共查询到20条相似文献，搜索用时 46 毫秒
1.
Motlhanka DM 《Pakistan journal of biological sciences: PJBS》2008,11(5):805-808
Water and methanol extracts from roots of Ozoroa paniculosa (Anarcardiaceae); seeds of Colophospermum mopane (Caesalpiniaceae) and Cucumis metuliferus (Cucurbitaceae) ripe fruits were assessed for in vitro antioxidant activity. Free radical scavenging activity was measured spectrophotometrically as maximum fading power of DPPH at 525 nm. Water and methanol extracts of Ozoroa paniculosa exhibited higher scavenging potency than extracts of either Colophospermum mopane or Cucumis metuliferus at all tested concentrations. None of the extracts from Cucumis metuliferus exhibited any recognizable free radical scavenging activity. Above 50 microg mL(-1) both water and methanol extracts of Ozoroa paniculosa exhibited 91% scavenging activity similar to the control compounds L-ascorbic acid (91%) and (-) epicatechin (92%). Between 50-100 microg mL(-1), water and methanol extracts of Colophospermum mopane exhibited scavenging potency of < or = 70%. However, above 100 microg mL(-1), both water and methanolic extracts of C. mopane exhibited scavenging activity > 70%. Chloroform extracts of all the tested plants showed poor scavenging activity (< 30%). The order of scavenging potency for the tested samples was as follows: L-ascorbic acid > or = epicatechin > O. paniculosa (methanolic extract) > O. paniculosa (water extract) > O. paniculosa (ethylacetate extract) > C. mopane (methanolic extract) > C. mopane (water extract) > all extracts of C. metuliferus. These findings lend credence to the use of these plants as anti-inflammatory and antioxidant agents in folk medicine. 相似文献
2.
Wimonrat TongpoothornSaksit Chanthai Manop SriutthaKanda Saosang Chalerm Ruangviriyachai 《Industrial Crops and Products》2012,36(1):437-444
The present work is designed to evaluate the bioactive properties of the crude methanolic extract of Jatropha curcas oil and its solvent fractions. The crude methanolic extract obtained was fractionated using a hydrophilic lipophilic balanced (HLB) cartridge and then eluted with different solvents in the order of hexane (F1), dichloromethane (F2), chloroform (F3), ethyl acetate (F4) and methanol (F5), respectively. Total phenolic content of the crude methanolic extract and its fractions was in the range of 0.19-4.5 mg/g as gallic acid equivalent. Antioxidant activity of the crude methanolic extract and its fractions were determined by two complementary test methods, namely, phenanthroline method and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. All samples demonstrated weak antioxidant activity (150-851 μmol Fe/100 g of the extract and IC50 of 1.05-13.5 mg/mL). When compared to butylated hydroxytoluene (BHT), a reference synthetic antioxidant, both showed weaker antioxidative potential. The evaluation of antimicrobial activity of the extracts was performed using a disc diffusion method and a micro-well dilution method against six economic plant disease bacteria. The results showed that all extracts possessed strong to moderate antibacterial activity with varying degrees of growth inhibition against the test bacteria. The minimum inhibitory concentrations (MIC) were in the range of 14.92-428.6 μg/mL. In addition, the chemical constituents in each fraction of the extract were subjected to analyze by gas chromatography-mass spectrometry (GC-MS). The eleven constituents were identified. Among them, 2,4-di-tert-butylphenol, methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and linoleic acid may be the main cause of its strong antibacterial activity. Therefore, this oil present in the methanolic extract had great potential as effective antibacterial sources. 相似文献
3.
Vadivel V Nandety A Biesalski HK 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):245-253
The methanolic extract of Cassia hirsuta L. seed materials, an underutilized food legume collected from India, was analyzed for antioxidant activity and health relevant functionality. The methanolic extract of raw seeds contained a total free phenolic content of 15.82?±?1.69 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1,446 mmol Fe[II]/mg extract), inhibition of ß-carotene degradation (48.81%) and scavenging activity against DPPH (64.40%) and superoxide (43.78%) radicals were exhibited by the raw samples. Further, 83.11% of α-amylase and 62.79% of α-glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay were also recorded. Sprouting + oil-frying caused an apparent increase on the total free phenolic content and a significant improvement in the antioxidant and free radical scavenging capacity of methanolic extract of C. hirsuta seeds, while soaking + cooking as well as open-pan roasting treatments showed diminishing effects. The analysis of the phenolic profile revealed the presence of gallic acid, p-coumaric acid and (+)-catechin in the methanolic extract of these seeds. 相似文献
4.
