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脂肪酸囊泡(FAV)的中空壳核结构能够包埋活性分子。为改善FAV仅在其p Ka附近形成的缺陷,以拓宽FAV的应用范围,将安全性和温和性阴离子表面活性剂烷基磷酸酯钾盐(MAPK)添加到共轭亚油酸中,通过动态激光光散射(DLS)和透射电子显微镜(TEM)研究了囊泡化的pH窗口,发现9%MAPK存在时就可以在中性至酸性环境中形成杂化FAV,不明显改变原有FAV的形貌及粒径,且随着MAPK添加量的增大,杂化FAV的pH窗口有逐渐拓宽的趋势。这一结果显示了杂化FAV在化妆品和个人卫生护理用品等领域的应用前景。 相似文献
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囊泡是表面活性剂溶液中的一种特异聚集形态,它可以通过表面活性剂的复配形成,也可以在生物体内自发的形成.囊泡的微小尺寸和多层结构为纳米材料开发以及生物膜研究提供一种途径,因此受到科研人员的广泛关注.文章综述了囊泡的形成及其在医药和纳米粒子制备方面的应用. 相似文献
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以Mg(NO_3)2·6H_2O和Al(NO_3)_3·9H_2O为主要原料,采用共沉淀联合水热合成法制备了甲氨蝶呤插层镁铝层状双氢氧化物复合物(MTX-LDH),通过正交实验分析了主要工艺条件对MTX-LDH复合物载药率、粒径及其分散性的影响。结果表明:当反应温度为60℃、Mg(NO_3)2·6H_2O和Al(NO_3)_3·9H_2O的投入量分别为2.67和1.33 mmol、MTX和聚乙二醇400加入量分别为0.20 mmol和15 mL时,复合产物单分散性良好,粒径均值为175.6 nm,载药率达18.90%。利用FTIR、XRD、TG以及TEM对样品结构、热力学性质和微观形貌进行了测定。重点考察了MTX-LDH复合物在不同pH缓冲溶液中的释药性能,表明其具备pH响应型释放特性,在pH=5.8的弱酸环境中缓释效果良好,12h累积释药率为93.7%,并通过热力学释药模型确定其缓释机理为层板溶蚀与置换扩散并存的缓释机制。 相似文献
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聚乳酸硝苯地平缓释微球的制备与释药性能研究 总被引:1,自引:0,他引:1
以熔融缩聚制得的聚乳酸(PLA)作为载体,以聚乙烯醇为分散剂,二氯甲烷为溶剂,采用乳化-溶剂蒸发法制备聚乳酸硝苯地平(PLA/NFD)缓释微球。通过红外光谱(FT—IR)和生物显微镜对聚乳酸硝苯地平缓释微球进行了表征,并用紫外分光光度法探讨了聚乳酸硝苯地平缓释微球的释药性能。结果表明:聚乳酸硝苯地平缓释微球呈现以光滑完整的球形,且聚乳酸和硝苯地平药物能够有机地结合为一体。合成的聚乳酸硝苯地平球形微球具有明显的缓释作用,而且增大硝苯地平,聚乳酸投药比,会提高微球的释放度,但包封率下降。 相似文献
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目的:探索来源于人脐带间充质干细胞(hUC-MSCs)的工程化纳米囊泡(Nanovesicle,NVs)的制备与鉴定方法,为深入了解工程化NVs的生物学功能提供数据基础。方法:采用物理方式破碎hUC-MSCs以获取NVs,并采用改良的超速离心法进行分离和纯化;通过纳米颗粒跟踪分析(NTA)、透射电镜(TEM)观察、蛋白质免疫印迹(WB)及生物学活性分析方法鉴定NVs的特性。结果:建立的方法成功分离出NVs,TEM下观察到NVs呈中间凹陷的茶杯样结构;NTA结果显示NVs直径在100 nm左右;Western Blot实验证实NVs几乎不表达外泌体特异性蛋白TSG101;生物学活性实验表明NVs不能促进人皮肤成纤维(HSF)细胞增殖。结论:本研究建立的hUC-MSCs来源的NVs提取及鉴定方法可行,为NVs在未来的临床研究提供了数据基础。 相似文献
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Conjugated linoleic acid(CLA)is a kind of fatty acid with physiological activities and potential appli-cation prospect ,A synthesis method of conjugated linoleic acid and a purification technology were studied .CLA was prepared and purified by urea-complexation and conjugation using safflower oil as raw material,The purity of CLA and total recovery of the product was more than 95% and 48%,respectively,The main isomers produced in alkali-catalyzed conjugation were identified by gas chromatography (GC)linked to mass spectrometry(MS) and Fourier transform infrared spectroscopy(FTIR),The total amount of the two main isomers (9cis,11trans-and 10trans,12cis-CLA) determined by GC was more than 90% of the product. 相似文献
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Hidetaka Uehara Tomomi Suganuma Satoshi Negishi Yukihiro Uda Yoshinori Furukawa Satoru Ueno Kiyotaka Sato 《Journal of the American Oil Chemists' Society》2008,85(1):29-36
Thermal properties, powder X-ray diffraction patterns and FT-IR absorption spectra of crystals of two isomers of conjugated
linoleic acid (CLA), 9-cis, 11-trans-CLA (c9t11), 10-trans, 12-cis-CLA (t10c12) were examined. To search for polymorphic modifications, we carefully performed crystallization from melt and
solution phases, and isolated one type of crystalline form in c9t11 and t10c12. The melting temperature (T
m) was 14.9 °C, enthalpy of fusion (ΔH) was 38.7 kJ/mol, and entropy of fusion (ΔS) was 134 J/mol K for c9t11, and T
m = 19.8 °C, ΔH = 35.6 kJ/mol and ΔS = 122 J/mol K for t10c12. The X-ray diffraction and FT-IR measurements indicated O⊥ subcell packing in the crystals of c9t11 and t10c12, and long spacing values of 4.22 nm for c9t11 and 3.88 nm for t10c12.
