Aktivitas Antibakteri Sabun Organik Berbasis Ekstrak Kopi Robusta (Coffea canephora) Terhadap Escherichia coli ATCC 8739

Fatimah Fatimah (Lambung Mangkurat University)
Maya Istyadji
Yudha Irhasyuarna Fatimah

Jurnal Ilmiah BioSmart
Vol. 12 No. 1 (2026): Jurnal Ilmiah BioSmart Volume 12 No. 1 2026

The purpose of this study was to determine the effectiveness of robusta coffee extract-based organic soap (Coffea canephora) against the growth of Escherichia coli ATCC 8739 bacteria. This study used a completely randomized design (CRD) with seven treatment groups of robusta coffee soap at concentrations of 10%, 25%, 50%, 75%, 100%, 150%, and 300%, a positive control (ampicillin), and a negative control (aquadest). The disc diffusion method was used to evaluate antibacterial activity. Data were analyzed using one-way ANOVA and Tukey's post-hoc test. The results showed that the inhibition zone diameter increased with increasing concentration of robusta coffee extract against E. coli. At concentrations ≥150%, the inhibition zone was equivalent to or greater than the positive control ampicillin, with significant differences (p < 0.05). These results suggest that robusta coffee soap has potential as an environmentally friendly natural antibacterial alternative and can promote the use of local robusta coffee.