以芦丁与Vc为对照,测定云南普洱茶不同溶剂提取物清除DPPH自由基、羟自由基、超氧阴离子自由基、亚硝酸盐的能力及其还原力.结果表明:普洱茶不同溶剂提取物的抗氧化活性与其浓度成正相关,对DPPH自由基、羟自由基与超氧阴离子有较强的清除作用,对亚硝酸盐的清除作用不明显,具有一定的还原力.其中,乙醇沉析物、正丁醇提取物、乙醇提取物、乙醇溶解物对DPPH.自由基清除效果较好,相同浓度下优于芦丁;水提取物、乙醇沉析物及乙酸乙酯提取物对羟自由基清除效果较好,但效果不如Vc;乙酸乙酯提取物对超氧阴离子自由基和亚硝酸盐的清除作用较好,还原力也很强. 相似文献
5.
İsmail Hamad Özlem Erol-Dayi Murat Pekmez Evren Önay-Uçar Nazlı Arda 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):44-49
The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular
oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed
a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC50 value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and
methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active
than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner.
Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate
that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used
as a natural additive in food, cosmetic and pharmaceutical industries. 相似文献
6.
Antioxidant and Antifungal Activity of <Emphasis Type="Italic">Verbena officinalis</Emphasis> L. Leaves 总被引：1，自引：1，他引：0
Casanova E García-Mina JM Calvo MI 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(3):93-97
The scavenging activity against DPPH (1,1-diphenil-2-picrylhydrazyl) radical and the antifungal effect against chloroform, ethyl acetate and 50% methanolic extracts of Verbena officinalis leaves were investigated. The activity of different fractions of 50% methanolic extract and some isolated compounds were also investigated. The results suggest that 50% methanolic extract and caffeoyl derivatives could potentially be considered as excellent and readily available sources of natural antifungal and antioxidant compounds. 相似文献
7.
椰子种皮油提取物的抗氧化活性研究 总被引：1，自引：0，他引：1
测定椰子种皮油提取物中的总酚含量,对羟基自由基、DPPH（1,1-二苯基-2-三硝基苯肼）自由基、ABTS（2,2连氮-双-（3-乙基苯并噻咪唑-6-磺酸）自由基清除能力和总抗氧化能力等抗氧化活性指标。结果表明,椰子种皮油提取物中含有较高的总酚含量（68 mg/g）,提取物浓度为0.1 mg/mL时对羟基自由基的清除率为56.89％,对DPPH自由基的清除率为71.0％,对ABTS自由基的清除率为96.4％,表明椰子种皮油提取物具有很好的抗氧化活性。 相似文献
8.
为确定野葛愈伤组织提取物的清除自由基和抗氧化活性及开发新型天然抗氧化剂提供试验依据,采用1,1-二苯基苦基苯肼(DPPH.)的有机自由基体系以及羟自由基和超氧阴离子自由基两种无机活性氧自由基体系,检测野葛愈伤组织提取物的体外清除自由基和抗氧化活性,并与野葛根提取物、葛根素、Vc和茶多酚进行对比研究。结果表明:野葛愈伤组织提取物对DPPH.自由基的清除能力较强,与野葛根提取物、茶多酚的清除能力相当,且显著优于葛根素和Vc;野葛根提取物的羟自由基(.OH)清除活性最高,茶多酚和野葛愈伤异黄酮次之,Vc对.OH的清除活性稍弱;野葛愈伤组织提取物的羟自由基清除活性随处理浓度增加而提高;野葛愈伤组织提取物、野葛根提取物和Vc均具有较强的清除O-2.能力,均显著高于葛根素和茶多酚。说明野葛愈伤组织提取物具有较强的清除自由基和抗氧化活性。 相似文献
9.
10.
目的研究鹿产品的保湿、抗氧化和抑制酪氨酸酶活性的作用。方法以梅花鹿鹿茸、鹿胎、鹿角盘为原料,分别以75%乙醇和蒸馏水为溶剂提取,冷冻干燥得到鹿产品的提取物,考察了鹿产品各提取物的保湿作用,以酶标仪测定各样品的DPPH清除率和酪氨酸酶的抑制率。结果鹿产品在不同程度上均有一定的保湿作用,其在湿度较高的条件下保湿效果更好,具有长效的保湿作用;鹿产品对DPPH自由基的清除效果从强到弱依次顺序为鹿胎水提物鹿角盘水提物鹿茸水提物鹿茸醇提物鹿胎醇提物鹿角盘醇提物;鹿产品对酪氨酸酶有一定的抑制作用,鹿茸水提物对酪氨酸酶的抑制作用最强,IC50为31.932mg/ml,鹿茸醇提物对酪氨酸酶的抑制率较低,IC50为51.530mg/ml。结论鹿产品具有保湿、抗氧化和抑制酪氨酸酶活性的作用,具备护肤作用的相关基础活性。 相似文献
11.
