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Updated: May 7, 2026
14:04
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Bactericidal antibiotic-phytochemical combinations against methicillin resistant Staphylococcus aureus.
Bhone Myint Kyaw1, Shuchi Arora, Chu Sing Lim
1School of Mechanical and Aerospace Engineering, Nanyang Technological University , 50 Nanyang Avenue , Singapore 639798.
Summary
Tannic acid and quercetin show synergistic effects when combined with certain antibiotics against methicillin-resistant Staphylococcus aureus (MRSA). These phytochemical-antibiotic combinations offer a promising strategy for combating MRSA infections.
Area of Science:
- Microbiology
- Pharmacology
- Natural Products Chemistry
Background:
- Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant global health threat due to its resistance to conventional antibiotics.
- The emergence of multi-drug resistant MRSA necessitates the exploration of novel therapeutic strategies and compounds.
- Combination therapies involving antibiotics and phytochemicals present a viable approach to enhance antimicrobial efficacy.
Purpose of the Study:
- To evaluate the synergistic and additive effects of six phytochemicals in combination with various antibiotics against MRSA and methicillin-sensitive S. aureus (MSSA).
- To identify effective phytochemical-antibiotic combinations for potential use in treating MRSA infections.
Main Methods:
- Testing the efficacy of six phytochemicals (tannic acid, quercetin, gallic acid ethyl ester, eugenol, menthone, caffeic acid) in combination with selected antibiotics against 12 S. aureus strains.
- Utilizing fractional inhibitory concentration (FIC) index to determine synergistic, additive, or indifferent effects.
- Confirming synergistic combinations through time-kill assays over 24 hours.
Main Results:
- Tannic acid exhibited synergism with fusidic acid, minocycline, cefotaxime, and rifampicin, and additivity with ofloxacin and vancomycin against most strains.
- Quercetin demonstrated synergism with minocycline, fusidic acid, and rifampicin against most strains.
- Gallic acid ethyl ester showed additivity with most antibiotics, while eugenol, menthone, and caffeic acid displayed indifferent effects. No antagonistic interactions were observed.
- FIC index results were confirmed by time-kill assays with 92% accuracy, showing effectiveness over 24 hours.
Conclusions:
- Tannic acid and quercetin are effective phytochemicals for combination therapy against MRSA when paired with specific antibiotics.
- These phytochemical-antibiotic combinations demonstrate synergistic or additive effects, offering a promising strategy to overcome antibiotic resistance.
- The findings support the potential incorporation of these phytochemicals into therapeutic regimens for managing MRSA infections.
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