EVALUATION OF THE ANTIBACTERIAL ACTIVITY OF ETHANOLIC GUAVA LEAF (PSIDIUM GUAJAVA L.) EXTRACT AGAINST KLEBSIELLA PNEUMONIAE AND ITS APPLICATION IN ANTI-HALITOSIS MOUTHWASH FORMULATION

Abstrak

Halitosis is a common oral health problem that significantly affects quality of life, primarily due to the activity of bacteria that produce volatile sulfur compounds (VSCs). One opportunistic bacterium implicated in this condition is Klebsiella pneumoniae, which can colonize the oral cavity and contribute to unpleasant oral odor. Long-term use of synthetic antiseptic mouthwashes may cause adverse effects and promote bacterial resistance, highlighting the need for alternative treatments derived from natural products. Guava leaves (Psidium guajava L.) are known to contain bioactive compounds such as essential oils, tannins, flavonoids, and saponins, which are suggested to possess antibacterial properties.This study aimed to evaluate the antibacterial activity of the ethanolic extract of guava leaves against Klebsiella pneumoniae and to assess its potential as an active ingredient in anti-halitosis mouthwash formulations. The extraction was carried out using ethanol as the solvent, and the antibacterial activity was evaluated in vitro using the agar diffusion method at various extract concentrations.The results demonstrated that neither the ethanolic extract of guava leaves nor its mouthwash formulation exhibited antibacterial activity against Klebsiella pneumoniae, as indicated by the absence of inhibition zones at all tested concentrations. Based on these findings, it can be concluded that the ethanolic extract of guava leaves is not effective as an antibacterial agent against Klebsiella pneumoniae and cannot yet be recommended as an active ingredient in mouthwash formulations for halitosis management without further optimization.