Antibacterial activity of face toner combinaton of kenikir leaf extract and aloe vera extract against Propionibacterium acnes bacteria

Kenikir (Cosmos caudatus K) and Aloe vera (Aloe vera) rich in beneficial substances that can potentially be used as acne treatment ingredients due to their antibacterial, antioxidant and anti-inflammatory properties. This study aims to evaluate the physical quality and antibacterial activity of a face toner formulation combining kenikir leaves extract and aloe vera leaves extract against Propionibacterium acnes ATCC 6919. The face toner was assessed for physical quality, including pH, homogeneity, organoleptic properties, viscosity, and irritation potential, followed by antibacterial activity testing using the disk diffusion method. Based on the test results, the physical quality test results of the face toner showed that the product met the requirements for organoleptic properties, pH, viscosity, homogeneity, and did not cause skin irritation. In addition, the toner was also effective in inhibiting bacterial growth, with the best inhibition zone observed in formula F1, which contained a combination of 3% Cosmos caudatus leaf extract and 1% aloe vera leaf extract, resulting in an average inhibition zone diameter of 6.4 mm, categorized as moderate. Keywords: Aloe vera, antibacterial activity, Cosmos caudatus, face toner, Propionibacterium acnes