Antiprotozoal activity of Melampyrum arvense and its metabolites

An activity guided isolation of the H₂O subextract of the crude extract of Melampyrum arvense L. afforded iridoid glucosides: aucubin (1), melampyroside (2), mussaenoside (3), mussaenosidic acid (4), 8‐epi‐loganin (5); flavonoids: apigenin (6), luteolin (7), luteolin 7‐O‐β‐glucopyranoside (8); a lignan glycoside dehydrodiconiferyl alcohol 9‐O‐β‐glucopyranoside (9); and benzoic acid (10). β‐Sitosterol (11) and a fatty acid mixture (12) were identified as the active principles of the CHCl₃ subextract. The structures of the isolates were elucidated by spectroscopic methods, while the composition of 12 was identified by GC‐MS after methylation. Luteolin (7) appeared as the most active compound against Trypanosoma brucei rhodesiense and Leishmania donovani (IC₅₀ values 3.8 and 3.0 μg/mL). Luteolin 7‐O‐β‐glucopyranoside (8) displayed the best antiplasmodial activity against Plasmodium falciparum (IC₅₀ value 2.9 μg/mL). This is the first detailed phytochemical study on Turkish M. arvense and the first report of the antiprotozoal effect of Melampyrum species and its constituents. Copyright © 2010 John Wiley & Sons, Ltd.     

Anti‐inflammatory effects of chemical components from Ginkgo biloba L. male flowers on lipopolysaccharide‐stimulated RAW264.7 macrophages

Ginkgo biloba L., well known as living fossil, have various pharmacological activities. Eighteen compounds were isolated from Ginkgo male flowers including a novel matsutake alcohol glycoside, Ginkgoside A ( 1 ), and 17 known compounds—calaliukiuenoside ( 2 ), benzylalcohol O‐α‐l ‐arabinopyranosyl‐(1 → 6)‐β‐d ‐glucopyranoside ( 3 ), amentoflavone ( 4 ), sciadopitysin ( 5 ), bilobetin ( 6 ), isoginkgetin ( 7 ), olivil 4‐O‐β‐d ‐glucopyranoside ( 8 ), dihydrodehydrodiconiferyl alcohol‐4‐O‐β‐d ‐glucoside ( 9 ), (+)‐cyclo‐olivil‐6‐O‐β‐d ‐glucopyranoside ( 10 ), (?)‐isolariciresinol 4‐O‐β‐d ‐glucopyranoside ( 11 ), coniferin ( 12 ), trans‐cinnamic acid‐4‐O‐β‐d ‐glucopyranoside ( 13 ), p‐coumaryl alchol glucoside ( 14 ), stroside B ( 15 ), methylconiferin ( 16 ), cis‐p‐coumaric acid 4‐O‐β‐d ‐glucopyranoside ( 17 ), and cis‐coniferin ( 18 ). Thirteen of these compounds had not previously found in Ginkgo. All extractive fractions and isolated compounds were evaluated for their anti‐inflammatory ability in the lipopolysaccharide‐induced RAW264.7 macrophages. The ethanol extract of Ginkgo flowers and the chloroform and ethyl acetate fractions can significantly decrease nitric oxide (NO), interleukin‐6 (IL‐6), and prostaglandin E₂ (PGE₂) production at 100 μg/ml. The most effective compounds, bilobetin ( 6 ) and isoginkgetin ( 7 ), elevated the NO inhibition ratios to 80.19% and 82.37% at 50 μM, respectively. They also exhibited significant dose‐dependent inhibitory effects on tumor necrosis factor‐α, IL‐6, PGE₂, inducible NO synthase mRNA, and cyclooxygenase‐2 mRNA levels. So they can be promising candidates for the development of new anti‐inflammatory agents.     

