scholarly journals Synthesis and characterization of new 4-aryl-2-(2-oxopropoxy)-6-(2,5-dichlorothiophene)nicotinonitrile and their furo[2,3-b]pyridine derivatives: Assessment of antioxidant and biological activity

2018 ◽  
Vol 9 (4) ◽  
pp. 375-381 ◽  
Author(s):  
Mahmoud Al‐Refai ◽  
Mohammad Ibrahim ◽  
Abdullah Al‐Fawwaz ◽  
Armin Geyer
Keyword(s):  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
2D Nmr ◽  
Pyridine Derivatives ◽  
Esi Ms ◽  
Scavenging Effect ◽  
Radical Scavenging Effect ◽  
New Compounds

A new series of furo[2,3-b]pyridine derivatives bearing aryl substituents were synthesized in two steps, where, the cyano-(2H)-pyridones (1a-l) were converted to the corresponding nicotinonitriles (2a-l), followed by the Thorpe-Ziegler ring cyclization to the furo[2,3-b]pyridine derivatives (3a-l). All new compounds were characterized by 1D-NMR experiments (1H and 13C) and 2D-NMR experiments (COSY, HMBC and HSQC), as well as ESI-MS and HR-ESI-MS data. The new compounds were screened for their antioxidant activities by 2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) free radical assay. The highest radical scavenging effect was observed for nicotinonitriles 2d, 2h and 2l and furo[2,3-b]pyridines 3b, 3f and 3j by methanolic solvent at 4.0 mg/mL concentration. Remarkably, all nicotinonitriles and furo[2,3-b]pyridine exhibited a significant radical scavenging activity after 24 and 48 hours compared with 0.5 hour.

In Vitro Antioxidant Activities of Polysaccharides from Auricularia auriada

2011 ◽  
Vol 183-185 ◽  
pp. 104-109
Author(s):  
Ning Zhang ◽  
Zhen Yu Wang ◽  
Hua Zhang ◽  
Jian Ren ◽  
Xiu Mei Hao
Keyword(s):  
Hydrogen Peroxide ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Water Soluble ◽  
Peroxide Radical ◽  
Scavenging Effect ◽  
Radical Scavenging Effect ◽  
Chelating Ability

This study aims to evaluate the antioxidative activities of water and alkaline solution pH=8, 50% ethanolic (APP1 or SAPP1), 75% ethanolic (APP2 or SAPP2) and 100% ethanolic (APP3 or SAPP3) extracts of A. auricular. The antioxidant activities, including the ABTS, superoxide anion radical-scavenging effect, hydrogen peroxide radical-scavenging effect and chelating ability on ferrous ions were studied in vitro. A comparison of the 50% effective concentration (EC50) values of different antioxidative reactions revealed that SAPP3 was more effective in scavenging ABTS, hydrogen peroxide and chelating ability on ferrous ions.SAPP2 showed a higher superoxide radical-scavenging activity. The alkali-soluble polysaccharides extracts showed higher radical-scavenging effect than water-soluble polysaccharides.

scholarly journals Secondary metabolites of Phlebopus species from Northern Thailand

2020 ◽  
Vol 19 (12) ◽  
pp. 1525-1536
Author(s):  
Boontiya Chuankid ◽  
Hedda Schrey ◽  
Benjarong Thongbai ◽  
Olivier Raspé ◽  
Norbert Arnold ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
2D Nmr ◽  
Cytotoxic Activities ◽  
Tumor Cell Lines ◽  
Submerged Cultures ◽  
Esi Ms ◽  
Spectroscopic Analyses ◽  
New Compounds ◽  
Comprehensive Characterization

AbstractSubmerged cultures of the edible mushrooms Phlebopus portentosus and Phlebopus spongiosus were screened for their secondary metabolites by HPLC-UV/Vis and HR-LC-ESI-MS. Two new compounds, 9′-hydroxyphenyl pulvinone (1), containing an unusual pulvinone structure, and phlebopyron (2), together with the seven known pigments, atromentic acid (3), xerocomic acid (4), variegatic acid (5), methyl atromentate (6), methyl isoxerocomate (7), methyl variegatate (8), and variegatorubin (9) were isolated from the cultures. Their structures were assigned on the basis of extensive 1D/2D NMR spectroscopic analyses, as well as HR-ESI-MS, and HR-ESI-MS/MS measurements. Furthermore, the isolated compounds were evaluated for their antimicrobial and cytotoxic properties. 9′-hydroxyphenyl pulvinone (1), xerocomic acid (4), and methyl variegatate (8) exhibited weak to moderate cytotoxic activities against several tumor cell lines. The present paper provides a comprehensive characterization of pigments from the class of pulvinic acids that are present in the basidiomes of many edible bolete species.

