齿瓣石斛化学成分的研究

通过硅胶、Sephadex LH-20反复柱层析、纯化,从齿瓣石斛的茎中分离得到7个化合物,利用理化性质和波谱分析分别鉴定为新甘草苷(1)、3,5-二羟基黄酮-7-O-葡萄糖醛酸苷(2)、芦丁(3)、芹菜素-7-O-芸香糖苷(4)、芹菜素-7-O-葡萄糖苷(5)、β-胡萝卜苷(6)和β-谷甾醇(7)。以上化合物均为首次从齿瓣石斛中分离得到。     

抱茎苦荬菜水溶性成分的分离与结构鉴定

从抱茎苦荬菜的水溶性成分分离得到5个化合物,根据理化性质和光谱数据分别鉴定为木犀草素-7-O-β-D-葡萄糖醛酸苷(1),木犀草素-7-O-β-D-葡萄糖1→2葡萄糖苷(2),芹菜素-7-O-β-D-葡萄糖醛酸苷(3),菊苣酸(4),(-)3,4-二羟基咖啡酰基酒石酸(5)。化合物3～5为首次从该植物中分离得到。     

红背山麻杆化学成分的研究

采用柱色谱技术从红背山麻杆叶子的60％乙醇提取物中分离得到4个黄酮苷和2个其他类化合物.根据理化性质及波谱方法分别鉴定为:芹菜素-6-C-D-葡萄糖苷(1)、芹菜素-7-O-芸香糖苷(2)、芹菜素-7-O-β-(2″-O-α-鼠李糖基)葡萄糖醛酸苷(3)、木犀草素-7-O-α-L-鼠李糖(1→6)-β-D-葡萄糖苷(4)、没食子酸乙酯(5)、β-胡萝卜苷(6).以上化合物均为首次从该植物中分离得到,其中化合物1～4为首次从山麻杆属中分离得到的黄酮苷.     

厚朴叶中具血管舒张作用的化学成分研究

实验采用离体血管环灌流模型,观察厚朴叶正丁醇萃取部位对去甲肾上腺素预收缩的内皮完整和去除内皮的家兔离体血管环张力的影响。结果显示:厚朴叶正丁醇萃取部位对内皮完整和去除内皮的血管环在一定剂量内呈现浓度依赖性舒张作用,该作用可能与该部位大量成分———槲皮苷和芦丁有关。从该部位分离得到7个化合物,分别为槲皮苷(1),芦丁(2),紫丁香苷(3),丁香脂素-4,4’-双-O-β-D-葡萄糖苷(4),芥子醛-4-O-β-D-吡喃葡萄糖苷(5),松脂素-4-O-β-D-吡喃葡萄糖苷(6),丁香脂素-4-O-β-D-吡喃葡萄糖苷(7)。其中化合物4和6首次从该种植物中分离得到。     

鹿蹄草化学成分研究

从鹿蹄草(Pyrola callianthaH.Andres)中分离得到11个化合物,经光谱分析确定其结构为(4R)-1-四氢萘酮(1),(4S)-1-四氢萘酮(2),夹竹桃麻素(3),没食子酸(4),3,4-二羟基苯甲酸(5),鹿蹄草素(6),5-羟甲基糠醛(7),金丝桃苷(8),2″-O-没食子酰基金丝桃苷(9),鹿蹄草苷B(10),4-羟基-2,7-二甲基萘基-1-O-β-D-吡喃葡萄糖苷(11)。其中化合物1,2,3,5,6,11为首次从该植物中分离得到,化合物7为首次从该属中分离得到。     

裸花紫珠的化学成分

从裸花紫珠(Callicarpa nudiflora Hook.ex Arn.)地上部分的乙醇提取物中分离得到了7个化合物,经波谱分析确定其结构分别为:木犀草苷(1),木犀草素-3'-O-β-D-吡喃葡萄糖苷(2),木犀草素-4'-O-β-D-吡喃葡萄糖苷(3),2α,3α,19α-三羟基-乌索-12-烯-28-酸(4),乌索酸(5),2α-羟基-乌索酸(6)和齐墩果酸(7)。其中化合物2-7为首次从该植物中分离得到。     

