Antimicrobial Activities and Mode of Flavonoid Actions

• Published in: Antibiotics (Basel) Vol. 12; no. 2; p. 225
• Main Authors: Thebti, Amal, Meddeb, Ahmed, Ben Salem, Issam, Bakary, Coulibaly, Ayari, Sami, Rezgui, Farhat, Essafi-Benkhadir, Khadija, Boudabous, Abdellatif, Ouzari, Hadda-Imene
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.01.2023; MDPI
• Subjects: Antibacterial activity; Antibiotics; antifungal activity; Antimicrobial activity; Antimicrobial agents; Bacteria; Bromination; Bromine; Chemical activity; Chemical synthesis; Chlorine; E coli; Evaluation; Flavones; Flavonoids; Gram-negative bacteria; Gram-positive bacteria; Hydrogen; Isoflavones; Medical personnel; Methicillin; Microorganisms; Pathogens; permeabilization; Proteins; Salmonella; Scanning electron microscopy; Staphylococcus aureus; Staphylococcus infections; Strains (organisms); Tunisia; antibacterial activity; flavonoids; antifungal activity; permeabilization
• ISSN: 2079-6382; 2079-6382
• DOI: 10.3390/antibiotics12020225

The emergence of antibiotics-resistant bacteria has been a serious concern for medical professionals over the last decade. Therefore, developing new and effective antimicrobials with modified or different modes of action is a continuing imperative. In this context, our study focuses on evaluating the antimicrobial activity of different chemically synthesized flavonoids (FLAV) to guide the chemical synthesis of effective antimicrobial molecules. A set of 12 synthesized molecules (4 chalcones, 4 flavones and 4 flavanones), bearing substitutions with chlorine and bromine groups at the C6' position and methoxy group at the C4' position of the B-ring were evaluated for antimicrobial activity toward 9 strains of Gram-positive and Gram-negative bacteria and 3 fungal strains. Our findings showed that most tested FLAV exhibited moderate to high antibacterial activity, particularly against with minimum inhibitory concentrations (MIC) between the range of 31.25 and 125 μg/mL and that chalcones were more efficient than flavones and flavanones. The examined compounds were also active against the tested fungi with a strong structure-activity relationship (SAR). Interestingly, leakage measurements of the absorbent material at 260 nm and scanning electron microscopy (SEM) demonstrated that the brominated chalcone induced a significant membrane permeabilization of .