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 generate unpleasant odors. Long-term use of synthetic antiseptic mouthwashes may cause adverse effects and contribute to bacterial resistance, highlighting the need for safer, natural alternatives. Guava leaves (Psidium guajava L.) are known to contain bioactive compounds such as essential oils, tannins, flavonoids, and saponins with potential antibacterial properties. This study aimed to evaluate the antibacterial activity of ethanolic guava leaf extract against Klebsiella pneumoniae and to assess its potential application as an active ingredient in an anti-halitosis mouthwash formulation. The extract was prepared using ethanol as the solvent, and its antibacterial activity was evaluated in vitro using the agar diffusion method at various concentrations. The results showed that the ethanolic guava leaf extract did not exhibit inhibitory activity against Klebsiella pneumoniae, as indicated by the absence of inhibition zones at all tested concentrations. These findings suggest that, under the conditions of this study, ethanolic guava leaf extract has limited antibacterial effectiveness against Klebsiella pneumoniae and requires further optimization before being considered for anti-halitosis mouthwash development.