scholarly journals Antioxidant activity and polyphenol composition of Pistacia terebinthus fruit from Tessala (Western Algeria)

2021 ◽  
Vol 5 (11) ◽  
pp. 30-34
Author(s):  
Nazim Bellifa ◽  
Abdelhak Ismail Benhaddou ◽  
Houssem Eddine Ferkous ◽  
Mohammed Adil Selka ◽  
Houari Toumi ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Antioxidant Power ◽  
Scavenging Effect ◽  
Coffee Substitute ◽  
Ferric Reducing Antioxidant Power ◽  
Pistacia Terebinthus

Background: Consumption of traditional herbal beverages has been generally increased in the last decades, Terebinth coffee, known as ‘‘menengic coffee’’ in Turkish, is one of the most consumed herbal coffees in Turkey, turpentine tree is one of the components of the Mediterranean bush, particularly in Algeria, known as Betoum el Kiffan is largely used as food and in traditional medicine. Aims: In this study, Total phenol, flavonoid content, and antioxidant activity of three extracts of Pistacia trebinthus fruit growing in Algeria was measured using radical scavenging activity tests and metal-related tests including, ferric-reducing antioxidant power (FRAP). The chemical composition profile of the fruits and the coffee brands was identified by thin-layer chromatography, the effects of roasting method of this fruit was rivaled also. Materials and Methods: The total phenolic content of the extracts was determined using the Folin-Ciocalteu method. All extracts of the terebinth fruits and coffee brands displayed a high DPPH scavenging effect. Results: The results of the ferric-reducing antioxidant power show that the reduction capacity is proportional to the increase in the concentration of the samples. All the extracts of the plant exhibit antioxidant activities lower than those of the reference product besides the infusion extract of the P. terebinthus roasted coffee, which is the most active with an optical density of 1.68 nm at a concentration of 400 μg/mL. The chromatography results show that the various extracts of Pistacia terebinthus fruit carry a large number of polyphenols, in particular the carboxylic acids phenols. Conclusions: The plant can be considered as a coffee substitute and opens up promising avenues for the food and pharmaceutical industry in Algeria. Keywords: Antioxidant, Pistacia terebinthus, Coffee, FRAP, polyphenol.

scholarly journals Radical Scavenging Activities of Novel Cationic Inulin Derivatives

Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1295
Author(s):  
Yuan Chen ◽  
Yingqi Mi ◽  
Jingjing Zhang ◽  
Fang Dong ◽  
Qing Li ◽  
...  
Keyword(s):  
Hydroxyl Radical ◽  
Hydroxyl Radicals ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Synthesis Process ◽  
Scavenging Activity ◽  
Scavenging Effect ◽  
Radical Scavenging Effect ◽  
Ft Ir

Many saccharides are attractive targets for biomaterial applications, due to their abundance, biocompatibility, and biodegradability. In this article, a synthesis process of 6-N-substituted cationic inulin derivatives, including 6-pyridyl-6-deoxyinulin bromide (PIL), 6-(2-amino-pyridyl)-6-deoxyinulin bromide (2APIL), 6-(3-amino-pyridyl)-6-deoxyinulin bromide (3APIL), 6-(4-amino-pyridyl)-6-deoxyinulin bromide (4APIL), 6-(2,3-diamino-pyridyl)-6-deoxyinulin bromide (2,3DAPIL), 6-(3,4-diamino-pyridyl)-6-deoxyinulin bromide (3,4DAPIL), and 6-(2,6-diamino-pyridyl)-6-deoxyinulin bromide (2,6DAPIL) was described. The C6-OH of inulin was first activated by PPh3/N-bromosuccinimide (NBS) bromination. Then, pyridine and different kinds of amino-pyridine groups (different position and different numbers of amino) were grafted onto inulin, respectively, via nucleophilic substitution. Then, we confirmed their structure by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. After this, their radical scavenging activities against hydroxyl radical and diphenylpicryl phenylhydrazine (DPPH) radical were tested in vitro. Each derivative showed a distinct improvement in radical scavenging activity when compared to inulin. The hydroxyl-radical scavenging effect decreased in the following order: 3APIL > PIL > 3,4DAPIL > 4APIL > 2,3DAPIL > 2,6DAPIL > 2APIL. Amongst them, 3APIL revealed the most powerful scavenging effect on hydroxyl radicals, as well as DPPH radicals. At 1.6 mg/mL, it could completely eliminate hydroxyl radicals and could clear 65% of DPPH radicals. The results also showed that the steric hindrance effect and the substitute position of the amino group had an effect on the radical scavenging activity. Moreover, the application prospects of inulin derivatives as natural antioxidant biomaterials are scientifically proven in this paper.

