<![CDATA[Essential oils from rose and ylang-ylang flowers contain volatile compounds that have the potential to provide antimicrobial efficacy. This potential forms the basis for their use as natural active ingredients in the formulation of transparent bar soap. The essential oils used were obtained from rose and ylang-ylang flowers via steam distillation. This study aimed to determine the quality of the transparent solid soap base in accordance with SNI 3532:2021, as well as the antimicrobial efficacy of the transparent solid soap containing rose and ylang-ylang essential oils against Candida albicans and Escherichia coli. Quality testing was conducted in accordance with SNI 3532:2021, while antimicrobial efficacy testing against C. albicans was conducted in accordance with SNI EN 1650:2019 and against E. coli in accordance with SNI EN 1276:2019. The quality test results showed that the transparent solid soap base met the pH parameter of 9.624, had 1.545% ethanol-insoluble matter, a total plate count of <10 colonies/g, a mold and yeast count of <10 colonies/g, and was free of Pseudomonas aeruginosa, Staphylococcus aureus, and C. albicans. The transparent solid soap containing rose essential oil demonstrated bactericidal efficacy against E. coli with a 99.999% reduction, a log reduction of 5.53 under clean conditions and 5.03 under dirty conditions with a contact time of 60 seconds; however, it did not demonstrate efficacy that met the criteria against C. albicans. The transparent solid soap containing ylang-ylang essential oil did not demonstrate efficacy that met the criteria against either of the test microorganisms.]]>
