Plant-based bioactive components have shown immense potential and have recently gained considerable attention. Nevertheless, studies pertaining to betel leaves are scarce. The current study investigated the physio-chemical, antioxidant, and antimicrobial properties of two cultivars of Piper betel named Nadan and Koottakkodinadan. The study also evaluated the effects of ethanolic extract of Koottakkodinadan on the storage stability of the coconut oil at room temperature. Both cultivars contained high amounts of sodium, potassium, calcium, and iron. The bioactive components of betel leaf were extracted using solvents of different polarities. The acetone extract of Koottakkodinadan had the highest phenolic content, (154.3 ± 0.21 mg GAE/g), while the DMSO and dichloromethane extract of Nadan had the highest tannin content (100 ± 0 mg TAE/g) and flavonoid content (37.5 ± 0.2 mg RE/g). Nevertheless, the methanol extract of the Nadan cultivar showed high total antioxidant activity by DPPH and ABTS assay. It also showed significant antimicrobial properties against Staphylococcus aureus. The acetone extract of Koottakkodinadan showed potent antimicrobial effects against E. coli, which could be attributed to phenolic content. The coconut oil storage stability showed promising results when treated with ethanolic extract, emphasizing the significance of betel leaf extracts in the food and pharmaceutical industry.