Active substance compounds and antibacterial activity of extract flower and leaves of Plumeria rubra and Plumeria alba against Escherichia coli

摘要

Plumeria alba is known to contain active compounds of alkaloids and saponins that act as antibacterial, while Plumeria rubra has not been widely studied but empirically has been widely used as a medicine. The purpose of this study was to evaluate the content of phenol and saponin active compounds and the antibacterial activity of P. rubra flower and leaves extract, also P. alba leaves extracts. Phenol compounds were analyzed based on the Folin-Ciocalteu reagent, and saponins amounts were determined by measuring absorbance with a spectrophotometer at a wavelength of 544 nm, each of them consisted of three replications. Bacterial activity test was carried out using the paper disc method, each activity test consisted of 3 replications. The research data were analyzed using a completely randomized design. The results showed that the total phenol was significantly higher in P. rubra flower extract (2.96), saponin was significantly higher in P. rubra leaves extract (4.27%). Whereas the best inhibition (clear zone) against E. coli is in P. rubra flower extract (8.33 mm). It can be concluded that the highest phenol active compound was found in P. rubra flower extract, and the highest saponin was found in P. rubra leaf extract. The best clear zone is obtained from P. rubra flower extract.