翁布中酚性化合物体外抗氧化活性的研究

目的 研究藏药翁布中13种酚性化合物的体外抗氧化活性.方法 采用DPPH自由基清除活性试验、FRAP法、ABTS法和酪氨酸酶活性抑制法评价13种酚性化合物的自由基清除能力及抗氧化活性.结果 没食子酸、3,5-二羟基-4-甲氧基苯甲酸清除DPPH自由基的半数抑制浓度(IC50)低于维生素C;FRAP法测定结果中,化合物阿魏酸、阿魏酸葡糖苷、咖啡酸、对羟基桂皮酸、没食子酸、3,5-二羟基-4-甲氧基苯甲酸的总抗氧化值均高于阳性对照Trolox;ABTS法测定结果中,化合物阿魏酸、松柏醇、阿魏酸葡糖苷、咖啡酸、对羟基桂皮酸、没食子酸、4-羟基-α-甲基苯丙醇、4-羟基-3-甲氧基苯甲酸的总抗氧化值相对于Trolox标准溶液均大于0.01 mmol· L-1;13种酚性化合物对酪氨酸酶均具抑制活性,但IC50均高于阳性对照曲酸.结论 阿魏酸、阿魏酸葡糖苷、咖啡酸、对羟基桂皮酸、没食子酸、3,5-二羟基-4-甲氧基苯甲酸具有较强的抗氧化活性.     

何首乌及首乌藤抗氧化活性研究

目的评价何首乌和首乌藤体外总抗氧化活性。方法采用清除二苯代苦味酰基（DPPH）自由基、清除〔2,2′-连氨-（3-乙基苯并噻唑啉-6-磺酸）二氨盐〕（ABTS）自由基和铁离子还原/抗氧化能力（FRAP）测定法。结果将测定结果与水溶性维生素E（6-羟基-2,5,7,8-四甲基苯并二氢吡喃-2-羧酸,Trolox）及阳性对照二丁基羟基甲苯（BHT）进行比较,发现何首乌的乙酸乙酯和甲醇提取物具有较强的清除DPPH自由基、清除ABTS自由基及还原Fe3＋的能力。结论何首乌的总的抗氧化活性好于首乌藤。在6种提取物中,何首乌的乙酸乙酯提取物抗氧化能力最强。同一药用部位,甲醇和乙酸乙酯提取物的抗氧化活性好于石油醚提取物。3种方法之间有很好的相关性,以DPPH法与ABTS法相关性最好（R=0.996）。     

藜芦的黄酮类化学成分研究

目的:对百合科藜芦属植物藜芦Veratrum nigrumL.的黄酮类化学成分进行分离和结构鉴定。方法:采用溶剂法、硅胶柱层析、Sephadex LH-20柱层析进行成分分离和纯化,通过理化性质和波谱技术鉴定化合物的结构。结果:从藜芦乙醇提取物中分离鉴定了9个黄酮类化合物,分别鉴定为3-甲氧基异鼠李素(3-methoxylisorhamnetin,1)、异鼠李素(isorham-netin,2)、3-甲氧基槲皮素(3-methoxylquercetin,3)、槲皮素(quercetin,4)、异槲皮苷(isoquercitrin,5)、3,5,7-三羟基-3′,5′-二甲氧基黄酮(3,5,7-trihydroxy-3′,5-′dimethoxylflavone,6)、5,7,4′-三羟基-3′-甲氧基黄酮(5,7,4-′trihydroxy-3-′methoxyl-fla-vone,7)、5,7,3′,4′-四羟基黄酮(5,7,3′,4-t′etrahydroxyflavone,8)、5,7,3′,5′-四羟基黄酮(5,7,3′,5-′tetrahydroxyflavone,9)。结论:化合物1~9均为首次从该植物中分离得到。     

金盏银盘黄酮类成分抗氧化研究

目的测定金盏银盘黄酮类成分抗氧化活性。方法采用Fenton反应法,分别检测金盏银盘不同部位及黄酮单体的抗氧化活性。结果乙酸乙酯部位的羟自由基清除率最高;乙酸乙酯部位分离得到的黄酮单体,Z-6-O-(6″-丙酰基-β-D-吡喃葡萄糖基)-6,7,3',4'-四羟基橙酮的抗氧化效果优于槲皮素。结论金盏银盘黄酮对羟自由基有较好的清除作用。     

