黑蒜促进血管生成作用

目的:通过转基因斑马鱼体内模型和人脐静脉内皮细胞体外模型,研究黑蒜对血管生成的促进作用。方法:采用绿色荧光蛋白标记血管的转基因flk-1:GFP系斑马鱼作为体内评价模型,在胚胎发育过程中,同时加入血管生成抑制剂(PTK787)与黑蒜提取液(0.2~3.2 μL/mL),观察斑马鱼胚胎节间血管和肠下静脉的生成情况;利用人脐静脉内皮细胞作为体外模型,借助细胞增殖检测实验,通过检测细胞活性,研究黑蒜提取液对人脐静脉内皮细胞增殖的影响。结果:黑蒜提取液可显著(p<0.05)改善由PTK787引起的胚胎节间血管和肠下静脉紊乱,增加斑马鱼胚胎节间血管和肠下静脉数量,并呈现出剂量依赖性,当黑蒜提取液浓度提高至3.2 μL/mL时,由PTK787抑制的胚胎节间血管和肠下静脉数目恢复至正常水平。另一方面,黑蒜提取液可剂量依赖性地提高人脐静脉内皮细胞的活性,促进人脐静脉内皮细胞的生长。结论:黑蒜在体内和体外模型上均体现出显著的促进血管生长的作用。     

基于斑马鱼模型研究鱿鱼生殖腺磷脂抗MPTP诱发帕金森病的活性

目的：探究鱿鱼生殖腺磷脂是否具有抗1-甲基-4-苯基-1,2,3,6-四氢吡啶盐酸盐（1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine，MPTP）诱发帕金森病的活性。方法：将受精后1 d（day post fertilization，dpf）的斑马鱼胚胎脱膜，设置空白对照组、50 μmol/L MPTP处理组、50 μmol/L MPTP与不同质量浓度（3、10、20 μg/mL）鱿鱼生殖腺磷脂共处理组。4 dpf时用荧光显微镜观察并记录各实验组转基因斑马鱼Vmat:GFP的多巴胺神经元发育情况和转基因斑马鱼Fli1:GFP的脑部血管发育情况；5 dpf时用Zebrabox斑马鱼行为分析仪分析野生型斑马鱼AB的行为变化，并通过实时荧光定量聚合酶链式反应检测帕金森病相关基因的表达情况，包括α-突触核蛋白、E3泛素连接酶、PTEN诱导假定激酶1、酪氨酸羟化酶编码基因。结果：与空白对照组比较，MPTP处理组斑马鱼多巴胺神经元缺失、脑部血管损伤，出现帕金森状行为，帕金森病相关基因表达异常；与MPTP处理组比较，不同质量浓度鱿鱼生殖腺磷脂与MPTP共处理组斑马鱼表现出多巴胺神经元缺失比例、脑部血管损伤程度降低，帕金森状行为缓解，相关基因异常表达趋于正常。     

核磁共振磷谱法测定乳制品中的磷脂含量

为了测定乳制品中的磷脂含量，建立了基于核磁共振磷谱（31P NMR）的磷脂分析方法，并采用内标法对磷脂进行了定量。利用建立的方法对不同哺乳期母乳（初乳、过渡乳、成熟乳）、奶粉（全脂奶粉、婴幼儿配方奶粉）、富含乳磷脂的乳清蛋白粉、大豆磷脂及鸡蛋磷脂中的磷脂组成及含量进行了分析。结果表明：9种磷脂标准品的检出限范围为48.97~85.76 μg/mL，定量限范围为97.94~171.52 μg/mL，具有合理的加标回收率（83.40%~108.52%）和精密度（相对标准偏差小于15%）。母乳中总磷脂含量平均为19.27 mg/100 mL，随着哺乳期的延长总磷脂含量逐渐降低。不同来源的样品中磷脂的组成有较大差异，母乳中含量最高的磷脂类型为鞘磷脂，其他样品中的磷脂主要类型为磷脂酰胆碱。     

南美白对虾虾头中磷脂提取工艺的优化

以南美白对虾虾头为原料,研究利用正己烷-异丙醇混合溶剂提取虾头中的磷脂。以磷脂相对提取率为评价指标,在单因素试验的基础上进行正交试验,确定优化提取工艺条件为:正己烷与异丙醇的混合比为3:1(V/V)、料液比l:8(g/mL)、提取时间2h、提取温度40℃,此条件下与经典氯仿-甲醇法比较,相对提取率达98.11%。磷脂丙酮不溶物含量为85.4%,乙醚不溶物含量为0.2%,两项指标均高于一级浓缩磷脂的标准。通过薄层色谱分离定性,共有5种磷脂,其中4种分别为磷脂酰乙醇胺、磷脂酰胆碱、神经鞘磷脂和磷脂酰丝氨酸,剩余一种尚未确证。正己烷-异丙醇提取法安全、有效,为充分利用虾头等废弃物资源,从中提取磷脂提供了新的方法。     

