Synthesis, in Vitro Biological Evaluation, and Oxidative Transformation of New Flavonol Derivatives: The Possible Role of the Phenyl-N,N-Dimethylamino Group

Six new flavonols (6a–f) were synthesized with Claisen–Schmidt and Suzuki reactions and they were fully characterized by spectroscopic methods. In order to evaluate their antioxidant activities, their oxygen radical absorption capacity and ferric reducing antioxidant power were measured, along with their free radical scavenging activity against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and 2,2-diphenyl-1-picrylhydrazylradicals. In addition, their cytotoxicity on H9c2 cardiomyoblast cells was also assessed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Compounds bearing the phenyl-N,N-dimethylamino group (6a, 6c, and 6e) exhibited promising antioxidant potency and did not have any cytotoxic effect. After a consideration of these data, the oxidative transformation of the 6c compound was investigated in vitro with a chemical Fenton reaction and the identification of the formed oxidation products was performed by mass spectrometry. Two potential metabolites were detected. Based on these results, compound 6c can be a model compound for future developments. Overall, this work has proved the involvement of the phenyl-N,N-dimethylamino group in the antioxidant activity of flavonols.

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Antioxidant and Anti-Inflammatory Activities of Six Flavonoids from Smilax glabra Roxb

Molecules ◽

10.3390/molecules25225295 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5295

Author(s):

Xinyu Zhao ◽

Ruyi Chen ◽

Yueyue Shi ◽

Xiaoxi Zhang ◽

Chongmei Tian ◽

...

Keyword(s):

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Raw264.7 Cells ◽

Enzyme Linked Immunosorbent Assay ◽

Preparative Hplc ◽

Antioxidant Power ◽

Ferric Reducing Antioxidant Power ◽

Anti Inflammatory

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, 1H NMR and 13C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (−)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS+) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1β, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (−)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS+ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1β, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra.

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Estimation of Cholinesterase Inhibitory and Antioxidant Effects of the Leaf Extracts of Anatolian Ficus carica var. domestica and their Total Phenol and Flavonoid Contents

Natural Product Communications ◽

10.1177/1934578x1100600315 ◽

2011 ◽

Vol 6 (3) ◽

pp. 1934578X1100600 ◽

Cited By ~ 2

Author(s):

Ilkay Erdogan Orhan ◽

Osman Üstün ◽

Bilge Şener

Keyword(s):

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Chloroform Extract ◽

Total Phenol ◽

Ficus Carica ◽

Cholinesterase Inhibition ◽

Leaf Extracts ◽

Antioxidant Power

Ficus carica var. domestica Tsch. & Rav. (common fig) is widely grown in Turkey and exported for its edible fruits. In this study, the n-hexane, chloroform, acetone, methanol, n-butanol, and water extracts of the leaves of F. carica var. domestica were screened for their cholinesterase inhibitory and antioxidant activities. Cholinesterase inhibition against acetyl- (AChE) and butyrylcholinesterase (BChE) was measured by the spectrophotometric method of Ellman at concentrations of 25, 50, and 100 μg/mL., while antioxidant activity was tested using three in vitro methods; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, metal-chelation capacity, and ferric-reducing antioxidant power (FRAP). Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. Our results revealed that the n-hexane and acetone extracts exerted a notable inhibition against both AChE (62.9±0.9% and 50.8±2.1%, respectively) and BChE (76.9±2.2% and 45.6±1.3%, respectively). However, they had low activity in the antioxidant tests. The chloroform extract was found to be the richest in total flavonoid content (252.5±1.1 mg/g quercetin equivalent), while the n-butanol extract had the highest total phenol amount (85.9±3.2 mg/g extract gallic acid equivalent).

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Quinoline Functionalized Schiff Base Silver (I) Complexes: Interactions with Biomolecules and In Vitro Cytotoxicity, Antioxidant and Antimicrobial Activities

Molecules ◽

10.3390/molecules26051205 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1205

Author(s):

Adesola A. Adeleke ◽

Sizwe J. Zamisa ◽

Md. Shahidul Islam ◽

Kolawole Olofinsan ◽

Veronica F. Salau ◽

...

