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1.
Anti-uveal melanoma activity-guided fractionation of the MeOH extract of Acacia nilotica pods resulted in the isolation of the new compound gallocatechin 5-O-gallate (5) in addition to methyl gallate (1), gallic acid (2), catechin (3), catechin 5-O-gallate (4), 1-O-galloyl-β-D-glucose (6), 1,6-di-O-galloyl-β-D-glucose (7) and digallic acid (8). The structures of the isolated compounds were elucidated on the basis of HRESIMS, NMR spectroscopy and CD data. In addition to uveal melanoma, the antiproliferative activities of the isolated compounds and the related compound epigallocatechin 3-O-gallate (EGCG) were evaluated against cutaneous melanoma, ovarian cancer, glioblastoma and normal retinal pigmented cells. 相似文献
2.
Li-Hua Zhang Yi-Ming Lin Gong-Fu Ye Xiao-Wei Liu Guang-Hui Lin 《Journal of Forest Research》2008,13(5):302-311
Changes in the N and P concentrations, N:P ratios, and tannin content in Casuarina equisetifolia branchlets across a coastal gradient were studied at Chishan Forestry Center of Dongshan County, Fujian Province, China.
(1) Total phenolics and protein precipitation capacity in young branchlets was significantly higher than in mature and senescent
branchlets across a coastal gradient; extractable condensed tannin content was higher in young and mature branchlets than
in senescent branchlets. Whereas protein-bound condensed tannins increased with senescence, fiber-bound condensed tannins
fluctuated without a consistent pattern; (2) N and P concentrations at various stages of branchlet development across a coastal
gradient followed the same order: young branchlets > mature branchlets > senescent branchlets; N:P ratio of young branchlets
was the lowest, and increased with maturity and senescence across a coastal gradient; phosphorus resorption efficiency was
significantly higher than nitrogen resorption efficiency among corresponding coastal gradients in response to P deficiency
(high N:P ratio), but nutrient resorption efficiency was influenced by coastal gradients; (3) significant linear relationships
between total phenolics and nutrient contents indicated that polyphenolics had a potential effect on nutrient cycling. 相似文献
3.
The Bradford protein quantification assay is based on an absorbance shift in Coomassie brilliant blue G-250 (CBB). Samples extracted for glomalin, a protein produced by arbuscular mycorrhizal (AM) fungi, are quantified using the Bradford assay. CBB is known to react with polyphenolic substances, and co-extraction of glomalin and humic substances is known to occur. The effects of increasing concentrations polyphenolic compounds were measured. The addition of any amount of polyphenolic compounds increased the Bradford reactive fraction (BRF) of soil extract. Caution is required when interpreting BRF data, as comparison of BRF data from different studies or different field sites is problematic. The BRF may represent recalcitrant organic material in soil, though its relationship to AM fungi remains unclear. 相似文献
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烟草多酚类化合物的研究进展 总被引:16,自引:0,他引:16
近年来,国外对烟草多酚类化合物已进行了广泛的研究.多酚在烟草的生长发育,烟草的调制特性,色泽和等级,以及烟气香味等各个方面起着重要作用.为了进一步提高对烟草多酚类化合物的认识,作者综述了国内外的文献,重点介绍栽培管理条件对烟草多酚的生理代谢影响和多酚对烟草和烟气芳香吃味的作用.本文还综述了烟草多酚的种类、特性、分布、生理功能、生物合成和遗传变异等内容. 相似文献
6.
Salvia miltiorrhiza Bunge is one of the most important and popular plant of the traditional Chinese medicine (TCM), but Salvia castanea Diels f. tomentosa Stib and Salvia miltiorrhiza Bunge f. alb have also been reported to have the same therapeutic effects as S. miltiorrhiza. To better distinguish between these species, the phytochemical profiles of three Salvia species were investigated by liquid chromatography. All the Salvia species were good sources of tanshinones, with the contents of phenolics being high in S. miltiorrhiza and S. miltiorrhiza f. alb, but not in S. castanea Diels f. tomentosa Stib. These results pave the way for a better phytotherapy exploitation of these plants. 相似文献
7.
