青天葵4种提取物抗氧化活性与其总黄酮和总酚含量的相关性

目的考察青天葵Nervilia fordii(Hance)Schltr.氯仿、乙酸乙酯、正丁醇、乙醇提取物抗氧化活性与其总黄酮和总酚含有量的相关性。方法 Al Cl3-HAc-Na Ac显色法和福林-酚比色法分别测定青天葵4种提取物中总黄酮和总酚含有量,通过测定DPPH自由基清除能力、羟自由基清除能力、ABTS自由基清除能力、还原能力评价提取物抗氧化活性,SPSS17.0软件分析抗氧化活性与2种成分含有量的相关性。结果青天葵4种提取物的抗氧化活性均呈量效关系,乙酸乙酯提取物最强,而乙醇提取物最弱。其与总黄酮含有量有一定相关性(0.604r0.638),与总酚含有量相关性显著(r0.977)。结论青天葵乙酸乙酯提取物可用于天然抗氧化剂开发,总酚含有量是影响其抗氧化活性的主要因素。     

藏紫菀不同溶剂提取物的体外抗氧化活性

目的研究藏紫菀不同溶剂提取物的体外抗氧化活性。方法采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法、2,2′-联氮基双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(ABTS)自由基清除法、超氧阴离子自由基清除法、NO自由基清除法、羟自由基清除法及铁还原/抗氧化能力(FRAP)法,对藏紫菀70%乙醇粗提物、正己烷部位、乙酸乙酯部位、正丁醇部位、水提部位等极性部位的抗氧化活性进行评价,同时分析抗氧化活性与总多酚和总黄酮含量之间的关系。结果与粗提物相比,乙酸乙酯、正丁醇部位表现出更强的抗氧化活性,且抗氧化活性与总黄酮和总多酚的含量密切相关,乙酸乙酯、正丁醇部位中总多酚含量分别高达(311.09±7.92)、(320.21±10.69)mg没食子酸/g提取物,总黄酮含量最高可达(667.78±19.18)、(623.97±14.01)mg芦丁/g提取物。乙酸乙酯部位对DPPH、ABTS⁺·、·OH、O₂^-·均具有最高的自由基清除活性,而正丁醇部位的NO清除活性和FRAP值均高于其他部位。结论藏紫菀乙酸乙酯、正丁醇部位具有较强自由基清除能力,是活性优异的天然抗氧化剂,可将其用于天然抗氧化活性单体成分的提取和分离。     

萆薢总黄酮含量测定及其抗氧化活性研究

目的研究萆薢不同溶剂提取物的总黄酮含量及其抗氧化活性。方法用冷浸法得到萆薢乙醇、丙酮和乙酸乙酯提取物。测定了三种提取物的总黄酮含量,并通过测定其对DPPH自由基的清除能力和还原能力来研究其抗氧化能力。结果萆薢不同溶剂提取物均表现出很强的抗氧化性能,其中乙酸乙酯提取物具有最优异的抗氧化能力。结论萆薢提取物具有作为天然抗氧化剂进行开发的潜力。     

女贞子醇提物不同极性部位的体外抗氧化活性研究

目的:研究女贞子乙醇提取物不同极性部位的体外抗氧化活性,旨在为女贞子抗氧化相关有效成分的分离提供依据。方法:在体外化学模拟的条件下,采用1,1-二苯基-2-苦肼基(DPPH)自由基法、邻苯三酚法测定其对DPPH自由基和对超氧阴离子自由基的清除能力。结果:女贞子醇提物的石油醚、乙酸乙酯、正丁醇3个萃取部位抗氧化结果显示,相同浓度下女贞子乙酸乙酯部位抗氧化效果最强,其次是正丁醇部位、石油醚部位。结论:测定了女贞子醇提物不同溶剂提取物的抗氧化活性,初步确定女贞子中抗氧化相关活性成分主要存在于女贞子醇提物的乙酸乙酯部位。     

总抗氧化能力检测试剂盒(ABTS)法测定 江南星蕨的抗氧化活性

目的:研究江南星蕨不同溶剂提取物的抗氧化活性。方法:用冷浸法得到江南星蕨乙醇、丙酮和乙酸乙酯提取物,测定了3种提取物的总黄酮含量,并用总抗氧化能力检测试剂盒(ABTS)体系吸光值的变化研究它们的抗氧化能力。结果:3种提取物对ABTS.+自由基清除率均超过了80%,清除率最高可达96.11%。结论:江南星蕨不同溶剂提取物均表现出很强的抗氧化能力,有望作为天然抗氧化剂和功能性食品得到开发。     

