Neuroactive flavonoid glycosides from Tilia petiolaris DC. extracts

Pharmacological assay guided purification of an ethanol extract of Tilia petiolaris DC. inflorescences resulted in the isolation and identification of isoquercitrin (ISO), quercetin 3‐O‐glucoside‐7‐O‐rhamnoside (QUE) and kaempferol 3‐O‐glucoside‐7‐O‐rhamnoside (KAE). The behavioral actions of these glycosylated flavonoids were examined in the hole board, locomotor activity and thiopental‐induced loss of righting reflex tests in mice. QUE (10 and 30 mg/kg) and KAE (30 mg/kg), intraperitoneally (i.p.) administered to mice, reduced all the parameters measured in the hole board test, but ISO (30 mg/kg) only reduced the number of rearings. Meanwhile QUE at 30 mg/kg i.p. also decreased the ambulatory locomotor activity and increased the sodium thiopental‐induced time of loss of the righting reflex suggesting a clear depressant action. The above results demonstrate the occurrence of neuroactive flavonoid glycosides in Tilia. Copyright © 2009 John Wiley & Sons, Ltd.     

Eugenia punicifolia (Kunth) DC. as an Adjuvant Treatment for Type‐2 Diabetes Mellitus: A non‐Controlled,Pilot Study

Type‐2 diabetes mellitus (DM) is a highly prevalent disease with significant morbidity and mortality around the world. However, there is no universally effective treatment, because response to different treatment regimens can vary widely among patients. In this study, we aimed to investigate whether the use of the powdered dried leaves of Eugenia punicifolia (Kunth) DC. (Myrtaceae) is effective as an adjuvant to the treatment of patients with type‐2 DM. Fifteen patients were enrolled in a pilot, non‐controlled study, and received E. punicifolia for 3 months. After treatment, we observed a significant decrease in glycosylated hemoglobin, basal insulin, thyroid‐stimulating hormone, C‐reactive protein, and both systolic and diastolic blood pressure. There were no changes in fasting and postprandial glycemia. The compounds myricetin‐3‐O‐rhamnoside, quercetin‐3‐O‐galactoside, quercetin‐3‐O‐xyloside, quercetin‐3‐O‐rhamnoside, kaempferol‐3‐O‐rhamnoside, phytol, gallic acid, and trans‐caryophyllene present in the powdered dried leaves of E. punicifolia may be responsible for the therapeutic effect. In conclusion, the powdered leaves of E. punicifolia are promising as an adjuvant in the treatment of type‐2 DM and deserve further investigation. Copyright © 2014 John Wiley & Sons, Ltd.     

Evaluation of flavonoids from Bauhinia megalandra leaves as inhibitors of glucose-6-phosphatase system

From the methanol extract of Bauhinia megalandra fresh leaves, eight flavonoids were isolated and evaluated by rat liver microsomal glucose-6-phosphatase (G-6-Pase) bioassay, which might be a useful methodology for screening antihyperglycaemic substances. All the flavonoids assayed showed an inhibitory effect on the intact microsomal G-6-Pase: quercetin and kaempferol exhibited the lowest effect; astilbin, quercetin 3-O-alpha-rhamnoside, kaempferol 3-O-alpha-rhamnoside and quercetin 3-O-alpha-arabinoside an intermediate effect. The highest inhibitory activity was shown by quercetin 3-O-alpha-(2'-galloyl)rhamnoside and kaempferol 3-O-alpha-(2'galloyl)rhamnoside. None of the flavonoids mentioned above showed an inhibitory effect on the disrupted microsomal G-6-Pase. Quercetin 3-O-alpha-(2'-galloyl)rhamnoside and kaempferol 3-O-alpha-(2'-galloyl)rhamnoside exhibited the lowest IC50 of all the flavonoids assayed. Also, the phlorizin IC50 is reported.     