酸性电解水对南美白对虾中多酚氧化酶活性的影响

酸性电解水（acidic electrolyzed water,AEW）作为一种新型的杀菌保鲜技术已经被应用于海产品的保 鲜方面,实践表明AEW对南美白对虾的黑变有抑制效果。为了探究其作用机理,将南美白对虾中多酚氧化酶 （polyphenoloxidase,PPO）进行提取纯化,并研究AEW对PPO的抑制效果及抑制类型。十二烷基硫酸钠-聚丙烯酰 胺凝胶电泳结果显示,PPO的提纯效果较为理想;动力学研究发现,AEW对PPO活力具有显著抑制效果,且其作用 大小与AEW添加量呈明显的剂量-效应关系。AEW对PPO抑制类型为混合型抑制,抑制常数Ki为0.64 mmol/L。实验 结果为进一步探明AEW抑制南美白对虾黑变的作用机理提供了理论基础。     

核桃仁中抑制血管紧张素转化酶活性部位筛选研究

筛选核桃仁对血管紧张素转化酶(ACE)的抑制作用部位。用HPLC为检测手段,马尿酰-组氨酰-亮氨酸(HHL)为反应底物,ACE作为反应用酶,反应所生成的马尿酸为检测指标,未加酶抑制剂的反应为空白对照,卡托普利为阳性对照。应用本方法比较了核桃仁不同溶剂提取物对ACE抑制活性。水提脱脂核桃粉的ACE抑制活性最强,其IC50为2.87 mg/mL。脱脂核桃粉的水提取物有较好的ACE抑制活性。     

超高效液相色谱-串联质谱法测定圆椒中甘油磷脂含量

建立圆椒中磷脂含量测定的超高效液相色谱-串联质谱方法。样品用异丙醇-氯仿-水体系作为提取溶剂,液液萃取法净化,采用HILIC亲水作用色谱柱（2.1 mm×100 mm,1.7 μm）体系分离磷脂,电喷雾电离-串联四极杆质谱测定。分别以磷脂酰胆碱（C28:0）、溶血磷脂乙醇胺（C14:0）、溶血磷脂胆碱（C14:0）、磷脂酰甘油（C28:0）、磷脂酰甘油酸（C28:0）、溶血磷脂丝氨酸（C16:0）为对照进行相对定量。实验对提取溶剂和净化方法进行选择,以抽提得到磷脂种类最多、含量最高为前处理方法,并对该方法进行适应性检验。结果表明,6 种磷脂在10～1 000 ng/mL之间线性良好,检出限为2～300 ng/mL,定量限为10～1 000 ng/mL。在125、250 ng/mL和375 ng/mL的添加水平上,回收率在68.06%～84.17%之间,相对标准偏差介于3.40%～9.60%之间。该方法为圆椒磷脂测定提供了可靠的平台,为基于膜脂代谢的圆椒冷害研究提供基础。     

基于UPLC-Triple-TOF MS/MS对巴氏杀菌乳中磷脂成分的分析

基于超高效液相色谱-串联四极杆飞行时间高分辨质谱（ultra-high performance liquid chromatography-triple quadrupole-time of flight tandem mass spectrometry,UPLC-Triple-TOF MS/MS）法对巴氏杀菌乳中的磷脂成分进行分析鉴定。采用色谱柱ACQUITY UPLC? BEH C18（2.1 mm×100 mm,1.7 μm）,以流动相A水-甲醇-乙腈（1∶1∶1,V/V）和流动相B异丙醇-乙腈（1∶1,V/V）进行梯度洗脱,在电喷雾电离正模式下采集数据。依据高分辨质谱提供的保留时间、准分子离子、二级碎片等脂质分析数据,并结合标准品碎裂方式等信息,共鉴定出磷脂分子68 种。其中,磷脂酰胆碱22 种,占比7.98%;磷脂酰乙醇胺17 种,占比56.60%;磷脂酰丝氨酸10 种,占比1.70%;磷脂酰肌醇7 种,占比1.33%;鞘磷脂12 种,占比32.39%。本研究采用灵敏度高、精密度及稳定性良好的UPLC-Triple-TOF MS/MS方法实现了对牛乳中磷脂的全面定性与定量分析。此方法检测出的牛乳磷脂信息完整、磷脂种类多于其他检测技术,可为牛乳的磷脂研究提供数据基础。     

