Phenolic Imidazole Derivatives with Dual Antioxidant/Antifungal Activity: Synthesis and Structure-Activity Relationship

Background: Previous publications show that the addition of a phenolic antioxidant to an antifungal agent, considerably enhances the antifungal activity. Objective: Synthesis of novel compounds combining phenolic units with linear or cyclic nitrogencontaining organic molecules with antioxidant/antifungal activity using methodologies previously developed in the group. Methods: Several N- [1,2-dicyano-2- (arylidenamino) vinyl]-O-alkylformamidoximes 3 were synthesized and cyclized to 4,5-dicyano-N- (N´-alcoxyformimidoyl)-2-arylimidazoles 4 upon reflux in DMF, in the presence of manganese dioxide or to 6-cyano-8-arylpurines 5 when the reagent was refluxed in acetonitrile with an excess of triethylamine. These compounds were tested for their antioxidant activity by cyclic voltammetry, DPPH radical (DPPH•) assay and deoxyribose degradation assay. The minimum inhibitory concentration (MIC) of all compounds was evaluated against two yeast species, Saccharomyces cerevisiae and Candida albicans, and against bacteria Bacillus subtilis (Gram-positive) and Escherichia coli (Gram negative). Their cytotoxicity was evaluated in fibroblasts. Results: Among the synthetised compounds, five presented higher antioxidant activity than reference antioxidant Trolox and from these compounds, four presented antifungal activity without toxic effects in fibroblasts and bacteria. Conclusion: Four novel compounds presented dual antioxidant/antifungal activity at concentrations that are not toxic to bacteria and fibroblasts. The active molecules can be used as an inspiration for further studies in this area.

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New Nitrogen Compounds Coupled to Phenolic Units with Antioxidant and Antifungal Activities: Synthesis and Structure–Activity Relationship

Molecules ◽

10.3390/molecules23102530 ◽

2018 ◽

Vol 23 (10) ◽

pp. 2530 ◽

Cited By ~ 4

Author(s):

Ana Bettencourt ◽

Marián Castro ◽

João Silva ◽

Francisco Fernandes ◽

Olga Coutinho ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Inhibitory Concentration ◽

Yeast Species ◽

Nitrogen Compounds ◽

Dpph Radical ◽

Therapeutic Drugs ◽

Structure Activity ◽

Deoxyribose Degradation ◽

New Compounds ◽

Selection Of

A selection of 1-amino-2-arylidenamine-1,2-(dicyano)ethenes 3 was synthesized and cyclized to 2-aryl-4,5-dicyano-1H-imidazoles 4 upon reflux in ethyl acetate/acetonitrile, in the presence of manganese dioxide. These compounds were tested for their antioxidant capacity by cyclic voltammetry, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and deoxyribose degradation assays. The minimum inhibitory concentration of all compounds was evaluated against two yeast species, Saccharomyces cerevisiae and Candida albicans. Their toxicity was tested in mammal fibroblasts. Among the synthesised compounds, two presented dual antioxidant/antifungal activity without toxic effects in fibroblasts. The new compounds synthesized in this work are potential biochemical tools and/or therapeutic drugs.

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Inclusion Complexes of Concentrated Orange Oils and β-Cyclodextrin: Physicochemical and Biological Characterizations

Molecules ◽

10.3390/molecules25215109 ◽

2020 ◽

Vol 25 (21) ◽

pp. 5109

Author(s):

Cynthia Torres-Alvarez ◽

Sandra Castillo ◽

Eduardo Sánchez-García ◽

Carlos Aguilera González ◽

Sergio Arturo Galindo-Rodríguez ◽

...

