Optimization and Formulation of Nanoemulsion Ex-tracts Basil Leaves (Ocimum basilicum L.) and Testing of Anti-Acne...

Acne vulgaris is a common dermatological condition that is often worsened by hot and humid climates, such as those in Indonesia. These conditions promote the growth of Propionibacterium acnes, a bacterium involved in acne pathogenesis. Long-term use of topical antibiotics may lead to resistance, highlighting the need for natural alternatives. This study aimed to formulate and optimize a nanoemulsion of basil leaf extract (Ocimum basilicum L.) and evaluate its antibacterial activity against P. acnes. The nanoemulsion was prepared by spontaneous emulsification using Tween 80 as the surfactant and PEG 400 as the co-surfactant. Optimization was performed using the Box-Behnken Design with Design Expert 13 software, considering pH and transmittance as responses. The optimal formulation contained Tween 80 (41.09 %) and PEG 400 (23.35 %), resulting in a nanoemulsion with a particle size of 13.80 ± 0.36 nm, PDI 0.18 ± 0.04, and zeta potential -20.00 ± 0.80 mV. The formulation showed good physical stability and caused no irritation in animal skin tests. Antibacterial testing showed an inhibition zone diameter of 12.30 ± 0.28 mm, indicating weak activity. These findings suggest that basil leaf extract nanoemulsion has potential as a natural topical alternative for acne treatment.