[目的]探索燕麦成分的研究方法,对燕麦不同栽培种的种质资源进行评价。[方法]利用高效液相技术以及Folin-ciocalteu法研究不同燕麦的样品。[结果]确定从燕麦中提取多酚类化合物的工艺流程,并利用高效液相色谱技术研究不同样品中游离型和结合型多酚类化合物及抗氧化成分在燕麦中的分布情况以及燕麦中抗氧化成分的组成及存在形式;采用Folin-ciocalteu法测定不同样品提取液中总多酚含量,并测定不同样品结合型多酚类化合物清除DPPH自由基的能力。[结论]该研究为燕麦的综合利用提供依据。 相似文献
8.
Maurício Duarte-Almeida J Novoa AV Linares AF Lajolo FM Inés Genovese M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(4):187-192
Phenolic compounds in sugar cane (Saccharum officinarum L.) juice were identified and quantified by analytical high performance liquid chromatography and photodiode array detection, showing the predominance of flavones (apigenin, luteolin and tricin derivatives), among flavonoids, and of hydroxycinnamic, caffeic and sinapic acids, among phenolic acids, representing a total content of around 160 mg/L. A tricin derivative was present in the highest proportion (>10% of the total). The phenolic extract obtained from sugar cane juice showed a protective effect against in vivo MeHgCl intoxication and potent inhibition of ex vivo lipoperoxidation of rat brain homogenates, indicating a potential use for beneficial health effects and/or therapeutic applications. 相似文献
9.
Given that changes in the patterns of vegetation and size of carbon (C) pools in the Arctic are likely to be profound by the end of this century, it is necessary to characterise the identity and ecological groupings, in terms of temperature response and C substrate utilisation, of saprotrophic (decomposer) fungi in organic matter in Arctic soils. Thus, the aims of this study were: (1) to identify the fungi isolated from standing-dead material of Schistidium apocarpum, as an example of a High Arctic moss, (2) to determine mycelial extension rates of these fungi at a range of temperatures (4, 10 and 25 °C), and (3) to characterise the functional potential, defined by C substrate utilisation at 6 °C, of fungal taxa.Fungi were isolated at 4 °C from standing-dead material of S. apocarpum from an area of polar semi-desert (79 degrees N), close to Ny-Ålesund, Svalbard, in the High Arctic. From a collection of 662 isolates, 43 pure cultures were identified by DNA extraction, amplification, and sequencing. Phoma sclerotioides, previously known as a temperate snow mould, was isolated most frequently. The ecology of fifteen fungal isolates was characterised in detail. In terms of temperature response, two groups were apparent, one of truly psychrophilic/psychrotrophic fungi and one of more mesophilic fungi which were generally less frequently isolated. In terms of carbon substrate utilisation in semi-defined solid media, most fungi could utilise a variety of carbon substrates (degradation of casein, cellulose and starch was widespread), except for tannic acid (degraded by only two of the five P. sclerotioides isolates and Scytalidium lignicola) and lignin and chitin (not decomposed by any isolate). The majority of isolates had been recorded previously from polar environments and/or as being able to survive at low temperatures.Fungi in tundra ecosystems, therefore, have significant potential to mineralise C at temperatures below 10 °C. A better understanding of the ecology of these fungi will allow us to improve predictions of C dynamics in arctic biomes in the future. 相似文献
10.
葡萄总RNA提取方法的研究 总被引:63,自引:3,他引:63
针对葡萄组织中多酚、多糖类物质含量较高的特点,比较了改进SDS/酚法、异硫氰酸胍法和市售总RNA提取试剂盒等不同的提取方法,3种改进方法均能从葡萄幼嫩叶片中提取到总RNA。其中改进的SDS/酚法能有效抑制酚类物质和多糖对总RNA提取的影响,能够从成熟的叶片和完熟果实的果皮中获得质量高、完整性好的总RNA,28SrRNA亮度约为18SrRNA的2倍,A260/A280介于1.8~2.0之间,A260/A230大于2.0,且总RNA产率高,其中幼叶总RNA产率为261.20μg/g,成熟叶产率为191.40μg/g,完熟果皮产率为31.50μg/g,完全适于进行DDRT-PCR、Northernbolt和cDNA文库构建等研究。且该方法具有快速、简单、有效的特点。 相似文献