南极磷虾磷脂的组成及其抗氧化活性

为研究南极磷虾磷脂的组成及抗氧化活性,采用硅胶柱层析法分离制备南极磷虾磷脂,对其磷脂组成和磷脂脂肪酸组成进行分析,通过测定自由基清除能力和还原能力系统评价南极磷虾磷脂的抗氧化活性。结果表明,纯化获得的南极磷虾磷脂的磷脂含量为（93.78±3.18）g/100 g;南极磷虾磷脂主要为磷脂酰胆碱和磷脂酰乙醇胺,分别占比（90.60±1.03）%和（5.08±1.10）%;南极磷虾磷脂中多不饱和脂肪酸含量丰富,且主要为二十碳五烯酸（eicosapen?taenoic acid,EPA）和二十二碳六烯酸（docosahexaenoic acid,DHA）,分别占总脂肪酸含量的（31.75±0.24）%和（19.35±0.10）%。南极磷虾磷脂具有良好的自由基清除能力和还原能力,其清除ABTS+自由基和DPPH 自由基的IC50 值分别为15.78 mg/mL 和14.87 mg/mL,且其还原能力呈浓度依赖效应。南极磷虾磷脂的抗氧化能力明显优于大豆磷脂和卵黄磷脂。     

基于高效薄层色谱法的胡麻卵磷脂质量分析

目的：建立胡麻卵磷脂的高效薄层色谱质量分析方法。方法：将卵磷脂供试品及磷脂酰胆碱标准品溶于氯仿-甲醇（3∶2,V/V）,以氯仿-甲醇-水（65∶25∶4,V/V）为展开系统,考察不同显色剂、展开系统、点样量、薄层板、检视方式、温度、相对湿度对卵磷脂供试品中不同组分分离的影响,进行高效薄层色谱定性分析;在确定的色谱条件下,将卵磷脂供试品及磷脂酰胆碱标准品进行展开,扫描磷脂酰胆碱峰面积,绘制标准曲线,外标法测定卵磷脂供试品中磷脂酰胆碱的含量。结果：卵磷脂供试品各组分分离情况良好,适于定性分析;卵磷脂供试品中磷脂酰胆碱的含量为63.33%,板间、板内精密度实验相对标准偏差（relative standard deviation,RSD）分别为1.82%和3.73%,稳定性实验RSD为1.60%,加标平均回收率为98.5%。结论：建立的方法快速准确、重复性好,可为卵磷脂质量分析提供新的技术参考。     

Effect of soy lecithin in enhancing fruit juice/sauce quality

Phosphatidylcholine is a major component of biological membranes and is an important mediator of physiological functions in mammals. In addition to biosynthetic routes of availability, phosphatidylcholine is also derived from the diet. The levels of phosphatidylcholine are quite low in fruits and fruit products. As the fruits ripen, the phospholipids are degraded into neutral lipids causing a drastic decline in phospholipid content. In the present study, we have evaluated the effects of external supplementation of soy lecithin on physico-chemical properties of tomato juice and sauce, as well as grape juice. The levels of protein, soluble solids and ash content were significantly enhanced by the addition of lecithin. The bulk viscosity of tomato juice and the sauce preparation was also enhanced by addition of lecithin. The yellow color values of the juice and sauce preparations were enhanced by lecithin. In grape juice preparations, the addition of lecithin did not cause any negative effects, but enhanced the solids content of the juice. Juice preparations with added lecithin were more stable than the controls. Lecithin may form complexes with pectin, lipids and other carbohydrates, affecting the food property and stability by various mechanisms.     

Natural lecithins and phosphorylated acylglycerols as inhibitors of autoxidation of fats and oils

Both natural phospholipids (soybean or rapeseed lecithin) and phosphorylated acylglycerols (produced by treatment of diacylglycerols with phosphorus pentoxide or metaphosphoric acid) inhibit the oxidation of polyunsaturated fatty acid esters in rapeseed, sunflower seed or soybean oils, but only higher phospholipid additions (more than 0.2%) have pronounced effect on the stability under storage conditions. Partially hydrogenated oils are stabilized similarly as original liquid oils. The inhibitory activity of synthetic phospholipids is particularly high in presence of trace metal compounds, such as copper, iron or manganese. The chelating activity is nearly the same in the case of phosphatidic acids, their ammonium salts, phosphatidylcholine or phosphatidylethanolamine. The hydroperoxide decomposing activity is, however, much higher in nitrogen-containing phospholipids than in the corresponding phosphatidic acids. The content of oxidized fatty acids is lower in phospholipids than in triacylglycerols.     