scholarly journals Synthesis of Novel Nitric Oxide Releasing Furoxan Hybrids from Biologically Active Bicyclic Amine and their Antioxidant Activity

2019 ◽  
Vol 31 (8) ◽  
pp. 1724-1728
Author(s):  
P.M. Swami ◽  
P.K. Zubaidha ◽  
G.B. Tiwari
Keyword(s):  
Nitric Oxide ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Biologically Active ◽  
Scavenging Effect ◽  
Antioxidant Agents ◽  
Radical Scavenging Effect ◽  
Nitric Oxide Releasing

The present paper describes the synthesis of novel nitric oxide hybrids obtained by linking bioactive bicyclic amine to substituted furoxans. The antioxidant activities were studied in vitro based on the radical scavenging effect of stable DPPH free radical using ascorbic acid as a standard. The nitric oxide hybrids showed remarkable antioxidant properties and hence, can be employed as potential antioxidant agents.

scholarly journals Comprehensive Fractionation of Antioxidants and GC-MS and ESI-MS Fingerprints of Celastrus hindsii Leaves

Medicines ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 64 ◽  
Author(s):  
Tran Duc Viet ◽  
Tran Dang Xuan ◽  
Truong Mai Van ◽  
Yusuf Andriana ◽  
Ramin Rayee ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Column Chromatography ◽  
Antioxidant Activities ◽  
Southern China ◽  
Biological Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Gas Chromatography Mass Spectrometry ◽  
Ionization Mass ◽  
Esi Ms

Background: In this study, column chromatography was applied to separate active fractions from the ethyl acetate extract of Celastrus hindsii, a medicinal plant widely used in Southern China, Northern Vietnam, Myanmar, and Malaysia. Methods: Fourteen fractions from different dilutions of chloroform and methanol were separated by column chromatography and examined for biological activities. Results: It was found that a dilution of 50–70% methanol in chloroform yielded the highest total phenolics, flavonoids, and antioxidant activities (1,1-dipheny1-2-picrylhydrazyl (DPPH), 2,2-azinobis (3-ehtylbenzothiazoline-6-sulfonic acid), diammonium salt (ABTS) radical scavenging activity, and β-carotene bleaching method measured by lipid peroxidation inhibition). In addition, by gas chromatography-mass spectrometry (GC-MS) and electrospray ionization-mass spectrometry (ESI-MS) analyses, fifteen principal compounds from bioactive fractions belonging to fatty acids, amides, flavonoids, sterols, terpenes, and phenols were identified. Of these compounds, α-amyrin, β-amyrin, hydrazine carboxamide, hexadecanoic acid, fucosterol, (3β)-D:C-friedours-7-en-3-ol, rutin, and 2-hydroxy-1-ethyl ester accounted for maximal quantities, whilst concentrations of other constituents were <5%. Conclusions: It is suggested that these identified compounds may greatly contribute to the antioxidant capacity of C. hindsii as well as its potential pharmaceutical properties.

scholarly journals The isolation, analytical characterization by HPLC-UV and NMR spectroscopy, cytotoxic and antioxidant activities of baeomycesic acid from Thamnolia vermicularis var. subuliformis

2011 ◽  
Vol 65 (5) ◽  
pp. 591-598
Author(s):  
Nedeljko Manojlovic ◽  
Perica Vasiljevic ◽  
Dragan Nikolic ◽  
Gordana Bogdanovic-Dusanovic ◽  
Zoran Markovic ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Herbal Medicines ◽  
Rapid Identification ◽  
Cytotoxic Activities ◽  
Spectroscopic Methods ◽  
Scavenging Activity ◽  
Analytical Characterization

