In vitro antibacterial activity of ethanolic Eugenia uniflora leaf extract and molecular docking study of myricetin as potential antibacterial compound

Putu Ririn Andreani; Ni Kadek Mila Seni Puspita Dewi; Ni Luh Putu Kris Monika Yanti; Syamsun Jaya

doi:10.35814/jifi.v24i2.2162

Authors

Putu Ririn Andreani Department of Pharmacy, Faculty of Pharmacy and Health Sciences, Universitas Pendidikan Nasional, Denpasar, 80244, Indonesia
Ni Kadek Mila Seni Puspita Dewi Department of Pharmacy, Faculty of Pharmacy and Health Sciences, Universitas Pendidikan Nasional, Denpasar, 80244, Indonesia
Ni Luh Putu Kris Monika Yanti Department of Pharmacy, Faculty of Pharmacy and Health Sciences, Universitas Pendidikan Nasional, Denpasar, 80244, Indonesia
Syamsun Jaya Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand

DOI:

https://doi.org/10.35814/jifi.v24i2.2162

Keywords:

Antibacterial activity, Bacillus cereus, Eugenia uniflora, molecular docking

Abstract

Bacillus cereus is an opportunistic foodborne pathogen that frequently contaminates food products and causes diarrheal or emetic food poisoning, making it a continuing concern for food safety. The present study evaluated the antibacterial activity of a 70% ethanolic leaf extract of Eugenia uniflora against B. cereus while exploring its possible mechanism of action through molecular docking. Leaf extraction was carried out by maceration with 70% ethanol, followed by phytochemical screening to determine the major secondary metabolites. Antibacterial activity was assessed using the disk diffusion method with extract concentrations of 30%, 40%, and 50%. Phytochemical analysis identified flavonoids, tannins, saponins, steroids, and triterpenoids in the extract. Growth inhibition of B. cereus was observed at all tested concentrations, with inhibition zones ranging from 6.96±0.45 mm to 7.70±0.23 mm, while azithromycin 1% as the positive control showed a higher inhibition zone of 13.70±0.31 mm. Docking analysis further demonstrated that myricetin exhibited favorable binding toward phosphatidylinositol-specific phospholipase C (PI-PLC) from B. cereus (PDB ID: 1GYM), with a predicted binding affinity of −7.8 kcal/mol, suggesting a potential molecular basis for the observed antibacterial activity. Overall, these findings highlight the promise of E. uniflora leaves as a natural source of antibacterial compounds against B. cereus, although additional experimental studies are required to validate the proposed mechanism and confirm the activity of individual phytochemicals through in vitro and in vivo investigations.

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