Keyword(s):

Antioxidant Activity ◽

Antibacterial Activity ◽

Minimum Inhibitory Concentration ◽

Antifungal Activity ◽

Inclusion Complexes ◽

Inhibitory Concentration ◽

Entrapment Efficiency ◽

Ft Ir ◽

Ir Analysis

Concentrated orange oils (5x, 10x, 20x) are ingredients used in different industries as components of flavors and aromas due to their great organoleptic qualities. This research focuses on the search for alternative uses for their application through encapsulation in inclusion complexes with β-cyclodextrin (β–CD). Inclusion complexes of concentrated orange oils (COEO) and β–CD were developed by the co-precipitated method in ratios of 4:96, 12:88, and 16:84 (w/w, COEO: β–CD). The best powder recovery was in the ratio 16:84 for the three oils, with values between 82% and 84.8%. The 20x oil in relation 12:88 showed the highest entrapment efficiency (89.5%) with 102.3 mg/g of β–CD. The FT-IR analysis may suggest an interaction between the oil and the β–CD. The best antioxidant activity was observed in the ratio 12:88 for the three oils. The antifungal activity was determined for all the inclusion complexes, and the 10x fraction showed the highest inhibition at a concentration of 10 mg/mL in ratios 12:88 and 16:84. Antibacterial activity was determined by the minimum inhibitory concentration (MIC) and was found at a concentration of 1.25 mg/mL in ratios 12:88 and 16:84 for 5x and 20x oils.

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Synthesis and biological activities of some indoline derivatives

Journal of the Serbian Chemical Society ◽

10.2298/jsc0912377r ◽

2009 ◽

Vol 74 (12) ◽

pp. 1377-1387 ◽

Cited By ~ 4

Author(s):

Milind Rode ◽

Sahebrao Rindhe ◽

Bhausaheb Karale

Keyword(s):

Antioxidant Activity ◽

Aromatic Amines ◽

Benzoyl Chloride ◽

Stannous Chloride ◽

Biological Activities ◽

Gram Negative Bacteria ◽

Good Activity ◽

Dpph Assay ◽

Gram Negative

The reaction of indoline with a substituted benzoyl chloride in the presence of K2CO3 in THF gave compound 4. Compound 4 was subjected to chlorosulphonation to obtain compound 5. Condensation of aromatic amines with compound 5 led to the synthesis of indoline derivatives 6(a-f). Similarly, 5-nitroindoline was treated with a substituted benzoyl chloride to obtain the nitro compound 9, which was reduced using stannous chloride and reacted further with aromatic sulphonyl chloride to obtain the indoline derivatives 11(a-e). These compounds were tested for antibacterial, anti-tuberculosis and antifungal activity. Some of them showed very good activity against some gram-positive and gram negative bacteria, fungal strains and also Mycobacterium tuberculosis. All of the synthesized compounds were subjected to antioxidant activity testing using the in vitro DPPH assay and most of them showed very good activity.

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Chemical Analysis and Antioxidant and Antimicrobial Activity of Essential oils from Artemisia negrei L. against Drug-Resistant Microbes

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/5902851 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Khalid Chebbac ◽

Abdelfattah EL Moussaoui ◽

Mohammed Bourhia ◽

Ahmad Mohammad Salamatullah ◽

Abdulhakeem Alzahrani ◽

...

Keyword(s):

