中药炮制机理研究的思路与方法——以咖啡豆的烘焙原理研究为例

中药炮制是中药学的特色和优势,也是最具我国自主知识产权的学科之一.中药炮制研究的核心是阐明中药炮制机理,这也是制约中药现代化的关键节点.目前大部分中药的炮制机理尚不明确,有待进行系统深入的研究.咖啡豆需要烘培后才可以制成饮料,这个高温烘培过程类似于中药的炮制过程.近年来,国内外专家对咖啡豆高温烘培过程化学成分变化及其机理进行了深入研究,各种新方法和新技术得到广泛应用,取得了系列研究成果,这些研究成果为中药炮制机理研究提供了多种新思路和新方法,也为中药炮制机理的研究和阐明提供了重要示范.     

润滑材料摩擦化学*

外界机械能能够引发的化学反应称为摩擦化学反应。当两个接触的表面进行相对运动时,在界面发生物理和化学变化或反应。润滑材料在服役过程中发生的摩擦化学反应对于其性能的具有正面或负面的影响。通过了解摩擦化学反应机理和反应产物结构及组成,对于理解润滑材料失效机制、性能调控原理具有指导意义。本文针对润滑材料的主要类型：润滑添加剂、纳米添加剂、离子液体、稀土、陶瓷、类金刚石薄膜、有机薄膜、聚合物,综述了近几十年来在相关润滑材料方面开展和取得的摩擦化学研究结果。     

对我国热化学发展的浅见

热化学是化学热力学的一部分,它的主要任务是研究化学变化或物理过程中能量变化的规律。当物质的状态发生改变时,常常伴随着产生热效应,通过量热法可测定出这些热效应值,如燃烧热、熔化热、溶解热、混合热、比热、吸附热以及各种反应热等。这些热效应数据,在解决化学热力学问题时,可计算生成焓、生成自由能、熵等热力学函数,从而可以判别一个化学反应的方向和反应的限度。同时,在物质结构、生理学、地球化学等基础理论研究中,如探讨晶体结构、生物变化、矿物成因等,也有很重要的作用。此外,在热机、化工和其它工程设计中,也都是不可缺少的重要数据。因     

现代仪器分析技术在中药炮制机理研究中的应用

现代分析技术以仪器分析为主,大量先进的现代仪器分析技术已经较广泛地应用于中药炮制机理研究领域,对阐明中药炮制的机理,提高中药饮片的质量控制水平起了很大的推动作用.本文对多种现代仪器分析技术进行介绍,并对其在中药炮制机理研究中的应用现状作一综述.     

凝聚态化学研究中的动力学振动光谱理论与技术

化学变化的本质是化学键的形成与断裂。凝聚态化学的主要特征是分子内的物理与化学过程与周围环境之间的动态相互作用和动力学耦合,不仅会影响化学键形成与断裂的化学反应平衡与反应速率,还会改变化学反应的走向。动力学振动光谱技术是探测凝聚态体相中与表面上各种微观分子细节最为有力的当代谱学表征技术之一。与脉冲核磁技术类似,科学家们使用一组精心设计的激光脉冲在凝聚态体系中激发复杂的光学响应,所产生的信号中包含了比传统吸收光谱丰富得多的反应机理、分子与溶液结构、分子运动、电荷与能量传递等微观信息。近年来,各种动力学振动光谱被运用于凝聚态化学的各个领域,尤其是在溶液态和表界面态领域,获得了一系列突破性进展,并且处于不断发展的过程之中。在本文中,我们将回顾及展望动力学振动光谱技术的基本概念、实验方法和理论框架,以及它们在凝聚态及表面态化学中的重要应用。     

凝聚液态水溶液中的化学反应

液态水是进行化学反应的最重要介质与溶剂之一,也是研究在凝聚(液)态中进行化学反应的主要对象。在不同的外界条件下(特别是极端条件下),液态水的组成、结构与性能会发生很大的变化,促使在其中进行的化学反应呈现不同的特点,因而形成了温和条件下、水热条件下(Hydrothermal condition)与超临界水热条件下(Supercritical water codition)三大类型反应的凝聚态化学。本文立足凝聚态,讨论了在温和(一般)条件下,液态水与水溶液的组成、结构与性能对发生于其中的化学反应(包括溶解与结晶反应、盐类复分解反应、酸碱反应、沉淀反应、成胶与晶化反应、水解反应、氧化-还原反应以及配位化学反应)的影响,包括对反应物存在状态与化学活性,化学反应的过程与机理,反应的中间与最后产物的组成、结构等造成的影响,以及产生的结果与规律等有关的反应化学。通过这些讨论我们提出应从凝聚态的角度看待发生于液态水溶液中的化学反应,并希望这种新视角对研究在其他类型液体(诸如有机溶剂、离子液体、分子熔体等)中进行的化学反应时有所帮助,同时能加强彼此间的交流、讨论与批判,协力为推动以液态为主要研究对象的凝聚态化学的研究与学科建设提供有益的基础。     

