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31.
32.
将超声辅助离子液体/阴离子表面活性剂双水相萃取和高效液相色谱法相结合,建立一种简单、绿色、高效的分析方法用于检测虎杖中的虎杖苷和白藜芦醇。本研究以水溶性离子液体为萃取剂,以阴离子表面活性剂为成相盐,在超声的辅助作用下,目标分析物被萃取于离子液体中。实验结果表明,最佳提取条件为:以400μL 1-丁基-3-甲基咪唑四氟硼酸盐为萃取剂,0.16 g十二烷基苯磺酸钠为成相盐,样品溶液pH 7.0,超声时间20 min,超声功率160 W。各化合物在线性范围内都具有良好的线性关系(r0.9995),日内和日间精密度分别低于3.27%和6.31%,检出限和定量限分别为2.8~12.3和9.4~41.1 ng/mL,样品加标回收率在86.88~94.13%之间。本研究采用离子液体代替传统的有机溶剂作为萃取剂,集提取、分离和纯化于一体,具有操作简单、溶剂用量少、提取时间短等优点,可广泛应用于中药活性成分的提取与分析。 相似文献
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二苯乙烯苷特性及DPPH自由基清除活性 总被引:1,自引:0,他引:1
讨论何首乌中二苯乙烯苷晶体的理化性质及清除DPPH自由基活性.从何首乌中分离结晶得到二苯乙烯苷晶体,并运用液-质(LC-MS)、核磁(NMR)、X-射线衍射、差示扫描量热分析(DSC)、热重分析(TGA)等技术分析晶体性质及稳定性,对照Vc、BHT、白藜芦醇测定了其清除DPPH自由基的活性.试验表明二苯乙烯苷晶体不存在同质多晶现象,仅有一种针状晶体存在形式,且不含结晶水,熔点为151.33℃.且其晶体具有良好的稳定性.其清除自由基活性依次为:Vc IC505.38μg/mL,BHT IC506.20μg/m l,二苯乙烯苷IC508.06μg/mL,白藜芦醇IC509.21μg/mL.从何首乌提取物中可以通过结晶得到单一针状、稳定的二苯乙烯苷晶体,且该晶体具有良好的清除DPPH自由基功能. 相似文献
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The root exudates fromPolygonum sachalinense in a recirculating system significantly inhibited lettuce seedling growth. The rhizomes and roots ofP. sachalinense were extracted with 80% acetone. Bioassay of the neutral-acidic fraction on the TLC agar plate showed the inhibitory activity
corresponded to the two yellow pigment bands. Two orange needles were isolated and identified as anthraquinone compounds:
emodin and physcion. Both compounds exhibited inhibitory activities against the seedling growth of several testing plant species.
Glucosides were isolated fromP. sachalinense and were identified as emodin-1-O-β-D-glucoside and physcion-1-O-β-D-glucoside, respectively. On plant growth bioassay, these glucosides showed no phytotoxic activity against lettuce seedlings.
The concentrations of emodin, physcion, and their glucosides from rhizome with roots, aerial parts, fallen leaves, and soil
were determined. The rhizome with roots and fallen leaves contained emodin and physcion at relatively high concentrations.
Emodin also occurs in the soil of this plant community with effective concentrations in the fall. The results indicate that
these anthraquinones are responsible for the observed interference and are potent allelopathic substances. 相似文献
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Qader SW Abdulla MA Chua LS Sirat HM Hamdan S 《International journal of molecular sciences》2012,13(2):1481-1496
The leaves of Polygonum minus were fractionated using an eluting solvent to evaluate the pharmacological mechanisms underlying the anti-ulcerogenic activity of P. minus. Different P. minus fractions were obtained and evaluated for their ulcer preventing capabilities using the ethanol induction method. In this study, Sprague Dawley rats weighing 150-200 g were used. Different parameters were estimated to identify the active fraction underlying the mechanism of the gastroprotective action of P. minus: the gastric mucus barrier, as well as superoxide dismutase, total hexosamine, and prostaglandin synthesis. Amongst the five fractions from the ethanolic extract of P. minus, the ethyl acetate:methanol 1:1 v/v fraction (F2) significantly (p < 0.005) exhibited better inhibition of ulcer lesions in a dose-dependent manner. In addition, rats pre-treated with F2 showed a significant elevation in superoxide dismutase (SOD), hexosamine and PGE2 levels in the stomach wall mucosa in a dose-dependent matter. Based on these results, the ethyl acetate:methanol 1:1 v/v fraction was considered to be the best fraction for mucous protection in the ethanol induction model. The mechanisms underlying this protection were attributed to the synthesis of antioxidants and PGE2. 相似文献
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白藜芦醇具有多种生物学活性,具有很高的应用价值,白藜芦醇的前体物质白藜芦醇苷在虎杖中含量较高,可通过微生物转化成白藜芦醇。论文采用添加有白藜芦醇苷的固体培养基,从虎杖内筛选能将白藜芦醇苷转化成白藜芦醇的内生菌,然后对筛选到的菌种进行鉴定。通过菌种形态学、显微镜观察和18srDNA序列分析等方法,鉴定结果显示该菌种为卡门培尔青霉(Penicilliumcamemberti)。 相似文献
40.
本文建立了虎杖中五种活性成分:虎杖苷、白藜芦醇、大黄素-8-O-β-D-葡萄糖苷、大黄素、大黄素甲醚的高效液相色谱分析方法。色谱柱为Agilent Zorbax SB C18柱(4.6×250 mm,5μm),流动相为乙腈(A)和水(B),梯度洗脱程序为:0~40 min,15.0~50.0%A;40~60 min,50.0~90.0%A。柱温为40℃,检测波长为290 nm,流速为1.0 mL/min。五种成分线性良好(R0.999),保留时间相对标准偏差(RSD)介于0.14~1.67%,峰面积RSD介于0.96~2.96%,加标回收率介于96.8~104.7%。优化了虎杖的提取条件,最佳条件为60%乙醇超声提取30 min。对10批虎杖样品分析结果表明:虎杖苷和大黄素-8-O-β-D-葡萄苷是虎杖乙醇提取物中两种含量最高的活性成分,含量范围分别为9.80~20.42 mg/g和5.56~24.45 mg/g。白藜芦醇和大黄素的含量范围分别为1.07~5.94 mg/g和3.79~17.85 mg/g,而大黄素甲醚含量为0.57~1.69 mg/g。该高效液相色谱法重复性好、精密度高,可用于虎杖中五种活性成分的同时测定。 相似文献