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1.
Silymarin, a known standardized extract obtained from seeds of Silybum marianum is widely used in treatment of several diseases of varying origin. In the present paper, we clarified the antioxidant activity of silymarin by employing various in vitro antioxidant assay such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by Fe3+ ? Fe2+ transformation method and Cuprac assay, superoxide anion radical scavenging by riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe2+) chelating activities. Silymarin inhibited 82.7% lipid peroxidation of linoleic acid emulsion at 30 μg/mL concentration; butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox indicated inhibition of 83.3, 82.1, 68.1 and 81.3% on peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, silymarin had an effective DPPH· scavenging, ABTS√+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power by Fe3+ ? Fe2+ transformation, cupric ions (Cu2+) reducing ability by Cuprac method, and ferrous ions (Fe2+) chelating activities. Also, BHA, BHT, α-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. Moreover, this study, which clarifies antioxidant mechanism of silymarin, brings new information on the antioxidant properties of silymarin. According to the present study, silymarin had effective in vitro antioxidant and radical scavenging activity. It could be used in the pharmacological and food industry because of its antioxidant properties.  相似文献   

2.
In this paper, a series of novel bromophenol derivatives were synthesized and evaluated for their acetylcholinesterase and α-glycosidase enzymes inhibition properties and antioxidant activity. Diarylmethanones were synthesized and their bromination was carried out. During bromination, some compounds gave new bromophenols via regioselective O-demethylation. Demethylation of brominated diarylmethanones was also performed with BBr3 to give novel bromophenols. In addition, we examines the antioxidant capacity of novel bromophenol derivatives using several in vitro bioanalytical methodologies such as 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS⋅+) and 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) radical scavenging activity, Fe3+ and Cu2+ reducing activities and ferrous (Fe2+) ions chelating activities. Also, novel bromophenols and methoxylated bromophenols derivatives were tested against acetylcholinesterase and α-glycosidase, which associated with some metabolic diseases. The novel bromophenols showed Ki values in range of 8.94 ± 0.73–59.45 ± 14.97 nM against AChE and 4.31 ± 1.93–44.14 ± 2.19 nM against α-glycosidase.  相似文献   

3.
In the present study, we determined the antioxidant activity of cepharanthine and fangchinoline from Stephania rotunda by performing different in vitro antioxidant assays, including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, N,N- dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging, superoxide anion (O2?–) radical scavenging, hydrogen peroxide scavenging, total antioxidant activity, reducing power, and ferrous ion (Fe2+) chelating activities. Cepharanthine and fangchinoline showed 94.6 and 93.3% inhibition on lipid peroxidation of linoleic acid emulsion at 30 μg/mL concentration, respectively. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol, and trolox indicated inhibitions of 83.3, 92.2, 72.4, and 81.3% on peroxidation of linoleic acid emulsion at the same concentration (30 μg/mL), respectively. According to the results, cepharanthine and fangchinoline have effective antioxidant and radical scavenging activity.  相似文献   

4.
5.
In this study, a series of novel bromophenols were synthesized from benzoic acids and methoxylated bromophenols. The synthesized compounds were evaluated by using different bioanalytical antioxidant assays including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+) radical scavenging assays. Also, reducing power of novel bromophenols were evaluated by Cu2+-Cu+ reducing, Fe3+-Fe2+ reducing and [Fe3+-(TPTZ)2]3+-[Fe2+-(TPTZ)2]2+ reducing and ferrous ions (Fe2+) chelating abilities. The compounds demonstrate powerful antioxidant activities when compared to standard antioxidant molecules of α-tocopherol, trolox, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT). Also in the last part of this studies novel bromophenols were tested against some metabolic enzymes including acetylcholinesterase (AChE), butyrylcholinesterase (BChE) enzymes and carbonic anhydrase I, and II (hCA I and hCA II) isoenzymes. The newly synthesized bromophenols showed Ki values in a range of 6.78 ± 0.68 to 126.07 ± 35.6 nM against hCA I, 4.32 ± 0.23 to 72.25 ± 12.94 nM against hCA II, 4.60 ± 1.15 to 38.13 ± 5.91 nM against AChE and 7.36 ± 1.31 to 29.38 ± 3.68 nM against BChE.  相似文献   

