首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
This study showed for the first time the antioxidant and hypoglycaemic properties of the methanol, n-hexane and ethyl acetate extracts from Senecio stabianus Lacaita, a plant that belongs to the Asteraceae family. The antioxidant activities were carried out using two different in vitro assays, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonate) (ABTS) test. The ethyl acetate extract showed the highest activity with inhibitory concentration 50% (IC(50)) values of 35.5 and 32.7?μg?mL(-1) on DPPH test and ABTS test, respectively. This activity may be related to a good total phenol and flavonoid content. All extracts were also tested for their potential inhibitory activity of α-amylase and α-glucosidase digestive enzymes. The n-hexane extract exhibited the highest α-amylase inhibition with an IC(50) value of 0.21?mg?mL(-1). Through bioassay-guided fractionation processes seven fractions (A-G) were obtained and tested. Based on the phytochemical analysis, the activity of n-hexane extract may be related to the presence of monoterpenes and sesquiterpenes.  相似文献   

2.
Abstract

Ethanol extracts of different parts of Passiflora cincinnata were obtained by maceration. The total phenolic and flavonoid contents were evaluated. The antioxidant activities were determined by β-carotene-linoleic acid bleaching test, 2,2-diphenyl-1-picrylhydrazil (DPPH), and 2,2’-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging. The crude ethanol stem extract showed the highest amount of total polyphenols (45.53?mg gallic acid equivalent/g) while the highest total flavonoid contents (1.42?mg of quercetin equivalent/g) were observed in the leaf extract. The lowest IC50 (25.65?μg/ml) by the DPPH method was observed for the stem extract. The ABTS method showed a significant antioxidant activity for all investigated extracts. The secondary metabolite composition of ethanol extracts was assessed by HPLC-DAD-MS/MS analysis, leading to the identification of fourteen secondary metabolites in P. cincinnata extracts. These results showed the potentiality of this species as a source of phenolic compounds and antioxidants.  相似文献   

3.
This study was designed to evaluate the in vitro antioxidant activities of n-hexane (Hex), dichloromethane (DCM), methanol (MeOH) and essential oils (EO) extracts obtained from Salvia euphratica var. euphratica and Salvia euphratica var. leiocalycina and to determine their essential oil and phenolic acid compositions. The samples were screened for their antioxidant activity by using DPPH and β-carotene/linoleic acid assays. Methanol extracts of both varieties exhibited strong antioxidant activities. Our results showed that rosmarinic acid was dominant phenolic acid of MeOH extracts (39.4 and 55.8?μg?mg?1, respectively). The chemical compositions of essential oils of two varieties were analysed and their main components were determined as eucalyptol (18.4%) and trans-pinocarvyl acetate (24.9%), respectively. It can be said that these varieties could be used as natural antioxidant.  相似文献   

4.
Although avocado is a superfood rich in phytochemicals with high antioxidant activities, studies on the antibacterial properties of its pulp are limited, except for seed and peel portions. In this study, three types of solvent (acetone, methanol, and diethyl ether) were used to obtain the extracts from “Maluma” avocado pulp powder prepared by infrared drying. The extracts were analyzed for total polyphenols, phytopigments (total chlorophylls and carotenoids), antioxidant activities (ferric-reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays), and antibacterial activities against seven pathogens (Shigella sonnei ATCC 9290, Escherichia coli ATCC 8739, Salmonella typhi ATCC 6539, Vibrio parahaemolyticus ATCC 17802, Proteus mirabilis ATCC 25933, Staphylococcus aureus ATCC 6538, and Bacillus cereus ATCC 11778). The results showed that the acetone solvent could extract the highest polyphenols and chlorophylls with the highest antioxidant activity in terms of ABTS and DPPH assays. In contrast, diethyl ether exhibited the most significant content of carotenoids and FRAP values. However, the methanol extract was the best solvent, exerting the strongest antibacterial and meaningful antioxidant activities. For the bacterial activities, Gram-positive pathogens (Bacillus cereus and Staphylococcus aureus) were inhibited more efficiently by avocado extracts than Gram-negative bacteria. Therefore, the extracts from avocado powder showed great potential for applications in food processing and preservation, pharmaceuticals, and cosmetics.  相似文献   