Biological Activities of Oleanolic Acid Derivatives from Calendula officinalis Seeds

Phytochemical examination of butanol fraction of Calendula officinalis seeds led to the isolation of two compounds identified as 28‐O‐β‐D‐glucopyranosyl‐oleanolic acid 3‐O‐β‐D–glucopyranosyl (1→3)‐β‐D‐glucopyranosiduronic acid (CS1) and oleanolic acid 3‐O‐β‐D–glucopyranosyl (1→3)‐β‐D‐glucopyranosiduronic acid (CS2). Biological evaluation was carried out for these two compounds such as melanin biosynthesis inhibitory, hyaluronic acid production activities, anti obesity using lipase inhibition and adipocyte differentiation as well as evaluation of the protective effect against hydrogen peroxide induced neurotoxicity in neuro‐2A cells. The results showed that, compound CS2 has a melanin biosynthesis stimulatory activity; however, compound CS1 has a potent stimulatory effect for the production of hyaluronic acid on normal human dermal fibroblast from adult (NHDF‐Ad). Both compounds did not show any inhibitory effect on both lipase and adipocyte differentiation. Compound CS2 could protect neuro‐2A cells and increased cell viability against H₂O₂. These activities (melanin biosynthesis stimulatory and protective effect against H₂O₂ of CS2 and hyaluronic acid productive activities of these triterpene derivatives) have been reported for the first time. Copyright © 2016 John Wiley & Sons, Ltd.     

Compounds with tyrosinase inhibition, elastase inhibition and DPPH radical scavenging activities from the branches of Distylium racemosum Sieb. et Zucc

Twenty compounds were isolated from the ethanol extract of Distylium racemosum branches and their inhibitory activities on tyrosinase, elastase and free radicals evaluated. The isolated compounds were identified as dibenzofurans (1–4), abscisic acid (5), 6′‐O‐galloylsalidroside (6), catechin derivatives (7–11), gallic acid derivatives (12–14), tyrosol (15), flavonoids (16–18), lupeol (19) and 1,2,3,6‐tetragalloylglucose (20). For study of tyrosinase inhibition activities, when compared with arbutin (IC₅₀ 48.8 μg/mL), four compounds (8, 11, 13, 17) showed higher activities, with IC₅₀ values of 4.8, 30.2, 40.5 and 37.7 μg/mL, respectively. For the elastase inhibition test, dibenzofuran 1 showed greater activity than the positive control, oleanolic acid (IC₅₀ 9.7 μg/mL), with an IC₅₀ of 7.7 μg/mL. In the studies on DPPH radical scavenging activities, five compounds (11, 12, 13, 14, 15) showed higher activities than ascorbic acid (IC₅₀ 5.0 μg/mL), with IC₅₀ values of 4.6, 3.9, 2.9, 3.8 and 4.7 μg/mL, respectively. Copyright © 2011 John Wiley & Sons, Ltd.     

Chemical Composition and Biological Activities of Polar Extracts and Essential Oil of Rose‐scented Geranium,Pelargonium graveolens

Pelargonium graveolens (Geraniaceae) was characterized with respect to its chemical composition, antioxidant potential and antimicrobial activities. This is the first investigation focusing on the comparison of both essential oil and polar extracts from this species. The chemical composition of the essential oil of the aerial parts of P. graveolens was analyzed by gas chromatography/mass spectrometry. The main constituents of the oil were found to be β‐citronellol (21.9%), citronellyl formate (13.2%), geraniol (11.1%), 10‐epi‐γ‐eudesmol (7.9%), geranyl formate (6.2%) and (l)‐linalool (5.6%). Nine flavonoids were identified by high‐performance liquid chromatography–MS in leaf and flower extracts. Kaempferol 3‐O‐rhamnoside‐glucoside, isorhamnetin aglycone, quercetin 3‐O‐glucoside, kaempferol 3,7‐di‐O‐glucoside, quercetin 3‐O‐pentose and kaempferol 3‐O‐glucoside, quercetin 3‐O‐rhamnoside‐glucoside, quercetin 3‐O‐pentoside‐glucoside, myrisetin 3‐O‐glucoside‐rhamnoside flavonoids were detected in methanolic and aqueous extracts, respectively. The total flavonoids ranged between 29.9 and 78.2 mg QE/g in flower water and methanol extracts, respectively, and 22.5 and 71.2 mg QE/g dry weight in leaf water and methanol extracts, respectively. The highest antioxidant activities using two methods of free radical scavenging capacities were obtained with the essential oil (9.16 mM of Trolox and 2.68 µg/ml). All P. graveolens essential oil and polar extracts were active against at least one bacterium. Copyright © 2012 John Wiley & Sons, Ltd.     

