Pseudotargeted screening and determination of constituents in Qishen granule based on compound biosynthetic correlation using UHPLC coupled with high‐resolution MS

Detection and determination of many known/unknown compounds in traditional Chinese medicines have always been challenging. To comprehensively identify compounds in Qishen granule, which is a widely prescribed herbal formula for treating chronic heart failure, a pseudotargeted screening method was proposed based on compound biosynthetic correlation using ultra high‐performance liquid chromatography coupled with high‐resolution mass spectrometry. Firstly, all possible compounds of Qishen granule were classified into nine types according to their core skeletons, and potential analogue molecular formulas were predicted according to core compound‐related biosynthetic correlations, such as methylation, hydroxylation, and glucosidation. Secondly, nine pseudocompound databases consisting of core compounds, deduced biosynthetic correlations, and predicted analogue molecular formulas were established. Then, compounds of interest were directly located by pseudotargeted screening of high resolution mass spectrometry data and further verified by target tandem mass spectrometry. As a result, 213 constituents were identified and 21 of them were determined as potential new compounds. This demonstrated that pseudotargeted screening based on compound biosynthetic correlations significantly facilitated the processing of extremely large information data and improved the efficiency of compound identification. This research provided essential data for exploration of effective substances in Qishen granule and enriched the methodology for comprehensive characterization of constituents in complex traditional Chinese medicines.     

Comprehensive separation of iridoid glycosides and triterpenoid saponins from Dipsacus asper with salt‐containing solvent by high‐speed countercurrent chromatography coupled with recycling mode

The roots of Dipsacus asper Wall as a commonly used traditional Chinese medicine are used for tonifying liver and kidney and strengthening bones and muscles. However, an effective separation strategy for comprehensive and rapid separation of the main active compounds from the roots of D. asper is nonexistent. This investigation provided an effective separation method based on AB‐8 macroporous resin column chromatography using different ratios of ethanol in water and two different modes of high‐speed countercurrent chromatography with salt‐containing solvent system for rapid enrichment and separation from the roots of D. asper. The macroporous resin column chromatography was performed on AB‐8 resin using ethanol in water ratios of 10, 30, 40, 50, and 80% as the optimized enrichment conditions for iridoid glycosides and triterpenoid saponins with different polarities. For high‐speed countercurrent chromatography separation, the conventional and recycling modes were combined together to develop a strategy for 12 compounds ( 1 – 12 ) from the enriched parts of 30, 40, and 80% ethanol, including six high‐polarity iridoid glycosides ( 1 – 6 ) using inorganic salt‐containing solvent system and six triterpenoid saponins ( 7 – 12 ). Recycling high‐speed countercurrent chromatography separation was successfully applied to separate two isomers ( 9 and 10 ) after 11 cycles.     

Magnetic molecularly imprinted specific solid‐phase extraction for determination of dihydroquercetin from Larix griffithiana using HPLC

The naturally occurring quercetin flavonoid, dihydroquercetin, is widely distributed in plant tissues and has a variety of biological activities. Herein, a magnetic molecularly imprinted solid‐phase extraction was tailor made for selective determination of dihydroquercetin in Larix griffithiana using high‐performance liquid chromatography. Amino‐functionalized core‐shell magnetic nanoparticles were prepared and characterized using scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and infrared spectroscopy. The polymer had an average diameter of 250 ± 2.56 nm and exhibited good stability and adsorption for template molecule, which is enriched by hydrogen bonding interaction. Multiple factors for extraction, including loading, washing, elution solvents, and extraction time, were optimized. The limit of detection was 1.23 μg/g. The precision determined at various concentration of dihydroquercetin was less than 4% and the mean recovery was between 74.64 and 101.80%. It has therefore been shown that this protocol can be used as an alternative extraction to quantify dihydroquercetin in L. griffithiana and purify quercetin flavonoid from other complex matrices.     

Rapid detection of pesticide residues in Chinese herbal medicines by molecularly imprinted membrane electrospray ionization mass spectrometry

Chinese herbal medicines(CHMs) play an increasingly important role in the field of medicine and affects public health in the world.Although more and more strict has been employed to ensure the quality and safety of CHMs,pesticide residues in CHMs remain a serious issue and are the bottleneck for the global development of CHMs.In this work,we applied molecularly imprinted membrane electrospray mass spectrometry(MIM-ESI MS) for rapid detecting 4 classes of pesticide residues in CHMs,including organophosphorus(OPP),carbamates,pyrethroids and neonicotinoids in CHMs.Compared with our previous ambient ionization method MESI,MIM-ESI is capable of achieving a ～50-fold increase in the detection limit of conventional analytical methods owing to the specificity recognition and unique enrichment of MIM.The optimal experimental conditions were determined,and the method was further validated for its sensitivity and specificity.Our data showed that MIM-ESI MS is applicable for the direct quantitation of pesticide residues in CHMs.This detection technology may help to ensure the quality of CHMs in the future.     