5.
Li X  Chen D  Mai Y  Wen B  Wang X 《Natural product research》2012,26(11):1050-1053
Five Radix Astragali (RA) extracts were prepared and their antioxidant activities were measured in vitro using ABTS [2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid diammonium salt)], DPPH?·?(1,1-diphenyl-2-picrylhydrazyl radical), reducing power, ?O?? and ?OH assays. Their chemical contents were then determined, including total phenolics, total flavonoids, total saponins and total sugars. The 1/IC?? values of the various antioxidant assays were used to evaluate the level of antioxidant activity of the RA extracts (plot showing 1/IC?? values vs. chemical contents), and the average R values (correlation coefficients) of total phenolics and total flavonoids were 0.762 and 0.638. In contrast, the average R values of the total saponins and total sugars were -0.0386 and -0.132, respectively. This large difference clearly demonstrates that the antioxidant effects of RA in vitro might be generally considered to be a result of the presence of phenolic compounds (including flavonoids) but not astragalosides and polysaccharides.  相似文献   

6.
The antioxidant properties of extracts of Sybaris liquorice roots have been assessed using 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay. The extracts, obtained by Soxhlet extraction (Et(2)O, AcOEt, MeOH and BuOH) of the yellow (inner part) and brown (cortex) root powders ensuing from decortication of the raw dry roots, followed by separation and powderisation, were analysed for their scavenging activity by evaluating the colourimetric decrease in the absorbance of DPPH. The highest antioxidant activity (98.39?±?0.56%) was observed in the case of the Et(2)O extract of the brown powder, at a concentration of 3.33?mg?mL(-1). Moreover, the total phenolic content of the extracts was determined using the Folin-Ciocalteu reagent and expressed as milligram gallic acid equivalent per gram of dry extract. Our results show that the Et(2)O extract of the liquorice root cortex could be used as an attractive natural source of antioxidant additives for food, cosmetic or pharmaceutical applications.  相似文献   

7.
Thai jasmine rice (Oryza sativa L. cv. KDML105) is highly valued due to its subtle aroma, robust seed characteristics and high nutritional quality. Low-energy ion-beam bombardment was chosen to improve the quality of jasmine rice by mutation induction. One mutated variety, named BKOS, was found to exhibit a deep purple colour due to an increased accumulation of anthocyanin. The total phenolic content and antioxidant activities of cooked and uncooked rice extracts were compared with KDML105, BKOS and other rice mutants created by a low-energy ion beam. The BKOS extracts showed the highest total phenol content (0.140 and 0.096?mg of gallic acid equivalent (GAE)?g(-1) dry extract from uncooked and cooked rice, respectively). The BKOS extracts also had improved antioxidant activities, determined using three standard methods: 2,2'-diphenyl-1-picrylhdrazyl (DPPH) free radical scavenging, ABTS radical cation (ABTS?(+)) decolourisation and ferric-reducing antioxidant power assays. BKOS extracts showed 2-2.5-fold increased levels for each method. Interestingly, there was no significant difference between the antioxidant activities of the cooked and uncooked BKOS rice extracts. The increased quantity of antioxidants in this anthocyanin-based natural product could allow antioxidants to be consumed by a wider population than what is currently possible.  相似文献   

8.
Culinary herbs and spices are known to be good sources of natural antioxidants. Although the antioxidant effects of individual culinary herbs and spices are widely reported, little is known about their effects when used in combination. The current study was therefore undertaken to compare the antioxidant effects of crude extracts and essential oils of some common culinary herbs and spices in various combinations. The antioxidant interactions of 1:1 combinations of the most active individual extracts and essential oils were investigated as well as the optimization of various ratios using the design of experiments (DoE) approach. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays were used to determine the antioxidant activity, and MODDE 9.1® software (Umetrics AB, Umea, Sweden) was used to determine the DoE. The results revealed synergism for the following combinations: Mentha piperita with Thymus vulgaris methanol extract (ΣFIC = 0.32 and ΣFIC = 0.15 using the DPPH and FRAP assays, respectively); Rosmarinus officinalis with Syzygium aromaticum methanol extract (ΣFIC = 0.47 using the FRAP assay); T. vulgaris with Zingiber officinalis methanol extracts (ΣFIC = 0.19 using the ABTS assay); and R. officinalis with Z. officinalis dichloromethane extract (ΣFIC = 0.22 using the ABTS assay). The DoE produced a statistically significant (R2 = 0.905 and Q2 = 0.710) model that was able to predict extract combinations with high antioxidant activities, as validated experimentally. The antioxidant activities of the crude extracts from a selection of culinary herbs and spices were improved when in combination, hence creating an innovative opportunity for the future development of supplements for optimum health.  相似文献   

