微量元素与中药功效关系的探讨

中药中含有丰富的微量元素，其种类和含量与中药功效有着密切的关系。从微量元素与中药的滋补作用，解热作用．抗菌消炎作用和止血作用等四方面，论述了微量元素与中药功效的关系。     

叶黄素简介

叶黄素属类胡萝卜素,近年研究发现其具有保护视觉、抗氧化、抗癌等作用。本文从叶黄素的结构、性质、来源、生理功效、研究现状及应用前景等方面进行了介绍。     

罂粟籽挥发油化学成分研究

罂粟籽为罂粟的种籽,作为药用,主要用果汁及壳,具有止痛、镇咳等多种功效,但因其所含吗啡等生物碱具有显著成瘾性,故将其列为毒麻药品而严格管理和使用;罂粟籽则榨油供食用,具有一定的医疗保健作用。     

西红花中金属元素的分析

西红花为鸢尾科植物番红花(Crocus sativus L)的干燥柱头.具活血化瘀,凉血解毒,解郁安神等功效.采用原子吸收分光光度法(AAS)测定西红花中部分金属元素的含量,通过对其宏量元素及微量元素含量的测定结果,分析了西红花中金属元素及其生理作用与药用功效之间的关系.随着元素医学的不断发展,金属元素与中药药效关系及对生物体系的作用有待研究.     

Folin-Ciocalteu比色法测定石榴叶中多酚的含量

正石榴是石榴科石榴属落叶灌木,诸多研究表明,其果皮、种子、果汁、茎、叶等均含有各种对人体有益的营养成分,具有一定的保健和药用价值[1-6]。其中石榴叶很早就被发现具有收敛止泻、解毒杀虫的功效,在埃及作为传统药材[7]。现代研究显示,石榴叶还具有调节血脂水平、清除自由基、抗氧化、提高免疫力等作用[7-8],且这些活性效用均与其所富含的多酚类物质相关。但是,目前鲜见对石榴叶中多酚含量测定的报道,研究者多将焦点集中在石榴皮中多     

溪黄草总二萜提取工艺及抑制亚硝化反应的研究

唇形科香茶菜属植物溪黄草(Rabdosia serra(Maxim·)Hara)具有清热祛湿、凉血散瘀、抗肿瘤、抗菌、消炎及对肝脏的保护作用[1,2]。据文献报道,溪黄草中的对映-贝壳杉烷型二萜化合物,是其具有抗癌作用的主要功效成分[3-5]。其结构与冬凌草甲素极为相似,在同一波长处具有相似的紫     

肽的检测方法及化妆品中肽检测的计量需求

肽因具有良好的生物活性而在化妆品中得到越来越广泛的应用。介绍了化妆品中肽的类型及其作用,肽对改善皱纹、抗衰老和美白祛斑等方面有明显功效。当前社会对化妆品中肽的检测方法及计量学研究存在迫切需求,综述了目前检测肽常见的方法:凯氏定氮法、荧光检测技术、化学发光检测法、电泳法、比色法、酶联免疫吸附剂测定法、色谱法等。     

2,6-二氯靛酚滴定法测定蜂胶中维生素C

蜂胶是一种具有重要生理功效的天然药物和保健食品[1],是蜜蜂从植物芽孢和树干处采集的树脂,混入蜜蜂上颚腺分泌物和蜂蜡等形成的一种具有芳香味的黏性胶状固形物,其化学成分复杂,含有酚、酸、醇、酯、醚、萜、烯、甾醇及多种微量元素[2]。近年来,国内外学者所做的大量研究表明:蜂胶具有治疗心血管、糖尿病、皮肤病、胃肠疾病、抗癌、增强免疫、抗菌消炎等重要的生理功效[3],已经成为保健食品研究领域的热点。随着乙醇提取法、酶解法、超临界     

反萃分散液膜分离提取黄连中生物碱研究

黄连是一种常用的中草药,具有清热燥湿、泻火解毒之功效,其主要的活性成分为多种异喹啉生物碱,包括药根碱、巴马汀、小檗碱等,这些生物碱具有抗菌、消炎和抗肿瘤等作用~([1～2]).因此,从黄连中提取这些生物碱具有重要意义.     

