Formulation and characterization of antibacterial gel containing ethanol extract of oil palm leaves <i>(Elaeis guineensis Jacq.)</i>

Purpose: To develop and characterize a gel formulation of ethanol extract from oil palm leaves as a treatment substitute for acne by preventing the growth of Staphylococcus epidermidis and Propionibacterium acne. Methods: Gel formulations were prepared with 1 % (F1), 3 % (F2), and 5 % (F3) extract concentrations, and their physical properties, 12-week stability, skin irritability on volunteers, and antibacterial efficacy against Propionibacterium acnes and Staphylococcus epidermidis were investigated. Results: The ethanol extract of oil palm leaves exhibited antibacterial activity, with minimum inhibitory concentration (MIC) of 0.10 mg/mL and inhibition zones of 7.23 mm against Propionibacterium acnes and 7.00 mm against Staphylococcus epidermidis. The formulated gel was homogeneous and stable for 12 weeks, had a pH of 5.0 – 6.2, and a viscosity of 2400 – 3400 cps with no incidence of skin irritation. Gel formulations with 1, 3, and 5 % extract showed inhibition zones of 12.00, 11.20, and 10.40 mm against P. acnes, and 11.60, 10.77, and 9.61 mm against Staphylococcus aureus, respectively. Conclusion: Gel formulations containing 3 % (F2) and 5 % (F3) ethanol extract of oil palm leaves, respectively, demonstrate potent antibacterial activity against Propionibacterium acnes and Staphylococcus epidermidis. Further studies, including clinical investigations, may be required to assess the treatment efficacy of the formulations in vivo.