9.
Prunella vulgaris L. (PV, Labiatae) is known as a self-heal herb. The different extracts of dried spikes were studied for the best antioxidant active compounds. The 60% ethanol extract (P-60) showed strong antioxidant activity based on the results of 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonic acid (ABTS˙+), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assay methods. High performance liquid chromatography (HPLC) and LC/MS analysis showed that the main active compounds in P-60 were phenols, such as caffeic acid, rosmarinic acid, rutin and quercetin. Total phenols were highly correlated with the antioxidant activity (R2=0.9988 in ABTS˙+; 0.6284 in DPPH and 0.9673 FRAP tests). P-60 could inhibit significantly the tumor growth in C57BL/6 mice. It can also been showed that increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) content in serum of tumor-bearing mice. These results suggested that P-60 extract had high antioxidant activity in vitro and in vivo and total phenols played an important role in antioxidant activity for inhibition of tumor growth.  相似文献   

10.
Plant extracts are one of the best possible sources of bioactive molecules, and are being used globally as an antioxidants and natural antimicrobial compounds. In current study, Schefflera vinosa leaves extract was prepared through Soxhlet extraction procedure using methanol and chloroform as solvents. The extract was investigated for total antioxidant, phenolic and flavonoid contents, free radical scavenging and antimicrobial activities. The free radical scavenging activities were evaluated through 2,2- diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzotiazolin-6-sulfonic acid (ABTS) and Ferric-reducing/ antioxidant power (FRAP) assay. The antimicrobial activity of extract was determined through poisoned food method. The methanolic extract has exhibited high antioxidant, phenolic, and flavonoid activities compared to chloroform extract. Similarly, free radical scavenging activities (ABTS, DPPH and FRAP) were higher in methanolic extract. Further, Fourier-Transform Infrared Spectroscopy (FTIR) used to determine the functional group and Gas chromatography-mass spectrometry (GC–MS) to elucidate volatile composition of the crude extract. Different functional group like N-H, O-H, C-O, C-N, C-H, C=O, C≡C and C-O-H presence indicate the existence of many metabolites in the extracts. GC–MS study identified 61 compounds and subsequently, these molecules were screened virtually using DockThor. Furthermore, antimicrobial study was confirmed against rice pathogens like Magnaporthe oryzae (M. oryzae) and Xanthomonas oryzae pv. oryzae (Xoo). Molecular docking study further suggested that phytomolecules (3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris (trimethylsiloxy) tetrasiloxane, and 2-Methoxy-5-methylthiophene) targets Histone Deacetylase (HDAC) of M. oryzae and Peptide Deformylase (PDF) of Xoo, which could inhibit their growth. Hence, this study indicated that Schefflera vinosa extracts could be an important ingredient as an antioxidant as well as antimicrobial agent against rice pathogens.  相似文献   

11.
The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect and total phenolic contents were evaluated for the screening of singlet oxygen ((1)O(2)) quenching efficacy of various seed extracts from Rumex crispus L. The butanol and ethyl-acetate extracts displayed remarkable effect of DPPH as compared to positive control ascorbic acid. The concentrations (QC(50)) of butanol and ethyl-acetate extracts required to exert 50% reducing effect on (1)O(2) were found to be 116 and 82 μg mL(-1), respectively. Both extracts were also found to protect the in vitro biological system from the detrimental effect of (1)O(2) on type II photosensitization in Escherichia coli, red blood cell, lactate dehydrogenase and histidine. Among all the tested extracts, the ethyl-acetate and butanol extracts contained higher amount of total phenolic contents. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce photo-produced oxidative stress involving reactive oxygen species in living organisms.  相似文献   

12.
In this work, an evaluation of the biological activities of Globularia alypum L. extracts and their global chemical composition was realized. Extracts from G. alypum were obtained by two extraction methods. The composition of polyphenols (8.5-139.95 g gallic acid equivalent/Kg of dry mass), tannins (1.39-18.65 g catechin equivalent/Kg of dry mass), anthocyanins (8.17-70.69 mg cyanidin equivalent/Kg of dry mass) and flavonoids (0.31-19.28 g quercetin equivalent/Kg of dry mass) was evaluated. The samples were subjected to a screening for their antioxidant activities using the DPPH* and ABTS*+ assays. For the first time, the anti-tuberculosis activity (H(37)Rv) for G. alypum was tested against Mycobacterium tuberculosis. The strongest antioxidant activity was obtained for the methanol extract (IC(50 ) = 15.58 ± 0.168 mg/L) and the best anti-tuberculosis activity was obtained for the petroleum ether extract (IC(50 )= 77 mg/L). We have found a positive correlation between the total phenolics content and the antioxidant activity R2 = 0.88 (DPPH*) and R2 = 0.97 (ABTS*+). We have found also a positive correlation between the flavonoid content and the antioxidant activity R2 = 0.91 (DPPH*) and R2 = 0.91 (ABTS*+).  相似文献   