微量元素分析中药炮制研究

根据国内近年来有关向量元素分析在中药炮制研究中所取得的成绩及存在问题，探讨了微量元素分析对中药炮制理论及方法研究的意义。     

光合作用与诺贝尔化学奖

光合作用不仅是规模极其宏伟的化学过程,而且是地球上最重要的化学反应。通过介绍诺贝尔化学奖曾经7次授予光合作用的研究者,简要回顾人类对光合作用的研究历程。同时,阐述叶绿素结构及光合作用化学机理的最新研究成果。     

链锁反应

门捷列夫在化学的定义里,特别强调,将与化学变化进程同时发生的现象的研究,应该列入化学课程之内。在我们这一世纪的开始,化学家们在很多化学变化的过程中碰到了各种各样的反常。例如,研究光化学反应(即是在光的作用下的化学反应)的工作者发现:一个被吸收的光量子(光能的基本单位)在某些条件下能够引起大量反应产物的生成。这个观察结果无论如何也不能和叫做爱因斯坦光化学等当量的定律结合起来。按照这个定律,一个光量子应该只引起化学变化的一个单元动作。在几次企图     

高分子物理学系统讲演

第八講 高聚物的化学特性 1.裂解反应比較小分子与高分子的化学反应,首先应該区別反应平衡与反应动力学,对反应平衡来說,高分子化合物的化学变化与低分子化合物有同样的规律,如聚乙烯醇和乙二醇分子上的OH基团能进行相同的化学反应。而同时高分了化合物的化学变化又有一些显著的特点与小分子化合物不同,例如长链分子出現一种新的反应,就是裂解。裂解反应是高分子化合物的一个特征。它与聚合反应有相似的过程,以两种不同的方式来实现。第一种是无规断链,卽高分子中的任何一个链节都有同样被断裂的可能性。这与縮聚反应很     

Identifying the chemical markers in raw and wine-processed Scutellaria baicalensis by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple statistical strategies

Herb processing is a typical pharmaceutical preparation process for traditional Chinese medicine. After processing, its clinical applications and pharmacological effects vary greatly, which is most commonly attributed to the changing chemical properties between raw herb and processed products. In this work, a total of 53 chemical compounds were detected, among which 17 compounds were identified as discriminatory chemicals between raw and wine-processed Scutellaria baicalensis, and 10 components were identified as chemical markers with a cumulative content contribution of 88.75%. In addition, this work revealed that the best wine-processed time was 18 min by investigating the changes of chemical markers in S. baicalensis during processing. This work demonstrated that ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple statistical strategies is an effective approach for screening and identifying discriminatory chemical markers in complex traditional Chinese medicine.     

土壤无机元素与中药品质关系研究进展

综述了近几年土壤无机元素与中药品质关系的最新研究进展,主要包括土壤无机元素影响中药品质的机制研究、土壤无机元素影响中药化学成分的研究、土壤无机元素与中药道地性关系的研究,以及土壤无机元素与中药毒性关系的研究,并指出了目前研究中存在的主要问题和今后研究的主要方向。     

Study on Angelica and its different extracts by Fourier transform infrared spectroscopy and two-dimensional correlation IR spectroscopy

In order to develop a rapid and effective analysis method for studying integrally the main constituents in the medicinal materials and their extracts, discriminating the extracts from different extraction process, comparing the categories of chemical constituents in the different extracts and monitoring the qualities of medicinal materials, we applied Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy and two-dimensional correlation infrared spectroscopy (2D-IR) to study the main constituents in traditional Chinese medicine Angelica and its different extracts (extracted by petroleum ether, ethanol and water in turn). The findings indicated that FT-IR spectrum can provide many holistic variation rules of chemical constituents. Use of the macroscopical fingerprint characters of FT-IR and 2D-IR spectrum can not only identify the main chemical constituents in medicinal materials and their different extracts, but also compare the components differences among the similar samples. This analytical method is highly rapid, effective, visual and accurate for pharmaceutical research.     

