Development and Evaluation of Guava Leaves Powder and Lemon Oil-Based Handwash for Enhanced Antimicrobial Efficacy

This study presents the development and evaluation of a herbal handwash formulated with Psidium guajava (guava) leaf powder and Citrus limon (lemon) essential oil, enhanced with glycerine, xanthan gum, and methyl paraben to improve antimicrobial efficacy, texture, and shelf stability. Sodium lauryl sulfate (SLS) as a surfactant for effective cleansing. Guava leaves are rich in flavonoids and tannins, offering potent antibacterial and antioxidant properties, while lemon oil contributes antimicrobial action and a refreshing aroma. The formulation was prepared by blending guava leaf extract and lemon oil into a base containing glycerine for skin moisturization, xanthan gum as a natural thickening agent, and methyl paraben as a preservative. The handwash was evaluated for physicochemical properties, antimicrobial activity against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli, skin compatibility, and product stability. Results demonstrated notable microbial inhibition, a smooth and consistent texture, and acceptable shelf life with no adverse skin reactions. The integration of natural and synthetic components yielded a handwash that balances efficacy, safety, and user experience. This herbal formulation offers a promising, eco-friendly alternative to synthetic handwashes, supporting public health through improved hygiene and reduced chemical exposure.