Keyword(s):

Schiff Base ◽

Antioxidant Activities ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Antimicrobial Activities ◽

In Vitro Cytotoxicity ◽

Spectroscopic Techniques ◽

Antioxidant Power

A series of fifteen silver (I) quinoline complexes Q1–Q15 have been synthesized and studied for their biological activities. Q1–Q15 were synthesized from the reactions of quinolinyl Schiff base derivatives L1–L5 (obtained by condensing 2-quinolinecarboxaldehyde with various aniline derivatives) with AgNO3, AgClO4 and AgCF3SO3. Q1–Q15 were characterized by various spectroscopic techniques and the structures of [Ag(L1)2]NO3Q1, [Ag(L1)2]ClO4Q6, [Ag(L2)2]ClO4Q7, [Ag(L2)2]CF3SO3Q12 and [Ag(L4)2]CF3SO3Q14 were unequivocally determined by single crystal X-ray diffraction analysis. In vitro antimicrobial tests against Gram-positive and Gram-negative bacteria revealed the influence of structure and anion on the complexes′ moderate to excellent antibacterial activity. In vitro antioxidant activities of the complexes showed their good radical scavenging activity in ferric reducing antioxidant power (FRAP). Complexes with the fluorine substituent or the thiophene or benzothiazole moieties are more potent with IC50 between 0.95 and 2.22 mg/mL than the standard used, ascorbic acid (2.68 mg/mL). The compounds showed a strong binding affinity with calf thymus-DNA via an intercalation mode and protein through a static quenching mechanism. Cytotoxicity activity was examined against three carcinoma cell lines (HELA, MDA-MB231, and SHSY5Y). [Ag(L2)2]ClO4Q7 with a benzothiazole moiety and [Ag(L4)2]ClO4Q9 with a methyl substituent had excellent cytotoxicity against HELA cells.

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Vacillantins A and B, New Anthrone C-glycosides, and a New Dihydroisocoumarin Glucoside from Aloe vacillans and Its Antioxidant Activities

Plants ◽

10.3390/plants9121632 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1632

Author(s):

Maram Al-Tamimi ◽

Shaza M. Al-Massarani ◽

Ali A. El-Gamal ◽

Omer A. Basudan ◽

Maged S. Abdel-Kader ◽

...

Keyword(s):

High Resolution Mass Spectrometry ◽

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

In Vitro Tests ◽

Antioxidant Power ◽

Nitric Oxide Radical ◽

Ferric Reducing Antioxidant Power ◽

Reported Data

A new dihydroisocoumarin glucoside, vacillanoside (3), and two new anthrone C-glycosides microdantin derivatives; vacillantin A (10) and B (11), together with nine known compounds belonging to the anthraquinone, anthrone and isocoumarin groups were isolated from the leaves of Aloe vacillans. The structures were determined based on spectroscopic evidence including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRESIMS) data, along with comparisons to reported data. The leaves were used to extract compounds with different solvents. The extracts were tested for antioxidant activity with a variety of in vitro tests including 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS•+), ferric reducing antioxidant power assay (FRAP), superoxide, and nitric oxide radical scavenging assays. The dichloromethane fraction was most active, displaying significant free radical scavenging activity. The n-butanol fraction also showed notable activity in all assays. Therefore, these findings support the potential use of A. vacillans leaves as an antioxidant medication due to the presence of polyphenolic compounds.