云南产玉米须的化学成分研究

从玉米须60%乙醇提取液中分离得到了14个化合物,经波谱学方法分别鉴定为柯伊利素-7-O-β-D-葡萄糖苷(1)、柯伊利素-6-C-β-波伊文糖-7-O-β-葡萄糖苷(2)、柯伊利素-6-C-β-波伊文糖苷(3)、L-鼠李糖(4)、豆甾-4-烯-3β,6β-二醇(5)、7α-羟基谷甾醇(6)、7β-羟基谷甾醇(7)、胡萝卜苷棕榈酸酯(8)、大豆脑苷I(9)、7α-羟基谷甾醇-3-O-β-D-葡萄糖苷(10)、麦角甾-7,22-二烯-3β,5α,6β-三醇(11)、棕榈酸(12)、胡萝卜苷(13)和β-谷甾醇(14),其中化合物1、4和7～12为首次从玉米须中分离得到。     

松叶防风地上部分的化学成分

从松叶防风Seseli yunnanense Franch地上部分的乙醇提取物中分离鉴定了16个化合物,分别为金腰乙素(1),槲皮素(2),异槲皮苷(3),金丝桃苷(4),异鼠李素-3-O-葡萄糖苷(5),芹菜苷(6),芦丁(7),欧前胡素(8),蛇床子素(9),伞形花内酯(10),阿魏酸(11),falcarind iol(12),二十二烷醇(13),硬脂酸(14),β-谷甾醇(15),胡萝卜苷(16)。以上化合物均为首次从该种植物的地上部分中分离得到。研究结果表明松叶防风地上和地下部分共同的成分仅有8,12和15,地上和地下部分在化学成分方面有很大差别。     

蒙药材瑞香狼毒的化学成分研究

采用溶剂提取及柱色谱等方法,首次对瑞香狼毒Stellera chamaejasme L.的正丁醇萃取部位进行系统研究,分离得到6个苯丙素类化合物,并运用UV、1H NMR、13C NMR等现代波谱技术依次鉴定为伞形花内酯7-O-β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖苷(1),芥子醇1,3’-双-O-β-D-吡喃葡萄糖苷(2),紫丁香苷(3),(+)-落叶松树脂醇4,4’-O-β-D-吡喃葡萄糖苷(4),(+)-松树脂醇4,4’-O-双-β-D-吡喃葡萄糖苷(5)和(+)-丁香树脂醇-双-O-β-D-吡喃葡萄糖苷(6)。其中,化合物4、6为首次从该药材中分离得到。     

槐角化学成分及其抗骨质疏松作用研究

研究槐角的化学成分及其抗骨质疏松作用。利用硅胶柱、ODS反相硅胶柱、Sephadex LH-20凝胶柱和半制备型高效液相等色谱技术对槐角进行分离纯化,并结合化合物的理化性质和波谱数据确定化合物的结构。从槐角中分离得到15个化合物,分别为染料木素(1)、山萘酚(2)、鸢尾苷(3)、芒柄花苷(4)、α-鼠李异洋槐素(5)、鹰嘴豆芽素A-7-O-β-D-葡萄糖苷(6)、南酸枣苷(7)、thevetiaflavon(8)、香豌豆酚-7-O-β-D-葡萄糖苷(9)、山萘酚-7-O-β-D-葡萄糖苷(10)、槲皮苷(11)、山萘酚-3-O-β-D-槐糖苷(12)、染料木素-7,4'-双葡萄糖苷(13)、槲皮素-3-O-β-D-槐糖苷(14)、山萘酚-3-O-β-D-槐糖-7-O-α-L-鼠李糖苷(15)。其中化合物6~12、14为首次从该种植物中分离得到,化合物7、8、10、14为首次从该属植物中分离得到。对所分离的化合物进行了抗骨质疏松体外药理活性筛选,结果表明除化合物7和15以外,其他化合物均具有促进成骨细胞增殖作用。     