6.
Abstract

The relativeThe relative activities of some hydrogen-donating antioxidants were assessed by comparing their activities with that of Trolox (Trolox equivalent antioxidant capacity, TEAC) for scavenging the ABTS radical cation (ABTS?+) generated in the aqueous phase. We have verified, however, that TEAC values may change with the concentration of compounds and with the measuring times used. Not withstanding, TEAC values do not differ significantly if the compounds have kinetic curves of ABTS?+ formation similar to that of Trolox. This is the case with ascorbic acid, whose TEAC values, determined by using five concentrations at three different measuring times, are very close. For the flavonoids studied (catechin, rutin, naringenin and silibinin) which have kinetic curves of ABTS?+ formation different from that of Trolox, the TEAC values decrease with increasing concentrations of the compounds for each measuring time, and increase with increasing measuring times for each concentration. In the present study, we conclude that, in order to evaluate relative antioxidant activities of compounds by the ABTS assay, it is essential to perform kinetic studies to assess scavenging of ABTS?+ by these compounds. Therefore, when the TEAC values of compounds are determined for more than one measuring time, we may be sure that all the antioxidant potential of compounds is being considered and whether or not it is possible to establish a hierarchy for their antioxidant activities.  相似文献   

7.
8.
9.
The aim of the present study was to examine the antioxidant activity of three Veronica species (Plantaginaceae). The antioxidant potential of various extracts obtained from aerial flowering parts was evaluated by DPPH-free (1,1-diphenyl-2-picrylhydrazyl-free) radical scavenging activity and ferric-reducing antioxidant power assays. Considerable antioxidant activity was observed in the plant samples (FRAP values ranged from 0.97 to 4.85 mmol Fe2+/g, and DPPH IC50 values from 12.58 to 66.34 μg/ml); however, these levels were lower than the activity of the control compound butylated hydroxytoluene (BHT) (FRAP: 10.58 mmol Fe2+/g; DPPH IC50: 9.57 μg/ml). Also, the in vivo antioxidant effects were evaluated in several hepatic antioxidant systems in rats (activities of glutathione peroxidase, glutathione reductase, peroxidase, catalase, xanthine oxidase, glutathione content and level of thiobarbituric acid reactive substances) after treatment with different Veronica extracts, or in combination with carbon tetrachloride (CCl4). Pretreatment with 100 mg/kg b.w. of Veronica extracts inhibited CCl4-induced liver injury by decreasing TBA-RS level, increasing GSH content, and bringing the activities of CAT and Px to control levels. The present study suggests that the extracts analyzed could protect the liver cells from CCl4-induced liver damage by their antioxidative effect on hepatocytes.  相似文献   

10.
In this study, series of novel bromophenol derivatives were synthesized and investigated for their antioxidant and AChE inhibition properties. Novel brominated diarylmethanones were obtained from the acylation reactions of benzoic acids with substituted benzenes. One of the bromodiarylmethanone was synthesized from the bromination of diarylmethanone with molecular bromine. All diarylmethanones were converted into their bromophenol derivatives with BBr3. The antioxidant activities of all synthesized compounds were elucidated by using various bioanalytical assays. Radical scavenging activities of compounds 1024 were evaluated by means of DPPH and ABTS+ scavenging activities. In addition, reducing ability of 1024 were determined by Fe3+, Cu2+, and [Fe3+-(TPTZ)2]3 reducing activities. α-Tocopherol, trolox, BHA, and BHT were used as positive antioxidant and radical scavenger molecules. On the other hand, IC50 values were calculated for DPPH, ABTS+ scavenging, and AChE inhibition effects of novel compounds. The results obtained from the current studies clearly show that novel bromophenol derivatives 2024 have considerable antioxidant, antiradical, and AChE inhibition effects.  相似文献   

