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The polyphenolic compound 1-O-galloyl-3,6-hexahydroxybiphenyl-D-galactopyranoside (pusilagin) was isolated from the aerial part. The tannin structure was established using acid hydrolysis and IR, PMR, and 13C NMR spectral methods.  相似文献   
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In order to continue our previous studies concerning Geranium pyrenaicum Burm. (Geraniaceae), we have performed spectrophotometric determinations and a HPLC study of some polyphenols. We have analyzed the dried Geranii pyrenaici herba (harvested from Cluj-Napoca, district of Cluj, Romania). We have established the content in flavonoids (0.316%), phenolic acids (0.099%), tannins (5.295%), and anthocyanins (12.030 mg/100 g vegetal product). We have identified and measured by HPLC the following compounds: hyperoside (21.61 μg/100 mg), ellagic acid (1810.44 μg/100 mg), isoquercitrine (11.197 μg/100 mg), and caftaric acid (76.83 μg/100 mg). We have also analyzed by HPLC a hydrolyzed sample of the same drug in which we have identified and measured: ellagic acid (4139.33 μg/100 mg), quercetol (29.65 μg/100 mg), kaempherol (41.48 μg/100 mg), and caftaric acid (20.721 μg/100 mg). __________ Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 322–324, July–August, 2005.  相似文献   
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Over the last years, nanotechnology has contributed to the development of new botanical insecticides formulations based on essential oils (EO), which are safe for the human health and the environment. Nanoemulsions (NEs) can enhance the bioactivity of the EO to prevent the premature volatility and degradation of the active ingredients. In our work, geranium EO (Geranium maculatum L.) was used to develop micro and nanoemulsions adding Tween 80 as surfactant. For NEs formulation, ultrasound was applied and the physicochemical and ultrasound parameters were optimized: oil: surfactant ratio = 1:2, ultrasound power = 65 W, sonication time = 2 min, cycles = 30 on/20 off and ultrasonic probe distance = 3.7 cm. The NEs obtained had 13.58 nm and polydisperse index (PDI) values of 0.069. They were stored at 25 °C and were stable for 60 days.The present study also demonstrated the potential of NEs to enhance the toxicity of geranium EO against larvae of Culex pipiens pipiens (EO LC50 = 80.97 ppm, NEs LC50 = 48.27 ppm) and Plodia interpunctella (EO + β-cypermethrin LD50 = 0.16 μg larvae−1, NEs + β-cypermethrin LD50 = 0.07 μg larvae−1). Overall, our findings pointed out that NEs can increase twofold the insecticidal efficacy of EO, and thus, they can be considered further for the development of botanical insecticides.  相似文献   
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Traditional Chinese Medicine is generally used as a decoction to guard health. Many active ingredients in the decoction are chemical ingredients that are not usually paid attention to in phytochemical research, such as polysaccharides, etc. Based on research interest in Chinese herbal decoction, crude polysaccharides from G. wilfordii (GCP) were purified to obtain two relatively homogeneous polysaccharides, a neutral polysaccharide (GNP), and an acid polysaccharide (GAP) by various chromatographic separation methods, which were initially characterized by GC-MS, NMR, IR, and methylation analysis. Studies on the hepatoprotective activity of GCP in vivo showed that GCP might be a potential agent for the prevention and treatment of acute liver injury by inhibiting the secretion levels of ALT, AST, IL-6, IL-1β, TNF-α, and MDA expression levels, increasing SOD, and the GSH-Px activity value. Further, in vitro assays, GNP and GAP, decrease the inflammatory response by inhibiting the secretion of IL-6 and TNF-α, involved in the STAT1/T-bet signaling pathway.  相似文献   
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以没食子酸含量和出膏率的综合评分为指标,以溶剂用量、提取时间和提取次数为考察因素,采用正交试验优选老鹳草中没食子酸的提取工艺。结果表明,最佳提取工艺为8倍量水、回流提取3次,每次60m in。该工艺稳定可行,可作为老鹳草中没食子酸的提取方法。  相似文献   
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老鹳草中药材红外光谱的分析与鉴定   总被引:1,自引:0,他引:1  
采用红外光谱、二阶导数光谱和二维相关红外光谱对来自黑龙江、吉林、辽宁三省的老鹳草中药材进行了分析。不同产地的老鹳草的红外光谱都具有1 730和1 337 cm-1等表征鞣质类成分的特征吸收峰和1 618和1 318 cm-1波数表征草酸钙的特征峰。其中还发现在1 370 cm-1的C—H弯曲振动区和1 230 cm-1的C—O伸缩振动区三产地老鹳草具有一定的差异性。在高分辨的二阶导数谱中, 1 509,1 204,764和763 cm-1附近的表征鞣质类成分的吸收峰更明显,三产地老鹳草在CO羰基伸缩振动区表征了脂肪类化合物的不同;尤其是在二维相关光谱上,各自的自动峰具有显著的差异性,黑龙江的老鹳草出现了7个自动峰,其中1 621 cm-1处自动峰最强;而在吉林和辽宁产地的老鹳草中同样出现了4个自动峰,前者1 580 cm-1处的自动峰最强,后者在1 649 cm-1处自动峰最强。该方法直观、简单、方便、快速,可以作为鉴别和鉴定同种不同产地老鹤草的一种新方法。  相似文献   
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