Investigation of CYP3A4 and CYP2D6 Interactions of Withania somnifera and Centella asiatica in Human Liver Microsomes

Withania somnifera is commonly used as a rejuvenator, whereas Centella asiatica is well known for its anxiolytic and nootropic effects. The present study aims at investigating the effect of crude extracts and principal phytoconstituents of both the medicinal plants with CYP3A4 and CYP2D6 enzyme activity in human liver microsomes (HLM). Phytoconstituents were quantified in the crude extracts of both the medicinal plants using reverse phase HPLC. Crude extracts and phytoconstituents of W. somnifera showed no significant interaction with both CYP3A4 and CYP2D6 enzymes in HLM. Of the crude extracts of C. asiatica screened in vitro, methanolic extract showed potent noncompetitive inhibition of only CYP3A4 enzyme (Ki—64.36 ± 1.82 µg/mL), whereas ethanol solution extract showed potent noncompetitive inhibition of only CYP2D6 enzyme (Ki—36.3 ± 0.44 µg/mL). The flavonoids, quercetin, and kaempferol showed potent (IC₅₀ values less than 100 μM) inhibition of CYP3A4 activity, whereas quercetin alone showed potent inhibition of CYP2D6 activity in HLM. Because methanolic extract of C. asiatica showed a relatively high percentage content of quercetin and kaempferol than ethanol solution extract, the inhibitory effect of methanolic extract on CYP3A4 enzyme activity could be attributed to the flavonoids. Thus, co‐administration of the alcoholic extracts of C. asiatica with drugs that are substrates of CYP3A4 and CYP2D6 enzymes may lead to undesirable herb‐drug interactions in humans. Copyright © 2015 John Wiley & Sons, Ltd.     

Antihyperlipidemic Components of Cassia auriculata Aerial Parts: Identification Through In Vitro Studies

Cassia auriculata (Caesalpiniaceae) is a common Asian beverage and medicinal plant widely used in tradition medicine for diabetes, hyperlipidemia and various other disease conditions. Previous studies on crude extracts of C. auriculata have documented the scientific basis for some of its traditional medicinal uses. The present study investigates the antilipase activity of the ethanol extract of the aerial parts along with the previously isolated compounds (kaempferol‐3‐O‐rutinoside, rutin, kaempferol, quercetin and luteolin). The crude extract displayed inhibitory activity against pancreatic lipase with IC₅₀ of 6.0 ± 1.0 µg/mL. The most active antilipase compound was kaempferol‐3‐O‐rutinoside with IC₅₀ value (2.9 ± 0.50 μM) only about twice weaker than the standard antilipase drug, orlistat (IC₅₀ = 1.45 ± 0.26 μM). Luteolin, quercetin and rutin were found to be weak pancreatic lipase inhibitors (IC₅₀ over 100 μM), whereas kaempferol showed no activity up to 250 μM. The antihyperlipidemic effect of C. auriculata could be attributed to direct lipase inhibitory effect of the plant constituents. Copyright © 2012 John Wiley & Sons, Ltd.     

三七茎叶黄酮类成分的研究

 目的对三七[Panax notoginseng(Burk.)F.H.Chen]茎叶的黄酮类成分进行分离鉴定。方法利用水煎煮提取、大孔吸附树脂吸附、硅胶柱色谱、ODS柱色谱等方法分离提纯,通过理化性质及IR,UV,MS,¹H-NMR,¹³C-NMR等光谱数据鉴定其结构。结果分离得到6个黄酮类单体化合物,分别鉴定为:山柰酚(kaempferol,Ⅰ)、槲皮素(quercetin,Ⅱ)、山柰酚-7-O-α-L-鼠李糖苷(kaempferol 7-O-α-L-rhamnoside,Ⅲ)、山柰酚-3-O-β-D-半乳糖苷(kaempferol 3-O-β-D-galactoside,Ⅳ)、山柰酚-3-O-β-D-半乳糖(2→1)葡萄糖苷[kaempferol 3-O-(2″-β-D-glucopyranosyl)-β-D-galactopyranoside,Ⅴ]、槲皮素-3-O-β-D-半乳糖(2→1)葡萄糖苷[quercetin3-O-(2″-β-D-glucopyranosyl)-β-D-galactopyranoside,Ⅵ]。结论除山柰酚(kaempferol,Ⅰ)、槲皮素(quercetin,Ⅱ)之外,其余4个化合物皆为首次从该植物中分离得到,Ⅲ与Ⅵ为首次从该属植物中分离得到。     