Effects of drought stress on phenolic accumulation in greenhouse-grown olive trees (Olea europaea)

The present study evaluates the effects of severe drought stress on the content of phenolic compounds in olive leaves, namely hydroxytyrosol, tyrosol, p-hydroxybenzoic acid, catechin, luteolin 7-O-rutinoside, luteolin 7-O-glucoside, apigenin 7-O-glucoside, quercetin, apigenin, pinoresinol, oleuropein and verbascoside in greenhouse-grown plantlets. The results showed that oleuropein, verbascoside, luteolin 7-O-glucoside and apigenin 7-O-glucoside were the most important phenolic compound of stressed olive plants and can represent up to 84% of the total amount of the identified phenolic compounds. Application of drought stress caused a significant increase in the level of oleuropein (87%), verbascoside (78%), luteolin 7-O-glucoside (72%) and apigenin 7-O-glucoside (85%), when compared to the control. The elevated values of these phenolic compounds can help controlling the water status of olive plants and avoiding serious oxidative damage induced by water deficit stress. To our knowledge, this is the first report to show the boost in the concentrations of verbascoside, luteolin 7-O-glucoside and apigenin 7-O-glucoside in the leaves of olive trees after water deficit stress.     

Sesquiterpene lactones,flavonoids and anthraquinones from Asphodeline globifera and Asphodeline Damascena

The known compounds chrysoeriol, apigenin, luteolin, acacetin, scutellarein, 6-methoxyluteolin, apigenin 7-glucoside, luteolin 7-glucoside, esculetin, chrysophanol, asphodeline, mircocarpin, sitosterol, 1-β-acetoxyeudesman-4(15),7(11)dien-2α,12-olide and 1-β-acetoxy-8β-hydroxyeudesman-4(15),7(11)-dien-8α,12-olide were isolated from Asphodeline globifera and A. damascena. A new sesquiterpene lactone 1-β-acetoxy-8β-ethoxyeudesman-4(15),7(11)dien-8α, 12-olide was also characterized. These are the first reports of sesquiterpene lactones in Asphodeline and in the Liliaceae.     

Apigenin 7-glucoside and its 2″- and 6″-acetates from ligulate flowers of Matricaria chamomilla

Dried ligulate flowers of Matricaria chamomilla contain 7–9% glucosides of apigenin and 0.3–0.5% free apigenin. Glucosides were identified as apigenin 7-glucoside and a 1:3 mixture of the 2″- and 6″-acetates, as determined by ¹³C NMR analysis.     

Flavone glycosides of some Launaea species

Eight flavone glycosides were isolated from Launaea nudicaulis and identified as apigenin 7-glucoside and 7-gentiobioside, luteolin 7-glucoside, 7-     

The in vivo incorporation of a flavanone into c-glycosylflavones

C-glycosylation, for the biogenesis of C-glycosylflavones, has been demonstrated to occur at the flavanone level for axenically-cultured Spirodela polyrhiza clone 7003. 4′,5,7-Trihydroxy[2-¹⁴C] flavanone (naringenin) was incorporated in a parallel manner into apigenin 7-O-glucoside and apigenin 8-C-glucoside (vitexin) and into luteolin 7-O-glucoside and luteolin 8-C-glucoside (orientin). In addition the data suggests that the enzyme which oxidizes flavanone (chalcone) to flavone is irreversible under the described experimental conditions.     

