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Six multiparous Holstein cows ranging from 7 to 19 wk postpartum were in a switchback design to determine effects of feeding high grain diets on lipoprotein concentration and composition in blood. Percents concentrate, alfalfa haylage, and corn silage of control and high grain diets were 50, 83; 25, 9; and 25, 8 dry matter. Milk yield (kg/day), milk fat percentage, and fat yield (g/day) averaged 27.7, 3.58, 997 and 30.2, 2.45, 729 for control and high grain treatments. Very low density, low density, and high density lipoproteins were isolated by gel filtration of total lipoproteins obtained by ultracentrifugation. Lipoprotein concentrations in blood plasma of cows fed the control or high grain diets were similar. Triglyceride, phospholipid, cholesterol, and cholesterol ester contents of each lipoprotein class were not altered by treatment. High grain feeding increased octadecadienoic fatty acid content of low density and high density lipoprotein cholesterol esters and decreased octadecenoic and octadecatrienoic acids. The trend was similar for the very low density lipoprotein fraction. Phospholipid octadecenoic acid decreased in all lipoprotein fractions but only significantly for high density lipoproteins. It is unlikely that differences in lipid composition of plasma lipoproteins caused alterations in lipoprotein metabolism leading to fat depression in this and other similar studies.  相似文献   

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芥蓝籽油脂肪酸组分GC-MS分析   总被引:3,自引:0,他引:3  
采用索氏提取法提取芥蓝籽油,样品甲酯化后,经CC—MS分离与分析,鉴定出19种脂肪酸组分。主要成分包括α-亚麻酸(31.64%)、亚油酸(16.08%)、花生一烯酸(15.94%)、油酸(15.79%)、棕棕榈酸(5.93%)、硬脂酸(3.15%)等,其中饱和脂肪酸含量合计11.80%,不饱和脂肪酸含量合计85.790k,  相似文献   

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本文介绍了一种以EA/BA/MMA/NMA为单体制备稳定的高固含量丙烯酸酯乳液的方法,并就不同复合单体组合、乳化剂、交联剂及引发剂的用量对乳液聚合稳定性的影响进行了讨论.结果表明:复合乳化剂、交联单体和引发剂的最佳用量分别为单体总量的3%、2%和0.5%.  相似文献   

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用于高固含量喷墨打印纸涂布的新型高岭土颜料   总被引:1,自引:0,他引:1  
喷墨打印是一种非击打式数字印刷方法。最近几年,家庭和办公室喷墨打印机用量大幅增长.其低价和打印色调的提高是这种增长的主要因素。数码摄影是彩色打印进入家庭的最主要推动力之一。由于打印头轻巧紧凑,故喷墨打印也可与其他印刷方法结合起来在线使用.预计喷墨打印在彩色印刷中将会有较大的增长.  相似文献   

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本文介绍了一种以EA/BA/MMA/NMA为单体制备稳定的高固含量丙烯酸酯乳液的方法,并就不同复合单体组合、乳化剂、交联剂及引发剂的用量对乳液聚合稳定性的影响进行了讨论。结果表明:复合乳化剂、交联单体和引发剂的最佳用量分别为单体总量的3%、2%和0.5%。  相似文献   

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本文研究了紫甘蓝花色苷(RCA)对动脉粥样硬化兔血脂的调节作用。新西兰大白兔分为正常对照组、模型对照组、RCA低、中、高剂量组和阳性对照组(n=8)。正常对照组以普通饲料喂养,其他组均以高脂饲料喂养,6周后,RCA低、中、高三个剂量组分别灌胃30、60、90 mg/(kg·d)体重的花色苷,阳性对照组灌胃5 mg/(kg·d)体重的辛伐他汀(simvastatin),模型对照组灌胃2 m L/(kg·d)体重生理盐水。实验第6周和10周分别检测兔子血清甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)等指标,10周后取血处死,取主动脉作病理形态学观察。结果发现辛伐他汀和RCA能明显降低兔子血清TG、TC、LDL-C的含量,病理切片显示,紫甘蓝花色苷可减轻动脉粥样硬化斑块等病理损伤,揭示RCA对高血脂和动脉粥样硬化具有重要防护作用,且呈现剂量-效应关系。  相似文献   

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为提高牦牛骨的利用率,实现高值化利用,本文采用GC-MS和IUPAC法测定了牦牛骨脂质组成和理化指标,并进行分析。脂质组学分析共检出20种脂肪酸,其中SFA(饱和脂肪酸)含量占脂肪酸总量的41.75%,FA n:1(单不饱和脂肪酸)为53.01%,PUFA(多不饱和脂肪酸)1.46%,其他为3.79%。在负离子模式下共检测出4种脂质:Car(乙酰左旋肉碱)、SM(鞘磷脂)、PC(磷脂酰胆碱)和TAG(三脂酰甘油及中性脂肪),含量依次是PC>SM>TAG>Car。理化指标结果表明:牦牛腿骨脂质的脂肪酸稳定性较好且饱和脂肪酸较多。从牦牛腿骨中检出了两种物质:α-三烯酚和γ-三烯酚。油脂的氧化稳定性显示,牦牛骨油脂的诱导时间为5.56 h,牦牛骨的油脂氧化稳定性比较高,具有较强的抗氧化效果。脂肪酸与骨健康密不可分,而牦牛骨脂质脂肪酸含量丰富,因此,牦牛骨可以作为维护骨健康的潜在的营养剂。  相似文献   