未来的窗户

现代社会,人们的生活离不开玻璃,玻璃窗户为我们提供了阳光、热量。介绍了智能玻璃在控制阳光、自我清洁等方面的功效以及改善途径。     

青藏高原湖泊影响锂元素迁移和富集的矿物、元素及环境因素——以西藏郭扎错钻孔沉积物为例

作为我国战略性矿产的锂矿,主要赋存于青藏高原盐湖中。湖泊系统中,锂的富集和迁移规律关系到锂矿的高效提取和未来锂矿的储量估算。本文以西藏咸水湖郭扎错的钻孔沉积物为例,结合AMS14C年代和Mg元素含量变化,系统分析了孔隙水、碳酸盐矿物和硅酸盐矿物的锂含量变化,探讨了矿物、镁元素、环境变化和早期成岩作用等对锂元素迁移和富集的影响。郭扎错沉积物中锂和镁大部分存在于硅酸盐矿物中,锂和镁较高的相关性说明二者存在于相同的硅酸盐矿物中,如粘土矿物。大约90%的锂赋存在硅酸盐矿物中,约8.5%的锂赋存在碳酸盐矿物中,孔隙水中的锂含量占比仅约1.5%。碳酸盐矿物中Mg/Li摩尔比值为78–270,是孔隙水中10多倍,而硅酸盐矿物中的Mg/Li摩尔比值稳定在24–29之间。水–沉积物相互作用促进硅酸盐矿物中锂的释放,咸水环境下释放的锂多于淡水环境下。碳酸盐矿物中,锂和镁主要存在于方解石中。镁离子对锂离子的迁移具有阻碍作用,低温、高盐度下的阻碍作用更强。湖泊沉积物可能是湖水锂的一个重要来源。     

谈科学探究中的归纳与演绎

逻辑推理过程与事物的认识过程同时存在,科学探究离不开逻辑推理过程。归纳和演绎是认识过程中的两种逻辑推理形式,在学生的科学探究活动中,尤其是在提出问题、猜想与假设、设计实验方案与解释结论阶段,归纳和演绎发挥着重要的作用。本文重点论述了寻求现象原因的求异归纳推理、探寻化学物质通性及变化规律的不完全归纳推理、探求个别物质性质的演绎三段论、解释个别现象的演绎解释推理过程在科学探究中的重要作用。     

石柱黄连及根际土壤中矿质元素特征分析

研究石柱黄连不同器官及其根际土壤中矿质元素特征,探究黄连根茎矿质元素间及其与土壤环境的相关性。采用电感耦合等离子体质谱法(ICP-MS)、电感耦合等离子体发射光谱法(ICP-OES)及原子荧光光谱法(AFS)测定了15组石柱黄连植株和根际土壤中18种矿质元素含量,所得数据运用SPSS 22.0统计软件分析。石柱黄连根际土壤中锰、磷、镁、镉、汞等元素含量的变异性较大,部分采样点土壤中镉含量超过农用地土壤污染风险筛选值。在检测的18种元素中,黄连植株中钙、镁、磷、钾含量最高,其次是铁、锰、锌,再次是锶、铜、镍,最后是铅、钒、钴、镉、钼、铬、砷、汞。须根对大部分矿质元素的富集能力强于根茎或地上部;黄连根茎对锌的富集能力强于须根或地上部;地上部对钙、磷、钾、铬的富集能力强于须根或根茎。Spearman分析表明黄连根茎矿质元素间、黄连根茎与土壤中矿质元素有一定相关性,部分具有统计学意义(P＜0.05)。石柱黄连不同器官中矿质元素含量有明显差异,以此建立的指纹图谱可用于区分黄连根茎及须根的粉末样品;黄连根茎中矿质元素间主要表现为协同作用,黄连根茎与土壤中矿质元素既有协同作用又有拮抗作用。     