11.
Biologically and chemically useful hydrazinoimidazolines were evaluated as antioxidant and antihaemolytic agents. 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH?), galvinoxyl radical (GOR), nitric oxide (NO) and hydrogen peroxide (H2O2) scavenging assays, ferric ions reducing power assay, and ex vivo model of rat erythrocytes exposed to 2,2′-azobis(2-methylpropionamidine)dihydrochloride (AAPH) or H2O2 were used. The most potent DPPH? scavengers proved to be hydrazinoimidazolines 3, 2, and 4, revealing excellent antiradical effects – superior or comparable to that of all antioxidant standards used. Moreover, these molecules showed strong NO neutralising potencies – better to that of ascorbic acid (AA) (3), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) (3 and 2), butylated hydroxytoluene (BHT) (3 and 2), and butylated hydroxyanisole (BHA) (3, 2, and 4). Compound 4 was also effective in GOR scavenging. The excellent scavenger of GOR, NO, and H2O2 proved to be structure 5, with the potency superior or comparable to the majority of antioxidant standards used. In turn, compound 9 was effective in H2O2 and GOR neutralisation. All hydrazinoimidazolines revealed the reducing power that is higher than BHT. Moreover, the protective effects of most test compounds on oxidatively stressed erythrocytes were observed. Some structure–activity relationships were disclosed. A significance of the primary hydrazino group on antioxidant effects was confirmed. The most likely DPPH? and GOR scavenging mechanisms for test compounds were propound. Among all the investigated molecules, hydrazinoimidazolines 5, 3, 2, 4, and 9, due to their excellent or good antiradical activities, can represent promising antioxidant candidates with prospective utility for prevention of diseases related to reactive oxygen/nitrogen species.  相似文献   

12.
Barley is a major crop worldwide. It has been reported that barley seeds have an effect on scavenging ROS. However, little has been known about the functional role of the barley on the inhibition of DNA damage and apoptosis by ROS. In this study, we purified 3,4-dihydroxybenzaldehyde from the barley with silica gel column chromatography and HPLC and then identified it by GC/MS. And we firstly investigated the inhibitory effects of 3,4-dihydroxybenzaldehyde purified from the barley on oxidative DNA damage and apoptosis induced by H2O2, the major mediator of oxidative stress and a potent mutagen. In antioxidant activity assay such as DPPH radical and hydroxyl radical scavenging assay, Fe2+ chelating assay, and intracellular ROS scavenging assay by DCF-DA, 3,4-dihydroxybenzaldehyde was found to scavenge DPPH radical, hydroxyl radical and intracellular ROS. Also it chelated Fe2+. In in vitro oxidative DNA damage assay and the expression level of phospho-H2A.X, it inhibited oxidative DNA damage and its treatment decreased the expression level of phospho-H2A.X. And in oxidative cell death and apoptosis assay via MTT assay and Hoechst 33342 staining, respectively, the treatment of 3,4-dihydroxybenzaldehyde attenuated H2O2-induced cell death and apoptosis. These results suggest that the barley may exert the inhibitory effect on H2O2-induced tumor development by blocking H2O2-induced oxidative DNA damage, cell death and apoptosis.  相似文献   

13.
Fish protein hydrolysates (FPH) from horse mackerel were produced by employing an enzyme mixture of subtilisin and trypsin. The antioxidant activity of fish hydrolysates (DPPH scavenging activity, Fe2+ chelating activity and Fe3+ reducing power) was modelled as a function of the operating conditions for the hydrolysis (i.e. protein concentration, temperature and composition of the enzyme mixture). The antioxidant activities showed different behavior depending on whether their controlling pathway was the transference of electrons/protons (i.e. DPPH scavenging activity and Fe3+ reducing power) or metal chelation. In the first case, the antioxidant activities increased with the decrease of substrate concentration and temperature when pure trypsin (DPPH scavenging activity) or a mixture of enzymes (Fe3+ reducing capacity) was employed. Contrarily, hydrolysates showed higher Fe2+ chelating activities at moderate concentration and high temperature (i.e. 5 g/L and 55 °C) employing solely subtilisin. The conflictive behavior among the antioxidant properties suggested using a multiobjective optimization technique. The ε-constraint method was chosen for this purpose. This approach allows determining the most adequate operational conditions for producing hydrolysate with a specific antioxidant profile which is the first approximation to the production of taylor-made antioxidant hydrolysates.  相似文献   

