芦丁金属配合物的研究进展

芦丁及其衍生物具有广泛的药理活性。芦丁具有完整的大π键共轭体系,强配位氧原子与合适的空间构型,可与金属离子螯合成稳定的环状配合物。到目前为止,国内外合成的芦丁金属配合物,有些具有明显的生物活性,有些药理作用显著。芦丁与金属离子在一定条件下形成配合物后,还可应用于分光光度、荧光、极谱分析等,检测金属离子或者检测芦丁的含量。     

芦丁钙的制备

为了合成芦丁钙,采用芦丁与无水氯化钙在甲醇溶液中反应,用甲醇钠调pH=8.5,加热,回流,用TLC检测反应进程,当反应完全后,趁热过滤,蒸馏,滤液用聚酰胺层析柱层析,甲醇溶液梯度洗脱,收集设定区间洗脱液,旋蒸,得深棕黄色固体。通过元素分析、紫外光谱、红外光谱对产物进行了表征,结果表明,所合成的是芦丁钙配合物。     

曲克芦丁-钕(Ⅲ)配合物的制备及表征

以曲克芦丁为配体、Nd3+作为形成体制备曲克芦丁钕配合物,探索曲克芦丁与Nd3+反应生成配合物的适宜条件,通过紫外光谱、红外光谱、质谱等手段对其进行表征。结果表明:TXT中4-C=O的氧原子和5-OH的氧原子与Nd3+发生螯合生成Nd(TXT)2]3+,TXT与Nd3+反应的适宜条件为曲克芦丁与钕的物质的量之比为2∶1、p H=7.0、反应温度55℃、反应时间4 h。     

光度法研究铜离子和铁离子与芦丁的不同配位特性

研究了铜-芦丁配合物以及铁-芦丁配合物形成的最佳条件和热力学常数,铜(Ⅱ)和芦丁在pH=7～8的KH2PO4-NaOH缓冲溶液中可形成1∶2的稳定配合物,表观稳定常数为β2=4.351×1011,而芦丁和铁(Ⅲ)在pH=6的HAc—NH4Ac缓冲溶液中能形成最大配比为3∶1的混合配合物,不稳定。     

芦丁锑的合成及清除自由基活性研究

介绍了芦丁锑的合成方法.通过紫外光谱、红外光谱、氢谱、同步热分析对其结构进行了表征.通过DPPH法测定了芦丁锑清除自由基的能力,实验结果显示,芦丁锑清除自由基的能力比芦丁强.芦丁与锑离子在室温下可以反应生成稳定的配合物,提示在日常生活中经常食用一些含有芦丁的黄酮类食物,如柑橘、草莓、银杏、养麦等,可清除体内的自由基,使机体免受自由基的损伤,对降低人体内重金属离子起着重要的作用.     

芦丁铅的合成及清除自由基活性研究

芦丁与铅离子在室温下可以生成性能稳定的配合物。通过紫外光谱、红外光谱分析对其结构进行了表征。通过DPPH法测定了芦丁铅清除自由基的能力,实验结果显示,芦丁铅清除自由基的能力没有芦丁强。在日常生活中经常食用一些含有芦丁的黄酮类食物,如柑橘、草莓、银杏、荞麦等,可清除体内的自由基,使机体免受自由基的损伤,对降低人体内重金属离子的含量起着重要的作用。     

酞菁铕镨钕配合物的合成及表征

本文研究了铕酞菁、钕酞菁利镨酞菁配合物的合成、提纯与表征的方法。合成及表征结果表明,合成所得酞菁化合物通过元素分析可知具有纯度高;红外光谱表征推测结构可靠。紫外分析表明铕酞菁、钕酞菁和镨酞菁配合物特征吸收峰有相似之处。     

