HomeJournal of Interdisciplinary Perspectivesvol. 3 no. 11 (2025)

Determination of the Antibacterial Activity of Clitoria ternatea (Blue ternatea) Flower Ethanolic Extract Against Citrobacter koseri

Raymund J. Capagas | Mary Faustine C. Cabrera | Darylle Alexine D. Grande | Ma. Crisanta J. Guevarra | Roxanne Yllyza O. Kahoday | Jasmine D. Mejos | Mariel Catherine Sedanto | Jeremy Martin | Joey Flores | Chelsea Delos Reyes

Discipline: sciences (non-specific)

 

Abstract:

Citrobacter koseri is a growing pathogenic concern, leading to increased antibiotic resistance and posing a public health threat as standard antibiotics become less effective in treating infections caused by this bacterium. Hence, there is a need to investigate alternative antibacterial agents to mitigate the emergence of resistant strains of Citrobacter koseri. This study utilized Clitoria ternatea, also known as Blue ternatea and Butterfly pea flower, a medicinal plant recognized for its broad-spectrum antimicrobial properties and for containing significant levels of phenolic compounds, flavonoids, and anthocyanins. The study evaluated the antibacterial activity of Clitoria ternatea flower ethanolic extraction in four different concentrations (25%, 50%, 75%, and 100%) against Citrobacter koseri, assessed through the Kirby-Bauer Disk Diffusion Method, comparing the antibacterial activity to the antibiotic Cefazolin. Data were analyzed using zone-of-inhibition measurements and the Kruskal-Wallis test to determine significance. The findings suggested that the 100% concentration of the extract exhibited the largest zone of inhibition, showing a proximate inhibition zone of 22mm, as compared to the antibiotic Cefazolin, which had an average zone of inhibition of 24mm. However, the extract demonstrated resistance to Citrobacter koseri at the lower concentrations. In conclusion, the ethanolic extract of Clitoria ternatea exhibits antibacterial activity against Citrobacter koseri. However, when this plant is combined with antibiotics or other plants with potent antibacterial activity, it can be more effective at combating resistance in Citrobacter koseri.



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