Synthesis of some novel 3- (4-ethoxyphenyl) -5- (4-substituted) -4,5-dihydro-1H-pyrazole derivatives as potent antioxidant agents

Pyrazolines are the most useful heterocyclic moiety in Pharmaceutical and Chemical fields and as the most potential molecules for the design of new chemical entities. Nitrogen-containing heterocyclic compounds, pyrazolines and their derivatives showed a variety of pharmacological activities, including antioxidant properties. In the present study, eleven novel ethoxylated pyrazoline derivatives were synthesized by condensing chalcones with electron releasingethoxy group at one end and different electron-donating, electron-withdrawing groups in another end with hydrazine hydrate andalcohol. The compounds synthesized were structural elucidated by their spectroscopic studies. All the compounds synthesized were evaluated for their in vitro antioxidant potential by 2,2’-diphenyl-1-picrylhydrazyl (DPPH)and hydrogen peroxide free radical scavenging assay methods.Some of these molecules possess moderate to good antioxidant activitywhen compared to standard ascorbic acid. The compound with methoxy group (EH2) exhibits potent antioxidant activity with IC50 value of 9.02 and 9.44µg/ml in DPPH and hydrogen peroxide assay method respectively and the compound with hydroxy group (EH9) also showed potent antioxidant activity with IC50 value of 12.41 and 14.56µg/ml in DPPH and hydrogen peroxide free radical scavengingassay method respectively when compared to standard. The compounds containing electron-donating substituents were found to be good antioxidantswhen compared to standard ascorbic acid.

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EVALUATION OF ANTIOXIDANT ACTIVITY OF CHLOROPHYLL

Journal of Biomedical and Pharmaceutical Research ◽

10.32553/jbpr.v8i6.676 ◽

2019 ◽

Vol 8 (6) ◽

Author(s):

Dipti Acharya ◽

Umesh Kumar Gilhotra ◽

Ranjan Singh ◽

Himanshu Rajpurohit ◽

Ajay Gar

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Hydrogen Peroxide ◽

Antioxidant Activity ◽

Ascorbic Acid ◽

Antioxidant Properties ◽

Antioxidant Potential ◽

Methanolic Solution ◽

Ic50 Value

Antioxidant play an important role to protect damage caused oxidative stress (OS).Chlorophyll having phenolic contents are reported to possess antioxidant properties. The present study was designed to investigate the antioxidant properties of methanolic solution from Super Chlorophyll. Objective: The main objective of the study was to evaluate the antioxidant activity of the chlorophyll in different validated in vitro models. Methods: The antioxidant activities of methanolic solution were evaluated by in vitro standard method using UV-Spectrophotometer. The antioxidant activity were determined bt total antioxidant capacity, DPPH (1-1-diphennyl-2-picrylhydrzine) radical scavenging assay, Nitric Oxide scavenging assay and Hydrogen Peroxide scavenging assay methods. Result: The solution of Chlorophyll was studied for antioxidant potential. Ascorbic acid was used as standard. This method is simple and activity of the solution is reported in term of IC50 value. Antioxidant properties depend on the IC50 value. Lesser the IC50 value, more is the antioxidant activity. Chlorophyll showed good antioxidant activity. Conclusion: In case of in vitro antioxidant activity, Chlorophyll scavenged DPPH, hydrogen peroxide, nitric oxide radicals significantly, showed IC50 values near to standard ascorbic acid, thus proving to have good antioxidant potential. Keywords: Oxidative stress, DPPH, Antioxidant, Super chlorophyll.