化合物3,4,5-三羟基-N-[2-(4-羟基苯基)乙基]苯甲酰胺的抗氧化活性

目的对化合物3,4,5-三羟基-N-[2-(4-羟基苯基)乙基]苯甲酰胺(3,4,5-trihydroxy-N-[2-(4-hydroxyphenyl)ethyl]-benzamide,THHEB)的抗氧化活性进行研究。方法通过测定对有机自由基1,1-二苯基苦基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)的清除能力、6-羟基-2,5,7,8-四甲基苯并二氢吡喃-2-羧酸(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid,Trolox)当量抗氧化能力(trolox-equivalent antioxidant capacity assay,TEAC),测定超氧自由基的清除活性实验、脂质过氧化法以及羟基自由基诱导DNA损伤的方法评价THHEB的抗氧化活性。结果5种方法检测结果均显示,THHEB具有很强的清除自由基的活性。其中,THHEB对稳定自由基DPPH和超氧自由基的清除能力超过抗坏血酸的相应活性,其IC50值分别为22.8、2.5μmol.L-1。用TEAC方法测定THHEB总的抗氧化能力大约为0.6,也比L-抗坏血酸相应值高。脂质过氧化法测定的THHEB活性要弱于著名的抗氧化化合物2,6-二叔基对甲苯酚(butylated hydroxytoluene,BHT)。此外,非常小浓度比如4μmo.lL-1的THHEB对羟基自由基导致的pBR322 DNA链断裂具有显著的保护作用。结论THHEB具有很强的清除自由基的活性。     

胡柚皮中化学成分的研究

目的:对胡柚皮中黄酮类成分进行研究.方法:采用硅胶柱色谱分离及重结晶的方法从胡柚皮中分离化合物,并根据理化性质和波谱数据进行化合物的结构鉴定.结果:分离并鉴定了五个黄酮类化合物,分别为:5-羟基-6,7,8,3',4'-五甲氧基黄酮(Ⅰ),5,6,7,8,4'-五甲氧基黄酮(Ⅱ),5,6,7,8,3',4'-六甲氧基黄酮(Ⅲ),5,6,7,3',4'-五甲氧基黄酮(Ⅳ),5-羟基-3,6,7,8,3',4'-六甲氧基黄酮(Ⅴ),结论:从该植物中分离鉴定了五个黄酮类化合物.     

穿心莲根的化学成分研究

为研究常用中药爵床科植物穿心莲(Andrographis paniculata)根的化学成分,运用各种色谱方法从安徽临泉产穿心莲根的80%乙醇提取物中分离并鉴定了28个化合物,其中20个黄酮:5,5'-二羟基-7,8,2'-三甲氧基黄酮(1)、5-羟基-7,8,2',6'-四甲氧基黄酮(2)、5,3'-dihydroxy-7,8,4',-trimethoxyflavone(3)、2'-羟基-5,7,8-三甲氧基黄酮(4)、5-羟基-7,8,2',3',4'-五甲氧基黄酮(6)、wightin(7)、5,2',6'-trihydroxy-7-methoxyflavone 2'-O-β-D-glucopyranoside(8)、5,7,8,2'-四甲氧基黄酮(10)、5-羟基-7,8-二甲氧基二氢黄酮(11)、5-羟基-7,8-二甲氧基黄酮(12)、5,2'-二羟基-7,8-二甲氧基黄酮(13)、5-羟基-7,8,2',5'-四甲氧基黄酮(14)、5-羟基-7,8,2',3'-四甲氧基黄酮(15)、5-羟基-7,8,2'-三甲氧基黄酮(16)、5,4'-二羟基-7,8,2',3'-四甲氧基黄酮(17)、二氢黄芩新...     

低聚甘露糖醛酸磷酸酯的制备及其抗氧化活性探究△

目的 旨在探究不同取代度的低聚甘露糖醛酸磷酸酯的体外抗氧化活性。方法 采用磷酸-脲素法制备了3种不同取代度的磷酸化衍生物,然后测定了三种磷酸化多糖的体外抗氧化活性,包括清除超氧自由基、1,1-二苯基-2-吡啶酰肼(DPPH)自由基、羟基自由基及还原能力。结果 通过控制磷酸用量,制备了三种含磷量为3.90%、5.14%和6.56% 的单磷酸酯衍生物;与原料相比,低聚甘露糖醛酸磷酸酯衍生物的抗氧化活性增强;并且随着磷含量的增加,磷酸酯衍生物的羟基自由基、DPPH自由基清除活性及还原力也增强。结论 适当的磷酸化修饰可以显著提高低聚甘露糖醛酸的体外抗氧化活性,为海洋多糖的应用开发提供了借鉴。     