曲克芦丁-镝(Ⅲ)配合物的制备与表征

以TXT为配体、Dy3+作为中心离子制备曲克芦丁镝(Ⅲ)配合物,采用紫外光谱、红外光谱和质谱等对其进行表征。结果表明:配合物制备的适宜条件是nTXT∶nDy3+=2∶1、p H=7.0、T=55℃、t=4 h;配体中羰基上的氧原子与Dy3+形成配位键使其红外吸收峰移向低波数位1622 cm-1处,配合物在648 cm-1处和561 cm-1附近指纹区有Dy←O配体键伸缩振动吸收峰;曲克芦丁镝配合物的质核比为1646和1670,曲克芦丁镝配合物的分子量为1647.86;2个曲克芦丁分子中4位上的羰基氧原子和5位上的羟基氧原子分别1个Dy3+发生配位形成[Dy(TXT)2]3+配合物。     

钆配合物的合成及光电性能的研究

以磷钼酸和烟酸为配体,采用水热合成法合成了一种新颖的含稀土钆的配合物,并对该配合物进行了元素分析、红外、紫外、荧光、电化学、热重等一系列表征。结果表明,该配合物在218 nm和261 nm处有两个很强的紫外吸收峰;在323 nm光的激发下,配合物在377 nm处有一个强的荧光发射峰;在-0.6~0.6 V(以饱和甘汞电极为参比电极)的电势范围内,配合物出现了两对氧化还原峰,电化学性能良好。同时该配合物具有较好的热稳定性。     

槐花米中芦丁的抗氧化性及抑菌性研究

目的:研究槐花米中芦丁的抗氧化性及抑菌性。方法:以中药槐花米为原料,采用碱溶酸沉法提取其中的芦丁并精制,对精制物进行红外光谱分析;采用清除羟基自由基能力测定来分析研究芦丁的抗氧化性;采用滤纸片法以大肠杆菌和金黄色葡萄球菌为抑菌对象,分析芦丁的抑菌性。结果:芦丁浓度越高抗氧化性越强,芦丁的抗氧化性优于抗坏血酸;芦丁对大肠杆菌和金黄色葡萄球菌均有抑菌作用。结论:芦丁有较好的抗氧化性和抑菌性。     

Oxygen and Drug-Carrying Periodic Mesoporous Organosilicas for Enhanced Cell Viability under Normoxic and Hypoxic Conditions

Over the last decade, inorganic/organic hybrids have been exploited for oxygen-carrying materials and drug delivery. Its low-cost synthesis, controlled shape and size, and stability have made it a viable delivery strategy for therapeutic agents. Rutin (quercetin-3-O-rutinoside) is a bioflavonoid found in fruits and vegetables. Rutin has a variety of pharmaceutical applications, but its low water solubility reduces its stability and bioavailability. As a result, we introduce a new and stable nanosystem for loading a low-soluble drug (rutin) into oxygen-carrying periodic mesoporous organosilicas (PMO-PFCs). Over the course of 14 days, this nanosystem provided a sustained oxygen level to the cells in both normoxic and hypoxic conditions. At different pH values, the drug release (rutin) profile is also observed. Furthermore, the rutin-coated PMO-PFCs interacted with both healthy and malignant cells. The healthy cells have better cell viability on the rutin-coated oxygen-carrying PMO-PFCs, while the malignant cells have a lower cell viability.     

Rutin Modulates MAPK Pathway Differently from Quercetin in Angiotensin II-Induced H9c2 Cardiomyocyte Hypertrophy