The aim of this work was the analytical characterization of the ?-orcinol depside, baeomycesic acid in lichens extracts. The extract of Thamnolia vermicularis var. subuliformis was analyzed by the two different methods, namely HPLC-UV and 1H NMR analysis. The results showed that baeomycesic acid was the most abundant depside in the lichens. These results could be of use for rapid identification of this metabolite in other lichen species. Besides baeomycesic acid, three depsides and one monocyclic phenolic compound were isolated from the lichen extract on the chromatographic column. The structure of baeomycesic acid was confirmed by HPLC-UV and spectroscopic methods. In addition, antioxidant and cytotoxic activities of baeomycesic acid were determined. The result of the testing showed that baeomycesic acid exhibited a moderate radical scavenging activity (IC50 = 602.10 ? 0.54 ?g/mL) and good cytotoxic activity. This is the first report of detailed analytical characterization, isolation, as well as antioxidant and cytotoxic activities of baeomycesic acid from Thamnolia vermicularis. These results may be helpful in future industrial production of herbal medicines that include this important natural product.

scholarly journals Design, Synthesis and Biological Evaluation of Novel Thiazolidinone Derivatives

2021 ◽  
Vol 33 (10) ◽  
pp. 2379-2385
Author(s):  
Reshma Sathyanarayana ◽  
Boja Poojary ◽  
B. Sukesh Kumar ◽  
Vasantha Kumar ◽  
Rajesh P. Shastry ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Biological Evaluation ◽  
The Novel ◽  
Design Synthesis ◽  
Scavenging Effect ◽  
Elemental Analyses ◽  
Radical Scavenging Effect ◽  
Ft Ir ◽  
Synthesis And Biological Evaluation

In present study, the novel thiazolidinone derivatives were designed and synthesized. The formation of the target compounds was confirmed by the elemental analyses, FT-IR, mass spectroscopy and 1H NMR spectroscopy. These derivatives were subjected to antibacterial and antioxidant activities. The antibacterial results revealed that these derivatives were selectively active against Gram-negative Pseudomonas aeruginosa bacteria. Also, these derivatives displayed a good DPPH radical scavenging effect. Drosophila melanogaster flies were used for evaluating the toxic impact of novel thiazolidinone derivatives.

New Chromene Derivatives with Radical Scavenging Activities from the Brown Alga Sargassum Siliquastrum

2017 ◽  
Vol 41 (2) ◽  
pp. 116-119
Author(s):  
Hahk-Soo Kang ◽  
Jong-Pyung Kim
Keyword(s):  
Brown Algae ◽  
Spectroscopic Data ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
2D Nmr ◽  
Scavenging Activity ◽  
Organic Extract ◽  
Planar Structures ◽  
New Compounds

The organic extract of Sargassum siliquastrum exhibited in vitro radical scavenging activity in our screening of marine brown algae collected in Jeju Island, Korea. Bioactivity-guided fractionation of the organic extract led to the isolation of two new meroterpenoids, named sargachromanols S and T, along with the known meroterpenoids, isopolycerasoidol, nahocol D2, and sargachromanols D, E, G, and I. The planar structures of the new compounds were determined by the analysis of spectroscopic data obtained by HREIMS and 1D and 2D NMR. The structures of the new compounds sargachromanols S and T were closely related to those of previously isolated sargachromanols D and A, respectively. The isolated compounds showed radical scavenging activities in vitro against 1,1-diphenylpicrylhydrazyl and 2,2'-azidobis(3-ethylbenzothiazoline-6-sulfonate) radicals.

scholarly journals Awareness about antioxidant activities of chlorogenic acid among dental students

2020 ◽  
Vol 11 (SPL3) ◽  
pp. 757-759
Author(s):  
Nithyanandham Masilamani ◽  
Dhanraj Ganapathy
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Chlorogenic Acid ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Dental Students ◽  
Free Radical Scavenging ◽  
Scavenging Effect ◽  
Radical Scavenging Effect ◽  
Free Radical Scavenging Effect

Chlorogenic Acid (CA) is the formation of an ester established among caffeic and quinic acid. CA contains hydroxyl based groups over an aromatic moiety and exhibits very effective anticancer, antimutational and antioxidant activities. This survey was performed for assessing the awareness about antioxidant activities of CA amongst dental students. A cross-sectional survey was performed with a pretested questionnaire with ten questions disseminated among 100 dental students. The questionnaire assessed the awareness about CA therapy, their dietary sources, medicinal uses, antioxidant activity, anti ischaemic activity and free radical scavenging effect of chlorogenic acid. The responses were recorded and analyzed. 7% were aware of dietary sources,5% were aware of medical uses, 5% were aware of mechanisms of antioxidant activity, 4 % were aware of the anti ischaemic activity, and 5% were aware of the free radical scavenging effect of chlorogenic acid. Awareness about the usage of CA therapy is very less among dental students. Increased awareness programs and sensitization programs should be conducted to improve the awareness levels.

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