14.
Apilarnil is 3–7 days old drone larvae. It is an organic bee product known to be rich in protein. In this study, the biological activities of Apilarnil were determined by its antioxidant and enzyme inhibition effects. Antioxidant activities were determined by Fe3+, Cu2+, Fe3+-TPTZ ((2,4,6-tris(2-pyridyl)-s-triazine), reducing ability and 1,1-diphenyl-2-picrylhydrazyl (DPPH⋅) scavenging assays. Also, its enzyme inhibition effects were tested against carbonic anhydrase I and II isoenzymes (hCA I, hCA II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Antioxidant activity of Apilarnil was generally lower than the standard molecules in the applied methods. In DPPH⋅ radical scavenging assay, Apilarnil exhibited higher radical scavenging than some standards. Enzyme inhibition results towards hCA I (IC50: 14.2 μg/mL), hCA II: (IC50: 11.5 μg/mL), AChE (IC50: 22.1 μg/mL), BChE (IC50: 16.1 μg/mL) were calculated. In addition, the quantity of 53 different phytochemical compounds of Apilarnil was determined by a validated method by LC/MS/MS. Compounds with the highest concentrations (mg analyte/g dry extract) were determined as quinic acid (1091.045), fumaric acid (48.714), aconitic acid (47.218), kaempferol (39.946), and quercetin (27.508). As a result, it was determined that Apilarnil had effective antioxidant profile when compared to standard antioxidants.  相似文献   

15.
Summary

We have investigated antioxidant actions of acteoside (ACT) and another natural phenylpropanoid glycoside, cistanoside F (CIS-F) on lipid peroxidation in rat liver mitochondria (RLM) and rat liver mitochondrial lipid (RLML) liposomes induced by Fe2+/ADP. A synthetic ACT analogue, TX-1847, was also examined. Oxygen consumption, the formation of thiobarbituric acid reactive substances (TBARs) and glutathione concentration were determined simultaneously during lipid peroxidation. The radical scavenging activity of the compounds was evaluated by using 1,1-diphenyl-2-picrylhydrazyl. ACT and its analogs produced dose-dependent inhibitions of mitochondrial and liposomal lipid peroxidation (ACT ≈ CIS-F > TX-1847). Their radical scavenging activities were ranked as follows: TX-1847 > ACT > CIS-F. ACT, CIS-F, and TX-1847 spared reduced glutathione (GSH) during mitochondrial lipid peroxidation. The radical scavenging activities of the compounds did not parallel their anti-peroxidative activities. The data are consistent with the idea that the inhibitory activities of phenylpropanoids were primarily due to a radical chain-breaking mechanism. The sugar moieties in ACT and CIS-F, and/or the conformational structure of the compounds, also seem to play an important role in their inhibitory effects on lipid peroxidation.  相似文献   

16.
A series of new di- and polyamine-caffeine analogues were synthesised and characterised by NMR, FT-IR, and MS spectroscopic methods. To access the stability of the investigated caffeine analogues, molecular dynamic simulations were performed in NAMD 2.9 assuming CHARMM36 force field. To evaluate the antioxidant capacity of new compounds, three different antioxidant assays were used, namely 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH?) scavenging activity, ferrous ions (Fe2+) chelating activity, and Fe3+→Fe2+reducing ability. In vitro, the ability of new derivatives to protect human erythrocytes against oxidative haemolysis induced by free radical from 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AAPH) was estimated. The cytotoxic activity was tested using MCF-7 breast cancer cells and human erythrocytes. All compounds showed the antioxidant capacity depending mostly on their ferrous ions chelating activity. In the presence of AAPH, some derivatives were able to effectively inhibit the oxidative haemolysis. Two derivatives, namely 8-(methyl(2-(methylamino)ethyl)-amino)caffeine and 8-(methyl(3-(methylamino)propyl)amino)caffeine, showed cytotoxic activity against MCF-7 breast cancer cells but not against human erythrocytes. Therefore, it is concluded that the selected di- and polyamine caffeine analogues, depending on their chemical structure, were able to minimise the oxidative stress and to inhibit the tumour cell growth. The confirmed antioxidant and cytotoxic properties of some caffeine derivatives make them attractive for potential applications in food or pharmaceutical industries.  相似文献   