Rutin is a flavonoid with antioxidant property. It has been shown to exert cardioprotection against cardiomyocyte hypertrophy. However, studies regarding its antihypertrophic property are still lacking, whether it demonstrates similar antihypertrophic effect to its metabolite, quercetin. Hence, this study aimed to investigate the effects of both flavonoids on oxidative stress and mitogen-activated protein kinase (MAPK) pathway in H9c2 cardiomyocytes that were exposed to angiotensin II (Ang II) to induce hypertrophy. Cardiomyocytes were exposed to Ang II (600 nM) with or without quercetin (331 μM) or rutin (50 μM) for 24 h. A group given vehicle served as the control. The concentration of the flavonoids was chosen based on the reported effective concentration to reduce cell hypertrophy or cardiac injury in H9c2 cells. Exposure to Ang II increased cell surface area, intracellular superoxide anion level, NADPH oxidase and inducible nitric oxide synthase activities, and reduced cellular superoxide dismutase activity and nitrite level, which were similarly reversed by both rutin and quercetin. Rutin had no significant effects on phosphorylated proteins of extracellular signal-related kinases (ERK1/2) and p38 but downregulated phosphorylated c-Jun N-terminal kinases (JNK1/2), which were induced by Ang II. Quercetin, on the other hand, had significantly downregulated the phosphorylated proteins of ERK1/2, p38, and JNK1/2. The quercetin inhibitory effect on JNK1/2 was stronger than the rutin. In conclusion, both flavonoids afford similar protective effects against Ang II-induced cardiomyocyte hypertrophy, but they differently modulate MAPK pathway.     

Extraction and Recovery of Rutin from Acerola Waste using Alcohol-Salt-Based Aqueous Two-Phase Systems

Extraction of rutin from acerola waste was investigated using alcohol-salt-based aqueous two-phase systems (ATPS). Initially, the partitioning was studied using model systems with pure and commercial rutin. The impact of the ATPS constituents and composition, initial amount of rutin, temperature and addition of electrolytes was evaluated. Rutin can be recovered either in the alcohol-or-salt-rich phase depending on the salt used. To validate the optimization process, rutin extraction from acerola waste was carried out further. The results obtained with the real samples are in close agreement with the model systems and validate the optimization tests and support their applicability in bioresource-related processes.     

From Metal‐Metal Bonding to Supra‐Metal‐Metal Bonding Directed Self‐Assembly: Supramolecular Architectures of Group 10 and 11 Metals with Ligands from Mono‐ to Poly‐Pyrazoles

The supramolecular architectures of pyrazole ligands with polynuclear metal centers have established a wide variety of constructing motifs. This review focuses on the metal‐metal bonding and Supra‐Metal‐Metal Bonding directed self‐assembly of supramolecular architectures of pyrazole ligands ranging from simple mono‐pyrazoles and derivatives to bipyrazoles and polypyrazoles with group 10 and 11 elements. The utility of the constructing motifs (μ‐pyrazolato‐N,N′)₂ doubly‐bridged dimetal corners in the metal‐metal‐bonding directed self‐assembly approaches with spontaneous deprotonation from bipyrazole to tripyrazole and tetrapyrazolyl calix[4]arene ligands, metallomacrocyclic and cage‐like complexes have been synthesized. The proton switching programmable self‐assembly strategy using pyrazole‐based bifunctional ligands has been developed by Yu. They have obtained organic homo‐ or hetero‐metallic supramolecular complexes from macrocycles, cages, to one dimensional polymers.     

微柱高效液相色谱法测定苦荞中芦丁的研究

研究了用微柱高效液相色谱法测定苦荞中芦丁的方法。苦荞中的芦丁用 80 %甲醇加热回流提取 ,以WatersXterraTMRP1 8( 1.0× 5 0mm ,2 .5 μm)色谱柱为固定相 ,1%的醋酸和甲醇为流动相 ,在该色谱条件下 ,苦荞中主要的芦丁在 1.0min内可达到基线分离 ,用紫外二极管矩阵检测器检测 ,方法可用于苦荞中的芦丁的测定 ,结果满意。     

超声条件下碱提取酸沉淀法从槐米中提取芦丁的研究

以新鲜的槐米为原料,65℃下充分干燥,研细后采用超声条件下碱石灰煮沸盐酸酸化沉淀法来提取芦丁。探讨了反应温度、反应液的pH值、溶剂用量及反应时间对产物芦丁提取率的影响。得出提取的最佳条件为:控制反应温度为70~75℃,碱提取时pH=9、酸沉淀时pH=4,溶剂用量以6倍于原料为宜,提取3次,反应时间3.5 h。制得的芦丁为浅黄色针状晶体,提取率17.83%,熔点176~178℃。     

Fabrication of electrospun antioxidant nanofibers by rutin‐pluronic solid dispersions for enhanced solubility