Differentiating parts of Cinnamomum cassia using LC‐qTOF‐MS in conjunction with principal component analysis

Cinnamon bark (Rou Gui in Chinese), cinnamon twig (Gui Zhi) and shaved cinnamon bark (Gui Sin) have been widely used as spices and in traditional Chinese medicine since ancient times. On‐going issues related to quality and authenticity necessitate the development of analytical methods capable of providing an objective evaluation of samples. In this study, chemical fingerprints of cinnamon bark, cinnamon twigs and shaved cinnamon bark were established using liquid chromatography quadruple time‐of‐flight mass spectrometry in conjunction with principal component analysis (PCA). From 125 samples of cinnamon, we identified the following eight compounds and their the detection ratios: coumarin, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, 2‐hydroxycinnamaldehyde, 2‐hydroxycinnamic acid, 2‐methoxycinnamaldehyde and 4‐methoxycinnamaldehyde. Of these, 4‐methoxycinnamaldehyde presented the largest variations in detection ratio, making up 64.0, 97.4 and 50.0% in cinnamon bark, cinnamon twig, and shaved cinnamon bark, respectively. The quantities of cinnamyl alcohol, coumarin and cinnamaldehyde also varied between the three parts of the plant. Chemical fingerprints of the three cinnamon samples were established using principal component analysis, the results of which indicate that cinnamon bark and shaved cinnamon bark could be easily differentiated, despite a marked similarity in outward appearance. Cinnamon twig was also shown to depart from the other clusters. The proposed method provides a fast and efficient means of identifying cinnamon herbs for quality control purposes. Copyright © 2016 John Wiley & Sons, Ltd.     

The effect of resistant starches on fat oxidation in healthy adults as measured by a 13CO2-breath test

A resistant starch (RS) mixture (MIX) consisting of fibre of potatoes (FP) and wrinkled pea starch (WPS), and high amylose maize starch (HAMS) were supplemented in adults to evaluate their effects on fat oxidation by means of a ¹³CO₂-breath test. Sixteen subjects received a regular diet either without or with the supplementation of MIX and HAMS in randomised order. After administration of a [U-¹³C]algal lipid mixture, exhaled air was collected over 14?h in 0.5- and 1-h intervals. The ¹³C abundances were measured by nondispersive infrared spectroscopy. In comparison to the dry run (DR), supplementation with MIX and with HAMS increased the cumulative percentage dose recovery: (DR: 16.7?%, MIX: 16.9?%, HAMS: 18.0?%), but without statistical significance. The colonic degradation of MIX and HAMS to short-chain fatty acids tends to lower the formation of carbohydrate-derived acetyl-CoA and contributes to a postprandial lipid oxidation increase by using fat-derived acetyl-CoA as a compensatory fuel source.     

中国医学物理学的过去、现在与未来

医学物理（medical physics，MP）是把物理学的原理和方法应用于人类疾病的预防、诊断、治疗和保健的一门交叉学科，是物理学与医学实践相结合的一门独立的分支学科．它是研究人类疾病诊、治过程中的物理现象，并用物理方法表达这种现象．医学物理包括放射肿瘤物理（rsdiation oncdogy physics，ROP）、医学影像物理（medical imaong physics，MIP）、核医学物理（nuclear medicine physics，NMP），其他非电离辐射如核磁、超声、微波、射频、激光等物理因子在医学中的应用，和保健物理（heath physics，HP）等分支内容．医学物理学和生物医学工程学（biomedical engineefing，BME）是一对栾生的兄弟学科，分别从物理学的角度（前者）和工程学的角度（后者）研究人类疾病诊断、治疗及健康保健过程中的生命现象和采取相应的物理措施和工程手段。医学物理学与物理医学（physical medicine，PM）是完全两个不同的概念，前者是物理学的分支，后者是医学的分支．自上世纪60年代以来，中国医学物理学有了很大的进展，推动了中国现代放射肿瘤学、核医学和医学影像学的发展；成立了自己的学术组织，并成为国际医学物理组织（IOMP）的成员国组织．随着中国逐步奔入小康社会，为适应人民大众对健康的需求和现代化医院发展的需要，中国医学物理应该加快发展．     

中药柴胡中K、Ca、Zn、Fe和Mn含量测定及清除自由基机制分析

研究了柴胡中金属元素的作用为治疗呼吸系统疾病提供依据.选取柴胡粉碎、干燥至恒重,采用HNO3-HClO4湿法消化,用原子吸收分光光度计测定宏量元素钙、钾和微量元素铁、锰、锌的含量.测定结果表明,柴胡中含有丰富的金属元素.用原子吸收分光光度法测定中草药中金属元素含量,方便迅速.结果准确,测定结果为临床上合理利用柴胡清除自由基、预防和治疗呼吸系统疾病提供科学依据,也为大力开发、利用中药柴胡提供了有用的数据.     

便携式近红外漫反射中药质量监控仪的研制

介绍了便携式近红外漫反射中药质量监控仪的设计思想、基本结构、测试条件和使用方法。该光谱仪具有体积小、重量轻、成本低等特点,现场监控中药质量是非常便利的。     

我国中药出口贸易发展现状分析及对策研究

对中药出口贸易的发展现状进行了分析,从机遇与挑战方面阐述了其发展趋势,对中药实现现代化,推动国际化,知识产权保护以及如何消除贸易壁垒等方面提出了对策及建议。由于国家政府各项政策的倾斜,将进一步加快我国中药产业的发展,从现代化走向国际化。