13.
The occurrence of three known benzophenones, namely annulatophenonoside, acetylannulatophenonoside and annulatophenone as well as a flavonol O-glycoside guajaverin in the aerial parts of Hypericum maculatum Crantz was established. In addition, hyperoside, isoquercitrin and miquelianin were isolated from this plant, as well. Radical scavenging and antioxidant activities of the isolated compounds were examined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) free radicals, ferric reducing antioxidant power (FRAP) assay and inhibition of lipid peroxidation in linoleic acid system by the ferric thiocyanate method. Isoquercitrin demonstrates the highest DPPH radical scavenging (96.6?±?0.3%), FRAP (23.8?±?0.2 Trolox equivalent, TE?mol?1) and antioxidant activity in linoleic acid system. Guajaverin and acetylannulatophenonoside show significantly strong ABTS radical scavenging activity (93.9?±?0.4% and 93.4?±?0.6%, respectively), which is comparable to that of ascorbic acid (96.2?±?0.4%).  相似文献   

14.
The antioxidant properties of the water and ethanol leaf extracts of kinkeliba (Combretum micranthum) were investigated, including scavenging of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (IC?? values: 8.02?±?0.34 for the ethanol extract [KE] and 9.1?±?0.28 for the water extract [KW]), the 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical (IC(50) values: 7.4?±?0.14 for KE and 11.8?±?0.01 for KW) and the hydroxyl radical (58.1% for KE and 61.1% for KW). The ferric thiocyanate method, reducing power, metal chelating activity, an assay of protein oxidation and the β-carotene-linoleic bleaching assay were also used. Butylated hydroxytoluene and ascorbic acid were used as the reference antioxidant compounds. At 20 mg mL?1 concentration, KW and KE provided 36.8% and 75.1% inhibition of lipid peroxidation of linoleic acid emulsion, respectively. The IC?? values of the ethanol extract in ABTS and DPPH tests were significantly lower than those from the water extract. Furthermore, crude polyphenols were extracted from kinkeliba leaf with 90% ethanol solution using a water bath treatment and then purified by a macroporous resin, AB-8. The polyphenols from kinkeliba leaf were subjected to analyses by RP-HPLC and ESI-MS. The dominant polyphenols in kinkeliba leaf were identified as gallic acid, rutin trihydrate, (+)-catechin and benzoic acid.  相似文献   

15.
Phenolic compounds are widely distributed in Nature and act as pharmacologically active constituents in many herbal medicines. They have multiple biological properties, most notably antioxidant, antibacterial and cytotoxic activities. In the present study an attempt to correlate the phenolic composition of leaf, flower and wood extracts of Piper imperiale, with antioxidant, antitubercular and cytotoxic activities was undertaken. The total phenol content ranged from 1.98 to 6.94 mg GAE/gDW among ethanolic extracts, and gallic acid, catechin, epicatechin, ferulic acid, resveratrol and quercetin were identified and quantified by HPLC. DPPH and ABTS assays showed high antioxidant activity of the leaf extract (EC(50ABTS) = 15.6 μg/mL, EC(50DPPH) = 27.3 μg/mL) with EC?? in the same order of magnitude as the hydroxyquinone (EC(50ABTS) = 10.2 μg/mL, EC(50DPPH) = 15.7 μg/mL). The flower extract showed strong antimicrobial activity against Mycobacterium tuberculosis H??Rv. All the extracts exhibited dose-dependent cytotoxic effects against MCF-7 cancer cells. This is the first time that a Piper extract has been found to be highly active against M. tuberculosis. This study shows the biological potential of Piper imperiale extracts and gives way to bio-guided studies with well-defined biological activities.  相似文献   

16.
The methanol, ethyl acetate and chloroform extracts of selected Croatian plants were tested for their acetylcholinesterase (AChE) inhibition and antioxidant activity. Assessment of AChE inhibition was carried out using microplate reader at 1?mg?mL?1. Antioxidant capacities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test and ferric reducing/antioxidant power assay (FRAP). Total phenol content (TPC) of extracts were determined using Folin-Ciocalteu colorimetric method. Out of 48 extracts, only methanolic extract of the Salix alba L. cortex exerted modest activity towards AChE, reaching 50.80% inhibition at concentration of 1?mg?mL?1. All the other samples tested had activity below 20%. The same extract performed the best antioxidative activity using DPPH and FRAP method, too. In essence, among all extracts used in the screening, methanolic extracts showed the best antioxidative activity as well as highest TPC.  相似文献   