In this study, solid dispersions (SDs) and electrospinning combined methods were used to increase the bioavailability and solubility of a water insoluble drug. Pullulan (PUL) nanofibers containing rutin‐Pluronic SDs (PUL&RU@PF) were fabricated by electrospinning. Rutin was efficiently loaded with Pluronic SDs using a facile mixing method and the prepared SDs indicated that 4% w/v Pluronic concentration provided the optimal drug loading efficiency. Scanning electron microscopy (SEM) verified that the morphology of the complex nanofibers had a uniformly smooth surface with a porous structure. The amorphous state of rutin was examined by XRD and DSC. Moreover, rutin in the electrospun PUL‐rutin‐Pluronic complex structure displayed a fast release profile and equivalent antioxidant ability compared to that of raw rutin. In conclusion, PUL&RU@PF may be a promising alternative for enhanced solubility and UV stability with remaining rutin's inherent antioxidant ability. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44859.     

Microwave Accelerated Transglycosylation of Rutin by Cyclodextrin Glucanotransferase from Bacillus sp. SK13.002

Rutin was subjected to intermolecular transglycosylation assisted with microwave irradiation using cyclodextrin glucanotransferase (CGTase) produced from Bacillus sp. SK13.002. Compared with the conventional enzymatic method for rutin transglycosylation (without microwave irradiation), microwave-assisted reaction (MAR) was much faster and thus more efficient. While the conventional reaction took dozens of hours to reach the highest conversion rate of rutin and yield of transglycosylated rutin, MAR of rutin transglycosylation completed within only 6 min providing almost the same conversion rate of rutin and yield of products consisting of mono-, di-, tri-, tetra-, penta-glucosylated rutins. The optimum transglycosylation conditions for microwave irradiation were 40 °C and 60 W with the reaction system consisting mainly of the mixture of 0.3 g rutin (0.49 mmol) pre-dissolved in 15 mL methanol, 1.8 g maltodextrin in 15 mL of 0.2 M sodium acetate buffer (pH 5.5) and CGTase (900 U). Results from this study indicated that MAR could be a potentially useful and economical technique for a faster and more efficient transglycosylation of rutin.     

芦丁脂质体的制备与药物包封率的测定

采用薄膜分散法,制备包封率高、粒径均匀、稳定性好的芦丁脂质体,并建立芦丁脂质体中芦丁含量和包封率的测定方法。以包封率为主要指标,通过正交设计优化芦丁脂质体的制备工艺,同时采用反相高效液相色谱法进行芦丁含量和包封率测定。结果表明,薄膜分散法制备的脂质体平均包封率为66.50%,外观均匀、稳定性良好。建立的反相高效液相色谱法能将芦丁与辅料分离良好,芦丁浓度在4～40μg/L范围内与峰面积呈现良好的线性关系（r=0.999 2,n=5）,平均回收率为99.0%,可用于测定芦丁脂质体的药物含量与包封率。     

广南天料木茎抗氧化活性研究

以抗坏血酸(Vc)、二叔丁基羟基甲苯(BHT)和芦丁(Rutin)为阳性对照,利用酶标仪,采用二苯代苦味肼基自由基(DPPH)法、铁离子还原总抗氧化力(FRAP)法两种微量体外抗氧化活性分析方法对广南天料木茎加速溶剂萃取物及常规溶剂提取物进行评价。研究表明,乙酸乙酯加速溶剂萃取物(ASE-EtOAc,EC50=20.8 mg/L)清除DPPH自由基的能力最强,但弱于阳性对照。二氯甲烷加速溶剂萃取物(ASE-DCM)还原Fe3+能力最强〔FRAP值=(793.3±45.7)mol TE/g〕,强于阳性对照BHT,弱于阳性对照Vc和Rutin。常规水提取物(W)清除DPPH自由基的能力和还原Fe3+能力最弱。综合比较发现,常规正丁醇提取物(NBA)抗氧化能力较强、制备简单,具有更为广阔的研究与应用前景。