基于一测多评法研究畲药食凉茶黄酮类物质动态变化规律

目的一测多评(QAMS)法测定畲药食凉茶中4种黄酮类成分,并以其研究食凉茶黄酮类物质的动态变化规律。方法以芦丁为参照物,分别建立其与山柰酚-3-O-芸香糖苷、槲皮素、山柰素的相对校正因子(f),并计算食凉茶中各成分量,实现QAMS。同时采用外标法验证QAMS法的准确性和可行性。结果芦丁与山柰酚-3-O-芸香糖苷、槲皮素和山柰素的f分别为1.158、0.475 6、0.431 9,RSD分别为0.73%、1.55%、1.58%;QAMS法测定结果与外标法测定结果无显著差异。不同月份食凉茶中黄酮类成分质量分数差异明显,2个来源食凉茶之间的量差异亦较明显。结论以芦丁为参照物同时测定山柰酚-3-O-芸香糖苷、槲皮素、山柰素的QAMS法可用于畲药食凉茶的定量分析。以黄酮类物质为指标,食凉茶的最佳采收期为7月和8月。     

Chemical and biological investigations on Zizyphus spina-christi L.

Different extracts and fractions of the leaves, fruits and seeds of Zizyphus spina-christi L. grown in Egypt were investigated in vitro for their antiviral, antifungal and antibacterial activities. The flavonoids quercetin, hyperoside, rutin and quercetin-3-O-[beta-xylosyl-(1-2)-alpha-rhamnoside] 4'-O-alpha- rhamnoside) were isolated.     

In vitro protective effects of an aqueous extract of Clitoria ternatea L. flower against hydrogen peroxide‐induced cytotoxicity and UV‐induced mtDNA damage in human keratinocytes

The traditional practice of eating the flowers of Clitoria ternatea L. or drinking their infusion as herbal tea in some of the Asian countries is believed to promote a younger skin complexion and defend against skin aging. This study was conducted to investigate the protective effect of C. ternatea flower water extract (CTW) against hydrogen peroxide‐induced cytotoxicity and ultraviolet (UV)‐induced mitochondrial DNA (mtDNA) damage in human keratinocytes. The protective effect against hydrogen peroxide‐induced cytotoxicity was determined by 3‐(4, 5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium assay, and mtDNA damage induced by UV was determined by polymerase chain reaction. Preincubation of HaCaT with 100, 250, and 500 μg/ml CTW reduced cytotoxicity effects of H₂O₂ compared with control (H₂O₂ alone). CTW also significantly reduced mtDNA damage in UV‐exposed HaCaT (p < .05). CTW was chemically‐characterized using high resolution liquid chromatography–mass spectrometry. The main compounds detected were assigned as anthocyanins derived from delphinidin, including polyacylated ternatins, and flavonol glycosides derived from quercetin and kaempferol. These results demonstrated the protective effects of C. ternatea flower extracts that contain polyacylated anthocyanins and flavonol glycosides as major constituents, against H₂O₂ and UV‐induced oxidative stress on skin cells, and may provide some explanation for the putative traditional and cosmetic uses of C. ternatea flower against skin aging.     

Tyrosinase and Cholinesterase Inhibitory Potential and Flavonoid Characterization of Viola odorata L. (Sweet Violet)

Inhibitory potential of the dichloromethane, ethyl acetate, ethanol, and aqueous extracts of Viola odorata L. (VO) was investigated against tyrosinase (TYR) and cholinesterases by microplate assays. The antioxidant activity was tested using six in vitro assays. Only the ethanol extract inhibited TYR (80.23 ± 0.87% at 100 µg mL^?1), whereas none of them were able to inhibit cholinesterases. The extracts were more able to scavenge NO radical (31.98 ± 0.53–56.68 ± 1.10%) than other radicals tested, and displayed low to moderate activity in the rest of the assays. HPLC analysis revealed that the aqueous extract of VO contained a substantial amount of vitexin (18.81 ± 0.047 mg g^?1 extract), while the ethanol extract also possessed rutin (1.31 ± 0.013 mg g^?1 extract) and vitexin (4.65 ± 0.103 mg g^?1 extract). Furthermore, three flavonoids (rutin, isovitexin, and kaempferol‐6‐glucoside) were isolated from the ethanol extract. This is the first report on TYR inhibitory activity of VO as well as presence of vitexin and isovitexin in this species. Copyright © 2015 John Wiley & Sons, Ltd.     