The unique molecular structures of the two isomers of CLA are discussed in comparison to the polymorphism of oleic acid, petroselinic
acid, elaidic acid and linoleic acid, all of which are unsaturated fatty acids having the same carbon number of 18 as that
of the two CLA isomers. 相似文献
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碱法异构化亚油酸甲酯制备共轭亚油酸 总被引:1,自引:0,他引:1
该文探索在乙二醇溶剂中以氢氧化钠碱法异构化亚油酸甲酯制备共轭亚油酸的方法,适宜的异构化条件为m(氢氧化钠)∶m(亚油酸甲酯)∶m(乙二醇)=1∶5∶8.4,170℃反应4 h,亚油酸甲酯转化率和共轭亚油酸产率分别为92.4%和89.3%。该法比目前常用的亚油酸原料法的优越之处体现在:以氢氧化钠取代常用碱氢氧化钾,降低成本;以亚油酸甲酯取代亚油酸为原料,避免了原料本身大量消耗碱;反应初期避免原料大量皂化,减小了体系的传质阻力,因而减少了溶剂乙二醇消耗量。 相似文献
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Effects of feeding conjugated linoleic acid (CLA) to hens on progeny chick development and composition at hatch (NHC) and
three weeks of age (TWC) were assessed. CLA (0 or 0.5%, composed of mixed isomers of cis-9,trans-11 or trans-10,cis-12-CLA) was fed to hens with either safflower (SO) or olive oil (OO) (3 or 3.5%) to assure successful hatch for 2 weeks prior
to collection for incubation. Maternal CLA feeding had no effect on hatchability, but improved egg fertility (p < 0.05). Maternal feeding of CLA with SO increased 21 day-old progeny growth, while CLA with OO decreased growth (oil*CLA,
p < 0.05). In 25 day-old chicks (TWC), but not NHC, maternal CLA decreased the proportion of total body water (p < 0.05) and increased body ash (p < 0.05). While monounsaturated fatty acids were decreased and saturated fatty acids increased in eggs and NHC from hens fed
CLA, no differences in fatty acid composition were observed in chicks at 25 days of age from hens fed CLA. Maternal CLA feeding
resulted in the presence of c9,t11 and t10,c12-CLA in NHC, but only c9,t11 in the TWC. In conclusion, hens fed CLA led to improved fertility and altered body composition at 3 weeks of age. 相似文献
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红花油制取共轭亚油酸的研究 总被引:2,自引:0,他引:2
以新疆克拉玛依厂的红花油为原料,以丙三醇为溶剂,在KOH的碱性催化作用下,将红花油先转化成亚油酸钾;再利用异构化反应制得浅黄色的共轭亚油酸产品。对产品进行了薄层层析法和紫外分光光度法定性分析,并定量分析了红花油异构化反应的程度。本研究对红花油的深加工将起到很好的推动作用。 相似文献
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Sayed Amir Hossein Goli Miskandar Mat Sahri Mahdi Kadivar Javad Keramat 《Journal of the American Oil Chemists' Society》2009,86(5):453-458
Even though conjugated linoleic acid (CLA) is known to have some beneficial effects on the human body, its consumption has
decreased over the past 20 years due to the replacement of animal fats by vegetable oils. In this study, using the structured
lipid (SL) containing CLA, an experimental table margarine enriched with CLA was produced and stored for 3 months at two temperatures
prior to performing the relevant analyses. The GC results showed that the margarine fat had 10.6% CLA. The solid fat content
was the highest in week 0 in all samples, which then decreased during storage but the hardness increased. An increment in
dropping point was also observed in the samples. In week 0, all the samples had the β′ crystal as the predominant crystal
form but a crystal transformation from β′ to β was observed during storage. 相似文献
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Jayasimha Rayalu Daddam Harald M. Hammon Arnulf Trscher Laura Vogel Martina Gnott Gitit Kra Yishai Levin Helga Sauerwein Maya Zachut 《International journal of molecular sciences》2021,22(6)