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成熟度对甘蓝膳食纤维单糖组成及抗氧化活性的影响   总被引:2,自引:0,他引:2  
研究成熟度(成熟度A~D分别为最早成熟期采摘样品及每隔5 d采摘的样品)对甘蓝膳食纤维含量、单糖组成及抗氧化活性的影响。结果表明,随着甘蓝的成熟,可溶性膳食纤维(soluble dietary fiber,SDF)含量逐渐降低,非水溶性膳食纤维(insoluble dietary fiber,IDF)和总膳食纤维(total dietary fiber,TDF)含量则先增加后降低。不同成熟度甘蓝膳食纤维单糖组成均为葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖、鼠李糖、阿拉伯糖,但各单糖的相对含量对成熟度差异显著。随着成熟度增加,组成甘蓝SDF的单糖中,葡萄糖醛酸含量持续降低;葡萄糖与半乳糖含量显著增加;半乳糖醛酸、鼠李糖和阿拉伯糖含量变化呈抛物线,且在成熟度B时达到最高。随着甘蓝的成熟,甘蓝IDF的葡萄糖醛酸和半乳糖醛酸含量显著增加;葡萄糖和半乳糖含量在前期无变化,从成熟度D开始显著降低;阿拉伯糖含量变化呈抛物线,并在成熟度D达到最高;而鼠李糖含量始终保持恒定。随着甘蓝的成熟,其SDF与IDF的1,1-二苯基-2-三硝基苯肼自由基清除能力和三价铁还原抗氧化能力增强,而2,2’-联氮-二(3-乙基苯并噻唑啉-6-磺酸)自由基清除能力在成熟度C达到最强。  相似文献   

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Lipids from bamboo shoots (Phyllostachys pubescens), peeled and divided from top to base, were extracted and fractionated into three classes, and each class separated into constituent components by thin-layer chromatography (TLC). Fatty acid composition and amount of separated lipids were determined. Total lipids (TL) ranged from 800 (top) to 380 mg (base) per 100g fresh weight and the ratio of nonpolar lipids (NPL):glycolipids (GL):phospholipids (PL) was about 17:27:56. The main fatty acids of the three lipid classes were palmitic, linoleic and linolenic acids, but composition was remarkably different among these fractions. The fatty acid composition of triglycerides (TG) was similar to the original NPL. Palmitic acid was almost all located in 1-, 3-position, linoleic acid mainly located in 2-position of TG, while linolenic acid was distributed in each position. Digalactosyl diglyceride (DGDG) and monogalactosyl diglyceride (MGDG) were the main components of GL; the average of the former had about 37% linoleic and 29% linolenic acids, while the latter had about 25% linoleic and 62% linolenic acids. Bamboo shoots contained 9 PL fractions, the major being phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE). PC contained about 48% linoleic, 31% palmitic and 11% linolenic acids, and PE also had the similar tendency as PC.  相似文献   

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以西伯利亚鲟鱼卵为原料,比较不同提取方法对鲟鱼卵脂质提取率、脂肪酸及脂质组成的影响。采用索氏提取、酶辅助有机溶剂和超临界CO2三种不同的方法提取鲟鱼卵中的脂质,并分析鲟鱼卵脂肪酸组成及脂质组成。结果显示,不同提取方法对所得到的鲟鱼卵脂质的提取率和脂肪酸的相对含量有显著的影响(P<0.05),对鲟鱼卵脂质的脂肪酸种类和脂质组成没有显著影响(P>0.05)。索氏提取法的提取率为(23.71±1.82)%,中性蛋白酶酶解辅助有机溶剂法的提取率为(15.47±1.21)%,超临界CO2萃取法的提取率为(10.43±2.16)%。鲟鱼卵脂质中含有17 种脂肪酸,包括6 种饱和脂肪酸,4 种单不饱和脂肪酸,7 种多不饱和脂肪酸,其中总不饱和脂肪酸含量达到70%以上,多不饱和脂肪酸含量达到17%以上。不同提取方法提取鲟鱼卵脂质中均含有甘油三酯、胆固醇、极性脂质,其中甘油三酯相对含量达到89%以上。  相似文献   

