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81.
Yueting Li Jie Liu Rubin Su Qian Li Yijun Chen Jiao Yang Shujun Zhao Zhixin Jia Hongbin Xiao 《Journal of separation science》2020,43(6):1032-1042
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. 相似文献
82.
Jinqian Yu Jinqiang Zhang Xiaowei Sun Chenghong Xiao Xiao Wang Tao Zhou 《Journal of separation science》2020,43(7):1265-1274
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. 相似文献
83.
84.
Chenggang Cai Guoli Chang Miaomiao Zhao Pinggu Wu Zhengyan Hu Dingguo Jiang 《Molecules (Basel, Switzerland)》2022,27(6)
The four polycyclic aromatic hydrocarbon markers (PAH4) of benzo[a]anthracene (BaA), chrysene (Chr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP) are indicators showing polycyclic aromatic hydrocarbon (PAH) contamination levels in Chinese medicine raw materials (CMRMs), extracts and health food products; Samples of herbal medicine, herbal extracts, and food supplements were extracted with n-hexane, then cleaned up sequentially on Florisil and EUPAH solid-phase extraction (SPE) columns. A gas chromatography–mass spectrometry method for the determination of four polycyclic aromatic hydrocarbon markers in Chinese medicine raw material, extracts, and health food products was established; In spiked-recovery experiments, the average recovery was about 78.6–107.6% with a precision of 2.3–10.5%. The limit of quantification (LOQ) and limit of detection (LOD) of the PAH4 markers in this method were 2.0 μg/kg and 0.7 μg/kg, respectively. When the developed method was utilized to determine PAH4 contents in 12 locally available health food products, 3 samples contained over 10.0 μg/kg BaP, and 5 samples contained over 50.0 μg/kg PAH4. The European Union (EU) limits for BaP and PAH4 are 10 and 50.0 μg/kg, respectively; therefore, more attention must be drawn to the exposure risk of BaP and PAH4 in CMRMs, their extracts, and health food products. According to the risk assessment based on the Margin of Exposure (MOE) method, it is recognized that the products mentioned in this study pose a low risk. 相似文献
85.
阵列相关系数比对法在中药鉴别中的应用研究 总被引:2,自引:0,他引:2
中药材红外光谱具有“指纹”性,通过对红外特征吸收谱图的比对可达到区分和鉴别药材的目的。该研究用Visual Basic 6.0设计了中药材红外光谱阵列相关系数比对软件,建立了300多种中药药材的红外光谱数据库,将未知药材的红外光谱与数据库中药材的红外光谱进行比对,它能依11个波段两光谱相关系数的大小自动找到与库中最相似的光谱的药材,从而达到鉴别未知药材的目的。研究结果表明:在光谱数据库所包含的药材范围内,指定阵列相关系数的阈值,抓住特征波段光谱的比对,可避开CO2和H2O等外界因素对谱图的干扰,使比对结果准确可靠。该法有望成为中药材快速鉴别的一种常规手段。 相似文献
86.
氢化物发生-原子荧光法测定中药中痕量砷 总被引:1,自引:0,他引:1
应用AFS-2202a型双道原子荧光分光光度计,采用高压溶样的消解方式,在选定的仪器工作条件下,建立了氢化物发生-原子荧光测定中药中痕量砷的测定方法。同时,研究了硼氢化钾浓度,光电管负高压,灯电流,载气流量,屏蔽气流量等因素对测定结果的影响。在选定实验条件下,以工作曲线法测定了三种中药样品中痕量砷含量,国家标准物质桃叶(GBW08501)验证结果与推荐值一致。砷的工作曲线在0~80.0 μg·L-1范围内线性良好,线性回归方程为If=8.99×c-1.16, 相关系数为0.999 9,检出限为0.069 μg·L-1。 相似文献
87.
Jinhao Zou Yan Li Xiaojun Su Feng Wang Qingming Li Huiping Xia 《Molecules (Basel, Switzerland)》2022,27(7)
In order to explore the processing and application potential of Chinese yam starch, nine kinds of Chinese yam starch (GY11, GY5, GY2, GXPY, LCY, SFY, MPY, SYPY, ASY) from South China were collected and characterized. The chemical composition, rheological properties, thermal properties, and in vitro starch digestion were compared, and the correlation between the structure and processing properties of these yam starches was analyzed using Pearson correlation. The results show that GY2 had the highest amylose content of 28.70%. All the yam starches were similarly elliptical, and all the yam starch gels showed pseudoplastic behavior. Yam starches showed similar pasting temperatures and resistant starch content, but SYPY showed the largest particle size (28.4 μm), SFY showed the highest setback (2712.33 cp), and LCY showed the highest peak viscosity (6145.67 cp) and breakdown (2672.33 cp). In addition, these yam starches also showed different crystal types (A-type, B-type, C-type), relative crystallinity (26.54–31.48%), the ratios of 1045/1022 cm−1 (0.836–1.213), pasting properties, and rheological properties, so the yam starches have different application potentials. The rheological and pasting properties were related to the structural properties of starch, such as DI, Mw, and particle size, and were also closely related to the thermodynamic properties. The appropriate processing methods and purposes of the processed products of these yam starches can be selected according to their characteristics. 相似文献
88.
89.
自1981年创刊以来,《光学学报》以发表国内优秀光学科研成果为己任,为我国光学科技人员提供了高水平、活跃的学术交流平台.《光学学报》经历了近40年的洗礼,见证了国内一代代优秀光学科研人员的成长.本文首先回顾了《光学学报》从创刊到转企、集群化发展,再到数字化出版的变革之路;其次,统计了《光学学报》历年来的出版数据、数据库... 相似文献
90.
Kaizhe Liu Meifang Gao Haozhao Jiang Shuying Ou Xiaopeng Li Rui He Yamin Li Houcheng Liu 《Molecules (Basel, Switzerland)》2022,27(3)
We explored the effects of different light intensities and photoperiods on the growth, nutritional quality and antioxidant properties of two Brassicaceae microgreens (cabbage Brassica oleracea L. and Chinese kale Brassica alboglabra Bailey). There were two experiments: (1) four photosynthetic photon flux densities (PPFD) of 30, 50, 70 or 90 μmoL·m−2·s−1 with red:blue:green = 1:1:1 light-emitting diodes (LEDs); (2) five photoperiods of 12, 14, 16, 18 or 20 h·d−1. With the increase of light intensity, the hypocotyl length of cabbage and Chinese kale microgreens shortened. PPFD of 90 μmol·m−2·s−1 was beneficial to improve the nutritional quality of cabbage microgreens, which had higher contents of chlorophyll, carotenoids, soluble sugar, soluble protein and vitamin C, as well as increased antioxidant capacity. The optimal PPFD for Chinese kale microgreens was 70 μmol·m−2·s−1. Increasing light intensity could increase the antioxidant capacity of cabbage and Chinese kale microgreens, while not significantly affecting glucosinolate (GS) content. The dry and fresh weight of cabbage and Chinese kale microgreens were maximized with a 14-h·d−1 photoperiod. The chlorophyll, carotenoid and soluble protein content in cabbage and Chinese kale microgreens were highest for a 16-h·d−1 photoperiod. The lowest total GS content was found in cabbage microgreens under a 12-h·d−1 photoperiod and in Chinese kale microgreens under 16-h·d−1 photoperiod. In conclusion, the photoperiod of 14~16 h·d−1, and 90 μmol·m−2·s−1 and 70 μmol·m−2·s−1 PPFD for cabbage and Chinese kale microgreens, respectively, were optimal for cultivation. 相似文献