Inhibitory Activities of Thai Medicinal Plants with Promising Activities Against Malaria and Cholangiocarcinoma on Human Cytochrome P450

Malaria and cholangiocarcinoma remain important public health problems in tropical countries including Southeast Asian nations. Newly developed chemotherapeutic and plant‐derived drugs are urgently required for the control of both diseases. The aim of the present study was to investigate the propensity to inhibit cytochrome P450‐mediated hepatic metabolism (CYP1A2, CYP2C19, CYP2D6 and CYP3A4) of the crude ethanolic extract of eight Thai medicinal plants with promising activities against malaria and cholangiocarcinoma, using human liver microsomes in vitro. Piper chaba Linn. (PC) and Atractylodes lancea (thung.) DC. (AL) exhibited the most potent inhibitory activities on CYP1A2‐mediated phenacetin O‐deethylation with mean IC₅₀ of 0.04 and 0.36 µg/mL, respectively. Plumbago indica Linn. (PI) and Dioscorea membranacea Pierre. (DM) potently inhibited CYP2C19‐mediated omeprazole 5‐hydroxylation (mean IC₅₀ 4.71 and 6.92 µg/mL, respectively). DM, Dracaena loureiri Gagnep. (DL) and PI showed the highest inhibitory activities on dextromethorphan O‐demethylation (mean IC₅₀ 2.93–9.57 µg/mL). PC, DM, DL and PI exhibited the most potent inhibitory activities on CYP3A4‐mediated nifedipine oxidation (mean IC₅₀ 1.54–6.43 µg/mL). Clinical relevance of the inhibitory potential of DM, PC and PI is of concern for the further development of these plants for the treatment of malaria and/or cholangiocarcinoma. Copyright © 2015 John Wiley & Sons, Ltd.     

Inhibitory Effect of Verbascoside Isolated from Buddleja brasiliensis Jacq. ex Spreng on Prolyl Oligopeptidase Activity

The phenylpropanoid glycoside verbascoside [2‐(3,4‐dihydroxyphenylethyl)‐1‐O‐α‐l ‐rhamnopyranosyl‐(1→3)‐β‐d ‐(4‐O‐caffeyl)‐glucopyranoside] (1) has been isolated as the main constituent of the crude extract of Buddleja brasiliensis Jacq. ex Spreng from Southern Brazil. The crude extract, main fractions and the compound 1 were evaluated for inhibition of the enzymes acetylcholinesterase (AChE), dipeptidyl peptidase‐IV (DPP‐IV) and prolyl oligopeptidase (POP). Compound 1 showed weak activity against DPP‐IV with an IC₅₀ >> 150 µm and was inactive against AChE, with a pMIQ determined by bioautography of 9.6. In contrast, 1 displayed significant inhibition of POP in a dose‐dependent manner with an IC₅₀ value of 1.3 ± 0.2 µm , similar to the positive control, baicalin, with a POP IC₅₀ of 12 ± 3 µm . Copyright © 2012 John Wiley & Sons, Ltd.     