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采用高效液相色谱法对甘蓝内叶、外叶、漂烫及真空干燥后的硫苷含量进行了成分鉴定及组分分析.结果表明,甘蓝内叶与外叶的组分相同,通过HPLC-ESI-MS共鉴定出5种脂肪族硫苷(3-甲基硫氧丙基GS,2-羟基-3-丁烯基GS,2-丙烯基GS,3-丁烯基GS,4-戊烯基GS)和1种吲哚族硫苷(3-吲哚基甲基GS),甘蓝中主要硫苷成分为2-羟基-3-丁烯基GS,2-丙烯基GS,3-吲哚基甲基GS及3-甲基硫氧丙基GS,内叶和外叶中硫苷含量分别为1 972 μg/g干重和1 941 μg/g干重,漂烫和真空干燥后硫苷的保存率分别为87.7%和37.4%.  相似文献   

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Inductively coupled plasma optical emission spectrometry was used to determine the elements present in Chinese cabbage (Beta vulgaris). The accuracy of the method was confirmed by analysis of a certified reference material of spinach leaves. The study involved 57 samples that were collected in 13 Brazilian cities. Average concentrations of elements found per gram of Chinese cabbage were as follows: 3.44 mg g−1 sodium, 5.09 mg g−1 potassium, 1.25 mg g−1 phosphorous, 0.85 mg g−1 calcium, 0.49 mg g−1 magnesium, 2.79 μg g−1 manganese, 9.50 μg g−1 iron, 0.74 μg g−1 copper, 14.28 μg g−1 zinc, and 6.44 μg g−1 strontium. Principal component analysis and hierarchical cluster analysis demonstrated that there is no systematic difference in the mineral composition between the cabbage samples that were analyzed.  相似文献   

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Cocoabean callus cultures were established and grew satisfactorily on an agar medium for more than 2 yr. Cell suspension cultures were initiated from the callus. The fresh weight of cells increased over 20-fold in 14 days. The lipid content of callus and cells was 5.3 and 6.5%, respectively. The fatty acid composition of cocoa callus and cell suspension cultures resembled that of immature cocoabeans since they contained high amounts of linoleic acid. Stereospecific distribution of fatty acids in triglycerides from cocoa callus and cells was similar to that of ripe cocoabeans. Exogenous acetate and fatty acids were readily incorporated into lipids by cocoa cell suspension cultures. Exogenous stearic acid increased triglyceride content twofold but did not change fatty acid composition of triglycerides. Coconut water alone or in combination with sucrose also increased triglyceride content with a concomitant increase in oleic acid from 10% to 33% and a decrease in linoleic acid from 37% to 19%.  相似文献   

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Seeds of 11 sorghum cultivars ( Sorghum bicolor ) from Argentina were analysed for proximate composition, fatty acids and sterols. Oil, protein, carbohydrate and ash contents varied between 41 and 66 g kg−1, 111 and 156 g kg−1, 670 and 730 g kg−1 and 13·8 and 20·6 g kg−1 of dry matter, respectively. Fatty acid profiles revealed that the major acids were palmitic (15·1–24·8%), oleic (29·9–41·8%) and linoleic (35·9–51·3%). Unsaponifiable matter was examined for sterols. Sitosterol was the prominent component in all cultivars (43·8–57·9%), followed by campesterol (18·7–29·1%) and stigmasterol (12·4–20·5%).  相似文献   

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Sardine (Sardina pilchardus) lipids have important nutritional characteristics because of their high level of ω3 fatty acids. Studies of the lipid composition of this pelagic species, studies were carried out monthly during one year. Total lipids ranged between 1.2% and 18.4% (w/w). The nonpolar lipids were dominant, mainly composed of triacylglycerols and highest in the fatty season. Phosphatidylcholine (PC), and phosphatidylethanolamine (PE) were the principal polar lipids. They were both high in ω3 polyenoic fatty acids mainly 20:5ω3 and 22:6ω3. PC and PE were isolated and their fatty acid profiles determined; PE was higher in 22:6ω3 than PC.  相似文献   

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熊涛  李军波  彭飞  关倩倩 《食品科学》2015,36(11):172-176
以2、5、8 g/100 mL食盐添加量的传统自然发酵泡菜为研究对象,比较了3 种不同食盐质量浓度的传统自然发酵泡菜中优势菌系结构、卤水pH值和总酸、底物和代谢产物、亚硝酸盐含量的变化。结果表明:乳酸菌主导整个泡菜发酵过程,蔗糖一直被代谢利用,葡萄糖和果糖含量逐步增加,发酵结束时乳酸大量积累。食盐质量浓度对泡菜发酵前期有显著影响,2 g/100 mL食盐质量浓度的泡菜中乳酸菌的繁殖代谢最快,发酵结束时pH值最低,总酸含量最高;5 g/100 mL食盐质量浓度能较好地抑制有害微生物的繁殖,最快通过亚硝峰,产生的乙醇量最高;8 g/100 mL食盐质量浓度抑制了泡菜中乳酸菌的繁殖代谢,使泡菜的成熟期延迟,对蔗糖的利用率最低。  相似文献   

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