Phosphoproteomics is a cutting-edge technique that can be utilized to explore adipose tissue (AT) metabolism by quantifying the repertoire of phospho-peptides (PP) in AT. Dairy cows were supplemented with conjugated linoleic acid (CLA, n = 5) or a control diet (CON, n = 5) from 63 d prepartum to 63 d postpartum; cows were slaughtered at 63 d postpartum and AT was collected. We performed a quantitative phosphoproteomics analysis of subcutaneous (SC) and omental (OM) AT using nanoUPLC-MS/MS and examined the effects of CLA supplementation on the change in the phosphoproteome. A total of 5919 PP were detected in AT, and the abundance of 854 (14.4%) were differential between CON and CLA AT (p ≤ 0.05 and fold change ± 1.5). The abundance of 470 PP (7.9%) differed between OM and SC AT, and the interaction treatment vs. AT depot was significant for 205 PP (3.5% of total PP). The integrated phosphoproteome demonstrated the up- and downregulation of PP from proteins related to lipolysis and lipogenesis, and phosphorylation events in multiple pathways, including the regulation of lipolysis in adipocytes, mTOR signaling, insulin signaling, AMPK signaling, and glycolysis. The differential regulation of phosphosite on a serine residue (S777) of fatty acid synthase (FASN) in AT of CLA-supplemented cows was related to lipogenesis and with more phosphorylation sites compared to acetyl-coenzyme A synthetase (ACSS2). Increased protein phosphorylation was seen in acetyl-CoA carboxylase 1 (ACACA;8 PP), FASN (9 PP), hormone sensitive lipase (LIPE;6 PP), perilipin (PLIN;3 PP), and diacylglycerol lipase alpha (DAGLA;1 PP) in CLA vs. CON AT. The relative gene expression in the SC and OM AT revealed an increase in LIPE and FASN in CLA compared to CON AT. In addition, the expression of DAGLA, which is a lipid metabolism enzyme related to the endocannabinoid system, was 1.6-fold higher in CLA vs. CON AT, and the expression of the cannabinoid receptor CNR1 was reduced in CLA vs. CON AT. Immunoblots of SC and OM AT showed an increased abundance of FASN and a lower abundance of CB1 in CLA vs. CON. This study presents a complete map of the SC and the OM AT phosphoproteome in dairy cows following CLA supplementation and discloses many unknown phosphorylation sites, suggestive of increased lipid turnover in AT, for further functional investigation. 相似文献
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Hamza Alaşalvar Hakan Erinç Fatma Salur Ayşe Özbey 《Journal of the American Oil Chemists' Society》2019,96(7):839-846
Conjugated linoleic acid (CLA) is commercially produced by alkali isomerization of linoleic acid (LNA). However, this method constitutes a relatively high content of undesirable CLA isomers. In present study, microwave-assisted and ultrasound-assisted alkali isomerization techniques were applied for production of CLA as an alternative to traditional alkali isomerization. This study was aimed to evaluate the isomerization degree of LNA, by using various process conditions such as microwave power, ultrasound amplitude, and their reaction times. The best conditions for LNA isomerization were a microwave power of 700 W and a reaction time of 6 h for microwave-assisted alkali isomerization and an ultrasound amplitude of 100% and a reaction time of 6 h for ultrasound-assisted alkali isomerization. Under determined conditions, microwave-assisted alkali isomerization (97.21%) resulted in a higher isomerization degree compared to ultrasound-assisted alkali isomerization (76.98%) while the content of undesirable CLA isomers in ultrasound-assisted alkali isomerization (0.62%) was lower than that of microwave-assisted alkali isomerization (1.87%). This study showed that application of the both techniques resulted in equal amounts of desirable CLA isomers. The content of desirable CLA isomers was 47.09% cis-9, trans-11 and 48.25% trans-10, cis-12 for microwave-assisted alkali isomerization and 36.34% cis-9, trans-11 and 40.02% trans-10, cis-12 for ultrasound-assisted alkali isomerization. 相似文献