<![CDATA[Body odor caused by Staphylococcus epidermidis is a common problem, while long-term use of triclosan as an antibiotic carries the risk of resistance and side effects. Therefore, alternatives are needed, such as natural ingredients like basil leaves (Ocimum x africanum L.), which contain bioactive compounds with potential antibacterial properties. This study aimed to formulate a liquid soap containing basil leaf NADES extract and to test its antibacterial activity against Staphylococcus epidermidis. Extraction was performed using the Ultrasound-Assisted Extraction (UAE) method with a NADES solvent of citric acid and sucrose (1:1). The liquid soap was formulated at four extract concentrations: F0 (0%), F1 (9%), F2 (12%), and F3 (15%). Its physical properties were then evaluated, and its antibacterial activity was tested using the disk diffusion method. The results showed that all formulations met the organoleptic requirements, namely: liquid form, pale yellow to golden brown color, and a melon fragrance; pH (6–8); specific gravity (1.011–1.052); viscosity (1,160–3,566 cPs); foam height (22–43 mm); and were homogeneous, except for F3, which was found to be non-homogeneous. All formulations exhibited strong to very strong antibacterial activity with an average inhibition zone of 16.58–22.86 mm, which was higher than that of the positive control (15.23 mm). The results of the One-Way ANOVA test showed significant differences among the liquid soap formulations with a p-value < 0.05, indicating that variations in the concentration of basil leaf NADES extract have a significant effect on the antibacterial activity of the liquid soap. It can therefore be concluded that basil leaf NADES extract can be used to produce liquid soap and provides an antibacterial effect against Staphylococcus epidermidis.]]>