Karim Hosni Marwa JemliSalma Dziri Yacine M’rabetAsma Ennigrou Ahlem SghaierHervé Casabianca Emmanuelle VullietNadia Ben Brahim Houcine Sebei 《Industrial Crops and Products》2011,34(3):1622-1628
The effect of stage of maturity on total lipids, fatty acids, yields and essential oil composition and their antimicrobial and free radical scavenging activities of the Schinus molle fruits was investigated. The content of total lipids varied from 2.87 to 5.35% (w/w, dw) and were rich in unsaturated fatty acids particularly linoleic acid. As maturation progress, the essential oil yield dropped from 5.18% to 1.15%. Monoterpene hydrocarbons with α-phellandrene (35.15-40.38%), limonene + β-phellandrene (21.47-36.62%), β-myrcene (7.61-24.96%) and α-pinene (1.92-2.58%) were found to be the main components. At the same time, the essential oils were evaluated for their antimicrobial and free radical scavenging activities. They were found to be active against Bacillus subtilis, Bacillus cereus, Salmonella typhymurium and Escherichia coli but they do not inhibit the growth of Candida albicans. Conversely, they showed very weak activity against the DPPH radical. In both assay, the oil derived from the intermediate stage was reported as more efficient. 相似文献
12.
I. Erdogan Orhan E. GunerN. Ozturk F.S. SenolS. Aslan Erdem M. KartalB. Sener 《Industrial Crops and Products》2012,37(1):213-218
In the present study, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase inhibitory and antioxidant activities of the fruit and leaf extracts of Melia azedarach L. (Meliaceae) of Turkish origin were evaluated. Enzyme inhibitory activity of the extracts was tested in vitro using ELISA microplate reader. Antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelation, and ferric-reducing antioxidant power (FRAP) assays. Phenolic composition of the extracts was elucidated by high performance liquid chromatography (HPLC) and fatty acid compositions of the fatty oils of the fruits and leaves were elucidated by gas chromatography-mass spectrometry (GC-MS). The ethyl acetate extract from the leaves showed the highest inhibition against AChE (33.63 ± 1.40%) and BChE (92.89 ± 3.05%). The methanol extract from the leaves exerted the best antioxidant activity in DPPH radical scavenging and FRAP assays, while the ethyl acetate extracts of the fruits and leaves had the most notable effect in metal-chelation assay. 相似文献
13.
14.
利用气相色谱-质谱联用技术（GC-MS）,对苦丁茶超声辅助不同有机溶剂（乙醇、乙酸乙酯、石油醚）提取物及超临界CO2萃取物的体外抗氧化活性（DPPH自由基清除能力、羟基自由基清除活性、超氧阴离子自由基清除活性和ABTS +自由基清除能力）进行比较分析。结果表明,苦丁茶不同提取物DPPH清除能力和超氧阴离子自由基清除活性依次为：超声-乙醇提取物>超临界CO2萃取物>超声-乙酸乙酯提取物>超声-石油醚提取物,羟基自由基和ABTS +自由基清除能力依次为：超声-乙醇提取物>超声-乙酸乙酯提取物>超临界CO2萃取物>超声-石油醚提取物。GC-MS结果显示,苦丁茶不同提取物中主要有5类物质,共有49种化学成分,7种共有成分。 相似文献
15.
The stem bark extract of S. ellipticum (Hochst) Pax was investigated for its antioxidant properties in this study. The extract was evaluated for antioxidant activity in vitro in terms of its ability to inhibit lipid peroxidation and its free radical scavenging, reducing and metal chelation powers. The total amount of phenolic compounds in the extract was also determined in terms of gallic acid equivalent. The extract produced effective free radical scavenging and reducing activities in a dose dependent fashion. The extract exhibited noticeable inhibition of lipid peroxidation of linoleic acid emulsion. These activities were less than that of ascorbic acid and 2,6-Di-tert-butyl-4-methylphenol used as positive controls. The extract however demonstrated poor iron chelating ability compared to ethylene diamine tetraacetic acid. The total phenolic content of the extract was 50.61 +/- 0.08 mg g(-1) in terms of gallic acid. This study showed that the stem bark extract of S. ellipticum exhibits significant antioxidant activity and is a good source of natural antioxidants. 相似文献
16.
