Table 10.
The antibacterial activity of chalcones.
| Compound(s) “Chemical name(s)” | Bacterial species | Study model(s) | Results | Inhibition mechanism | Refs. |
|---|---|---|---|---|---|
| Thiazole-based chalcones “(E)-3-(2-chloro-6-fluorophenylo-1-(2-(ethylamino)- 4–2.1.4.methylthiazol-5-yl)prop-2-en-1-on” | Pseudomonas aeruginosa, MRSA, and Escherichia coli | In vitro, In silico |
MIC: 0.65, 1, 1.3 μmol/mL × 10−2 against E. coli, P. aeruginosa, and MRSA, respectively | Inhibition of DNA gyrase, GyrB, and MurA | [125] |
| “3-(4-Trifluoromethylphenyl)-1-(2-hydroxyphenyl)-2-propen-1-on” “3-(2,6-dimethoxyphenyl)-1-(2-hydroxyphenyl)-2-propen-1-on” “3-(2-methoxyphenyl)-1-(2-hydroxyphenyl)-2-propen-1-on” “3-(4-fluoro-2-methylphenyl)-1-(2-hydroxyphenyl)-2-propen-1-on” |
P. aeruginosa and Acinetobacter baumannii | In vitro | MICs: 100–175 μg/mL | Supported by methoxy and halogen groups | [126] |
| 2′-Hydroxychalcones “(E)-3-(2-hydroxyphenyl)-1-phenylprop-2-en-1-one” | MRSA strains including RN4220, K4414, 1199B, and K2068 | In vitro, In silico |
Binding energies: 6.4, −7.4, −7.0, −7.2, −7.5, and −7.2 kcal/mol |
Inhibition of the NorA efflux pump | [130] |
| Azidosulfonamide chalcones “N-[4-[3-(4-Bromophenyl)acryloyl]phenyl]-4-azidobenzene- sulfonamide” | S. aureus, Micrococcus luteus, Serratia marcescens, Klebsiella pneumoniae, and E. coli | In vitro, In silico |
IZDs: 33 mm and MIC: 1.5 μg/cm3 against S. aureus; IZD: 29 mm and MIC: 1.5 μg/cm3 against M. luteus (most active compound) |
Possible inhibition of the microbial DHPS enzyme | [132] |
| Pyrazole-based adamantyl chalcones “2-(3-((1S,3S)-adamatan-1-yl)-1-(2,4-dinitrophenyl)-4,5-dihydro-1H-pyrazol-5-yl)pyridine” |
P. aeruginosa, E. coli, S. aureus, K. pneumonia, Salmonella typhimurium, and Bacillus subtilis | In vitro | IZDs: 15.3 mm against K. pneumonia (most active compound) | N/A | [37] |
| “(E)-3-(4-fluorophenyl)-1-(2-hydroxyphenyl)prop-2en-1-one” “(E)-1-(2-hydroxyphenyl)-3-(4-ethoxyphenyl)prop-2en-1-one” “(E)-3-(4-(dimethylamino)phenyl)-1-(2-hydroxyphenyl)prop-2-en1-one” “(E)-1-(2-hydroxyphenyl)-3-(thiophen-2-yl)prop-2-en-1-one” |
E. coli ATCC 25922, S. aureus ATCC 25923, and the S. aureus 11999-B strain overexpressing the norA gene | In vitro, In silico |
Significantly reduced the MICs of norfloxacin from 64 to 8 μg/mL | Reduced the resistance to norfloxacin by inhibiting the NorA reflux | [134] |
| 4′-Hydroxy-3-4-dimethoxy-chalcone, 3′-hydroxy-3-acetate, 4-methoxy-chalcone, 3′,4′-dihydroxy, 3,4,4′-trimethoxy-chalcone, and 3,4-dimethoxy-chalcone | SA1199B strain | In vitro | Strengthened the effects of norfloxacin and EtBr against the SA1199-B (norA) strain | Competes with norfloxacin for similar MepA and NorA binding sites | [135] |
| Thiazolyl chalcones “3-(5-[4,5-Dihydro-5-(1H-pyrrol-2-yl)-1H-pyrazol3-yl]-4-methylthiazol-2-yl)pyridine” “4-(4,5-Dihydro-3-[4-methyl-2-(pyridin-3-yl)thiazol-5-yl]-1H-pyrazol-5-yl)pyridine” |
B. subtilis, Shigella flexneri | In vitro | MIC: 0.48 μg/Ml (most active compound) | Results indicate that the effect of pyrazolines derivatives on Gram negative bacterial activity is attributed to its NH group which can act as a hydrogen donor to the target receptor | [136] |
| Trifluoromethyl- and trifluoromethoxy-substituted chalcones “(E)-3-(1”H-indol-3″-yl)-1-[40 -(trifluoromethoxy)phenyl]prop-2-en-1-one” “(E)-3-(1”H-indol-3″-yl)-1-[40 -(trifluoromethyl)phenyl]prop-2-en-1-one” |
S. aureus, B. subtilis, E. coli, and, Proteus vulgaris | In vitro | MIC: 24 μM against B. subtilis and E. coli, MIC: 25 μM against E. coli and P. vulgaris, respectively | N/A | [137] |
| Fluorinated chalcones “(E)-3-(2′-ethoxyphenyl)-1-(4-Fluoro-2-hydroxyphenyl) prop-2-en-1-one” “(E)-3-(3′,4′-diethoxyphenyl)-1-(4-fuoro-2-hydroxyl-ph enyl)prop-2-en-1-one” “(E)-3-(3′,5′-Bis[trifuoromethyl]phenyl)-1-(4-Fluoro- 2-hydroxylphenyl)prop-2-en-1-one” |
MRSA, S. aureus, E. coli, S. pyrogenes, Vancomycin-resistant enterococci, Enterococcus faecalis, Salmonella typhi, Proteus mirabilis, Pseudomonas aeruginosa, Corynebacterium ulcerans | In vitro | IZD: 28 mm against E. coli; 28 mm against MRSA; 28 mm against S. pyrogenes | The electron-releasing group on the B-ring and the fluorine atom on the A-ring enable easy penetration into the negatively charged bacterial wall. | [138] |
IZD: Inhibition zone diameter, MRSA: Methicillin-resistant Staphylococcus aureus, MIC: Minimal inhibitory concentration.