Angiotensin‐Converting Enzyme Inhibitory Activity and Antioxidant Properties of Nepeta crassifolia Boiss & Buhse and Nepeta binaludensis Jamzad

This article reports phytochemical and biological studies on Nepeta binaludensis and Nepeta crassifolia. Both species were investigated for their angiotensin‐converting enzyme (ACE) inhibitory activity and antioxidant properties through three in vitro models [2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) assay]. Aerial parts were extracted with methanol and partitioned between water and subsequently n‐hexane, ethyl acetate and n‐butanol. N. binaludensis methanol extract exerted significantly higher reducing power (1.9 μM Fe(II)/g) than did the positive control butylhydroxytoluene (63.2 μM Fe(II)/g) in FRAP assay. The highest DPPH radical scavenging activity was found for N. crassifolia, with IC₅₀ values of 9.6 and 12.1 µg/mL for ethyl acetate and n‐butanol fractions, respectively. n‐Butanol fraction of both species showed the highest ACE inhibitory activity, with IC₅₀ values of 59.3 and 81.7 µg/mL for N. binaludensis and N. crassifolia, respectively. Phytochemical investigations resulted in the isolation of ursolic acid, oleanolic acid, apigenin, luteolin and ixoroside. Apigenin‐7‐O‐glucoside, 8‐hydroxycirsimaritin and cirsimaritin were furthermore identified in N. crassifolia ethyl acetate‐soluble fraction. Nepetanudoside B was isolated from the n‐butanol fraction of N. binaludensis. Copyright © 2012 John Wiley & Sons, Ltd.     

In Vitro activities of plant extracts from Saudi Arabia against malaria,leishmaniasis, sleeping sickness and Chagas disease

The in vitro activity of the methanol extracts of 51 plants randomly collected from the Kingdom of Saudi Arabia and some of their fractions (petroleum ether, chloroform, ethyl acetate and aqueous) were evaluated against Plasmodium falciparum, Trypanosoma brucei brucei, T. cruzi and Leishmania infantum, as well as toxicity against MRC‐5 fibroblast cells. Ten crude methanolic extracts that demonstrated potent and adequately selective antiprotozoal activity were subjected to solvent fractionation using petroleum ether, ethyl acetate and chloroform. Only three samples showed promising antiprotozoal activity. Argemone ochroleuca (CHCl₃ fraction) showed pronounced activity against P. falciparum_GHA (IC₅₀ 0.32 μg/mL) and T. cruzi (IC₅₀ 0.30 μg/mL) with low cytotoxicity against MRC‐5 cells (CC₅₀ 11.6 μg/mL). Capparis spinosa (EtOAc fraction) showed pronounced activity against P. falciparum_GHA with an IC₅₀ 0.50 μg/mL in the absence of toxicity against MRC‐5 cell line (CC₅₀ > 30 μg/mL). Heliotropium curassavicum (CHCl₃ fraction) showed similar activity against P. falciparum (IC₅₀ 0.65 μg/mL; MRC‐5 CC₅₀ > 30 μg /mL). These three extracts will be subjected for further extensive studies to isolate and identify their active constituents. Copyright © 2010 John Wiley & Sons, Ltd.     

Medicinal Plants Traditionally Used for Treatment of Obesity and Diabetes Mellitus – Screening for Pancreatic Lipase and α‐Amylase Inhibition

In order to find new pancreatic lipase (PL) and α‐amylase inhibitors from natural sources for the treatment of obesity and related diseases as diabetes mellitus II, 23 medicinal plants with weight‐reducing, serum glucose‐reducing or related potential were investigated. Methanolic and water extracts of the plants were evaluated by using two in vitro test systems. Our findings have shown that the methanolic extract of Hibiscus sabdariffa L. (Malvaceae) showed high inhibitory activities to PL (IC₅₀: 35.8 ± 0.8 µg/mL) and α‐amylase (IC₅₀: 29.3 ± 0.5 µg/mL). Furthermore, the methanolic extract of Tamarindus indica L. (Leguminosae) showed a high anti‐lipase (IC₅₀: 152.0 ± 7.0 µg/mL) and the aqueous extract a high anti‐amylase (IC₅₀: 139.4 ± 9.0 µg/mL) activity. This work provides a priority list of interesting plants for further study with respect to the treatment of obesity and associated diseases. Copyright © 2015 John Wiley & Sons, Ltd.     