槐花黄酮磷脂复合物制备及其对植物油氧化稳定性的影响

以槐花黄酮和大豆卵磷脂为原料制备黄酮磷脂复合物,以黄酮与磷脂的复合率为评价指标,通过单因素实验考察微波功率、反应时间、黄酮初始质量浓度和投料比(磷脂∶槐花黄酮质量比)对复合率的影响,由正交试验得到最优条件。研究了黄酮磷脂复合物的理化性质、溶解性及对植物油氧化稳定性的影响。结果表明,黄酮磷脂复合物的最佳制备工艺为:以乙醇为反应溶剂,微波功率为200 W,反应时间为40 min,黄酮质量浓度为2 mg/mL,投料比为2∶1,黄酮磷脂复合物复合率为79.98%。红外光谱和紫外光谱分析表明,黄酮与磷脂未形成新的化合物而是通过分子间作用力形成的复合物。与黄酮相比,复合物在水和在正辛醇中溶解性都有明显改善。添加黄酮磷脂复合物可以延缓葡萄籽油和核桃油的氧化反应。槐花黄酮磷脂复合物对核桃油的抗油脂氧化效果更好。本实验为槐花黄酮的进一步资源化开发利用提供了一定的技术依据。     

HPLC-ELSD法测定大豆磷脂中磷脂酰胆碱和溶血磷脂酰胆碱含量

该研究探讨采用HPLC–ELSD(蒸发光散射检测器)法测定大豆磷脂中磷脂酰胆碱和溶血磷脂酰胆碱含量。结果表明,选用硅胶色谱柱(150 mm×4.6 mm,5μm),磷脂酰胆碱(PC)和溶血磷脂酰胆碱(LPC)分别在0.5 mg/mL~8.0 mg/mL和0.4 mg/mL~6.0 mg/mL范围呈良好线性关系;PC和LPC平均回收率为99.42%和99.83%,相对标准偏差(RSD)分别为1.44%和1.21%。该法对大豆磷脂PC和LPC分析均具有良好精密度和重复性。     

磷脂强化乳脂肪体系对易氧化营养素包埋稳定性的影响

通过添加外源性大豆卵磷脂的方法保护牛乳均质后的脂肪球膜磷脂层，并利用新生成乳脂肪球分别包埋和保护富含多不饱和脂肪酸的鱼油、VE和β-胡萝卜素3 种易氧化营养素。结果表明，外源性磷脂的添加使牛乳均质过程中形成了结构完整、粒径更小、表面电位绝对值更大的油滴。在油脂加速贮藏实验过程中，富含磷脂和鱼油的2 种均质加工乳可减缓鱼油初级和次级氧化的程度，油脂氧化的初期阶段产生的脂质氢过氧化物含量最终分别为1.28 mmol/mL和1.79 mmol/mL，显著低于无外源性磷脂添加的2.81 mmol/mL。2 种磷脂强化乳在次级氧化阶段产生的丙二醛分别为4.29 nmol/mL和6.64 nmol/mL，显著低于无外源性磷脂添加的15.87 nmol/mL。磷脂强化乳中的VE保存率和β-胡萝卜素的保存率在贮藏实验的12 d后分别达到90.80%和71.02%，显著高于无外源磷脂添加的均质乳（80.63%和64.54%），该工艺方法可降低VE和β-胡萝卜素的降解程度。     

A method for separation and quantification of phospholipid classes in human milk

A simple, isocratic method for separating the major phospholipid classes of human milk by HPLC is described. Resolution of phosphatidylinositol, phosphatidylserine, phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylcholine, and spingomyelin from human milk phospholipids was achieved in 30 min on a silica column. Total phospholipids were injected in 50 microliter of chloroform:diethyl ether (1:2, vol/vol) and eluted with a solvent mixture of acetonitrile:methanol:sulfuric acid (100:3:.05, vol/vol/vol) at a flow rate of 2.5 ml/min. Fractions were collected and each phospholipid class quantified by analysis of inorganic phosphorus after sulfuric acid digestion. A repeatability study with 19 samples had a coefficient of variation of 5.3%. The analytical recoveries of phospholipid standards averaged 98%. Recoveries varied with phospholipid class; variation was greatest with spingomyelin.     