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Phytochemical screening and In-vitro antioxidant activity of Centella asiatica extracts

International Journal of Phytomedicine ◽

10.5138/09750185.2123 ◽

2017 ◽

Vol 9 (4) ◽

pp. 615

Author(s):

Mukesh Kumar Yadav ◽

Santosh Kumar Singh ◽

JS Tripathi ◽

YB Tripathi

Keyword(s):

Hydrogen Peroxide ◽

Antioxidant Activity ◽

Free Radical ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Centella Asiatica ◽

Free Radical Scavenging ◽

Scavenging Activity ◽

Phytochemical Screening

Centella asiatica also known as mandukparni or Indian pennywort or jalbrahmi, which has been used as a medicine in the Ayurveda from ancient times and mentioned in many classical texts of Ayurveda. Centella asiatica has long been used to improve memory and cognitive function.The study aimed to identify the phytochemicals present in different solvent extracts of Centella asiatica (i.e. PECA- Petroleum ether extract of C. asiatica, CCA- Chloroform extract of C. asiatica, EACA- Ethyl acetate extract of C. asiatica, ECA- Ethanolic extract of C. asiatica, HACA- Hydro-alcoholic extract of C. asiatica) and evaluate the respective in-vitro antioxidant potentials. The phytochemical screening of extracts was done with standardized procedures and the antioxidant potential of different solvent extracts of Centella asiatica was assessed by its free radical scavenging activity 2, 2-diphenyl -1- picrylhydrazyl (DPPH) as well as hydrogen peroxide scavenging assay respectively for reducing capability.In all different solvent extracts of C. asiatica revealed excellent free radical scavenging activity as revealed by 2-2- diphenyl-1-picryl-hydrazyl (DPPH) assay with EC50 values for ECA=128.752±1.85 μg/ml, HACA=274.884±1.21 μg/ml and hydrogen peroxide assay against the standard (Butylated hydroxytoluene) BHT, with the EC50 values ECA=429.69±0.92 μg/ml HACA=458.08±0.58 μg/ml while rest solvent extracts shown very less antioxidant activity. The present study indicates that the Centella asiatica extracts have good antioxidant activity which can be used in stress and anxiety and also a good source to be used as natural drugs.

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Synthesis and Antioxidant Properties of Novel 2-(2,4-Dioxothiazolidin-5-ylidene)-Acetamides Containing 1,3,4-Thia/Oxadiazole Moieties

Biointerface Research in Applied Chemistry ◽

10.33263/briac125.67106722 ◽

2021 ◽

Vol 12 (5) ◽

pp. 6710-6722

Keyword(s):

Ascorbic Acid ◽

Acetyl Chloride ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Scavenging Effect ◽

Highly Active ◽

Ethanol Medium ◽

Ic50 Value ◽

Radical Scavenging Ability

A series of novel 1,3,4-thia(oxa)diazole substituted 2-(2,4-dioxothiazolidine-5-ylidene)-acetamides 3a-c, 4 and 5a-k have been synthesized following the acylation reaction of 2-amino-5-aryl-1,3,4-oxadiazoles, 5-amino-1,3,4-thiadiazole-2-thiol and it’s S-alkylated derivatives with 2-(2,4-dioxothiazolidine-5-ylidene)acetyl chloride in dioxane medium. The functionalization of compounds 3b, 3c, 5d and 5e was carried out on their N3 position under N-alkylation conditions with N-aryl-2-chloroacetamides in DMF/ethanol medium yielded the corresponding 2,4-dioxothiazolidine-3,5-diacetic acid diamides 6a-e and 7a-b. The structures of target compounds were confirmed by using 1H NMR spectroscopy and elemental analysis. The antioxidant activity evaluation in vitro of the synthesized compounds was performed by the method of scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. As a result, the highly active compound 4, namely 2-(2,4-dioxothiazolidin-5-ylidene)-N-(5-mercapto-[1,3,4]thiadiazol-2-yl)acetamide was found to be the most efficient candidate among all compounds with a radical scavenging ability of 88.9%, which was comparable that for ascorbic acid (92.7%). The experimentally calculated IC50 value of 43.1 µM for compound 4 was lower than for ascorbic acid (50.5 µM).