Evaluation of the antiprotozoal activity of neo‐clerodane type diterpenes from Salvia polystachya against Entamoeba histolytica and Giardia lamblia

Chia (Salvia polystachya Ort., Lamiaceae) is frequently used in Mexican traditional medicine to treat dysentery. In this study the main neo‐clerodane diterpenes (polystachynes A, B and D, as well as linearolactone) were isolated from the aerial parts of chia, and their antiprotozoal activities toward Entamoeba histolytica and Giardia lamblia trophozoites were evaluated in vitro. Linearolactone was the most potent antiamoebic and antigiardial compound with IC₅₀ values of 22.9 μM for E. histolytica and 28.2 μM for G. lamblia. Polystachynes A, B and D, showed moderate antiprotozoal activity against both protozoans with IC₅₀ values ranging from 117.0 to 160.6 μM for E. histolytica and from 107.5 to 134.7 μM for G. lamblia. These data suggest that linearolactone may play an important role in the antidiarrhoeal activity of S. polystachya. Copyright © 2009 John Wiley & Sons, Ltd.     

Cycloartane triterpenoids from Cimicifuga yunnanensis induce apoptosis of breast cancer cells (MCF7) via p53‐dependent mitochondrial signaling pathway

The present study was carried out to investigate the antitumor activity of five cycloartane triterpenoids isolated from Cimicifuga yunnanensis on the breast cancer cell line MCF7 and its corresponding drug resistant subline R‐MCF7, including cimigenol‐3‐O‐β‐d ‐xylopyranoside (compound 1), 25‐O‐acetylcimigenol‐3‐O‐β‐d ‐xylopyranoside (compound 2), 25‐chlorodeoxycimigenol‐3‐O‐β‐d ‐xylopyranoside (compound 3), 25‐O‐acetylcimigenol‐3‐O‐α‐l ‐arabinopyranoside (compound 4) and 23‐O‐acetylcimigenol‐3‐O‐β‐d ‐xylopyranoside (compound 5). The results showed that compounds 2–5 have relatively high antitumor activity on both MCF7 and R‐MCF7 cells. The involvement of apoptosis as a major cause of cycloartane triterpenoids‐induced cell death was further confirmed. The results of RT‐PCR showed that compounds 2–5 increased the expression of p53 and bax, which led to the loss of mitochondrial potential and then resulted in the activation of caspase‐7. These findings collectively demonstrated that compounds 2–5 induced apoptosis of MCF7 via p53‐dependent mitochondrial pathway. Copyright © 2010 John Wiley & Sons, Ltd.     

Antiprotozoal,antimycobacterial and cytotoxic potential of some british green algae

In the continuation of our search for natural sources for antiprotozoal and antitubercular molecules, we have screened the crude extracts of four green marine algae (Cladophora rupestris, Codium fragile ssp. tomentosoides, Ulva intestinalis and Ulva lactuca) collected from the Dorset area of England. Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Mycobacterium tuberculosis were used as test organisms in the in vitro assays. The selective toxicity of the extracts was also determined toward mammalian skeletal myoblast (L6) cells. The crude seaweed extracts had no activity against M. tuberculosis, but showed antiprotozoal activity against at least two protozoan species. All algal extracts were active against T. brucei rhodesiense, with C. rupestris being the most potent one (IC₅₀ value 3.7 μg/ml), whilst only C. rupestris and U. lactuca had moderate trypanocidal activity against T. cruzi (IC₅₀ values 80.8 and 34.9 μg/ml). Again, all four extracts showed leishmanicidal activity with IC₅₀ values ranging between 12.0 and 20.2 μg/ml. None of the extracts showed cytotoxicity toward L6 cells, indicating that their antiprotozoal activity is specific. This is the first study reporting antiprotozoal and antimycobacterial activity of British marine algae. Copyright © 2009 John Wiley & Sons, Ltd.     