22种藏药材抗氧化活性研究

目的:考察22种藏药材乙醇提取物抗氧化活性,对具有显著活性的药材进一步筛选其抗氧化活性部位。方法:取22种藏药材95%乙醇提取物,通过总抗氧化能力、抑制脂质氧化能力、清除羟基自由基能力、清除DPPH.能力四个体系筛选其抗氧化活性。对筛选到具有显著抗氧化活性的藏药材分别用石油醚、氯仿、乙酸乙酯和正丁醇萃取得到不同极性部位后,通过上述四个体系考察其抗氧化活性部位。结果:筛选到金缕梅、美丽棱子芹、岩白菜、塔黄、刚毛杜鹃、柳兰、蕨麻、普通鹿蹄草8种藏药材乙醇提取物具有显著抗氧化活性;对这8种药材的极性部位进行抗氧化活性筛选,其中尤以岩白菜的乙酸乙酯萃取物和柳兰的正丁醇萃取物活性最强。     

生、炒王不留行抗氧化活性的比较研究

目的：研究两种王不留行（Sapolzaria vaccaria L）种子提取物的抗氧化活性。方法：采用DPPH法分别测定王不留行与炒王不留行的乙醚、乙酸乙酯、正丁醇和水等不同极性溶剂提取物的抗氧化活性。结果：炒王不留行水提取部位、正丁醇提取部位、乙醚提取部位和乙酸乙酯提取部位的半数抑制浓度分别为0．50、0．15、0．0881和0．023mg／ml；王不留行水提取部位、正丁醇提取部位、乙醚提取部他和乙酸乙酯提取部位的半数抑制浓度分别为0．82、0.26、0.185和0．048mg/ml。炒王不留行的抗氧化活性大于王不留行；两种王小留仃乙酸乙酯提取物的抗氧化活性均最强，结论：王不留行与炒三不留行所含抗氧化成分存在一定的差异。     

狐狸尾不同极性溶剂提取物体外抗氧化活性研究

目的:研究狐狸尾Uraria lagopodioides不同极性提取部位的体外抗氧化活性。方法:以乙酸乙酯、丙酮和95%乙醇为溶剂分别对狐狸尾进行冷浸提取,得到各种溶剂提取物EAE,AE,EE,采用紫外分光光度法分别测定总黄酮含量,并将各提取物配制成0.2～1.2 g.L-1,采用ABTS.+法、DPPH.法和铁离子还原能力法测定不同浓度提取物抗氧化活性。结果:测得狐狸尾EAE,AE,EE总黄酮含量分别为74.0,65.7,84.2 g.kg-1;狐狸尾各提取部位具有较强ABTS.+,DPPH.清除能力及还原能力,其中乙醇提取部位(EE)具有优异的抗氧化能力,在3个体系中,其半清除浓度(IC50)分别为0.52,1.36,4.88 g.L-1。结论:狐狸尾各提取物具有作为天然抗氧化剂和功能性食品进行研究和开发的潜力。     

窝儿七不同提取物中总黄酮总酚含量及其抗氧化活性的研究

目的:研究窝儿七不同提取物的抗氧化活性与其总黄酮和总酚含量的相关性。方法:采用NaNO_2-Al(NO_3)_3-NaOH显色法和Folin-Ciocalteu比色法分别测定窝儿七药材5种提取物中总黄酮和总酚的含量,并用DDPH自由基清除能力、羟自由基清除能力、ABTS自由基清除能力、还原能力以及T-AOC总抗氧化能力方法,评价不同提取物的抗氧化活性。结果:正丁醇提取物中总黄酮含量最高,为45.62 mg/g,乙酸乙酯的总黄酮含量也较高,乙酸乙酯提取物中总酚含量最高,为106.05 mg/g。窝儿七的五种提取物的总黄酮、总酚含量与抗氧化活性有一定的相关性,其DDPH自由基清除能力为乙酸乙酯>正丁醇>70%乙醇>水>氯仿。ABTS自由基清除能力为乙酸乙酯>70%乙醇>正丁醇>氯仿>水。羟自由基清除能为乙酸乙酯>正丁醇>70%乙醇>氯仿>水。还原能力为乙酸乙酯>70%乙醇>氯仿>正丁醇>水。总抗氧化能力(T-AOC)为乙酸乙酯>正丁醇>70%乙醇>水>氯仿。结论:窝儿七的乙酸乙酯提取物最多,抗氧化活性最强,乙酸乙酯可作为抗氧化活性物质提取的最佳溶剂,为窝儿七综合开发提供实验依据,也为其抗氧化研究提供参考。     