17.
The antioxidant properties of five different extracts (Et?O, CHCl?, EtOAc, n-BuOH, and H?O) of Ocimum basilicum L. and Origanum vulgare L. were studied. Antioxidant activity was assessed in six different model systems. Free radical scavenging capacity (RSC) was evaluated by measuring the scavenging capacity of extracts on DPPH, NO, O??? and OH radical, as well as on hydrogen peroxide (H?O?). In addition, the protective effects on lipid peroxidation in liposomes (LPx) were evaluated by TBA-assay using the Fe2?/ascorbate induction system. The amount of total phenolic compounds and content of total flavonoids was also determined. EtOAc, n-BuOH and H?O extracts of O. basilicum and O. vulgare expressed very strong scavenger activity. Furthermore, the mentioned extracts showed notable inhibition of LPx. On the other hand, Et?O and CHCl? extracts showed much weaker effect in the neutralization of DPPH, NO and O??? radicals and the neutralization of H?O?. When examining the production of OH radicals and inhibition of LPx, the Et?O and CHCl? extracts showed weak prooxidative properties. The observed differences in antioxidant activity could be partially explained by the levels of phenolics and flavonoids in the investigated O. basilicum and O. vulgare extracts.  相似文献   

18.
Profound research has been done on the medicinal value of Brassica nigra (BN) seeds, and the leaves of the plant have been investigated in this study. The methanol extracts of the leaves were subjected to several in?vitro studies. The antioxidant activity of methanol extract was demonstrated with a wide range of concentration, 10-500?μg?mL(-1), and the antioxidant activity increased with the increase in concentration. Total phenol content was found to be 171.73?±?5.043 gallic acid equivalents and the total flavonoid content 7.45?±?0.0945 quercetin equivalents. Further quantification and identification of the compounds were done by HPTLC and GC-MS analyses. The predominant phenolic compounds determined by HPTLC were gallic acid, followed by quercetin, ferulic acid, caffeic acid and rutin. The free radical quenching property of BN leaf extract suggests the presence of bioactive natural compounds.  相似文献   

19.
Xia DZ  Yu XF  Zhu ZY  Zou ZD 《Natural product research》2011,25(20):1893-1901
The total phenolic and flavonoid, antioxidant and antibacterial activities of six Sonchus wild vegetables (Sonchus oleraceus L., Sonchus arvensis L., Sonchus asper (L.) Hill., Sonchus uliginosus M.B., Sonchus brachyotus DC. and Sonchus lingianus Shih) in China were investigated. The results revealed that S. arvensis extract and S. oleraceus extract contained the highest amount of phenolic and flavonoid, respectively. Among the methanol extracts of six Sonchus species, S. arvensis extract exhibited the highest radical (DPPH and ABTS+ scavenging power and lipid peroxidation inhibitory power. It also exhibited the highest reducing power at 500?μg?mL?1 by A (700)?=?0.80. The results of antibacterial test indicated that the S. oleraceus extract showed higher activity than the other five Sonchus wild vegetables extracts, both in Gram-negative bacteria (Escherichia coli, Salmonella enterica and Vibrio parahaemolyticus) and in a Gram-positive bacterium (Staphylococcus aureus). These results indicate that Sonchus wild food plants might be applicable in natural medicine and healthy food.  相似文献   

20.
In this study the antioxidant and cytotoxicity activity of the Adonidia merrillii fruits were investigated using different solvent polarities (methanol, ethyl acetate and water). The results showed that the total phenolic and flavonoid contents of the methanolic extract was higher compare with other extract with respective values of 17.80 ± 0.45 mg gallic acid equivalents/g dry weight (DW) and 5.43 ± 0.33 mg rutin equivalents/g DW. Beside that The RP-HPLC analyses indicated the presence of gallic acid, pyrogallol, caffeic acid, vanillic acid, syringic acid, naringin and rutin. In the DPPH, NO2 and ABTS scavenging assays, the methanolic extract exhibited higher antioxidant activity as compared to the ethyl acetate and water extracts. The extracts exhibited moderate to weak cytotoxic activity in the assays using human hepatocytes (Chang liver cells) and NIH/3T3 (fibroblasts cell) cell lines. The findings showed the Adonidia merrillii fruit extracts to possess considerable antioxidant and cytotoxicity properties. The fruit, therefore, is a potential candidate for further work to discover antioxidant and cytotoxic drugs from natural sources.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号