Antibacterial properties of Aloe adigratana and Aloe elegans extracts and their potential applications in shampoo and soap development

Aloe adigratana and Aloe elegans are two Ethiopian plants whose medicinal value has not been extensively documented. This study investigated the antibacterial properties of bioactive extracts from A. adigratana and A. elegans to determine their suitability for use in shampoo and soap formulations. Fresh leaves from both plants were extracted using methanol and distilled water and then subjected to phytochemical screening. The extracts were incorporated into shampoo and soap formulations, and their antibacterial efficacy was tested against Salmonella typhi, Staphylococcus aureus, and Escherichia coli using the disk diffusion method. Statistical analysis was performed using one-way ANOVA and a Tukey post-hoc test. Qualitative analysis confirmed the presence of phenols, anthraquinones, alkaloids, and saponins. The aqueous extract of A. adigratana showed significant antibacterial activity against S. aureus (17 ± 1.50 mm; p ≤ 0.05), outperforming the methanol extract (13.0 ± 2.00 mm). Conversely, the aqueous extract of A. elegans was most effective against E. coli (14.5 ± 0.50 mm). The antibacterial activities of the water and methanol extracts from A. adigratana and A. elegans showed a statistically significant difference against S. aureus (p ≤ 0.05), with inhibition zones of 18 ± 2.00 mm and 15.5 ± 2.50 mm, respectively. Furthermore, the combined water extracts of both species exhibited antibacterial activity against S. aureus (18 ± 2.00 mm and 15.5 ± 2.50 mm inhibition zones). The formulated shampoo and soap exhibited a statistically significant difference (p ≤ 0.05) in antibacterial activity against S. aureus, with inhibition zones of 16.50 ± 1.50 mm and 17.50 ± 1.50 mm, respectively. The shampoo was brown, less transparent, with a pH of 6.50, 50 mm foam volume, 110 s wetting time, 23.5% solid content, good dirt dispersion, and was non-irritating. The formulated soap had a pH of 6.78, 2.5 cm foam height, and 25% total fatty matter. Extracts from A. adigratana and A. elegans exhibit antibacterial potential attributed to their bioactive compounds, highlighting their promise for incorporation into shampoo and soap. However, further phytochemical and structural analyses are required to optimize their application.