共查询到19条相似文献，搜索用时 531 毫秒
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共轭亚油酸 (CLA)是一系列含有共轭双键的亚油酸的总称 ,包括几何异构体和位置异构体 ,具有独特的生理功能。共轭亚油酸主要存在于反刍动物牛、羊等的乳脂及其肉制品中 ,在一些植物中也发现了共轭亚油酸但含量非常少。一般来说动物产品中所含有的共轭亚油酸较植物油中多 ;反刍动物组织中共轭亚油酸含量较非反刍动物高。1 生物学功能1 1 促进脂肪分解与改善体脂组成 饲喂试验表明 ,CLA能显著降低动物脂肪含量 ,蛋白质含量增加。其机理可能与CLA对动物体内几种与脂质代谢有关的酶活性的影响有关。研究表明 ,CLA可以提高脂肪组织及肌… 相似文献
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共轭亚油酸的生理作用及其在养殖业的应用前景 总被引：8，自引：3，他引：5
共轭亚油酸（CLA）是在双键位置和几何构型上呈异构形式亚油酸的异构体复合物，有１０多种存在形式。CLA是食物中的天然成分，普遍存在于反刍动物性食品如牛奶、奶酪、牛肉、羊肉及脂肪中，脂肪中的CLA含量最高，一般为２．９～８．９２mg／g。自然状态下瘤胃中细菌的亚油酸异构化作用能够产生CLA，因此反刍动物肉及乳品中CLA含量比其它动物高，猪肉及禽肉中的CLA含量相对较少。２０世纪７０年代末，MichaelPariza在烹调过程中寻找肉中诱导有机体突变物质的形成时偶尔发现CLA的存在。Pariza（１９８５）的研究表明，CLA能降低小… 相似文献
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共轭亚油酸及其生物学功能研究进展 总被引：2，自引：0，他引：2
共轭亚油酸（CLA）是含有共轭双键的亚油酸家族的总称,在这个家族中至少有28个同分异构体,它们主要存在于反刍动物的脂肪中.其中含量最多,生物学功能最为广泛的c9t11 CLA,占整个CLA总量的80％～90％.其生物学功能包括抗肿瘤细胞生长、改善心血管系统功能、增强机体免疫力以及预防糖尿病等.其次为t1oc12 CLA,占CLA总量的3％～5％,其主要生物学功能为降低脂肪酸的合成,抑制脂肪细胞的分化与生长等.给反刍动物饲喂具有不同脂肪酸含量特征的油菜籽、长链不饱和脂肪酸等,或对体内硬酯酰辅酶A去饱和酶的活性进行调节,均可提高反刍动物组织中的CLA含量,从而生产出具有促进人体健康的功能性畜产品.未来的研究应该阐明共轭亚油酸中的共轭结构是如何发挥其生物学功能的,在其他营养物质中是否也存在具有生物学功能的结构形式. 相似文献
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为研究牧草物候期对其脂肪酸组成和放牧牦牛乳中共轭亚油酸（CLA）含量的影响及其相关关系,本研究在甘肃省甘南牧区选取平均体重为（234.9±10.5） kg的10头带犊甘南牦牛作为研究对象（自然放牧）,分别于牧草返青期、盛草期、枯草期采集试验牦牛采食牧草、乳和瘤胃液,分别测定瘤胃液、牧草中脂肪酸及乳脂中共轭亚油酸组成,并分析其相关关系,以期探明牧草物候期对牦牛瘤胃液和牧草中脂肪酸组成与放牧牦牛乳中共轭亚油酸含量的影响及其变化规律。结果表明：物候期显著影响了牧草中月桂酸、肉豆蔻酸、棕榈酸、硬脂酸、亚油酸、亚麻酸、总脂肪酸、多不饱和脂肪酸、多不饱和脂肪酸/总脂肪酸（P<0.05）,盛草期牧草中月桂酸、肉豆蔻酸、棕榈酸、亚油酸、亚麻酸、总脂肪酸、多不饱和脂肪酸、多不饱和脂肪酸含量/总脂肪酸均显著高于返青期和枯草期（P<0.05）;物候期显著影响了牦牛乳中共轭亚油酸异构体c9t11、共轭亚油酸异构体t10c12和共轭亚油酸总含量（P<0.05）,盛草期放牧牦牛乳中共轭亚油酸异构体c9t11、共轭亚油酸异构体t10c12和共轭亚油酸总含量显著高于返青期和枯草期（P<0.05）;物候期显著影响了牦牛瘤胃pH值、乙酸、丙酸、乙酸/丙酸、异丁酸、丁酸、异戊酸、戊酸、总挥发酸和反式11-油酸含量（P<0.05）,盛草期牦牛瘤胃乙酸、丙酸、丁酸、戊酸总挥发酸和反式11-油酸含量显著高于返青期和枯黄期（P<0.05）;牧草粗蛋白、粗脂肪、无氮浸出物、单宁酸、总脂肪酸和瘤胃液pH值与放牧牦牛乳中CLA含量显著正相关（P<0.05）,粗纤维和粗灰分与放牧牦牛乳中CLA含量显著负相关（P<0.05）,多不饱和脂肪酸（PUFAs）和瘤胃总挥发酸（TVFA）与放牧牦牛乳中CLA含量无显著相关关系（P>0.05）。 相似文献
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Satoshi KAWAHARA Shin-ichi TAKENOYAMA Kazuaki TAKUMA Michio MUGURUMA Kiyoshi YAMAUCHI 《Animal Science Journal》2009,80(4):468-474
We investigated the effects of dietary conjugated linoleic acid (CLA) on fatty acid composition and lipid oxidation in breast meat of broiler chickens. Broiler chickens (28-day-old females) were fed diets containing experimental oils at 20 g/kg diet for 28 days. The experimental oils consisted of either a 2:0, 1:1, or a 0:2 (wt : wt) ratio of safflower oil (high linoleic acid content) to a commercial CLA mixture. In this study, dietary CLA supplementation significantly increased the composition and content of CLA in chicken meat. The predominant CLA in meat from birds with supplemented diets was the cis -9, trans -11 isomer. The proportion of saturated fatty acid in meat significantly increased with increasing CLA supplementation, with a corresponding decrease in monounsaturated fatty acid. Dietary CLA also reduced thiobarbituric acid reactive substances (TBARS) values in raw meat during storage at 4°C for 5 days. These results provide evidence that CLA feeding is a practical strategy not only for adding nutritional benefits to chicken meat but also for improving meat quality including oxidative stability. 相似文献