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Evaluation of antioxidant activity of Melothria maderaspatana in vitro

Open Life Sciences ◽

10.2478/s11535-010-0005-5 ◽

2010 ◽

Vol 5 (2) ◽

pp. 224-230 ◽

Cited By ~ 7

Author(s):

Boobalan Raja ◽

Kodukkur Pugalendi

Keyword(s):

Hydrogen Peroxide ◽

Antioxidant Activity ◽

Free Radical ◽

Hydroxyl Radical ◽

Superoxide Anion ◽

Radical Scavenging ◽

Reducing Power ◽

Free Radical Scavenging ◽

Melothria Maderaspatana

AbstractIn this study, an aqueous extract of leaves from Melothria maderaspatana was tested for in vitro antioxidant activity. Free radical scavenging assays, such as hydroxyl radical, hydrogen peroxide, superoxide anion radical and 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azinobis-(3-ethyl-enzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power assay, were studied. The extract effectively scavenged hydroxyl radical, hydrogen peroxide and superoxide anion radicals. It also scavenged DPPH and ABTS radicals. Furthermore, it was found to have reducing power. All concentrations of leaf extract exhibited free radical scavenging and antioxidant power, and the preventive effects were in a dose-dependent manner. The antioxidant activities of the above were compared to standard antioxidants such as butylated hydroxytoluene (BHT), ascorbic acid, and α-tocopherol. The results obtained in the present study indicate that the M. maderaspatana extract could be considered a potential source of natural antioxidant.

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Free Radical Scavenging and Antioxidant Activity of Ascorbigen Versus Ascorbic Acid: Studies in Vitro and in Cultured Human Keratinocytes

Journal of Agricultural and Food Chemistry ◽

10.1021/jf802403d ◽

2008 ◽

Vol 56 (24) ◽

pp. 11694-11699 ◽

Cited By ~ 27

Author(s):

Anika E. Wagner ◽

Patricia Huebbe ◽

Tetsuya Konishi ◽

M. Mamunur Rahman ◽

Meiko Nakahara ◽

...

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Radical Scavenging ◽

Human Keratinocytes ◽

Free Radical Scavenging

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Potential Antioxidant Activity of New Tetracyclic and Pentacyclic Nonlinear Phenothiazine Derivatives

Biochemistry Research International ◽

10.1155/2016/9896575 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Godwill Azeh Engwa ◽

Eugene Lekem Ayuk ◽

Benardeth Ujunwa Igbojekwe ◽

Marcellus Unaegbu

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Membrane Damage ◽

The Body ◽

Phenothiazine Derivatives ◽

Antioxidant Agents ◽

Group 3

The global increase in oxidative stress related diseases such as cancer, cardiovascular, and inflammatory diseases caused by overwhelming level of free radicals in the body has encouraged the search for new antioxidant agents. Based on the ability of newly synthesized phenothiazine derivatives (6-chloro-11-azabenzo[a]phenothiazine-5-one and 6-[4-bromophenyl]-10-methyl-11-azabenzo[a]phenothiazine-5-one) to oxidize H2O2, a known free radical to sulfoxide, this study assessed the in vitro and in vivo antioxidant activity. The synthesized phenothiazine derivatives exhibited reducing power potential to convert Fe3+to Fe2+and high ability to scavenge H2O2free radical in vitro. These activities were comparable to ascorbic acid, a standard antioxidant. The catalase activity significantly increased (p<0.05) in groups 1 and 2 animals that received the phenothiazine derivatives compared to the controls (groups 3 and 4) suggesting the ability of the phenothiazine derivatives to scavenge H2O2in vivo. The malondialdehyde level in groups 1 and 2 animals was lower than that in group 3 that received the reference compound (ascorbic acid) and group 4 that received the solvent suggesting the ability of the phenothiazine derivatives to prevent lipid membrane damage. AST and bilirubin levels were higher in group 2 animals which received 6-[4-bromophenyl]-10-methyl-11-azabenzo[a]phenothiazine-5-one compared to group 3, the positive control. The results suggest that phenothiazine derivatives, especially 6-chloro-11-azabenzo[a]phenothiazine-5-one, possess antioxidant activity though 6-[4-bromophenyl]-10-methyl-11-azabenzo[a]phenothiazine-5-one was slightly toxic. This activity may be due to the presence of electron donors such as sulfur as well as the richness of hydrogen in the additional benzene rings for substitution. Further study is needed to identify tolerable doses for possible therapeutic purposes.