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In Vitro Antioxidant and Anti-Colon Cancer Activities of Sesamum indicum L. Leaf Extract and Its Major Component, Pedaliin

Foods ◽

10.3390/foods10061216 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1216

Author(s):

Seoyun Kim ◽

Hyiyoung Yang ◽

Hwajin Lee ◽

Jihyeung Ju

Keyword(s):

Colon Cancer ◽

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Hct116 Cell ◽

Radical Scavenging ◽

Sesamum Indicum ◽

Appreciable Amount ◽

Major Constituent ◽

Antioxidant Power

Sesame (Sesamum indicum L.) leaves (SLs) are used as vegetables and traditional medicines in Asian and African countries. We investigated in vitro antioxidant and anti-colon cancer efficacy of ethanol extract of SL (SLE) and its major bioactive component. SLE contained appreciable amount of major classes of antioxidant phytochemicals, such as total polyphenols, total flavonoids, and carotenoids, and correspondingly exhibited antioxidant activities, such as radical scavenging activity and ferric reducing antioxidant power (FRAP). A cell viability assay showed that SLE time- and dose-dependently attenuated the growth of human colon cancer cells, HT29 and HCT116. Flow cytometry analysis showed that SLE increased sub-G1 (in HT29 and HCT116) and G2/M (in HCT116) cell populations, suggesting that the growth inhibition by SLE was due to induction of apoptosis and G2/M cell cycle arrest. Trans-well and wound-healing assays showed that SLE alleviated invasion and migration of HT29 and HCT116 cells in non-cytotoxic conditions. High-performance liquid chromatography analysis revealed that pedaliin (6-hydroxylueolin 7-methyl ether 6-glucoside; pedalitin-6-O-glucoside) was a major constituent of SLE. Moreover, FRAP, growth-inhibitory, anti-invasive, and anti-migratory activities of pedaliin were found. These results demonstrated that SLE possesses in vitro antioxidant and anti-colon cancer activities and that pedaliin is a major component contributing to such activities.

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Biological Activities of Carlina Oxide Isolated from the Roots of Carthamus caeruleus

The Natural Products Journal ◽

10.2174/2210315509666190117152740 ◽

2020 ◽

Vol 10 (2) ◽

pp. 145-152 ◽

Cited By ~ 1

Author(s):

Imane Rihab Mami ◽

Rania Belabbes ◽

Mohammed El Amine Dib ◽

Boufeldja Tabti ◽

Jean Costa ◽

...

Keyword(s):

Antifungal Activity ◽

Essential Oil ◽

Skin Diseases ◽

Antioxidant Activities ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Penicillium Expansum ◽

Natural Food ◽

Antioxidant Power

Background: Carthamus caeruleus belongs to the Asteraceae family. The roots are traditionally used as healing agents. They help to heal burns and treat skin diseases. They are also used against joint inflammation and are very effective against diseases such as irritable bowel syndrome for cancer patients. Objectives: The purpose of this work was i) to study the chemical composition of i) the essential oil and hydrosol extract of Carthamus caeruleus, ii) to isolate the major component of both extracts and iii) to evaluate their antioxidant, antifungal and insecticidal activities. Methods: The essential oil and hydrosol extract obtained from the roots were studied by GC and GC/MS. The antioxidant activities were performed using two different methods i) Radical scavenging activity (DPPH) and ii) the Ferric-Reducing Antioxidant Power (FRAP), using BHT as a positive control. Whereas, the antifungal activity of the essential oil and Carlina oxide was investigated against plant fungi. The fumigation toxicity of C. caeruleus essential oil besides Carlina oxide was evaluated against adults of Bactrocera oleae better known as the olive fly. Results: The essential oil and hydrosol extract were mainly represented by acetylenic compounds such as carline oxide and 13-methoxy carline oxide. Carlina oxide was isolated and identified by 1H and 13C NMR spectroscopic means. The results showed that Carlina oxide presented interesting antioxidant and antifungal properties, while C. caeruleus root essential oil had better insecticidal activity. Furthermore, Carlina oxide has demonstrated promising in vivo antifungal activity to control infection of apples by Penicillium expansum. Conclusion: Carlina oxide can be used as a natural food preservative and alternative to chemical fungicides to protect stored apple against Penicillium expansum.