Analytical strategies to determine antibiotic residues in fish

The accelerated growth of aquaculture has resulted in a series of harmful effects to human health. The widespread and unrestricted use of antibiotics in this industry, to prevent bacterial infections, leads to remaining amounts in the aquatic environment. This has resulted in the emergence of antibiotic-resistant bacteria in aquaculture environments, in the increase in antibiotic resistance in fish pathogens as well as in the transfer of these resistance determinants to human pathogens. Moreover, the use of large amounts of antibiotics may lead to the presence of residual antibiotics in fish tissue and fish products. Fluoroquinolones, tetracyclines, penicillins, sulphonamides and other antibiotics, exhibiting activity against both Gram-positive and Gram-negative bacteria, are widely used for the treatment and prevention of diseases in fish. An extended and comprehensive review on the recent analytical methodologies concerning antibiotic residues in fish reported in the literature is provided in the present article. Emphasis is given on sample preparation regarding isolation and purification, chromatographic conditions and method validation according to legislation. Results of published assays are comparatively presented and criticised.     

UNDERSTANDING THE HYDROPHOBIC EFFECT

The hydrophobic effect is the common expression for processes where nonpolar groups in molecules are spontaneously removed from water. Thermodynamic analysis of hydrocarbon solubility in water, micellization and adsorption of surfactants show that the hydrophobic effect can be understood in terms of two contributions. The first contribution is attributed to the structuring, or rearrangement, of water molecules in the vicinity of a hydrophobe. This contribution is favorable, and hence increases the solubility of hydrocarbons in water, increases the cmc, and decreases the adsorption of surfactants. The second contribution is attributed to the formation of a cavity in the water in order to accomodate the hydrophobe. This contribution dominates over the first one and is unfavorable, i.e. it decreases the solubility of hydrocarbons in water, decreases the cmc, and increases the adsorption of surfactants. Thus, the cause of the hydrophobic effect is to be found in the large energy required to form a cavity in the water. On the other hand the temperature dependence of the hydrophobic effect is entirely determined by the water structuring, or rearrangement, in the vicinity of a hydrophobe.     

Staudinger reaction at in-bridgehead positions of phosphorus macrobicyclic compounds

Reaction of in,in-phosphite 1 with thiophosphoryl azide 2 affords in,in-dithiophosphate 3, in,in-thiophosphate-imidophosphate 4, and in,in-phosphite-imidophosphate 5. Compounds 4 and 5 are the first examples of the modification of in-bridgehead positions in macrobicyclic compounds with groups larger than methyl. The benzaldehyde arms of the in-substituent in 4 and 5 jut out of the cage bars. In 4 they are trapped between the macrocyclic arms to give the NMR spectra of a Cs-symmetric solution-state structure. In contrast, in 5 the benzaldehyde arms can move between the gaps of the cage. This results in 1H and 13C NMR spectra which are consistent for a compound with C3v symmetry. In,out-diimidophosphate 7 is obtained in moderate yield by reaction of in,out-phosphite 6 with thiophosphoryl azide 2. Its in-benzaldehyde moieties are not fixed between the cage arms, but can freely move from one gap to the next as is indicated by NMR measurements.     

Sources and Accumulation of Butyltin Compounds in Ganges River Dolphin,Platanista gangetica

Concentrations of butyltin compounds (mono-, di-, and tri-butyltin) were determined in dolphin ( Platanista gangetica ), fish, invertebrates and sediment collected from the River Ganges, India, in order to understand the contamination levels, sources, and potential for biomagnification in freshwater food chains. Total butyltin concentration in dolphin tissues was up to 2000 ng g⁻¹ wet wt, which was about 5–10 times higher than in their diet. The concentrations in fish and benthic invertebrates, including polychaetes, were 3–10 times greater than in sediment. The biomagnification factor for butyltins in river dolphin from its food was in the range 0.2–7.5. Butyltin concentrations in Ganges river organisms were higher than those reported for several persistent organochlorine compounds. Discharge of untreated domestic sewage was one of the major sources of butyltin residues in Ganges river biota. High concentrations of butyltin compounds in freshwater food chains suggest the need to assess their toxic effects in aquatic organisms and to regulate their use. © 1997 by John Wiley & Sons, Ltd.     