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In vitro antioxidant activity of meniran (Phyllantus urinaria) functional drink in human low density lipoprotein (LDL)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/913/1/012093 ◽

2021 ◽

Vol 913 (1) ◽

pp. 012093

Author(s):

U Fitrotin ◽

N Hilmiati ◽

Mardiana ◽

Y Triguna ◽

A Surahman ◽

...

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Phenolic Content ◽

Radical Scavenging Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Density Lipoprotein ◽

Ldl Oxidation ◽

Functional Drink

Abstract Preparation process for meniran (Phillantus urinaria) functional drink (MFD) influences its antioxidant activity. This research aims to understand the phenolic content, DPPH Radical Scavenging Activity (RSA), and LDL oxidation of MFD through various preparation processes. Those preparation processes included soaking fresh meniran (SFM), boiling fresh meniran for 5 minutes (BFM5’), boiling fresh meniran for 10 minutes (BFM10’), and soaking dried meniran (DM). The phenolic content was determined with Folin–Ciocalteu, antioxidant activity was assessed using DPPH and TBARS assay with LDL as the oxidation substrate. An antioxidant references in this research used ascorbic acid. The phenolic content in methods of SFM, BFM5’, BFM10’ and DM were 122±0.022, 182±0.043, 192 ±0.03, and 117 ±0.019 mg GAE/g of meniran respectively. Meanwhile, the DPPH RSA of SFM, BFM5’, BFM10’ and DM accounted for 82.18±0.35, 86.19±0.53, 86.75±0.64 and 69.96% respectively. As comparison, the DPPH RSA of ascorbic acid 50 ppm is 75.65±0.82%. At the same time the optimum inhibition of TBARS formation from BFM5’ and BFM10’ methods were 45.83 % and 48.66%, with MDA concentration in human LDL accounted for 38.30±2.39 and 36.30±1.82 nmol MDA/mg protein, respectively. As comparison, MDA concentration in human LDL added with ascorbic acid 25 ppm accounted for 41.35±2.41 nmol MDA/mg protein. In contrast, the control human LDL was 70.70±2.35 nmol MDA/mg protein. This study concludes that the BFM5’ and BFM10’ methods showed the highest antioxidant properties compared to other methods. All methods showed that MFD extract in concentration more than 25 ppm increased the concentration of MDA in human LDL. Therefore, to produce meniran functional drink in optimum antioxidant properties is best by using BFM5’ and BFM10’ preparation methods in meniran concentration of not more than 25 ppm.

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EVALUATION OF ANTIOXIDANT ACTIVITY OF UNRIPE AEGLE MARMELOS CORR. FRUITS

Journal of Applied Pharmaceutical Sciences and Research ◽

10.31069/japsr.v1i01.13056 ◽

2018 ◽

pp. 4-7

Author(s):

Gupta D ◽

John PP ◽

Kumar P ◽

Jain J

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Radical Scavenging ◽

Stem Bark ◽

Aegle Marmelos ◽

Indian Origin ◽

Ic50 Value ◽

Phytochemical Compounds ◽

Free Radical Scavenging Assay

Aegle marmelos Corr. (Rutaceae), commonly known as Bael, is a tree of Indian origin, well known from ancient period andprescribed for various ailments in Ayurveda. Utilization of bael fruit in day-to-day life has a great nutritional, environmental as well ascommercial importance. Every part of Aegle marmelos including stem, bark, root, leaves, fruit and seeds at all stages of maturity possesmedicinal virtues and has been used in Ethno medicine to exploit its medicinal properties. Objective: This study was undertaken to examine theantioxidant activity of methanolic extract of Aegle marmelos unripe or half ripe fruits. Material and Methods: The antioxidant activity was doneby using DPPH free radical scavenging assay. The IC50 (The concentration of sample required to scavenge 50% of DPPH free radical) wascalculated by plotting graph between % inhibition vs concentration. The ascorbic acid was used as standard antioxidant. Result and Discussion:The IC50 value of extract and ascorbic acid was found to be 62.59μg/ml and 2.80μg/ml. The antioxidant activity found in Aegle marmelos maybe associated with their main phytochemical compounds like flavonoids, phenols and tannins. Conclusion: This activity supports that the fruitcan be used as natural antioxidant to treat free radical induced cellular damages and can also be used as adjuvant with other drugs to givesynergistic effects.