17.
Silymarin, a known standardized extract obtained from seeds of Silybum marianum is widely used in treatment of several diseases of varying origin. In the present paper, we clarified the antioxidant activity of silymarin by employing various in vitro antioxidant assay such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH(.)) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by Fe3+ - Fe2+ transformation method and Cuprac assay, superoxide anion radical scavenging by riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe2+) chelating activities. Silymarin inhibited 82.7% lipid peroxidation of linoleic acid emulsion at 30 microg/mL concentration; butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol and trolox indicated inhibition of 83.3, 82.1, 68.1 and 81.3% on peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, silymarin had an effective DPPH(.) scavenging, ABTS(.)+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power by Fe3+-Fe2+ transformation, cupric ions (Cu2+) reducing ability by Cuprac method, and ferrous ions (Fe2+) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. Moreover, this study, which clarifies antioxidant mechanism of silymarin, brings new information on the antioxidant properties of silymarin. According to the present study, silymarin had effective in vitro antioxidant and radical scavenging activity. It could be used in the pharmacological and food industry because of its antioxidant properties.  相似文献   

18.
The antioxidant potencies of chondroitin sulfates (CSs) from shark cartilage, salmon cartilage, bovine trachea, and porcine intestinal mucosa were compared by three representative methods for the measurement of the antioxidant activity; DPPH radical scavenging activity, superoxide radical scavenging activity, and hydroxyl radical scavenging activity. CSs from salmon cartilage and bovine trachea showed higher potency in comparison with CSs from shark cartilage and porcine intestinal mucosa. Next, CS from salmon cartilage chelating with Ca2+, Mg2+, Mn2+, or Zn2+ were prepared, and their antioxidant potencies were compared. CS chelating with Ca2+ or Mg2+ ions showed rather decreased DPPH radical scavenging activity in comparison with CS of H+ form. In contrast, CS chelating with Ca2+ or Mg2+ ion showed remarkably enhanced superoxide radical scavenging activity than CS of H+ or Na+ form. Moreover, CS chelating with divalent metal ions, Ca2+, Mg2+, Mn2+, or Zn2+, showed noticeably higher hydroxyl radical scavenging activity than CS of H+ or Na+ form. The present results revealed that the scavenging activities of, at least, superoxide radical and hydroxyl radical were enhanced by the chelation with divalent metal ions.  相似文献   

19.
The antioxidant activity of some amido-carbonyl oximes containing a C=O and –NH–R adjacent to the oxime group, [Phenyl-C(=O)-C(=N-OH)-N(-H)-Phenyl(-R)] where R= H, 4-chloro, 4-methyl, 4-methoxy, 3,4-dichloro, 3,4-dimethyl, 3-chloro-4-dimethyl, 3-chloro-4-methoxy, naphthyl and an amido-carbonyl dioxime were investigated in vitro by ferric thiocyanate, total reducing power by potassium ferricyanide reduction, 1,1-diphenyl-2- picryl-hydrazyl (DPPH·) free radical scavenging, ferrous ions chelating, superoxide anion radical scavenging and hydrogen peroxide scavenging activity assays. The results indicated that the amido-carbonyl oximes have powerful antioxidant capacity.  相似文献   

20.
Ramalin (γ-glutamyl-N′-(2-hydroxyphenyl)hydrazide), a novel compound, was isolated from the methanol-water extract of the Antarctic lichen Ramalina terebrata by several chromatographic methods. The molecular structure of ramalin was determined by spectroscopic analysis. The experimental data showed that ramalin was five times more potent than commercial butylated hydroxyanisole (BHA) in scavenging 1-diphenyl-2-picryl-hydazil (DPPH) free radicals, 27 times more potent in scavenging 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid free radicals (ABTS+) than the vitamin E analogue, trolox, and 2.5 times more potent than BHT in reducing Fe3+ to Fe2+ ions. Similarly, ramalin was 1.2 times more potent than ascorbic acid in scavenging superoxide radicals and 1.25 times more potent than commercial kojic acid in inhibiting tyrosinase enzyme activity, which ultimately leads to whitening of skin cells. Ramalin showed no or very little cytotoxicity in human keratinocyte and fibroblast cells at its antioxidant concentration. Furthermore, ramalin was assessed to determine its antioxidant activity in vivo. One microgram per milliliter ramalin significantly reduced the released nitric oxide (NO) and 0.125 μg/ml ramalin reduced the produced hydrogen peroxide (H2O2) in LPS (lipopolysaccharide)-stimulated murine macrophage Raw264.7 cells. Considering all the data together, ramalin can be a strong therapeutic candidate for controlling oxidative stress in cells.  相似文献   

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