不同水分梯度下垂盆草生长发育、品质及抗氧化活性关系研究

目的研究水分对垂盆草生长发育、有效成分积累及体外抗氧化能力的影响,探索高产优质垂盆草的水分条件。方法设置5个水分处理,分别为田间持水量的15%~20%(S1)、35%~40%(S2)、55%~60%(S3)、75%~80%(S4)、95%~100%(S5),收获时测定生长指标、产量、多种活性成分含量及多种体外抗氧化能力。结果 S4处理显著提高垂盆草最大分枝长、叶片层数、分枝数,而S1处理导致植株生长受抑。总黄酮含量以S4处理最高,S3处理次之,S5处理最低。总酚含量以S3处理最高,但与S4处理无显著差异。各处理槲皮素、山柰素、异鼠李素及三者总含量的差异达到显著水平,均以S1处理最高,S4、S3处理次之,S5处理最低。S4处理获得最高活性成分产量,S5处理次之,S1处理最低。垂盆草水提物清除DPPH自由基、抑制脂质过氧化能力(TBARS法)及还原能力均以S4处理最强。抑制脂质过氧化能力与槲皮素含量、异鼠李素含量、3种黄酮类成分总含量均呈显著正相关。结论综合比较垂盆草药材产量、活性成分含量和抗氧化能力,75%~80%田间持水量的土壤水分利于垂盆草高产优质兼得。     

Antiprotozoal activities of Centipeda minima

In vitro activity against Giardia intestinalis was used for bioassay-guided fractionation of crude extracts from C. minima. The sesquiterpene lactone, brevilin A was isolated and found to have antigiardial activity (IC₅₀ = 16.1 μM) and was similarly active in vitro against Entamoeba histolytica (IC₅₀ between 4.5 and 9 μM) and against Plasmodium falciparum (IC₅₀ = 9.42 μM). Three flavonoids, quercetin, quercetin 3-methyl ether and kaempferol 7-glucosylrhamnoside were also isolated.     

加拿大一枝黄花黄酮类成分及抗氧化与自由基消除活性的研究

 目的研究外来植物加拿大一枝黄花中黄酮类成分及其抗氧化和自由基消除活性。方法应用多种色谱技术进行分离纯化,应用MS和NMR技术鉴定化合物的结构,采用1,1-二苯基苦味基苯肼(DPPH)自由基消除实验进行抗氧化和自由基消除活性的研究。结果从加拿大一枝黄花的甲醇提取物中分离鉴定出9个黄酮类化合物,分别鉴定为:槲皮素(1)、3-甲氧基槲皮素(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、槲皮素-3-O-α-L-鼠李糖苷(4)、芦丁(5)、山柰酚(6)、山柰酚-3-O-β-D-葡萄糖苷(7)、山柰酚-3-O-α-L-鼠李糖苷(8)、山柰酚-3-O-芦丁糖苷(9);自由基消除实验发现,与维生素C相比,化合物1的抗氧化和自由基消除活性最强,化合物2和3显示出中等活性,化合物4~9的活性较弱。结论化合物2,4,8和9首次从该植物中得到,加拿大一枝黄花中的黄酮类成分具有较强的抗氧化和自由基消除活性,其活性强弱与分子结构相关。     

Extracts from Epilobium sp. Herbs,Their Components and Gut Microbiota Metabolites of Epilobium Ellagitannins,Urolithins, Inhibit Hormone‐Dependent Prostate Cancer Cells‐(LNCaP) Proliferation and PSA Secretion