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A Comparative Free Radical Scavenging Evaluation of Amantadine and Rasagiline

Biomedical & Pharmacology Journal ◽

10.13005/bpj/1746 ◽

2019 ◽

Vol 12 (3) ◽

pp. 1175-1179

Author(s):

K. Kranthi ◽

V. V. M. Anand Priya ◽

K. Punnagai ◽

Darling Chellathai David

Keyword(s):

Antioxidant Activity ◽

Free Radical ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Free Radical Scavenging ◽

Intrinsic Activity ◽

Assay Method ◽

Definite Difference ◽

Higher Doses

To evaluated and compare the intrinsic antioxidant ability of amantadine and rasagiline drugs using in-vitro diphenyl-1-picrylhydrazyl assay method. Diphenyl-1-picrylhydrazyl assay method was used to compare the antioxidant activity of rasagiline and amantadine. At lower concentrations (200 - 400 µg/ml), there was a definite difference between amantadine and rasagiline with amantadine showing better antioxidant activity over rasagiline. But at higher doses (600 - 1000 µg/ml) both their antioxidant free radical scavenging activity were comparable. This study proved the intrinsic activity of rasagiline and amantadine which may be beneficial in attenuating the oxidative stress pathways, which were considered responsible for many degenerative diseases.

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FREE RADICAL QUENCHING EFFICACY OF VARIOUS EXTRACTS OF C.PICTUS TO COMBAT OXIDATIVE DAMAGE/STRESS: AN IN VITRO STUDY

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i2.15011 ◽

2017 ◽

Vol 10 (2) ◽

pp. 178

Author(s):

Amala Reddy ◽

Ganesh Venkatayappa

Keyword(s):

Hydrogen Peroxide ◽

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Ethyl Acetate ◽

Antioxidant Activities ◽

Radical Scavenging ◽

Scavenging Activity ◽

Polar Solvents ◽

Standard Drug

Objectives: The objectives of this research article are to elucidate the antioxidant activity of the sequentially extracted fractions using solvents with a varying range of polarity from the leaves of Costus pictus (Zingiberaceae). The antioxidant efficacy to combat the oxidative stress was evaluated based on their superoxide, hydrogen peroxide, and nitric oxide (NO) scavenging activity of the leaf extract.Methods: Extraction was performed by sequential extraction methods with low to high polar solvents. Using hexane as a low polar, dichloromethane as medium polar, and ethyl acetate and methanol as high polar, based on their individual boiling points extraction was carried out. The extracts were then evaporated using a rotary evaporator under vacuum and stored in the dry container. Then, antioxidant activity of each extract was evaluated for superoxide, hydrogen peroxide, and NO scavenging activity, ascorbic acid was used as a standard drug for the study of antioxidant activity. The output was statistically interpreted, and the most significant concentration of the best extract with good antioxidant activity was evaluated.Results: As the methanolic solvent is highly polar and able to retrieve the active lead components from the plant material, was very well correlated with the higher degree of free radical scavenging efficacy. It also exhibited the most and significant inhibition in superoxide radical scavenging, hydrogen peroxide scavenging, and NO scavenging which was about 86±1.23, 94±0.34, and 86±1.87 at 250 µg/ml of extract, respectively. The results from our experiments were in par with the positive control chosen.Conclusions: The above results help us to substantially conclude that bioactive components are extracted well in high polar solvents such as methanol, which mainly includes flavonoids and related polyphenols. These compounds present in C. pictus may be an active lead for potent antioxidant activities which would need further investigations in molecular level.Keywords: Costus pictus, Hexane, Dichloromethane, Ethyl acetate, Methanol, Ascorbic acid.

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