Short communication: Effects of dietary deoiled soy lecithin supplementation on circulating choline and choline metabolites,and the plasma phospholipid profile in Holstein cows fed palm fat

Dietary lecithin is a source of choline. Our objective was to evaluate the effects of dietary deoiled soy lecithin feeding on circulating choline, choline metabolites, and the plasma phospholipid profile in lactating dairy cows fed fractionated palm fatty acids. In a split-plot Latin square design, 16 Holstein cows (160 ± 7 d in milk; 3.6 ± 1.2 parity) were randomly allocated to a main plot receiving a corn silage and alfalfa haylage-based diet with palm fat containing either moderate or high palmitic acid content at 1.75% of ration dry matter (moderate and high palmitic acid containing 72 or 99% palmitic acid in fat supplement, respectively; n = 8/palm fat diet). Within each palm fat group, deoiled soy lecithin was top-dressed at 0, 0.12, 0.24, or 0.36% of ration dry matter in a replicated 4 × 4 Latin square design with 14-d experimental periods. A 14-d covariate period was used to acclimate cows to palm fat feeding without lecithin supplementation. Blood sampling occurred during the final 3 d of each experimental period. Plasma choline and choline metabolites were quantified using liquid chromatography and mass spectrometry. Plasma phospholipids were profiled using time-of-flight mass spectrometry. Whereas no effects of treatments were detected for plasma choline or methionine, lecithin feeding increased the plasma concentrations of choline metabolites trimethylamine N-oxide and dimethylglycine (24 and 11%, respectively). Plasma phosphatidylcholine (PC) and sphingomyelin (SM) concentrations increased with deoiled lecithin feeding (e.g., PC 16:0/22:6 and SM d18:1/18:3). Lecithin supplementation also increased plasma lysophosphatidylcholine (LPC) concentrations (e.g., LPC 18:0) while reducing plasma phosphatidylethanolamine (PE) concentrations (e.g., PE 16:0/20:5). Although increases in microbial-derived trimethylamine N-oxide suggest gastrointestinal lecithin degradation, elevations in plasma dimethylglycine, PC, LPC, and SM suggest that choline availability was improved by lecithin feeding in cows, thus supporting enhanced endogenous phospholipid synthesis.     

Autoxidation of stored soybean lecithin

Soybean phospholipid concentrates, generally called lecithins, can be stored for long time in a refrigerator or even at room temperature, without apparent changes of sensory properties, and their peroxide value usually remains low. This behaviour is related to the antioxidant activity of phospholipids in refined vegetable oils [1] which was attributed to their synergistic effect in presence of tocopherols [2, 3]. Both the low peroxide content and the inhibitory activity may be explained, at least partially, by the hydroperoxide decomposing activity of phospholipids [4], the rate of hydroperoxide decomposition being proportinal to the square root of the hydroperoxide content [5]. Therefore, we have analysed several samples of lecithin to find out whether the presence of phospholipids only affects the rate of hydroperoxide accumulation or the formation of total oxidation products, respectively.     

高效液相色谱-蒸发光检测器法测定鸡蛋中卵磷脂的含量

建立高效液相色谱-蒸发光检测器法测定鸡蛋中卵磷脂含量的分析方法。以Intersil SIL-100A 色谱柱（4.6 mm×100 mm, 5 μm）为分离柱,甲醇-乙腈-异丙醇为流动相,流速0.8 mL/min,柱温30 ℃,以空气作为雾化气,气体流速1.7 L/min,漂移管温度45 ℃。结果表明,磷脂酰胆碱和磷脂酰乙醇胺在0.052～1.031 mg/mL和0.041～0.823 mg/mL范围内与峰面积有良好线性关系,鸡蛋中磷脂酰胆碱和磷脂酰乙醇胺精密度的相对标准偏差（RSD）分别为2.55%和2.50%,加标回收率分别为93.0%～101.8%和96.7%～106.7%,表明该方法重复性好、准确度高。测定已知磷脂含量的鸡蛋样品,结果显示蒸发光检测器的测定结果比紫外检测器测定结果更符合真值,实验建立的方法可以准确定量鸡蛋中卵磷脂的含量,是测定蛋黄卵磷脂成分的理想方法。