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Inhibitory Effect of Antidesma bunius Fruit Extract on Carbohydrate Digestive Enzymes Activity and Protein Glycation In Vitro

Antioxidants ◽

10.3390/antiox10010032 ◽

2020 ◽

Vol 10 (1) ◽

pp. 32

Author(s):

Pattamaporn Aksornchu ◽

Netima Chamnansilpa ◽

Sirichai Adisakwattana ◽

Thavaree Thilavech ◽

Charoonsri Choosak ◽

...

Keyword(s):

Antioxidant Activity ◽

Radical Scavenging Activity ◽

Digestive Enzyme ◽

Radical Scavenging ◽

Protein Glycation ◽

Trolox Equivalent Antioxidant Capacity ◽

Fruit Extract ◽

Antioxidant Power ◽

Ic50 Values

Antidesma bunius (L.) spreng (Mamao) is widely distributed in Northeastern Thailand. Antidesma bunius has been reported to contain anthocyanins, which possess antioxidant and antihypertensive actions. However, the antidiabetic and antiglycation activity of Antidesma bunius fruit extract has not yet been reported. In this study, we investigated the inhibitory activity of anthocyanin-enriched fraction of Antidesma bunius fruit extract (ABE) against pancreatic α-amylase, intestinal α-glucosidase (maltase and sucrase), protein glycation, as well as antioxidant activity. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) chromatogram revealed that ABE contained phytochemical compounds such as cyanidin-3-glucoside, delphinidin-3-glucoside, ellagic acid, and myricetin-3-galactoside. ABE inhibited intestinal maltase and sucrase activity with the IC50 values of 0.76 ± 0.02 mg/mL and 1.33 ± 0.03 mg/mL, respectively. Furthermore, ABE (0.25 mg/mL) reduced the formation of fluorescent AGEs and the level of Nε-carboxymethyllysine (Nε-CML) in fructose and glucose-induced protein glycation during four weeks of incubation. During the glycation process, the protein carbonyl and β-amyloid cross structure were decreased by ABE (0.25 mg/mL). In addition, ABE exhibited antioxidant activity through DPPH radical scavenging activity and Trolox equivalent antioxidant capacity (TEAC) with the IC50 values 15.84 ± 0.06 µg/mL and 166.1 ± 2.40 µg/mL, respectively. Meanwhile, ferric reducing antioxidant power (FRAP) showed an EC50 value of 182.22 ± 0.64 µg/mL. The findings suggest that ABE may be a promising agent for inhibiting carbohydrate digestive enzyme activity, reducing monosaccharide-induced protein glycation, and antioxidant activity.

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Synthesis and Biological Activities of Hydroxytyrosol Ester Derivatives

Journal of the chemical society of pakistan ◽

10.52568/000610 ◽

2020 ◽

Vol 42 (1) ◽

pp. 109-109

Author(s):

Hao Zang Hao Zang ◽

Qian Xu Qian Xu ◽

Luyun Zhang Luyun Zhang ◽

Guangqing Xia Guangqing Xia ◽

Jiaming Sun and Junyi Zhu Jiaming Sun and Junyi Zhu

Keyword(s):

Ascorbic Acid ◽

Antioxidant Activities ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Acetylcholinesterase Inhibition ◽

Hydroxyl Group ◽

Scavenging Activity ◽

Antioxidant Power ◽

Better Than

A series of hydroxytyrosol (HT) derivatives were synthesized by modification of alcohol hydroxyl group of HT, twenty-five target compounds were obtained and characterized by NMR and HRMS. The antioxidant activities of those compounds were evaluated in three different assays. Except 3e and 3y, all other compounds demonstrated significant 2,2and#39;-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radical cation scavenging activity ranging from IC50 3.4 to 24.4 μM, which were more potent than L-ascorbic acid (IC50=24.8 μM). Compounds 3b-3d, 3f-3k, 3m-3x were better than Trolox (18.3 M). Moreover, the ferric reducing antioxidant power (FRAP) of all compounds were discovered to be more potent than L-ascorbic acid (40.7 mmol/g), except 3e, all other compounds (141.5-202.1 mmol/g) were better than Trolox (94.7 mmol/g). Compounds 3a-3d, 3f-3j, 3l-3m, 3o, 3q, 3t, 3v-3y exhibited more potent hydroxyl radical scavenging activity (IC50=245.1-475.1 M) than L-ascorbic acid (554.4 M) and Trolox (500.4 M). Compounds 3q, 3t and 3y exhibited more potent -Glucosidase inhibition activity (39.1-52.4 M) than Acarbose (60.9 M). Compounds 3a, 3d, 3f-3m, 3s-3t, 3v-3y showed some acetylcholinesterase inhibition activities, compounds 3a, 3d, 3f-3j, 3l-3m, 3o-3p, 3s-3t, 3w showed some butyrylcholinesterase inhibition activities.