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采用气相色谱法对牦牛酥油和普通奶油进行测试,分析其脂肪酸含量和组成,尤其是共轭亚油酸(CLA).结果表明:酥油中硬脂酸含量(83.23 g/kg)高于普通奶油(57.15 g/kg),棕榈酸含量(155.73 g/kg)比普通奶油(178.26g/kg)低;酥油中反式油酸(C18:1,t11)的含量是普通奶油的近8倍,酥油中总CLA含量是普通奶油的2倍多,尤其是C18:2,c9t11CLA异构体,在普通奶油中含量为3.38 g/kg,在酥油中为9.86 g/kg,是普通奶油的近3倍.相对于普通牛乳来说,牦牛乳具有更高的营养价值. 相似文献
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共轭亚油酸(Conjugated linoleic acid,CLA)具有诸多生理活性,天然的CLA主要来源于反刍动物产品。在日粮中添加富含多不饱和脂肪酸(Polyunsaturated fatty acid,PUFA)的饲料是提高反刍动物产品中CLA含量的一个重要方法。本文通过PUFA对反刍动物CLA机体、消化道及组织等不同代谢层次的影响进行了综述,提出了目前通过PU-FA提高反刍动物CLA中存在的问题,期望为生产中深入利用反刍动物的高CLA这一优势、提高其产品品质提供帮助。 相似文献
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Three Angus steers (410 kg) cannulated in the proximal duodenum were used in a replicated 3 x 3 Latin square to evaluate the effects of dietary lipid level and oil source on ruminal biohydrogenation and conjugated linoleic acid (CLA) outflow. Dietary treatments included: 1) typical corn (TC; 79.2% typical corn), 2) high-oil corn (HOC; 79.2% high-oil corn), and 3) the TC diet with corn oil added to supply an amount of lipid equal to the HOC diet (OIL; 76.9% TC + 2.4% corn oil). Duodenal samples were collected for 4 d following 10-d diet adaptation periods. Data were analyzed with animal, square, period, and treatment in the model and planned, nonorthogonal contrasts were used to test the effects of dietary lipid content (TC vs HOC and OIL) and oil source (HOC vs OIL) on ruminal biohydrogenation. Intake and duodenal flow of total long-chain fatty acids were increased (P < 0.05) by over 63% for diets containing more lipid regardless of oil source. Apparent ruminal dry matter and long chain fatty acid digestibilities were not altered (P > 0.05) by dietary lipid level or oil source. Ruminal biohydrogenation of total and individual 18-carbon unsaturated fatty acids was greater (P < 0.05) for diets with higher lipid content. Biohydrogenation of oleic acid was greater (P < 0.05) for HOC than OIL, but biohydrogenation of linoleic acid was lower (P < 0.05) for HOC than OIL. Duodenal flows of palmitic, stearic, oleic, linoleic, and arachidic acids were more than 30% greater (P < 0.05) for diets containing more lipid. Flow of all trans-octadecenoic acids was greater (P < 0.05) for diets containing more lipid. Corn oil addition increased (P < 0.05) the flow of trans-10 octadecenoic acid and the trans-10, cis-12 isomer of CLA by threefold compared to feeding high-oil corn. Feeding high-oil corn or adding corn oil to typical corn rations increased intake, biohydrogenation, and duodenal flow of unsaturated long-chain fatty acids. Compared with high-oil corn diets, addition of corn oil increased duodenal flow of trans-10, trans-12 and cis-12 isomers of octadecenoic acid and the trans-10, cis-12 isomer of CLA. The amount of cis-9, trans-11 isomer of conjugated linoleic acid flowing to the duodenum was less than 260 mg/d, a value over 20 times lower than flow of trans-11 vaccenic acid indicating the importance of tissue desaturation for enhanced conjugated linoleic acid content of beef. 相似文献