Antioxidant Activity ◽

Antibacterial Activity ◽

Candida Albicans ◽

Antifungal Activity ◽

Gram Negative ◽

E Coli ◽

Phytochemical Composition ◽

Total Antioxidant ◽

Inhibition Zones ◽

Β Carotene

Background. Artemisia negrei L. (A. negrei) is a medicinal and aromatic plant belonging to the family Asteraceae that is more widespread in the folded Middle Atlas Mountains, Morocco. Materials and Methods. This study was run to investigate the phytochemical composition and antioxidant, antibacterial, and antifungal activities of Artemisia negrei L. essential oil. This oil was extracted from the fresh plant material by using the Clevenger apparatus. The phytochemical composition was characterized by GC-MS. The antioxidant activity was evaluated using different methods including DPPH, β-carotene bleaching, and total antioxidant capacity. The antibacterial activity was tested vs. multidrug-resistant bacteria including both Gram-negative and Gram-positive using inhibition zones in agar media and minimum inhibitory concentration (MIC) bioassays. The antifungal activity was conducted on Candida albicans, Aspergillus niger, Aspergillus flavus, and Fusarium oxysporum using a solid medium assay. Results. The chromatographic characterization of essential oils of A. negrei revealed the presence of 34 compounds constituting 99.91% of the total essential oil. The latter was found to have promising antioxidant activity by all bioassays used such as DPPH, β-carotene bleaching, and total antioxidant capacity. The results obtained showed that our plant oils had potent antibacterial activity towards Gram-negative (E. coli 57, E. coli 97, K. pneumonia, and P. aeruginosa) and Gram-positive (S. aureus), so that the maximum inhibition zones and MIC values were around 18–37 mm and 3.25 to 12.5 mg/mL, respectively. The oil also showed antifungal activity towards Candida albicans, Fusarium oxysporum, and Aspergillus Niger except for flavus species. Conclusion. The findings obtained in the work showed that A. negrei can serve as a valuable source of natural compounds that can be used as a new weapon to fight radical damage and resistant microbes.

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ANTIOXIDANT ACTIVITY OF TARENNA POLYCARPA (MIQ.) KOORD. LEAF

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i4.21929 ◽

2018 ◽

Vol 11 (4) ◽

pp. 224

Author(s):

Rika Puspita Sari ◽

Marline Nainggolan ◽

Rosidah Rosidah

Keyword(s):

Antioxidant Activity ◽

Ethyl Acetate ◽

Leaf Extract ◽

Inhibitory Concentration ◽

Ethanol Extract ◽

Ethyl Acetate Fraction ◽

Antioxidant Potential ◽

Hexane Fraction ◽

Dpph Assay

Objective: The objective of this study is to evaluate the antioxidant activity of Tarenna polycarpa (Miq.) koord. Ex Valenton. Leaf extract and fractions.Methods: Antioxidant activity was examined by DPPH method.Results: Ethanol extract, n-hexane fraction, and ethyl acetate fraction with DPPH assay measured as half maximal inhibitory concentration were 55.21, 109.73, and 42.04 μg/mL, respectively.Conclusions: The results reveal that T. polycarpa extract and fractions have strong antioxidant potential. Our further study is to isolate compounds responsible for antioxidant components.

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Antioxidant, antifungal and anticancer activities of se-enriched Pleurotus spp. mycelium extracts

Archives of Biological Sciences ◽

10.2298/abs1404379m ◽

2014 ◽

Vol 66 (4) ◽

pp. 1379-1388 ◽

Cited By ~ 6

Author(s):

Ivan Milovanovic ◽

Mirjana Stajic ◽

Jasmina Cilerdzic ◽

Tatjana Stanojkovic ◽

Aleksandar Knezevic ◽

...

Keyword(s):

Antioxidant Activity ◽

Inhibitory Concentration ◽

Radical Scavenging ◽

Pleurotus Eryngii ◽

Dpph Radical ◽

Anticancer Activities ◽

Radical Scavenging Capacity ◽

Low Concentrations ◽

Scavenging Capacity ◽

Dpph Radical Scavenging

The goal of this study was the evaluation of antifungal, antioxidant and anticancer potentials of Pleurotus eryngii, P. ostreatus and P. pulmonarius mycelial extracts, and the influence of mycelium enrichment with selenium on these activities. Both Se-amended and non-amended extracts showed the same or similar minimal inhibitory concentration for 14 studied micromycetes, while a fungicidal effect was not noted, contrary to ketoconazole, which had inhibitory and fungicidal effects at very low concentrations. Se-non-amended extracts exhibited antioxidant activity, especially at higher concentrations. Selenium enrichment influenced activity, its effects decreasing in P. eryngii and P. pulmonarius, while in P. ostreatus no effect was noted. The DPPH? radical scavenging capacity of the extracts was in direct correlation with their phenol and flavonoid contents. Cytotoxic activity against both HeLa and LS174 cell lines was very low compared with cis-DDP. These features suggest that mycelium should be an object of intensive studies.

