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Alexandra S. Silchenko Anatoly I. Kalinovsky Sergey A. Avilov Pelageya V. Andrijaschenko Roman S. Popov Pavel S. Dmitrenok Ekaterina A. Chingizova Vladimir I. Kalinin 《Marine drugs》2020,18(11)
Six new monosulfated triterpene tetra-, penta- and hexaosides, namely, the kurilosides A1 (1), A2 (2), C1 (3), D (4), E (5) and F (6), as well as the known earlier kuriloside A (7), having unusual non-holostane aglycones without lactone, have been isolated from the sea cucumber Thyonidium (= Duasmodactyla) kurilensis (Levin) (Cucumariidae, Dendrochirotida), collected in the Sea of Okhotsk near Onekotan Island from a depth of 100 m. Structures of the glycosides were established by 2D NMR spectroscopy and HR-ESI mass spectrometry. Kurilosides of the groups A and E contain carbohydrate moieties with a rare architecture (a pentasaccharide branched by C(4) Xyl1), differing from each other in the second monosaccharide residue (quinovose or glucose, correspondingly); kurilosides of the group C are characterized by a unique tetrasaccharide branched by a C(4) Xyl1 sugar chain; and kurilosides of the groups D and F are hexaosides differing from each other in the presence of an O-methyl group in the fourth (terminal) sugar unit. All these glycosides contain a sulfate group at C-6 of the glucose residue attached to C-4 Xyl1 and the non-holostane aglycones have a 9(11) double bond and lack γ-lactone. The cytotoxic activities of compounds 1–7 against mouse neuroblastoma Neuro 2a, normal epithelial JB-6 cells and erythrocytes were studied. Kuriloside A1 (1) was the most active compound in the series, demonstrating strong cytotoxicity against the erythrocytes and JB-6 cells and a moderate effect against Neuro 2a cells. 相似文献
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超临界流体萃取红芝三萜化合物 总被引:13,自引:0,他引:13
采用超临界流体设备,以CO2为萃取剂,从野生红芝子实体中萃取灵芝三萜化合物。分析了CO2密度、温度、时间及改性剂(甲醇)对红芝三萜化合物萃取的影响。 相似文献
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采用常规检测方法测定深层发酵樟芝菌丝体中的营养成分脂肪酸、氨基酸、麦角甾醇、总三萜的含量,用电感耦合等离子体质谱法测定矿物质的含量.结果表明:樟芝中粗脂肪的质量分数为11.61%,其中饱和脂肪酸占12.6%,不饱和脂肪酸占87.4%;粗蛋白的质量分数为34.20%,菌丝体干粉中总氨基酸含量为270.68 mg.kg-1;樟芝含有常量元素K、Na、P、Ca、Mg和多种人体所需的微量元素Fe、Zn、Mn、Cu、Mo、Cr、Se、Sr;樟芝中麦角甾醇的含量为19.55 mg.g-1,总三萜的含量为2.8125 mg.g-1.樟芝功效成分含量的测定有利于进一步探索其多种保健功能. 相似文献
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Two new chalcone glycosides 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′,4-dihydroxychalcone (1) and 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′-hydroxy-4-methoxychalcone (2) together with one known chalcone glycoside 4′-O-β-d-glucopyranosyl-2′-hydroxy-4-methoxychalcone (3) were isolated from the stems of Entada phaseoloides. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, 1H–1H COSY, and chemical evidences. This is the first report of chalcone-type compounds isolated from the genus Entada. 相似文献
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A field experiment was conducted to study the effect of planting material and plant density on stevia (Stevia rebaudiana Bertoni) under western Himalayan conditions during 2011 and 2012. The experiment conducted in a split plot design consisted of two types of planting material (rooted slips and fresh seedlings) in the main plot and five inter- and intra-row spacing in subplots with three replications. Yield attributes and dry leaf biomass yield of stevia were not affected by the type of planting material; however, plant density significantly influenced the yield attributes and leaf and stem dry biomass. Although the wider spacing (60 × 45 cm) gave more leaves, higher leaf area index, higher leaf dry mass per plant as compared to closer spacing, it resulted in lower values of these attributes per unit area. Plants spaced in 30 × 30 cm accumulated 41.2% and 42.8% more total biomass than 60 × 45 cm. Steviol glycoside content did not change due to different planting materials and plant densities; however, closer plant spacing (30 × 30 cm) recorded 114.8% and 70.0% higher steviol glycoside accumulation compared to wider row spacing (60 × 45 cm) in 2011 and 2012, respectively. 相似文献
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为了分析海南不同产地、不同生长环境和不同生长时期赤芝中多糖和三萜的含量。以葡萄糖为对照品,蒽酮显色,在625 nm波长下测定吸光度,分析多糖含量;以齐墩果酸为对照品,香草醛显色,在550 nm波长下测定吸光度,分析三萜含量。不同来源的赤芝多糖和三萜含量不同,霸王岭栽培赤芝的多糖含量最高,为1.59%;尖峰岭野生赤芝的三萜含量最高,为0.87%;其中同一产地不同生长环境的赤芝,多糖含量差异极显著(P<0.01),尖峰岭和五指山赤芝的三萜含量差异显著(P<0.05);相同生长环境不同产地的赤芝相互间的多糖含量差异极显著(P<0.01),尖峰岭和霸王岭野生赤芝三萜含量差异显著(P<0.05);不同生长时期的赤芝,多糖和三萜含量在菌蕾期和成熟期处于较高水平,衰退期明显下降。栽培赤芝的多糖含量均超过野生赤芝,野生赤芝的三萜含量相对更高;赤芝中的多糖和三萜含量在前3个时期保持在一个较高水平,成熟期为最佳采收时期。 相似文献