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Phytochemical Screening, Polyphenols Content, Antioxidant Power, and Antibacterial Activity of Herniaria hirsuta from Morocco

The Scientific World JOURNAL ◽

10.1155/2018/7470384 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Kenza Ammor ◽

Dalila Bousta ◽

Sanae Jennan ◽

Bahia Bennani ◽

Abdellah Chaqroune ◽

...

Keyword(s):

Antibacterial Activity ◽

Antioxidant Activities ◽

Radical Scavenging ◽

Reducing Power ◽

Antibacterial Activities ◽

Diffusion Method ◽

Antioxidant Power ◽

Negative Effect ◽

Hydroethanolic Extract

The aim of this study is to investigate in vitro antioxidant and antibacterial activities of the aqueous and hydroethanolic extracts for aerial parts of Herniaria hirsuta. Extracts were screened for their possible antioxidant activities by three tests: DPPH free radical-scavenging, reducing power, and molybdenum systems. The screening of antibacterial activity of extracts was individually evaluated against sixteen bacteria species using a disc diffusion method. Flavonoids, total phenols, and tannins content were performed for both extracts. It shows higher content in the hydroethanolic extract. The hydroethanolic extract showed a significant antioxidant activity for the three methods studies to the aqueous extract, but nonsignificant results compared to the reference (BHT). However, both extracts have negative effect on the strains studies for the antibacterial activity.

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Synthesis and Biological Evaluation of Aminonaphthols Incorporated Indole Derivatives

International Journal of Medicinal Chemistry ◽

10.1155/2014/673206 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Saundane Anand Raghunath ◽

Kirankumar Nandibeoor Mathada

Keyword(s):

Radical Scavenging ◽

Antitubercular Activity ◽

Antimicrobial Activities ◽

Biological Evaluation ◽

Secondary Amines ◽

Anticancer Activities ◽

One Pot ◽

Antioxidant Power ◽

Mic Value

An efficient one pot condensation of naphthols (1), 2,5-disubstituted indole-3-carboxaldehydes (2), and secondary amines (3) has been achieved using dichloromethane as a solvent, stirring at room temperature. Some of the new [(disubstituted amino)(5-substituted 2-phenyl-1H-indol-3-yl)methyl]naphthalene-ols (4) derivatives were prepared in good yields. The significant features of this method are simple work-up procedure, inexpensive nontoxic solvent, shorter reaction times, and excellent product yields. The structures of newly synthesized compounds (4a–r) are confirmed by their elemental analysis, FTIR, 1H and 13C NMR, and mass spectral data. These compounds were screened for their in vitro antioxidant, antimicrobial, antitubercular, and anticancer activities. Among the synthesized compounds (4a–r), the compound 4e exhibited highest activity for radical scavenging and ferric ions reducing antioxidant power activities; compounds 4b, 4h, and 4k showed good metal chelating activity. Compounds 4n and 4q showed excellent antimicrobial activities with MIC value 08 µg/mL against tested strains. Compounds 4h, 4k, 4n, and 4q exhibited promising antitubercular activity with MIC value 12.5 µg/mL. Compounds 4k and 4q exhibited 100% cell lysis at concentration 10 µg/mL against MDA-MB-231 (human adenocarcinoma mammary gland) cell lines.

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