DPPH法测定青皮加速溶剂萃取提取物的抗氧化活性

目的:研究海南特有药用植物青皮Vatica mangachapoi Blanco的抗氧化活性。方法:利用加速溶剂萃取技术(ASE)快速制备青皮石油醚(MSO)、乙酸乙酯(EtOAc)、乙醇(EtOH)、甲醇(MeOH)提取物;结合酶标仪,快速筛选具有清除二苯代苦味肼基自由基(DPPH.)能力的ASE提取物。结果:青皮不同溶剂ASE提取物清除DPPH.的能力大小为:乙酸乙酯ASE提取物>乙醇ASE提取物>石油醚ASE提取物>甲醇ASE提取物;其IC50值分别为0.143 4,0.501 8,0.567 7,0.693 7 g.L-1。乙酸乙酯ASE提取物的抗氧化活性强于抗坏血酸(IC50=0.203 4 g.L-1)。结论:乙酸乙酯ASE提取物具有较强清除DPPH.的能力,有望开发成天然的抗氧化剂。     

4种省沽油属植物总酚类物质抗氧化活性的研究

目的：比较省沽油属4种植物干燥叶片中不同提取部位总酚类物质含量及其抗氧化活性测定,为开发利用打下基础。方法：用70%乙醇提取各植物干燥叶片,浓缩得乙醇浸膏,并用系统溶剂萃取法得到乙酸乙酯和氯仿两个部位;然后采用改良的Folin-Ciocalteu比色法测定各植物各部位总酚类物质含量,并通过DPPH氧化自由基清除活性实验及抗过氧化亚硝酸盐硝化活性实验分析各总酚类物质抗氧化活性。结果：比色法结果表明,四种植物中乙酸乙酯部位总酚类物质含量均高于氯仿部位,其中省沽油干燥叶片乙酸乙酯部位总酚类物质含量最高,抗氧化活性最强。结论：省沽油属植物叶片中含有活性酚类物质,其中省沽油叶片乙酸乙酯部位含量最高,活性最强,值得进一步开发利用。     

太白乌头提取物抗氧化活性研究

目的研究太白乌头提取物的抗氧化活性。方法将太白乌头乙醇提取物采用溶剂萃取法，分成极性不同的五个部分，并采用DPPH法和邻苯三酚自氧化法测定各部分的清除DPPH·（二苯代苦味肼自由基）和·O2^-（超氧阴离子自由基）的能力，以测定其抗氧化活性，并和抗坏血酸进行比较。结果清除DPPH·能力大小为：抗坏血酸〉乙酸乙酯部分〉正丁醇部分〉石油醚部分〉水部分一氯仿部分，清除·O2^-的能力以石油醚部分、乙酸乙酯部分为好，其他部分认为无清除·O2^-的活性。结论太白乌头醇提物乙酸乙酯部分、正丁醇部分和石油醚有较好的抗氧化活性，有进一步分离纯化的价值。     

Antioxidant Activity and Cytotoxicity of the Traditional Indonesian Medicine Tahongai (Kleinhovia hospita L.) Extract

We investigated the leaves of Kleinhovia hospita, a plant which has been traditionally used in Indonesia as phytotherapy to cure liver disease, to describe antioxidant materials from plant sources. K. hospita leaves were extracted with methanol and further partitioned into n-hexane, diethyl ether, and ethyl acetate. The antioxidant activity of each fraction and the residue was assessed using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and their cytotoxicity on HepG2 liver cancer cells was determined by a MTT assay. The K. hospita leaf methanol extract showed strong antioxidant activity (96%) compared with vitamin C (98%) by the DPPH method and the measured activity from the subsequent extracts of the methanol extract were 48.9% for n-hexane, 74.0% for diethyl ether, 84.3% for ethyl acetate, and 77.1% for the residue. The MTT assay showed the cytotoxicity of the methanol extract on HepG2 cells at 14%, 76%, and 80% at concentrations of 50μg/mL, 87.5μg/mL, and 125μg/mL, respectively. Leaf extracts of the medicinal plant K. hospita showed potent antioxidant activity and moderate cytotoxicity on HepG2 liver cancer cells.     