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In this experiment sunflower oil, soybean oil and fish oil were incubated in rumen-fistulated adult ewes (n = 5) to study conjugated linoleic acid (CLA) production in the rumen. The individual oils were incubated in nylon bags in the rumen on perlite carrier (40% oil, 60% carrier) over a period of 2, 4, 6, 8, 10 and 12 h for all treatments. During the incubation of each oil primarily the formation of the cis-9, trans-11 isomer of CLA could be observed. Both sunflower and soybean oils showed similar changes in the rumen. After the incubation of these two vegetable oils the proportion of linoleic acid decreased significantly as the duration of incubation increased in the rumen. These changes were accompanied by a significant increase in the amount of cis-9, trans-11 CLA. However, in the case of sunflower oil the rate of formation of the cis-9, trans-11 CLA isomer was significantly higher after the different incubation times as compared to soybean oil. Much lower amounts of CLA were formed when fish oil was incubated in the rumen. The level of cis-9, trans-11 isomer produced during these treatments was 10% less than the amount obtained with the other two oils of vegetable origin. Besides the cis-9, trans-11 isomer, trans-10, cis-12 CLA could also be detected during the incubation of the different oils in the rumen. However, the level of this isomer was low and did not show consistent differences among the treatments. The results of this experiment indicate that the fatty acid composition of the oils and the duration of incubation collectively determine the amount of CLA produced in the first compartment of the forestomach of ruminants. 相似文献
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Oleszczuk J Oleszczuk L Siwicki AK Skopińska-Skopińska E 《Polish journal of veterinary sciences》2012,15(2):403-408
Conjugated linoleic acids (CLA) are a group of polyunsaturated fatty acids (PUFA) with a single pair of conjugated double bonds. The major natural CLA isomer is 18:2 cis-9, trans-11 (c9, t11) linoleic acid, or rumenic acid (RA). Chemically synthesized CLA is also available, mostly as a mixture of RA and 18:2 trans-10, cis-12 (t10, c12) isomers in equal amounts (50:50). Consumption of ruminant meat (beef and lamb) and dairy products (milk and cheese) is the main source of dietary exposure to CLA. Despite numerous studies on animal and human models (tumorigenesis, obesity, immune response) it has not been established whether additional supplementation of CLA is of benefit. Moreover, some studies, conducted both in animals and in humans, reveal that CLA isomers may induce insulin resistance. Presently, balanced diet rich in CLA from natural sources is recommended. The purpose of this review was to sum up the results available in the literature. 相似文献