Metabolite Profiling and Combinatory Antibacterial Potential of Bay Leaf (Sizygium polyanthum) in Inhibiting the Growth of Staphylococcus aureus and Escherichia coli

¹ Department of Medicine, Faculty of Medicine, Universitas Islam Malang (UNISMA), Malang, 65144, Indonesia
² Department of Pharmacy, Faculty of Medicine, Universitas Islam Malang (UNISMA), Malang, 65144, Indonesia
³ Department of Physiology, International Medical School, Management and Science University, Shah Alam 4000. Selangor , Malaysia
⁴ Department of Microbiology and Parasite, Faculty of Medicine, Universitas Islam Malang (UNISMA), Malang, 65144, Indonesia

¹ Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

The use of herbs in combination with antibiotics to treat diseases is a common practice in Indonesian public, and the abundance of bay leaves as a cooking herb and traditional medicine would mean that some interaction with drugs may unintentionally occur. Some herbs with antibiotic activity may interact with antibiotics; however, such interaction with bay leaf extracts is unknown. Bay leaves were extracted using Ultrasonic Assisted Extraction (UAE) for 5, 10, 15, and 20 minutes in ethanol. Total flavonoid and phenol levels was measured quantitatively, and metabolite profile was obtained using LC-HRMS. To determine interaction, an Ameri-Ziaei Dual Antibiotic Synergy Test (AZDAST) protocol was conducted on chloramphenicol against Staphylococcus aureus and Escherichia coli. Extraction for 5 minutes showed the highest yield for phenols and flavonoids (74.291 mg GAE/g and 93.84 mg QE/g), respectively. Metabolite profiling showed 473 bioactive compounds, with eleven active compounds, including resveratrol and vitexin, having the highest concentrations. On both bacteria, bay leaf extract had weak antibacterial activity and no significant difference was found in bay leaf extract combination with chloramphenicol compared to chloramphenicol alone. It was concluded that while bay leaf ethanolic extract contains many compounds with antibacterial activity, it had no interaction with chloramphenicol.