Evaluation of Antimicrobial and Anti-Acne Activity of Bixa Orellana Leaf Extract-Based Herbal Gel

The present study was aimed at evaluating the antimicrobial and anti-acne potential of an ethanolic leaf extract of Bixa orellana formulated as a herbal gel. The ethanolic extract was subjected to preliminary phytochemical screening, which revealed the presence of flavonoids, phenolic compounds, glycosides, proteins, carbohydrates, and sterols. Quantitative estimation showed appreciable total phenol and total flavonoid content, indicating strong antioxidant potential. The antioxidant activity of the extract was confirmed by DPPH and nitric oxide radical scavenging assays, which demonstrated concentration-dependent free radical inhibition. Antimicrobial activity against Propionibacterium acnes showed significant zones of inhibition, confirming the antibacterial efficacy of the extract. Herbal gel formulations were prepared and evaluated for physicochemical parameters such as homogeneity, pH, viscosity, spreadability, washability, and extrudability, all of which were found to be satisfactory for topical application. In vivo anti-acne activity was assessed using a heat-killed Propionibacterium acnes induced acne model in rats, where the extract-based gel produced a significant reduction in inflammatory ear thickness in a dose-dependent manner. The 2% extract gel showed comparable efficacy to standard clindamycin gel. The results of the study suggest that Bixa orellana leaf extract-based herbal gel is a promising, safe, and effective alternative for the management of acne vulgaris.