Antioxidant and anticancer activities of organic extracts from Platycodon grandiflorum A. De Candolle roots

This study examined the antioxidant and anticancer activities of the petroleum ether extracts from the roots of Platycodon grandiflorum A. DC, which is a plant used as both a herbal medicine and food in Asia. Extracts from Platycodon grandiflorum in petroleum ether were fractionated (fractions I-V) by silica gel column chromatography using gradient solvents (petroleum ether: ethyl ether, 9:1-5:5, v/v). The antioxidant activities of the fractions were evaluated in terms of their inhibition of lipid peroxidation as well as their free radical scavenging activity. Fraction II, which was extracted at an 8:2 mixture of petroleum ether and ethyl ether, exhibited the greatest antioxidant activity among the fractions. On the other hand, the cytotoxicity of each fraction, which was evaluated by the MTT assay using human cancer cell lines (HT-29, HRT-18 and HepG2), was greatest in fraction III, which was extracted with a 7:3 petroleum ether and ethyl ether mixture. Both fractions, II and III, were sub-fractionated by thin layer chromatography, and the sub-fractions each were screened for their antioxidant and anticancer activities. In addition, the antioxidant activity was closely related to the content of phenolic compounds, and the anticancer active fraction exhibited a typical UV absorbance spectrum of polyacetylene.     

The pharmacological screening of Pentanisia prunelloides and the isolation of the antibacterial compound palmitic acid.

The uses of Pentanisia prunelloides in Zulu traditional medicine indicate that the plant is believed to be effective in relieving inflammation, bacterial and viral infections and also stimulating uterine contraction. Aqueous, ethanolic and ethyl acetate extracts of leaves and roots were screened for prostaglandin-synthesis inhibitors and antibacterial and antiviral activity. In the results of the anti-inflammatory assay all the extracts showed cyclooxygenase-1 inhibition. The ethanolic and ethyl acetate extracts showed greater antibacterial activity than the aqueous extracts against Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae). Both root and leaf extracts were found to inhibit viral replication of the Influenza A virus. The ethyl acetate extract was fractionated by silica vacuum liquid chromatography and anti-inflammatory activity was found to be most pronounced in the more polar fractions. The presence of antibacterial activity was confirmed by running the fractions on a thin layer chromatography (TLC) plate and performing a bioautographic assay. The active fraction was further purified by TLC and the major antibacterial compound in the ethyl acetate root extract was identified by GC/MS as palmitic acid.     

Isolation and characterization of antioxidant phenolic compounds from the aerial parts of Hypericum hyssopifolium L. by activity-guided fractionation

Dried methanol extract of Hypericum hyssopifolium subsp. elongatum var. elongatum was dissolved in distilled water, and then fractioned by re-extracting with petroleum ether, chloroform, and ethyl acetate, subsequently. Antioxidant and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities of these fractions were determined, in vitro. The amounts of total phenolic compounds were also determined. None of these fractions showed antioxidant activity, in contrast water and ethyl acetate fractions acted as prooxidant. However, the ethyl acetate fraction exhibited the highest DPPH radical-scavenging activity and the amount of its total phenolic compound was highest, too. Therefore, ethyl acetate fraction was subjected to further separation by chromatographic methods. Thus, five flavonoids (I3,II8-biapigenin, quercetin, quercetin-3-O-alpha-L-arabinofuranoside, quercetin-3-O-beta-D-galactopyranoside, quercetin-3-O-beta-D-galactopyranoside-7-O-beta-D-glucopyranoside) and a napthodianthrone (hypericin) were isolated, and their structures were determined by UV, IR, NMR, and MS spectroscopic methods. All isolated compounds showed antioxidant and DPPH radical-scavenging activities. Although, I3,II8-biapigenin and hypericin were able to show highest antioxidant activity, they had the lowest DPPH radical-scavenging activities. From these results, it can be suggested that these compounds may be used as potential antioxidants. In addition, the petroleum ether fraction was subjected to silica gel column chromatography (CC). Then, n-dotriacontanyl hexadecanoate, bis(2-methylheptyl) phthalate, and beta-sitosterol were isolated from it. It is of interest to present the spectral data of bis(2-methylheptyl) phthalate first time in the present study.     