Effects of dilute acid and steam explosion pretreatments on the cellulose structure and kinetics of cellulosic fraction hydrolysis by dilute acids in lignocellulosic materials

Worldwide, yellows diseases impact plants important in human nutrition, the natural environment, and the culture and commerce of humans. Since the presumed pathogens, mycoplasma-like organisms (MLOs), have not been isolated in pure culture in vitro, their study must proceed by other experimental approaches. In a study of disease affecting grapevines in Europe and North America, polymerase chain reactions (PCR) and restriction analyses of PCR-amplified DNA were used to detect and differentiate strains of MLOs associated with grapevine yellows. MLOs were detected both in naturally diseased grapevines and in experimentally inoculated host plants. The data indicated an unexpected genomic diversity among grapevine-infecting MLOs, and supported their classification with MLOs in the aster yellows, X-disease, and elm yellows groups. The presence of diverse MLOs in grapevines provokes consideration that these MLOs may be present in overlapping geographic ranges and that multiple MLO infections may occur in individual plants, increasing the complexity of grapevine yellows epidemiology and control and the significance of sensitive MLO detection in planting stock and phytosanitary-regulated germplasm.     

An Investigation of the Trace Element Status of Bison in Wood Buffalo National Park and of Ranch-Raised Bison in Saskatchewan,Canada

Abstract

Trace metal levels were compared in ranched bison receiving a dietary supplement and in wild bison in Wood Buffalo National Park. Data collected in this study were also assessed with regard to information previously published on healthy wild bison resident in the Mackenzie Bison Sanctuary. Ninety percent of ranched animals contained lead, with mean levels of 0.06 and 0.10 ppm in liver and kidney, respectively, while lead was present in only 20% of samples from wild bison. Similarly, arsenic was more prevalent in ranched animals, though at levels below 0.05 ppm. Cadmium levels were significantly higher in the wild bison and traces of mercury were also more prevalent in the wild herd.

Levels of copper, manganese, selenium and zinc, which are considered essential nutrients, showed variations between the ranched and wild bison, but were within the range considered acceptable for cattle, with the exception of selenium. This was found to be lower in the wild herd.

Further research is required to define the nutritional requirements of healthy bison. Variations observed in this investigation could be attributed to a variety of factors, including age, diet, and health status, which cannot be differentiated based on the available samples.     

Platinum levels in urban soils from Palermo (Italy); Analytical method using voltammetry

A fast accumulation of platinum in the environmental and biological matrices was observed in the last years and concern arose about potential environmental and health risks.The toxicity of platinum species has been investigated in various studies, some of their, especially the chlorinated ones, are very toxic and allergenic. Information of the acute toxicity of some Pt-chlorinated salts and evidence of DNA damage due to Pt exposure have been observed both in vitro and in vivo.Taking into account what is written above, the development of reliable analytic methods to measure very low Pt concentrations is required. In this work was developed a reliable method for the determination of Pt in soils because of inherent difficulties in using conventional techniques, in particular, the ICP-OES technique. A determination of Pt using ICP-MS, for instance, is problematic, due to interfering signals. Differential pulse voltammetry (DPV/a) was employed by us for the determination of platinum in soils collected in Palermo area. Possible interferences by other environmental metals have been also evaluated.All samples show concentrations of Pt above average upper crust values; concentrations were found in the ranges 0.6–2240 μ/kg d.w. We carried out linear regression analysis between total Pt concentrations in soils obtained in this work and Pt concentrations in leaves of Nerium oleander measured in previous researches. The high correlation coefficient obtained confirms the geographical distribution of the considered pollutant in the Palermo area.