差不嘎蒿化学成分的分离与鉴定

目的研究差不嘎蒿的化学成分。方法利用硅胶柱色谱、葡聚糖凝胶等方法对差不嘎蒿的化学成分进行分离纯化,根据其理化性质和波谱数据鉴定化合物的结构。结果从差不嘎蒿中分离得到10个化合物,分别为5-羟基-7,4'-二甲氧基二氢黄酮(5-hydroxy-7,4'-dimethoxyflavanone,1)、3,5-二羟基-7,4'-二甲氧基二氢黄酮(3,5-dihydroxy-7,4'-dimethoxyflavanone,2)、异野樱素(isosakuranetin,3)、7-羟基-5,6-二甲氧基香豆素(umckalin,4)、5,7-二羟基-3,3',4'-三甲氧基黄酮(5,7-dihydroxy-3,3',4'-trimethoxyflavone,5)、5-羟基-6,7-二甲氧基香豆素(tomentin,6)、山奈酚-4'-O-甲醚(Kaempferol-4'-O-methylether,7)、泽兰黄素(eupatrin,8)、β-谷甾醇(β-sitosterol,9)、二氢槲皮素-4'-甲醚(taxifolin-4'-methylether,10)。结论化合物4、5、7、8、10为首次从该属植物中分离得到。     

显脉羊蹄甲的生物活性成分

目的对显脉羊蹄甲中具有抑制血小板聚集活性的有效部位的化学成分进行研究。方法从显脉羊蹄甲抑制血小板聚集活性部位中,利用溶剂分步萃取法和各种色谱手段(硅胶吸附柱色谱,聚酰胺柱色谱,Sephadex LH-20柱色谱,开放ODS柱色谱,液相色谱等)分离得到了10个化合物,根据其理化性质和光谱数据分析(1H-NMR、13C-NMR等)鉴定了它们的结构。结果从活性部位中分离鉴定的化合物为黄酮类,分别是:3,5,7,4'-四羟基-3'-甲氧基黄酮(3,5,7,4'-tetrahydroxy-3'-methoxyflavone,1)、5,7,3',4'-四羟基-3-甲氧基黄酮(5,7,3',4'-tetrahydroxy-3-methoxyflavone,2)、槲皮素(quercetin,3)、木樨草素(luteolin,4)、山柰酚(kaempferol,5)、5,7,4'-三羟基-3'-甲氧基黄酮(5,7,4'-trihydroxy-3'-methoxyflavone,6)、7,3',4'-三羟基-3-甲氧基黄酮(7,3',4'-trihydroxy-3-methoxyflavone,7)、杨梅苷(myricitrin,8)、槲皮素-3-O-α-L-吡喃阿拉伯糖苷(quercetin-3-O-α-Larabinopyranoside,9)、儿茶素(catechin,10)。结论化合物1-6、8-9均为首次从该植物中分离得到,化合物7为首次从羊蹄甲属植物中分离得到。     

Pharmacological study on piperine

Systematic pharmacological studies on piperine have revealed that this compound elicited diverse pharmacological activities; CNS depressant activity characterized by antagonism against electroshock seizure and by muscle relaxant activity in mice; antipyretic activity in typhoid vaccinated rabbits; analgesic activity as evaluated by tail-clip pressure and writhing syndrome in mice; antiinflammatory activity in carrageenin-induced edema in rats.     

Synthesis of new thiazolylthiazolidinylbenzothiazoles and thiazolylazetidinylbenzothiazoles as potential insecticidal, antifungal, and antibacterial agents

A series of 2-{[2'-(3'-chloro-2'-oxo-4'-substitutedaryl-1'-azetidinyl)-1',3'-thiazol-4'-yl] thio}benzothiazoles (4a-4e) and 2-{[(2'-(2'-substitutedaryl-4'-thiazolidinon-3'-yl)-1',3'-thiazol-4'-yl]thio}benzothiazoles (5a-5e) have been synthesized from 2-[(2'-substitutedarylidenylimino-1',3'-thiazol-4'-yl)thio]benzothiazoles (3a-3e). The structure of these compounds has been elucidated by elemental (C, H, N) and spectral (IR, (1)H-NMR, Mass) analysis. Furthermore, compounds 3a-3e, 4a-4e, and 5a-5e were screened for insecticidal activity against Periplaneta americana and antifungal, antibacterial activities in vitro against different strains of fungi and bacteria. Out of the fifteen compounds tested, compound 5b, 2-{[2'-(2'-p-hydroxy-m-methoxyphenyl)-4'-thiazolidinon-3'-yl)-1',3'-thiazol-4'-yl]thio}benzothiazole, was found to possess most prominent insecticidal activity.     