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Synthesis and Evaluation of Baylis-Hillman Reaction Derived Imidazole and Triazole Cinnamates as Antifungal Agents

International Journal of Medicinal Chemistry ◽

10.1155/2018/5758076 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8

Author(s):

Grady L. Nelson ◽

Michael J. Williams ◽

Shirisha Jonnalagadda ◽

Mohammad A. Alam ◽

Gautam Mereddy ◽

...

Keyword(s):

Breast Cancer ◽

Minimum Inhibitory Concentration ◽

Antifungal Activity ◽

Breast Cancer Cell Line ◽

Antifungal Agents ◽

Inhibitory Concentration ◽

Cancer Cell Line ◽

Structure Activity ◽

Low Toxicity ◽

Mcf 7

Allylic acetates derived from Baylis-Hillman reaction undergo efficient nucleophilic isomerization with imidazoles and triazoles to provide imidazolylmethyl and triazolylmethyl cinnamates stereoselectively. Antifungal evaluation of these derivatives against Cryptococcus neoformans exhibits good minimum inhibitory concentration values. These compounds exhibit low toxicity in proliferating MCF-7 breast cancer cell line. Structure activity relationship studies indicate that halogenated aromatic derivatives provide better antifungal activity.

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Densely Functionalized 2-methylideneazetidines: Evaluation as Antibacterials

Molecules ◽

10.3390/molecules26133891 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3891

Author(s):

Giovanni Petrillo ◽

Cinzia Tavani ◽

Lara Bianchi ◽

Alice Benzi ◽

Maria Maddalena Cavalluzzi ◽

...

Keyword(s):

Antibacterial Agents ◽

Inhibitory Concentration ◽

General Procedure ◽

Eukaryotic Cells ◽

Gram Negative Bacteria ◽

Pharmacological Profile ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Structure Activity

Twenty-two novel, variously substituted nitroazetidines were designed as both sulfonamide and urethane vinylogs possibly endowed with antimicrobial activity. The compounds under study were obtained following a general procedure recently developed, starting from 4-nitropentadienoates deriving from a common β-nitrothiophenic precursor. While being devoid of any activity against fungi and Gram-negative bacteria, most of the title compounds performed as potent antibacterial agents on Gram-positive bacteria (E. faecalis and three strains of S. aureus), with the most potent congener being the 1-(4-chlorobenzyl)-3-nitro-4-(p-tolyl)azetidine 22, which displayed potency close to that of norfloxacin, the reference antibiotic (minimum inhibitory concentration values 4 and 1–2 μg/mL, respectively). Since 22 combines a relatively efficient activity against Gram-positive bacteria and a cytotoxicity on eucharyotic cells only at 4-times higher concentrations (inhibiting concentration on 50% of the cultured eukaryotic cells: 36 ± 10 μM, MIC: 8.6 μM), it may be considered as a promising hit compound for the development of a new series of antibacterials selectively active on Gram-positive pathogens. The relatively concise synthetic route described herein, based on widely available starting materials, could feed further structure–activity relationship studies, thus allowing for the fine investigation and optimization of the toxico-pharmacological profile.

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Antimicrobial and Antioxidant Activities of Plants from Northeast of Mexico

Evidence-based Complementary and Alternative Medicine ◽

10.1093/ecam/nep127 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 29

Author(s):

Ricardo Salazar-Aranda ◽

Luis Alejandro Pérez-López ◽

Joel López-Arroyo ◽

Blanca Alicia Alanís-Garza ◽

Noemí Waksman de Torres

Keyword(s):