Enzymatic and non-enzymatic antioxidant,anti-inflammatory and anticancer activities of Floscopa scandens Lour

OBJECTIVE: To explore the total phenolic and flavonoid content, enzymatic, non-enzymatic antioxidant properties, anti-inflammation and anticancer activities of hexane, ethyl acetate and methanol extracts of Floscopa scandens(F. scandens).METHODS: Non-enzymatic antioxidant activity was examined by 2, 2-diphenyl-1-picrylhydrazyl assay, nitric oxide scavenging assay, hydroxyl radical scavenging assay, reducing power assay, hydrogen peroxide scavenging assay, superoxide scavenging assay and metal chelating assay. Enzymatic antioxidant ability was screened for the antioxidant enzymes such as ascorbate oxidase, peroxidase, catalase and polyphenol oxidase. The anti-inflammatory property was proved with the inhibition of protein denaturation and protease inhibitory assays. In vitro anticancer activity was assessed by cell viability assay.RESULTS: Methanol extract contained high amount of phenols(198.41 mg catechol equivalent/gram extract) and flavonoids(101.70 mg quercetin equivalent/gram extract) showed higher activity than hexane and ethyl acetate extracts in all experiments. Fresh plant showed considerable enzymatic antioxidant activity.CONCLUSION: The results revealed that the methanol extracts of F. scandens could be used as a potential source of antioxidant, anti-inflammatory and anticancer bioactive compounds.     

In vivo anti-inflammatory activity of Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. (Euphorbiaceae)

Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. (Euphorbiaceae) is a widely distributed plant in Africa. It is used in the traditional medicine of many African countries for the treatment of bacterial, fungal, parasitic and inflammatory disorders. Aqueous decoction and methanol leaf extracts were tested for their ability to reduce Croton oil-induced oedema in the mouse ear, after topical application. The methanol leaf extract dose-dependently inhibited the Croton oil-induced ear oedema in mice (ID(50)<500 microg/cm(2)). A bio-assay guided liquid-liquid fractionation of this methanol extract gave four active fractions: water insoluble (F1), hexane (F2), ethyl acetate (F3) and water (F4). The hexane fraction showed a very high activity (42% inhibition at 0.7 microg/cm(2)) as compared to the control. The other fractions were less active (F1: 56% at 506.2 microg/cm(2); F3: 57% at 289.3 microg/cm(2); F4: 32% for 203.8 microg/cm(2)) while indomethacin gave 49% of inhibition at 90 microg/cm(2). The activity of F1 and F3 may be at least in part explained by the presence of anti-inflammatory flavonoids (hyperoside and quercitrin, quercitrin being identified in the plant for the first time) while the activity was not correlated to the tannin contents. None of these compounds were detected in the most active F2 fraction. These results support the reported traditional use of this plant against topical inflammatory disorders.     

泽兰抗氧化活性的研究及活性部位的筛选

目的:对中药泽兰进行抗氧化活性的研究,并筛选其主要的活性部位。方法:采用高通量活性筛选技术,以清除DPPH和超氧阴离子自由基能力、还原Fe3+能力及抑制脂质过氧化能力为指标,评价泽兰乙醇总提取物及不同极性部位的抗氧化能力。结果:泽兰及其乙酸乙酯部位(LLE-A.E,MCCM2921)和正丁醇部位(LLE-A.B,MCCM2922)具有较强的清除DPPH(二苯代苦味肼)、超氧阴离子自由基能力、还原Fe3+能力和抑制脂质过氧化能力。结论:泽兰及其不同极性部位具有清除自由基作用,这可以用来解释其在传统应用中的活血化瘀、抗纤维化作用。     

蓝靛果不同提取部位花青素、多酚类的含量测定及体外抗氧化活性

目的:考察4种不同方法测定蓝靛果95%乙醇提取物的石油醚、乙酸乙酯、正丁醇和水层萃取部位的花青素含量并测定其抗氧化活性。方法:以95%乙醇提取蓝靛果,回收溶剂后用水溶解,依次用石油醚、乙酸乙酯和正丁醇萃取,获得蓝靛果4个提取部位。分别用色价法、消光系数法、p H示差法和Na NO2-Al(NO_3)_3-Na OH比色法测定花青素、多酚类的含量,并利用1,1-二苯基-2-三硝基苯肼测定4个提取部位的抗氧化的能力,检测波长517 nm。结果:采用色价法、消光系数法和p H示差法测得正丁醇层中花青素含量最高;而以Na NO2-Al(NO_3)_3-Na OH比色法结果可知,在乙酸乙酯层中多酚类含量最高为29.45%。体外抗氧化活性以乙酸乙酯层最强,正丁醇层和水层抗氧化活性接近,石油醚层抗氧化活性最弱。结论:蓝靛果中不仅花青素有一定的抗氧化活性,多酚类也表现出较强的抗氧化活性。