A golden phoenix arising from the herbal nest — A review and reflection on the study of antimalarial drug Qinghaosu

Qinghaosu (QHS) and its derivatives are a new generation of antimalarial drugs characterized by fast action, high efficacy, and good tolerance. This feature article states the discovery of QHS from traditional Chinese medicine qinghao (Artemisia annua L.) and reviews the progress during the past four decades in the research of phytochemistry of A. annua, chemical reactions and biotransformation of QHS, chemical synthesis and biosynthesis of QHS, synthesis and antimalarial activity of QHS derivatives and analogs, pharmacological studies, clinical application, and the antimalarial mechanism. Undoubtedly, QHS is an example of the value of traditional Chinese medicine in modern medicinal research.     

High‐throughput LC–MS method for the rapid characterization of multiple chemical constituents and metabolites of Da‐Bu‐Yin‐Wan

Traditional Chinese medicine is the clinical experience accumulated by Chinese people against diseases. Da‐Bu‐Yin‐Wan is a famous traditional Chinese medicine formula consisting of Phellodendri amurensis Rupr., Anemarrhenae asphodeloides Bge., Radix Rehmanniae Preparata and Chinemys reevesii . In this study, ultra high performance liquid chromatography with electrospray ionization quadrupole time‐of‐flight high‐definition mass spectrometry with the control software of Masslynx (V4.1) was established for comprehensive screening and identification of the chemical constituents and serum metabolites of Da‐Bu‐Yin‐Wan in vivo and in vitro. Consequently, 70 peaks in the methanol extract from Da‐Bu‐Yin‐Wan and 38 peaks absorbed into rat blood were characterized. The 70 constituents in vitro included alkaloids, flavonoids, polysaccharide, limonoids, flavonoid, etc. And the 38 constituents consist of 22 absorbed prototypes and 16 metabolites of Da‐Bu‐Yin‐Wan absorbed in vivo. We fully clarified the chemical constituents of Da‐Bu‐Yin‐Wan and provided a scientific strategy for the screening and characterization of the chemical constituents and metabolites of traditional Chinese medicine in vitro and in vivo.     

Identification and analysis of chemical constituents and rat serum metabolites in Suan‐Zao‐Ren granule using ultra high performance liquid chromatography quadrupole time‐of‐flight mass spectrometry combined with multiple data processing approaches

Suan‐Zao‐Ren granule is widely used to treat insomnia in China. However, because of the complexity and diversity of the chemical compositions in traditional Chinese medicine formula, the comprehensive analysis of constituents in vitro and in vivo is rather difficult. In our study, an ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry and the PeakView® software, which uses multiple data processing approaches including product ion filter, neutral loss filter, and mass defect filter, method was developed to characterize the ingredients and rat serum metabolites in Suan‐Zao‐Ren granule. A total of 101 constituents were detected in vitro. Under the same analysis conditions, 68 constituents were characterized in rat serum, including 35 prototype components and 33 metabolites. The metabolic pathways of main components were also illustrated. Among them, the metabolic pathways of timosaponin AI were firstly revealed. The bioactive compounds mainly underwent the phase I metabolic pathways including hydroxylation, oxidation, hydrolysis, and phase II metabolic pathways including sulfate conjugation, glucuronide conjugation, cysteine conjugation, acetycysteine conjugation, and glutathione conjugation. In conclusion, our results showed that this analysis approach was extremely useful for the in‐depth pharmacological research of Suan‐Zao‐Ren granule and provided a chemical basis for its rational.     

Identification and characterization of the chemical constituents of Simiao Wan by ultra high performance liquid chromatography with mass spectrometry coupled to an automated multiple data processing method

The chemical constituents of Simiao Wan (SW), a traditional Chinese medicine preparation, are difficult to determine and remain unclear. To more efficiently detect ions, a multiple data processing approach has been used in the characterization of the compounds. In this study, a rapid and sensitive method based on ultra high performance liquid chromatography with mass spectrometry and the multiple data processing approach was established to characterize the chemical constituents of SW. Ultra high performance liquid chromatography with mass spectrometry coupled with the multiple data processing approach could efficiently remove nonrelated ion signals from accurate mass data. We report the application of the multiple data processing approach for comprehensive detection and rapid identification of chemical constituents of SW. Of note, the total analysis time for separation was less than 20 min without losing any resolution. In the variable, importance in projection plot of orthogonal projection to latent structure‐discriminant analysis, a total of 72 ions of interest (37 ions in positive mode, 38 ions in negative mode and three ions in both mode) were extracted or tentatively characterized based on their retention times, exact mass measurement for each molecular ion and subsequent fragment ions. In summary, the methodology proposed in this study could be valuable for the structural characterization and identification of the multiple constituents in the traditional Chinese medicine formula SW.