Antioxidant Activity ◽

Inhibitory Concentration ◽

Antioxidant Activities ◽

Scientific Information ◽

Gram Negative Bacteria ◽

Bacterial Strains ◽

Time Activity ◽

Gram Negative ◽

Cyperus Alternifolius ◽

First Time

Traditional medicine has a key role in health care worldwide. Obtaining scientific information about the efficacy and safety of the plants from our region is one of the goals of our research group. In this report, 17 plants were selected and collected in different localities from northeast Mexico. The dried plants were separated into leaves, flowers, fruit, stems, roots and bark. Each part was extracted with methanol, and 39 crude extracts were prepared. The extracts were tested for their antimicrobial activity using three Gram-negative bacterial strains (Pseudomonas aeruginosa,Klebsiella pneumoniaeandAcinetobacter baumannii), three Gram-positive bacterial strains (Enterococcus faecalisand twoStaphylococcus aureusstrains), and seven clinically isolated yeasts (Candida albicans,C. krusei,C. tropicalis,C. parapsilosisandC. glabrata); their antioxidant activity was tested using a DPPH free radical assay. No activity against Gram-negative bacteria was observed with any extract up to the maximum concentration tested, 1000 μg ml−1. We report here for the first time activity ofCeanothus coeruleusagainstS. aureus(flowers, minimal inhibitory concentration (MIC) 125 μg ml−1),C. glabrata(MICs 31.25 μg ml−1) andC. parapsilosis(MICs between 31.25 and 125 μg ml−1);Chrysanctinia mexicanaagainstC. glabrata(MICs 31.25μg ml−1);Colubrina greggiiagainstE. faecalis(MICs 250 μg ml−1) andCordia boissieriagainstC. glabrata(MIC 125μg ml−1). Furthermore, this is the first report about antioxidant activity of extracts fromCeanothus coeruleus,Chrysanctinia mexicana,Colubrina greggiiandCyperus alternifolius. Some correlation could exist between antioxidant activity and antiyeast activity against yeasts in the speciesCeanothus coeruleus,Schinus molle,Colubrina greggiiandCordia boissieri.

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Exopolysaccharides from the Energy Microalga Strain Botryococcus braunii: Purification, Characterization, and Antioxidant Activity

Foods ◽

10.3390/foods11010110 ◽

2022 ◽

Vol 11 (1) ◽

pp. 110

Author(s):

Wei-Nan Wang ◽

Tao Li ◽

Yi Li ◽

Ying Zhang ◽

Hua-Lian Wu ◽

...

Keyword(s):

Antioxidant Activity ◽

Hydroxyl Radicals ◽

Inhibitory Concentration ◽

Deae Cellulose ◽

Botryococcus Braunii ◽

Pyranose Ring ◽

Structure Activity ◽

Potential Applications ◽

Relationship Of ◽

Cellulose Column

Botryococcus braunii, a prestigious energy microalga, has recently received widespread attention because it can secrete large amounts of exopolysaccharides (EPS) with potential applications in food, cosmetics, and nutraceuticals. Unfortunately, the insufficiency of research on the bioactivity and structure–activity relationship of B. braunii EPS has impeded the downstream applications. In the present study, alcohol precipitation, deproteinization, and DEAE-cellulose column chromatography were used to extract and purify B. braunii SCS-1905 EPS. It was found that B. braunii SCS-1905 EPS were high-molecular-weight heteropolysaccharides containing uronic acid (7.43–8.83%), protein (2.30–4.04%), and sulfate groups (1.52–1.95%). Additionally, the EPS primarily comprised galactose (52.34–54.12%), glucose (34.60–35.53%), arabinose (9.41–10.32%), and minor amounts of fucose (1.80–1.99%), with the presence of a pyranose ring linked by a β-configurational glycosidic bond. Notably, the antioxidant activity of crude exopolysaccharides (CEPS) was stronger, and the half maximal inhibitory concentration (IC50) for ABTS and hydroxyl radicals was significantly lower than that of deproteinized exopolysaccharides (DEPS). Overall, this study indicated a potential application of B. braunii SCS-1905 EPS as a natural antioxidant. In summary, B. braunii EPS could be used as a potential feedstock for the production of antioxidant health foods.

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