Manuel Aulreck Siville V. Sicalan^1,, Alysa Vianca A. Agpalo¹, Jerleen Tefina R. Meliston¹, Thea Sofia Cassandra A. Pancho¹, Ian Jay P. Saldo¹, Jevoy Gumanyao¹, Mary Jade Peñafiel-Dando¹

Resistance of microorganisms, primarily bacteria, to antimicrobial treatments is a major potential global health risk, especially in developing countries. Investigating and developing new antibacterial agents is crucial to combat this antibacterial-resistant microorganism. T. pandacaqui plants have been known as herbal medicine and are widely distributed in the Philippines, but limited studies have been done on this plant species. Thus, this study aims to conduct phytochemical screening and determine the antibacterial activity of Tabernaemontana pandacaqui Poir. The biologically active constituents of the plant were identified using qualitative phytochemical screening, while the Kirby-Bauer method was used for the antibacterial test. The study's findings indicate that phenols and tannins were only present on the leaves and stem, while triterpenoids were present in all plant parts. The study also found that the T. pandacaqui plant extract exhibited a zone of inhibition for both bacterial strains but mostly against Pseudomonas aeruginosa. The root extracts were observed to have a zone of inhibition against P. aeruginosa in all concentrations for all concentrations (14.8mm at 25mg/ml, 13.8mm at 50mg/ml, 10mm for 75mg/ml, and 11.8 for 100mg/ml) while the leaf (75mg/ml with 10mm) against P. aeruginosa and stem extracts (8mm at 25mg/ml for S. aureus, and 8.8mm at 25mg/ml for P. aeruginosa). The results indicated a statistically significant difference in the stem and root extract's efficacy against P. aeruginosa (p=0.000). The current findings indicate that T. pandacaqui extracts have antimicrobial activity against both bacterial strains but mostly against P. aeruginosa. Additional research is needed to determine the antimicrobial potential of the crude extracts against other infectious agents.

antibacterial activity, pandakaki-puti, phytochemical components, plant extracts, Pseudomonas aeruginosa, Staphylococcus aureus, Tabernaemontana