Flavonoids of Helichrysum chasmolycicum and its antioxidant and antimicrobial activities

From the aerial parts of Helichrysum chasmolycicum P.H Davis, which is an endemic species in Turkey, the flavonoids apigenin, luteolin, kaempferol, 3,5-dihydroxy-6,7,8-trimethoxyflavone, 3,5-dihydroxy-6,7,8,4′-tetramethoxyflavone, apigenin 7-O-glucoside, apigenin 4′-O-glucoside, luteolin 4′-O-glucoside, luteolin 4′,7-O-diglucoside, kaempferol 3-O-glucoside, kaempferol 7-O-glucoside and quercetin 3-O-glucoside were isolated. The methanol extract of the aerial parts of H. chasmolycicum showed antioxidant activity by DPPH method (IC₅₀ 0.92 mg/mL). Antimicrobial activity test was performed on the B, D, E extracts and also 3,5-dihydroxy-6,7,8-trimethoxyflavone and kaempferol 3-O-glucoside which were the major flavonoid compounds obtained from aerial parts of H. chasmolycicum by microbroth dilutions technique. The E (ethanol-ethyl acetate) extract showed moderate antimicrobial activity against Pseudomonas aeruginosa, B (petroleum ether-60% ethanol-chloroform) extract and 3,5-dihydroxy-6,7,8-trimethoxyflavone showed moderate antifungal activity against Candida albicans.     

Anaerobic degradation of flavonoids by Clostridium orbiscindens

An anaerobic, quercetin-degrading bacterium was isolated from human feces and identified as Clostridium orbiscindens by comparative 16S rRNA gene sequence analysis. The organism was tested for its ability to transform several flavonoids. The isolated C. orbiscindens strain converted quercetin and taxifolin to 3,4-dihydroxyphenylacetic acid; luteolin and eriodictyol to 3-(3,4-dihydroxyphenyl)propionic acid; and apigenin, naringenin, and phloretin to 3-(4-hydroxyphenyl)propionic acid, respectively. Genistein and daidzein were not utilized. The glycosidic bonds of luteolin-3-glucoside, luteolin-5-glucoside, naringenin-7-neohesperidoside (naringin), quercetin-3-glucoside, quercetin-3-rutinoside (rutin), and phloretin-2'-glucoside were not cleaved. Based on the intermediates and products detected, pathways for the degradation of the flavonol quercetin and the flavones apigenin and luteolin are proposed. To investigate the numerical importance of C. orbiscindens in the human intestinal tract, a species-specific oligonucleotide probe was designed and tested for its specificity. Application of the probe to fecal samples from 10 human subjects proved the presence of C. orbiscindens in 8 out of the 10 samples tested. The numbers ranged from 1.87 x 10(8) to 2.50 x 10(9) cells g of fecal dry mass(-1), corresponding to a mean count of 4.40 x 10(8) cells g of dry feces(-1).     

Anaerobic Degradation of Flavonoids by Clostridium orbiscindens

An anaerobic, quercetin-degrading bacterium was isolated from human feces and identified as Clostridium orbiscindens by comparative 16S rRNA gene sequence analysis. The organism was tested for its ability to transform several flavonoids. The isolated C. orbiscindens strain converted quercetin and taxifolin to 3,4-dihydroxyphenylacetic acid; luteolin and eriodictyol to 3-(3,4-dihydroxyphenyl)propionic acid; and apigenin, naringenin, and phloretin to 3-(4-hydroxyphenyl)propionic acid, respectively. Genistein and daidzein were not utilized. The glycosidic bonds of luteolin-3-glucoside, luteolin-5-glucoside, naringenin-7-neohesperidoside (naringin), quercetin-3-glucoside, quercetin-3-rutinoside (rutin), and phloretin-2′-glucoside were not cleaved. Based on the intermediates and products detected, pathways for the degradation of the flavonol quercetin and the flavones apigenin and luteolin are proposed. To investigate the numerical importance of C. orbiscindens in the human intestinal tract, a species-specific oligonucleotide probe was designed and tested for its specificity. Application of the probe to fecal samples from 10 human subjects proved the presence of C. orbiscindens in 8 out of the 10 samples tested. The numbers ranged from 1.87 × 10⁸ to 2.50 × 10⁹ cells g of fecal dry mass⁻¹, corresponding to a mean count of 4.40 × 10⁸ cells g of dry feces⁻¹.     