采用水蒸气蒸馏法分别从山苍子雌花和雄花中提取精油，并通过GC-MS气质联用仪对其成分分析，从山苍子雌花精油中鉴定出47种化合物，占总峰面积的98.44％，山苍子雄花精油中鉴定出43种化合物，占总峰面积的98.04％。采用体外抗氧化活性测定法，表明山苍子雌花和雄花精油具有一定的抗氧化活性。还原力测定IC50值，雄花为2.330 mg/mL，雌花为1.473 mg/mL；清除DPPH自由基IC50值，雄花为41.62 mg/mL，雌花为9.663 mg/mL；清除羟自由基IC50值，雄花为56.95 mg/mL，雌花为77.98 mg/mL。 相似文献
17.
S. Sreelatha P. R. Padma 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(4):303-311
Antioxidants play an important role in inhibiting and scavenging free radicals, thus providing protection to human against
infections and degenerative diseases. Current research is now directed towards natural antioxidants originated from plants
due to safe therapeutics. Moringa oleifera is used in Indian traditional medicine for a wide range of various ailments. To understand the mechanism of pharmacological
actions, antioxidant properties of the Moringa oleifera leaf extracts were tested in two stages of maturity using standard in vitro models. The successive aqueous extract of Moringa oleifera exhibited strong scavenging effect on 2, 2-diphenyl-2-picryl hydrazyl (DPPH) free radical, superoxide, nitric oxide radical
and inhibition of lipid per oxidation. The free radical scavenging effect of Moringa oleifera leaf extract was comparable with that of the reference antioxidants. The data obtained in the present study suggests that
the extracts of Moringa oleifera both mature and tender leaves have potent antioxidant activity against free radicals, prevent oxidative damage to major biomolecules
and afford significant protection against oxidative damage. 相似文献
18.
为了优化磷酸化改性花生分离蛋白-多肽膜制备工艺条件，在单因素基础上，通过响应面Box-Benhnken进行实验设计。结果表明，最优工艺参数：蛋白浓度8%、pH值8.2、甘油百分含量（占蛋白）13.4%、黄原胶百分含量（占蛋白）1%、时间60min、温度69℃、超声波功率270W、超声波频率28kHz、多肽溶液的浓度61mg/mL；此工艺条件下，膜厚度、吸水率和透光率理论预测值分别为86μm、41.9%和53.6%，验证实验值分别为88±2μm、43.1±1.2%和52.4±1.5%，两者的差值分别为2.33%、2.86%和2.24%，说明响应面二次模型的拟合良好；磷酸化改性花生分离蛋白-多肽膜的抗拉强度9.62MPa、断裂延伸率101.68%、溶解性47.69%、水蒸气透过率6.95 g•m-2· h-1等功能性质和DPPH自由基清除活性IC50值7.70 mg·mL-1、羟自由基清除活性IC50值5.98 mg·mL-1、超氧阴离子自由基清除活性IC50值4.20 mg·mL-1、铁离子螯合力活性IC50值3.79 mg·mL-1、铜离子螯合力活性IC50值13.61 mg·mL-1、脂质过氧化抑制活性IC50值8.62 mg·mL-1、铁还原力IC50值13.93mg·mL-1、钼还原力IC50值5.49mg·mL-1等抗氧化活性较磷酸化改性花生分离蛋白膜有所改善。本研究结果为磷酸化改性花生分离蛋白在蛋白膜方面的应用提供一种新途径。 相似文献
19.
采用分光光度法,考察露兜果实浸膏的多酚含量及其对1,1-二苯基-2-三硝基苯肼(DPPH)自由基、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵(ABTS)自由基和羟自由基的清除活性,并采用生物自显影技术,考察露兜果实浸膏对马铃薯炭疽病菌、草莓炭疽病菌及黄柏炭疽病菌的抑制作用。结果表明：露兜果实浸膏中多酚含量为152.6 μg/mg,对DPPH自由基、ABTS自由基和羟自由基均具有一定的清除活性,且呈现量效关系;此外,还发现其对马铃薯炭疽病菌和草莓炭疽病菌的生长均有一定的抑制作用。 相似文献
20.
大豆豆渣粗提物清除DPPH自由基活性及其协同效应的研究 总被引：3，自引：0，他引：3
用二苯代苦味肼基自由基(DPPH)-TLC法和酶标仪法对大豆豆渣石油醚、乙酸乙酯、丙酮、乙醇粗提物的自由基清除活性进行了定性和定量分析,考察了抗氧化剂维生素C、柠檬酸对大豆豆渣乙醇粗提物清除DPPH自由基活性的协同效应。结果表明:大豆豆渣不同极性粗提物均有一定的自由基清除活性,其中乙醇粗提物的自由基清除活性最强,在浓度为10.0 mg.mL-1,于37℃下保温15 min时,对0.4 mg.mL-1的DPPH自由基的清除率可达76.48%;维生素C和柠檬酸对大豆豆渣乙醇粗提物均能产生一定的协同效应,且维生素C的协同作用强于柠檬酸。 相似文献