Juniperus oxycedrus L. subsp. oxycedrus and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. “berries” from Turkey: Comparative evaluation of phenolic profile,antioxidant, cytotoxic and antimicrobial activities

This work aimed to evaluate and compare the phenolic profile and some biological properties of the ripe “berries” methanol extracts of Juniperus oxycedrus L. subsp. oxycedrus (Joo) and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom) from Turkey. The total phenolic content resulted about 3-fold higher in Jom (17.89 ± 0.23 mg GAE/g extract) than in Joo (5.14 ± 0.06 mg GAE/g extract). The HPLC–DAD–ESI–MS analysis revealed a similar flavonoid fingerprint in Joo and Jom, whereas a difference in their quantitative content was found (4632 μg/g extract and 12644 μg/g extract). In addition, three phenolic acids were detected in Jom only (5765 μg/g extract), and protocatechuic acid was the most abundant one. The antioxidant capacity of the extracts was evaluated by different in vitro assays: in the DPPH and in the TBA tests a stronger activity in Jom was highlighted, while Joo exhibited higher reducing power and metal chelating activity. Joo and Jom did not affect HepG2 cell viability and both extracts resulted virtually non-toxic against Artemia salina. The extracts were also studied for their antimicrobial potential, displaying efficacy against Gram-positive bacteria.     

Structure-antibacterial,antitumor and hemolytic activity relationships of cecropin A-magainin 2 and cecropin A-melittin hybrid peptides

In order to elucidate the structure-antibiotic activity relationship of cecropin A-magainin 2 and cecropin A-melittin hybrid peptides, several truncated peptides and the analogues with amino acid substitutions were synthesized and their antibacterial, antitumor and hemolytic activities of were examined. Cecropin A-magainin 2 hybrid analog, L¹⁶-CA(1–8)-MA(1–12) (termed as L-CA-MA in this study: KWKLFKKIGIGKFLHLAKKF-NH₂), is known to have potent antibacterial and antitumor activity with less hemolytic activity. We found that the C-terminal region of L-CA-MA is more involved in the α-helical structure on cell membrane-like environment than N-terminal one by circular dichroism analysis. Deletion of the Gly-lle-Gly sequence, the central hinge region of L-CA-MA, produced a considerable reduction in antitumor and hemolytic activity rather than an antibacterial one. The insertion of Pro, Gly-lle or Gly-Pro in this hinge region of L-CA-MA caused retention of both antibacterial and antitumor activity while causing a significant decrease in hemolytic activity. However, the substitution with Gly-Pro-Gly instead of the Gly-lle-Gly in CA(1–8)-MA(1–12), CA(1–8)-ME(1–12), CA(1–13)-MA(1–13) and CA(1–13)-ME(1–13) hybrids resulted in a drastic decrease in antibacterial, antitumor and hemolytic activity. The increase of hydrophobicity at position 16 in CA(1–8)-MA(1–12) by substituting Trp or Phe induced a significant increase in hemolytic activity without a considerable change in either antibacterial or antitumor activity. Therefore, these results suggested that the appropriate flexibility in the hinge region of CA-MA and CA-ME hybrid peptides and the appropriate hydrophobicity at position 16 in the hydrophobic region of CA (1–8)-MA(1–12) are important in potent antibacterial and antitumor activity with no hemolytic effect.     

Antimicrobial activity of 5-arylidene aromatic derivatives of hydantoin. Part 2

Various 5-chloroarylidene-2-amino substituted derivatives of imidazoline-4-one were synthesized and evaluated for their activity in vitro against Mycobacterium tuberculosis and other type strains of bacteria and fungi. 2-Chloro- and 2,4-dichlorobenzylidene substituted hydantoins exhibited antimycobacterial effect. The most potent compounds 3i, 3j, 3o, 3q and 3s were classified for further tests. The antimitotic effect of the investigated hydantoins was also examined.     

Antinociceptive,anti-inflammatory,and antioxidant properties of Phoradendron piperoides leaves

Phoradendron piperoides (Kunth) Trel. (Viscaceae) is a parasitic plant widely distributed in regions of the Brazilian northeast. Different species of Phoradendron are used in folk medicine for the treatment of cough, influenza, gastrointestinal and female disorders, and pain. In order to evaluate the actions of this plant, studies were performed on antinociceptive, anti-inflammatory, and antioxidant activities. The methanol extract (ME) and dichloromethane, ethyl acetate, and methanol partitions of P. piperoides leaves were used in the following experiments. Oral treatment with the ME elicited inhibitory activity (p?<?0.01) on the acetic acid effect at 100 (32.08%), 200 (34.46%), and 400?mg/kg (49.50%). P. piperoides ME reduced the formalin effect at the second phase (200 and 400?mg/kg, p?<?0.05); however, the ME did not elicit any inhibitory effect on the hot-plate test. Edema formation induced by carrageenan was reduced (p?<?0.05) with the ME by 28% (200?mg/kg) and 33% (400?mg/kg). ME, dichloromethane, ethyl acetate, and methanol partitions reacted with the DPPH radical and reduced the DPPH radical by 94.5, 37.2, 77.2, and 95.7%, respectively. ME, ethyl acetate, and methanol partitions exhibited low IC₅₀ values.     

