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91.
Herbal products produced from multiple plants have special characteristics in the clinical practice of traditional Chinese medicine. These traits provide the opportunity for fraudulent merchants to mix other herbal products similar in appearance into authentic herbal medicine. Shihu is a tonic herbal medicine from the Dendrobium plants with complex botanical origins. In this context, 11 Dendrobium plants including 109 individuals from China were collected for authentication work. Nine species have been described as herbal medicines in the literature while D. hookerianum and D. xichouense are not reported to have medicinal benefits. A key feature of this study was that multiple recognition approaches, based on near-infrared and ultraviolet–visible spectra as well as their combination, were compared to investigate their classification performance. Intuitively, score plots using principal component analysis and hierarchical cluster diagrams were used to evaluate the genetic relationships among these species. Compared with support vector machine discrimination analysis and k-nearest neighbor models, the partial least square discrimination analysis model combined with low-level data fusion provided excellent performance for authentication and was the most robust model with 100% accuracy rates for the training and prediction sets. The results indicated that near-infrared and ultraviolet–visible spectra and their fusion dataset combined with supervised recognition analysis are effective and therefore recommended for the authentication of genuine and sham of herbal Shihu species. 相似文献
92.
Isoquinoline alkaloids (papaverine, noscapine, berberine, emetine, and quinine) were determined in medicinal plants and herbs used in Traditional Chinese Medicine and Ayurveda by liquid chromatography with tandem mass spectrometry detection (LC-MS/MS). The analyzed alkaloids were separated at gradient conditions using methanol and 2% acetic acid within 12?min. The validated method was successfully applied for 17 herbal samples: Ashwagandha, Astragalus membranaceus, Emblica officinalis, Mucuna pruriens, Pueraria lobata, Ocimum sanctum, Rehmannia glutinosa, Schisandra sinensis, Terminalia arjuna, Terminalia chebula, and dietary supplements. The highest concentration of studied alkaloids was observed for berberine in Puearia lobata (6.68?±?0.62?mg 100?g?1 d.m.), while the lowest value was obtained for noscapine in a dietary supplement containing Terminalia arjuna (0.09?±?0.01?mg 100?g?1 d.m.). Principal component analysis, cluster analysis, and one-way ANOVA tests were also performed. The results indicate the need to control plant materials and dietary supplements in terms of the content of alkaloids and toxic components. 相似文献
93.
Luteolin, a flavonoid, is reported to occur widely in many medicinal plants. It has been shown to have important biological activities. We report sensitive HPTLC method for the quantification of luteolin from plant material. The method was validated for precision, repeatability and accuracy. The method was found to be precise with RSDs for intraday in the range of 0.77–1.29% and inter–day in the range of 1.02–2.08%. Instrumental precision and repeatability of the method were found to be 0.39 and 0.57 (%CV). Accuracy of the method was checked by recovery study conducted at two different levels and the average percentage recovery was found to be 100.92%. The method was used for quantification of luteolin in three important herbal drugs viz. fruit of Cuminum cyminum, whole plant of Bacopa monnieri, flower of Achillea millefolium. The proposed HPTLC method for the quantification of luteolin was found to be simple, precise, specific, sensitive and accurate and can be used for quality control of raw materials.Revised: 1 October 2003 and 18 February 2004 相似文献
94.
本文研究了用4N盐酸煮沸提取植株中的K、Na、Ca、Mg、P、Cu、Zn、Fe、Mn、Sr、Ba和B的实验条件。浸提液用ICP-AES测定,获得了满意的结果。方法简单、操作简便、安全。与硝酸-高氯酸湿消化法进行了对照,结果非常一致,除硼外十一种元素都不存在显著差异。并测定了国家级标准甘兰物质GBW 08504,其结果与标准值相符。 相似文献
95.
微波消解技术在农业样品分析中的应用 总被引:7,自引:0,他引:7
利用光纤压力自控密闭微波消解系统对土壤和植株样品中重金属元素测定的影响进行了研究,确立了样品消解试剂、微波消解每件及样品预处理方法。结果表明,该方法与常压湿法消解相比,具有样品消解时间短、消解试剂用量少、样品污染小等特点,是准确可靠的土壤及植株样品中重金属元素检测样品消解处理方法。 相似文献
96.
