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21.
Somyote Sutthivaiyakit Narissara Na NakornWolfgang Kraus Pakawadee Sutthivaiyakit 《Tetrahedron》2003,59(50):9991-9995
An unusual 29-nor-3,4-seco-friedelan-4(23),20(30)-dien-3-oic acid and a new 5-hydroxy-6,9-epoxyguaiane have been isolated along with other rare terpenes and lignans from Phyllanthus oxyphyllus roots. Their structures were elucidated from spectroscopic data. The radical scavenging properties of some of these compounds were evaluated. seco-Isolariciresinol showed strong antioxidant activity (IC50 0.017±0.001 mM). 相似文献
22.
Chun‐Bin Yang Fan Zhang Mei‐Cai Deng Guang‐Yun He Jian‐Min Yue Run‐Hua Lu 《中国化学会会志》2007,54(6):1615-1618
A new ellagitannin along with eight known compounds has been isolated from the ethanol extract of the fruit of Phyllanthus emblica L. The chemical structure of the new compound was established as Phyllanthunin (1) by HR‐ESI‐MS, 1D and 2D NMR spectroscopic analysis. 相似文献
23.
Gallic acid and ellagic acid are two widely occurring phenolic compounds of plant origin, to which many biological activities including anticancer and antiviral activity have been attributed. A simple HPTLC method has been developed for the simultaneous quantification of gallic acid and ellagic acid. The method was validated for precision, repeatability, and accuracy. Instrumental precision was found to be 0.083 and 0.78, and the repeatability of the method was found to be 1.07 and 1.50 (% CV) for gallic acid and ellagic acid, respectively. The accuracy of the method was checked by a recovery study conducted at two different levels and the average percentage recovery was found to be 101.02% for gallic acid and 102.42% for ellagic acid. The above method was used for the quantification of gallic acid and ellagic acid content in seeds of Abrus precatorius Linn., whole plant of Phyllanthus maderaspatensis Linn., and flowers of Nymphaea alba Linn. The proposed HPTLC method for the simultaneous quantification of gallic acid and ellagic acid was found to be simple, precise, specific, sensitive, and accurate and can be used for routine quality control of herbal raw materials and for the quantification of these compounds in plant materials. 相似文献
24.
Renata Colombo Andrea N. de L. Batista Helder L. Teles Geraldo H. Silva Giovani C. C. Bomfim Rosilene C. R. Burgos Alberto J. Cavalheiro Vanderlan da Silva Bolzani Dulce Helena S. Silva Clícia R. Pelícia Fabiana M. Guimarães Maria Célia H. Heimberg 《Biomedical chromatography : BMC》2009,23(6):573-580
Phyllanthus niruri L., commonly known in Brazil as ‘quebra‐pedra’, has long been used in the treatment of diverse diseases and especially urolithiasis. The therapeutic effects of P. niruri are attributed to various compounds present in the plant, including the hydrolysable tannin corilagin. In the present study, high‐performance liquid chromatography (HPLC‐/PAD) profiles of leaves and commercial extracts of P. niruri were examined and three compounds, found to be present in all of the samples studied, were isolated by open column chromatography over C18 silica gel followed by preparative HPLC. These compounds were identified by nuclear magnetic resonance as corilagin, rutin and ethyl 3,4,5‐trihydroxybenzoate. Corilagin, which has been proposed as a phytochemical marker for P. niruri, was employed as an external standard in the development and validation of a rapid and efficient qualitative and quantitative HPLC assay for the analyte. The method may be applied in the standardization of herbs and phytomedicines commercialized in Brazil as quebra‐pedra. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献