Extracts from Epilobium sp. herbs have been traditionally used in the treatment of prostate‐associated ailments. Our studies demonstrated that the extracts from Epilobium angustifolium, Epilobium parviflorum and Epilobium hirsutum herbs are potent prostate cancer cells (LNCaP) proliferation inhibitors with IC₅₀ values around 35 µg/ml. The tested extracts reduced prostate specific antigen (PSA) secretion (from 325.6 ± 25.3 ng/ml to ~90 ng/ml) and inhibited arginase activity (from 65.2 ± 1.1 mUnits of urea/mg of protein to ~40 mUnits of urea/mg protein). Selected constituents of extracts (oenothein B, quercetin‐3‐O‐glucuronide, myricetin‐3‐O‐rhamnoside) were proven to be active in relation to LNCaP cells. However, oenothein B was the strongest inhibitor of cells proliferation (IC₅₀ = 7.8 ± 0.8 μM), PSA secretion (IC₅₀ = 21.9 ± 3.2 μM) and arginase activity (IC50 = 19.2 ± 2.0 μM). Additionally, ellagitannins from E. hirustum extract were proven to be transformed by human gut microbiota into urolithins. Urolithin C showed the strongest activity in the inhibition of cell proliferation (IC₅₀ = 35.2 ± 3.7 μM), PSA secretion (reduced PSA secretion to the level of 100.7 ± 31.0 ng/ml) and arginase activity (reduced to the level of 27.9 ± 3.3 mUnits of urea/mg of protein). Results of the work offer an explanation of the activity of Epilobium extracts and support the use of Epilobium preparations in the treatment of prostate diseases. Copyright © 2013 John Wiley & Sons, Ltd.     

Chemical Composition and Immuno‐Modulatory Effects of Urtica dioica L. (Stinging Nettle) Extracts

The purpose of this work was to determine the chemical profile of stinging nettle and to provide an insight into the mechanisms by which it ameliorates the immune response. Qualitative and quantitative liquid chromatography tandem mass spectrometry analyses indicated that phenolic acids (5‐O‐caffeoylquinic acid as dominant) and flavonol glycosides (rutin, isoquercitrin, and kaempferol 3‐O‐glucoside) are present in the aerial parts, while lignans (secoisolariciresinol, 9,9′‐bisacetyl‐neo‐olivil and their glucosides) were detected in the root. Herb and root extracts expressed selective inhibition toward cyclooxygenase and lipoxygenase branches in human platelets: root extracts were better at inhibiting thromboxane production, while herb extracts were more specific toward inhibition of 12‐lipoxygenase pathway. Stinging nettle extracts mildly increased monocyte chemoattractant protein‐1 and growth‐related oncogene release from nonstimulated intestinal epithelial cells, stimulating MyD88/NF‐κB/p38 signaling, hence preserving the epithelial integrity and enhancing intestinal steady‐state defense. Additionally, root extract reduced lipopolysaccharide‐induced monocyte chemoattractant protein‐1/growth‐related oncogene secretion and cyclooxygenase‐2 expression in intestinal epithelial cells, thus showing the potential protective effect against tissue damage caused by inflammation processes. These observations suggest that stinging nettle is an interesting candidate for the development of phytopharmaceuticals or dietary supplements for cotreatment of various inflammatory diseases, particularly inflammatory bowel diseases. Copyright © 2017 John Wiley & Sons, Ltd.     

Investigation of diuretic drug plants. 1. Phytochemical screening and pharmacological evaluation of Anethum graveolens L., Apium graveolens L., Daucus carota L. and Eruca sativa mill

A preliminary phytochemical screening of fruits of Anethum graveolens L., Apium graveolens L., Daucus carota L., and seeds of Eruca sativa Mill., revealed the presence of volatile oil, sterols and/or triterpenes, carbohydrates and/or glycosides, tannins and flavonoids in the four entitled plants; Glucosinolates were detected only in Eruca seeds. Pharmacological evaluation of the aforementioned plants for diuretic activity has shown the ethanolic extracts of Eruca sativa seeds and fruits of Anethum graveolens, Daucus carota as well as the volatile oils in the former two plants to produce an increase in urine flow in dogs. Volatile oil of Eruca seeds, significantly, increased Na⁺, K⁺ and Cl^? excretion in urine, whereas Anethum graveolens volatile oil significantly increased Na⁺ and Cl^? excretion only.     