Apigenin 7-glucoside from Stachys tibetica Vatke and its anxiolytic effect in rats

BackgroundStachys tibetica Vatke (Himalayan or mountain tea) grows abundantly in the tropical and subtropical locations of the world including India, Tibet and China. The traditional healers of Kargil and adjoining areas in Ladakh, Jammu and Kashmir in India use the drug to treat fever, cough, phobias and various mental disorders etc. in the form of a decoction or as a tea. Flavonoids are important components in most herbal teas and play an important role in the management of various brain disorders via mimicking the action of benzodiazepines or through benzodiazepine receptors.Aim of the studyThe present study aimed to isolate flavonoids from S. tibetica and to evaluate their anxiolytic potential in comparison to reference synthetic (diazepam) and natural (apigenin) molecules.Materials and methodsS. tibetica root powder was extracted with 95% methanol for about 72 h using a soxhlet apparatus and the resultant extract was subjected to isolation procedures, resulting in the isolation of apigenin 7-glucoside and characterisation by various physical and spectrometric analyses. Apigenin 7-glucoside was evaluated for anxiolytic activity in rats in comparison with the reference compounds diazepam and apigenin using the elevated plus maze (EPM) model.ResultsPhytochemical investigations of S. tibetica revealed the presence of tannins, phenolics, flavonoids, saponins, glycosides and carbohydrates. A flavonoid glucoside, apigenin 7-glucoside was isolated for the first time from the roots of S. tibetica Vatke. The percentage of time spent and arm entries in the open arms was increased while the arms entries and duration of time spent in closed arms were decreased in the groups treated with apigenin 7-glucoside (which dose). In a similar fashion, diazepam and apigenin also exhibited anxiolytic activity (*p < 0.05, **p < 0.01). Apigenin 7-glucoside significantly decreased the percentage of head dips in EPM. Apigenin 7-glucoside showed anxiolytic potential comparable to the reference drugs apigenin and diazepam.ConclusionApigenin 7-glucoside could be an important molecule for the treatment of anxiety and further studies are required to elucidate its possible mechanism of action.     

Flavonoid pigments of butterflies in the genus Melanargia

Flavonoid pigments (18) were identified in the wings and body of Melanargia galathea: tricin, tricin 7-glucoside, tricin 7-diglucoside, tricin 4′-glucoside, luteolin, luteolin 7-glucoside, luteolin 7-diglucoside, luteolin 7-triglucoside, apigenin, apigenin 7-glucoside, orientin, orientin 7-glucoside, iso-orientin, iso-orientin 7-glucoside, vitexin 7-glucoside, vitexin 7-glucoside, isovitexin, isovitexin 7-glucoside and a novel but incompletely identified tricin 4′-conjugate. Examination of the wings and bodies of individual M. galathea, M. galathea var. procida, M. lachesis, M. russiae, M. larissa, M. occitanica and M. ines butterflies from a number of different populations in Europe by 2D PC revealed that variation in their flavonoid patterns was so minor that the flavonoid pattern of these Melanargia spp. may be considered constant. The concentration of flavonoids in the wings of each butterfly was greater than that in the body, as is the covering of scales. Not all flavonoids are located in the scales; some are also located in the reproductive tissues of the female. With the exception of the tricin 4′-conjugate which was absent from the egg and first instar larvae before feeding commences, these flavonoids were present in all the life stages of M. galathea. The presence of tricin 4′-conjugate in Melanargia but its absence from the larval food plants suggests that this compound is synthesized by the insect and that flavonoids are not merely sequestered from the diet but are also partly metabolized.