Cyclooxygenase‐2 inhibitory and antioxidant compounds from the truffle Elaphomyces granulatus

The ethanol extract of fruiting bodies of Elaphomyces granulatus, a truffle‐like fungus, was evaluated for cyclooxygenase‐2 (COX‐2) enzyme inhibitory and antioxidant activities. Inhibition of COX‐2 activity was evaluated in mouse macrophages (RAW 264.7). The extract of E. granulatus caused a 68% inhibition of COX‐2 activity at 50 µg/mL. Bioassay‐guided investigation led to the isolation and identification of two active compounds, syringaldehyde and syringic acid. Syringaldehyde moderately inhibited COX‐2 activity with an IC₅₀ of 3.5 µg/mL, while syringic acid strongly inhibited COX‐2 activity with an IC₅₀ of 0.4 µg/mL. The antioxidant activity of the extract and isolated compounds was evaluated in HL‐60 cells by the DCFH‐DA method. The extract of E. granulatus showed a potent antioxidant effect, with an IC₅₀ of 41 µg/mL. Of the pure compounds, syringic acid displayed a strong antioxidant activity, with an IC₅₀ of 0.7 µg/mL, while syringaldehyde showed no activity in the assay. Copyright © 2008 John Wiley & Sons, Ltd.     

Antiproliferative effect of flavonoids and sesquiterpenoids from Achillea millefolium s.l. on cultured human tumour cell lines

The antiproliferative activities of n‐hexane, chloroform, aqueous‐methanol and aqueous extracts of the aerial parts of the Achillea millefolium aggregate on three human tumour cell lines were investigated by means of MTT assays. The chloroform‐soluble extract exerted high tumour cell proliferation inhibitory activities on HeLa and MCF‐7 cells, and a moderate effect on A431 cells; accordingly, it was subjected to detailed bioactivity‐guided fractionation. As a result of the multistep chromatographic purifications (VLC, CPC, PLC, gel filtration), five flavonoids (apigenin, luteolin, centaureidin, casticin and artemetin) and five sesquiterpenoids (paulitin, isopaulitin, psilostachyin C, desacetylmatricarin and sintenin) were isolated and identified by spectroscopic methods. The antiproliferative assay demonstrated that centaureidin is the most effective constituent of the aerial parts of yarrow: high cell growth inhibitory activities were observed especially on HeLa (IC₅₀ 0.0819 µm ) and MCF‐7 (IC₅₀ 0.1250 µm ) cells. Casticin and paulitin were also highly effective against all three tumour cell lines (IC₅₀ 1.286–4.76 µm ), while apigenin, luteolin and isopaulitin proved to be moderately active (IC₅₀ 6.95–32.88 µm ). Artemetin, psilostachyin C, desacetylmatricarin and sintenin did not display antiproliferative effects against these cell lines. This is the first report on the occurrence of seco‐pseudoguaianolides (paulitin, isopaulitin and psilostachyin C) in the Achillea genus. Copyright © 2008 John Wiley & Sons, Ltd.     

Antiparasitic,nematicidal and antifouling constituents from Juniperus berries

A bioassay‐guided fractionation of Juniperus procera berries yielded antiparasitic, nematicidal and antifouling constituents, including a wide range of known abietane, pimarane and labdane diterpenes. Among these, abieta‐7,13‐diene (1) demonstrated in vitro antimalarial activity against Plasmodium falciparum D6 and W2 strains (IC₅₀ = 1.9 and 2.0 µg/mL, respectively), while totarol (6), ferruginol (7) and 7β‐hydroxyabieta‐8,13‐diene‐11,12‐dione (8) inhibited Leishmania donovani promastigotes with IC₅₀ values of 3.5–4.6 µg/mL. In addition, totarol demonstrated nematicidal and antifouling activities against Caenorhabditis elegans and Artemia salina at a concentration of 80 µg/mL and 1 µg/mL, respectively. The resinous exudate of J. virginiana afforded known antibacterial E‐communic acid (4) and 4‐epi‐abietic acid (5), while the volatile oil from its trunk wood revealed large quantities of cedrol (9). Using GC/MS, the two known abietanes totarol (6) and ferruginol (7) were identified from the berries of J. procera, J. excelsa and J. phoenicea. Copyright © 2008 John Wiley & Sons, Ltd.     