金花茶中黄酮类活性成分的GC-MS分析

目的:建立石墨烯-搅拌棒吸附萃取(SBSE)结合气相色谱-质谱联用(GC-MS)分析金花茶中黄酮类活性成分并对总黄酮的相对含量进行测定。方法:自制稻草源活性炭制备石墨烯聚合物,实验中对影响SBSE的因素(萃取涂层选择、萃取温度和时间等)进行了优化,用GC-MS鉴定金花茶中黄酮类活性成分,在所得优化条件下采用峰面积归一化法对金花茶中总黄酮相对含量进行测定。结果:样品中黄酮类活性成分经鉴定有儿茶素,表没食子儿茶素(EGC),儿茶酚(C),槲皮素-7-O-葡萄糖苷,芦丁,异槲皮苷,花青素,槲皮素,山柰酚,儿茶素没食子酸酯(CG),儿茶素没食子酸酯(CG)等,经检测金花茶中总黄酮相对含量(主要为槲皮素和山柰酚)达到3.0%。同一样品经6次测定,以金花茶总黄酮的总峰面积值为考察指标,其RSD 1.0%。结论:建立的SBSE-GC-MS方法分离鉴定出24个成分,测定金花茶总黄酮相对含量重复性较好,适于金花茶黄酮类成分的分析检测,为金花茶黄酮类活性成分的进一步研究提供了理论参考。     

Polyphenolic Compounds and Antioxidant Activity of Cold‐Pressed Seed Oil from Finola Cultivar of Cannabis sativa L.

The aim of this study was to characterize the polyphenolic compounds and antioxidant activity of cold‐pressed seed oil from Finola cultivar of industrial hemp (Cannabis sativa L.). Several methodologies have been employed to evaluate the in vitro antioxidant activity of Finola hempseed oil (FHSO) and both lipophilic (LF) and hydrophilic fractions (HF). The qualitative and quantitative composition of the phenolic fraction of FHSO was performed by HPLC analyses. From the results is evident that FHSO has high antioxidative activity, as measured by DPPH radical (146.76 mmol of TE/100 g oil), inhibited β‐carotene bleaching, quenched a chemically generated peroxyl radical in vitro and showed high ferrous ion chelating activity. Reactivity towards 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cation and ferric‐reducing antioxidant power values were 695.2 µmol of TE/100g oil and 3690.6 µmol of TE/100 g oil respectively. FHSO contains a significant amount of phenolic compounds of which 2780.4 mg of quercetin equivalent/100 g of total flavonoids. The whole oil showed higher antioxidant activity compared with LF and HF. Our findings indicate that the significant antioxidant properties shown from Finola seed oil might generally depend on the phenolic compounds, especially flavonoids, such as flavanones, flavonols, flavanols and isoflavones. Copyright © 2016 John Wiley & Sons, Ltd.     

Phytochemical and Pharmacological Investigations on Nymphoides indica Leaf Extracts

Nymphoides indica (L.) Kuntze (Menyanthaceae) is traditionally used in the Indian subcontinent. However, scientific data reporting its constituents are poor. This study aimed at evaluating its phytochemical constituents and various biological activities. Phytochemical investigations of the extracts and fractions resulted in the isolation of 5 lipophilic compounds, i.e. azelaic (nonanedioic) acid (1) and 4‐methyl‐heptanedioic acid (3), hexadecanoic (2) and stearic acid (5) and the fatty alcohol hexadecanol (4); 3 seco‐iridoids, i.e. 7‐epiexaltoside (6), 6″,7″‐dihydro‐7‐epiexaltoside (7) and menthiafolin (8); 3 flavonoids, i.e. 3,7‐di‐O‐methylquercetin‐4′‐O‐β‐glucoside (9), 3‐O‐methylquercetin‐7‐O‐β‐glucoside (10) and 3,7‐di‐O‐methylquercetin (11); scopoletin (12) and ferulic acid (13); and the monoterpenoids foliamenthoic acid (14) and 6,7‐dihydrofoliamenthoic acid methyl ester (15). Compounds 1–5 showed moderate antimicrobial activities, whereas compound 9 presented mild antiprotozoal activities against Trypanosoma brucei (IC₅₀ 8 μM), Leishmania infantum (IC₅₀ 32 μM) and Trypanosoma cruzi (IC₅₀ 30 μM). Antiglycation activity was shown by compounds 7 (IC₅₀ 0.36 mM), 10 (IC₅₀ 0.42 mM) and 15 (IC₅₀ 0.61 mM). Finally α‐glucosidase inhibition was shown by compounds 7, 9, 11 and 13–15. It could be concluded that N. indica leaf extracts possess mild to moderate antimicrobial, antiprotozoal, antioxidant and antidiabetic activities. Copyright © 2016 John Wiley & Sons, Ltd.