induce toxicity to the liver asshown by loss of cellular radial architecture and cell size reductions whichare corroborated by alanine transaminase to aspartate transaminase ratioswhich are higher than unity.The consumption of moderate amounts of palm oil and reduction in thelevel of oxidation may reduce the health risk believed to be associated withthe consumption of palm oil. Red palm oil, by virtue of its-carotene content, may protect against vitamin A deficiency andcertain forms of cancer.     

大豆种子脂肪酸组分的研究进展

随着社会的进步和人们生活水平的提高,人们越来越重视自身的健康状况.大豆油的饱和脂肪酸与不饱和脂肪酸的比例相对其它的植物油(如菜籽油、花生油等)较为合理,其消费量和食用量也已经逐步超过了其它植物油,成为人们日常饮食重要的营养来源之一.本文在脂肪酸组成、脂肪酸组分形成与地理纬度、气象因素的关系、及发育种子脂肪酸组分的形成等方面综述了大豆种子脂肪酸组分的研究进展,并指出了该领域目前存在的主要问题和发展的前景.     

Effects of n-3 Polyunsaturated Fatty Acids (ω-3) Supplementation on Some Cardiovascular Risk Factors with a Ketogenic Mediterranean Diet

Background: the ketogenic diet (KD) has become a widely used nutritional approach for weight loss. Some of the KD’s positive effects on metabolism and cardiovascular risk factors are similar to those seen after n-3 polyunsaturated fatty acids (ω-3) supplementation. We hypothesized that a ketogenic Mediterranean diet with phytoextracts combined with ω-3 supplementation may have increased positive effects on cardiovascular risk factors and inflammation. Methods: We analyzed 34 male overweight subjects; aged between 25 and 65 years who were overall healthy apart from overweight. The subjects followed a ketogenic diet protocol for four weeks; with (KDO3) or without (KD) ω-3 supplementation. Results: All subjects experienced a significant loss of body weight and body fat and there was no significant differences between treatment (body weight: KD—4.7 kg, KDO3—4.03 kg, body fat KD—5.41 kg, KDO3—5.86 kg). There were also significant decreases in total cholesterol, LDL-c, and glucose levels. Triglycerides and insulin levels decreased more in KDO3 vs. KD subjects, with a significant difference. All the investigated inflammatory cytokines (IL-1β, IL-6, TNF-α) decreased significantly in KDO3 subjects whilst only TNF-α showed a significant decrease in KD subjects over the 12 month study period. No significant changes were observed in anti-inflammatory cytokines (IL-10 and IL-1Ra), creatinine, urea and uric acid. Adiponectin increased significantly only in the KDO3 group. Conclusions: ω-3 supplementation improved the positive effects of a ketogenic Mediterranean diet with phytoextracts on some cardiovascular/metabolic risk factors and inflammatory state.