Tyrosinase inhibitory constituents from the stems of Maackia fauriei

Bioassay‐guided investigation of the stems of Maackia fauriei led to the isolation of seven flavonoid constituents, formononetin (1), genistein (2), daidzein (3), texasin (4), tectorigenin (5), odoratin (6) and mirkoin (7). Their structures were elucidated on the basis of spectral studies as well as by comparison with literature data. Tyrosinase inhibition activities were carried out on the isolated compounds. Among these, mirkoin (7) was identified as a potent tyrosinase inhibitor. It inhibited mushroom tyrosinase with an IC₅₀ value of 0.005 mm , which is ten times more active than kojic acid (IC₅₀ = 0.045 mm ). The inhibition kinetics, analysed by Lineweaver‐Burk plots, indicated mirkoin (7) to be a competitive inhibitor of tyrosinase when l ‐tyrosinase was used as a substrate. The results suggest that hydroxyl groups at C‐4′ in the B ring of flavonoids play an important role in the tyrosinase inhibition activities. Interestingly, compounds 4–7 were isolated for the first time from this plant. Copyright © 2009 John Wiley & Sons, Ltd.     

Xanthine Oxidase Inhibitory Activity of Hungarian Wild‐Growing Mushrooms

Mushrooms represent a remarkable and yet largely unexplored source of new, biologically active natural products. In this work, we report on the xanthine oxidase (XO) inhibitory activity of 47 wild‐growing mushrooms native to Hungary. Aqueous and organic (n‐hexane, chloroform, and 50% methanol) extracts of selected mushrooms from different families were screened for their XO inhibitory activities. Among the 188 extracts investigated, the chloroform and 50% methanol fractions proved to be the most effective. Some species exhibited high inhibitory activity, e.g., Hypholoma fasciculare (IC₅₀ = 67.76 ± 11.05 µg/mL), Suillus grevillei (IC₅₀ = 13.28 ± 1.58 µg/mL), and Tricholoma populinum (IC₅₀ = 85.08 ± 15.02 µg/mL); others demonstrated moderate or weak activity. Additional studies are warranted to characterize the compounds responsible for the XO inhibitory activity of mushroom extracts. Copyright © 2014 John Wiley & Sons, Ltd.     

新疆鼠尾草总酚酸的体外抗氧化活性

目的：研究新疆鼠尾草总酚酸提取物和纯化物的体外抗氧化活性。方法：以40%乙醇提取和大孔吸附树脂纯化分别制备得到新疆鼠尾草总酚酸的提取物和纯化物,以维生素C（VC）为对照,通过体外化学模拟方法测定新疆鼠尾草总酚酸提取物和纯化物的还原能力、对·DPPH自由基、羟基自由基（·OH）和超氧自由基（O₂^-·）的清除能力,研究新疆鼠尾草总酚酸的抗氧化活性。结果：新疆鼠尾草总酚酸提取物和纯化物清除·DPPH自由基的作用50%清除浓度（IC₅₀,分别为0.029,0.039 g·L^-1）弱于VC（IC₅₀0.018 g·L^-1）;对羟基自由基（·OH）的清除作用（IC₅₀分别为0.212,0.165 g·L^-1）强于VC（IC₅₀0.356 g·L^-1）;对超氧自由基（O₂^-·）的清除能力（IC₅₀分别为3.735,1.913 g·L^-1）弱于VC（IC₅₀0.390 g·L^-1）,其纯化物还具有一定的还原能力。结论：新疆鼠尾草总酚酸具有较强的抗氧化作用。