Anti-inflammatory,Antinociceptive, and Neuropharmacological Activities of Clerodendron viscosum.

Abstract

The crude methanol extract of Clerodendron viscosum. Vent. (Verbenaceae) leaves was evaluated for its anti-inflammatory, antinociceptive, and neuropharmacological activities. When given orally to rats at doses of 200 and 400 mg/kg of body weight, the extract showed a significant (p < 0.001) anti-inflammatory activity against carrageenan-induced rat paw edema comparable with the standard drug phenylbutazone at the dose of 100 mg/kg of body weight. It also produced a significant writhing inhibition in acetic acid–induced writhing in mice at the oral dose of 250 and 500 mg/kg of body weight (p < 0.001), which was comparable with the standard drug diclofenac sodium at the dose of 25 mg/kg of body weight. Moreover, when given intraperitoneally to albino mice, it potentiated the pentobarbital-induced sleeping time (p < 0.001), decreased the open field score in open field test (p < 0.001), decreased the number of holes crossed from one chamber to the other in the hole-cross test (p < 0.001), and decreased the head dip responses in the hole-board test (p < 0.001) at the dose of 250 and 500 mg/kg of body weight. The overall results tend to suggest the anti-inflammatory, antinociceptive, and central nervous system depressant activities of the crude methanol extract of Clerodendron viscosum..     

Hemorrhagic activity of the Duvernoy''s gland secretion of the xenodontine colubrid Philodryas patagoniensis from the north-east region of Argentina

Colubrid snakes belonging to Philodryas genus, widespread all over South America, bring about lesions (swelling, ecchymosis, transient bleeding from the bite site punctures), that are similar to those produced by Bothrops species (yarará). In the present work we began the characterization of Philodryas patagoniensis venom. We examined if this venom produces hemorrhagic lesions as those observed in victims bitten by Philodryas olfersii. Hemorrhagic, proteolytic and fibrinogenolytic activities were evaluated, and histological observations in samples of gastrocnemius muscle were carried out. Inhibition studies were carried out in metal chelator (ethylenediaminetetraacetic acid) presence. Our results show a small Minimum Hemorrhagic Dose (MHD=0.035 μg) and a high proteolytic activity (143 U/mg), and prove the capacity of this venom to degrade fibrinogen in vitro rendering it unclottable by thrombin, supporting the presence of proteases, principally metalloproteases, in P. patagoniensis venom that are able to alterate the vascular wall and degrade fibrinogen, being both activities responsible of a high hemorrhagic activity.     

New thiazolyl-pyrazoline derivatives bearing nitrogen mustard as potential antimicrobial and antiprotozoal agents

A new series of N-substituted pyrazoline derivatives 6a–g , 7a–g , 8a–g , and 9a–g was synthetized by reaction of hydrazine derivatives and chalcone–thiazole hybrids bearing nitrogen mustard 5a–g . The chalcones 5a–g were obtained by Claisen–Schmidt condensation of thiazole-2-nitrogen mustard 3 and selected acetophenones 4a–g . These new compounds 6/7/8/9a–g were screened for their antifungal activity against Cryptococcus neoformans, with IC₅₀ values of 3.9–7.8 µg/ml for the N-3,5-dichlorophenyl pyrazolines 9e – g . Interestingly, those compounds show low cytotoxic effects toward erythrocytes (RBC). In addition, N-acetyl ( 6a,b ) and N-formyl pyrazolines ( 7a , 7b , 7c , and 7g ) showed inhibitory activity against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, and vancomycin-intermediate S. aureus, with the most important minimum inhibitory concentration values ranging from 31.25 to 125 µg/ml. Regarding the antiprotozoal activity, thiazolyl-pyrazolines 9g , 8f , and 7c display high activity against Plasmodium falciparum, Leishmania (V) panamensis, and Trypanosoma cruzi, with EC₅₀ values of 11.80, 6.46, and 4.98 μM, respectively, and with 7c being approximately 2.6-fold more potent than benznidazole with a selectivity index of 1.61 on U-937 human cells, showing promising potential as a novel antitrypanosomal agent.