An intermediate expressing vector carrying the tobacco mosaic virus (TMV, Chinese common strain) coat protein (CP) gene was constructed by recombinant DNA techniques. The TMV-CP gene was transferred into the tobacco genome via Ti plasmid and a large number of regenerated plants, including both systemic and local lesion hosts for TMV, were obtained. Southern blot analysis revealed that 1-5 copies of the CP gene were integrated into the tobacco genome. RNA and protein analysis demonstrated that the TMV-CP gene was correctly expressed in the transgenic plants. The abundance of TMV-CP mRNA in total leaf RNA accounted for 0.005-0.01%, while the amount of coat proteins reached 0.05-0.2% of the total leaf soluble proteins. Virus challenge experiments showed that the symptom development of virus infection was markedly delayed and the replication as well as the spread of the virus was significantly inhibited in the transgenic plants expressing the TMV-CP gene. Three of these plants were completely protected afte 相似文献
97.
P. Bednar A.V. Tomassi C. Presutti M. Pavlikova K. Lemr S. Fanali 《Chromatographia》2003,58(5-6):283-287
Summary A method based on micellar electrokinetic chromatography has been developed for the simultaneous separation of six anthocyanins (malvidin-3,5-diglucoside, malvidin-3-glucoside, malvidin-3-galactoside, pelargonidin-3-glucoside, cyanidin-3,5-diglucoside, cyanidin-3-galactoside). Optimum selectivity was achieved in the buffer 30 mM phosphate + 400 mM borate-TRIS, pH=7.0 supported with 50 mM sodium dodecylsulphate. High content of borate was essential mainly for the separation of diastereomeric pair malvidin-3-glucoside-malvidin-3-galactoside. The calibration dependencies exhibit good linearity in the ranges of concentration 10–100 g mL–1 for diglycosylated and 25–100 g mL–1 for monoglycosylated derivatives (R2 = 0.9711–0.9989). The optimized method was applied to a sample of wine grape skin extract. Malvidin-3-glucoside was identified as main anthocyanin colorant in this sample. 相似文献
98.
《Analytical letters》2012,45(9):1640-1647
Abstract A method for isotopic determination of silicon by mass spectrometry in plants and soils labeled with 30Si is reported. The development of this method is for use with studies involving the physiological process of absorption, transport, and redistribution of Si in the soil-plant system by use of the stable isotope 30Si as a tracer. The procedure leads to SiF4 formation, and the isotopic determination of Si was based on the measurements of the 28SiF3 +, 29SiF3 +, and 30SiF3 + signals. Relative standard deviation of 30Si abundance measurements (n = 6) were lower than 0.1%, and the detection limit was 0.5 mg Si (dry mass). 相似文献
99.
采用自行设计的多用途荧光比色皿,建立了一种秋茄(Kandelia obovata,Ko),桐花树(Aegiceras comiculatum,Ac)和白骨壤(Avicennia marina,Am)叶片表面菲(Phenanthrene,Phen)简便的原位测定方法,本方法测定Ko,Ac和Am表面Phen的线性范围分别为6.5 ~ 1200 ng/spot,18.5~600 ng/spot和3.2~700 ng/spot,检出限分别为0.6,0.7和1.3 ng/spot,加标回收率分别为92.4%~101.0%、94.8%~108.2%和93.8%~103.6%,相对标准偏差小于6.5%.本方法的检出限和相对标准偏差均优于固体表面光纤荧光法(Solid surface optical fiber fluorimetry,SSF),线性范围与SSF法处于同一数量级.本方法与SSF法测得的红树叶片表面Phen的浓度并无显著差异(p>0.05),但本方法极大地简化了操作,提高了重现性. 相似文献
100.
Plausible effect of clustering of undercooled
liquid water (pentamer configuration, icosahedra formation) is discussed showing
water continuous but non-periodic patterns and its impact to the either formation
of ice-crystals or ice-glass, particularly when making contact with plants.
These processes are viable for the cryogenic storage of biological germplasm
and subject for thermoanalytical studies aimed to the determination of glass
transition temperatures. 相似文献