Innovation and evaluation of Vi-Ca herbal soap from Lagundi (vitex negundo) and Papaya (carica papaya): antibacterial efficacy, sensory acceptability and cost efficiency

The demand for natural, skin-friendly, and cost-effective alternatives to commercial skincare products is steadily increasing due to growing consumer awareness of synthetic chemical risks. However, limited research remains on using Lagundi (Vitex negundo) and Papaya (Carica papaya) in developing antibacterial herbal soap. This study aimed to innovate and develop Vi-Ca Soap, a herbal soap formulated from Lagundi and Papaya. It assessed its antibacterial properties, chemical composition, cost-efficiency, and acceptability among different user groups. Utilizing an experimental research design, the soap was produced in two treatments: scented and unscented. It was evaluated by 60 respondents categorized as teenagers, adults, and beauty experts. Sensory evaluation considered nine criteria, including appearance, cleansing, hardness, lathering, texture, foaming, solubility, moisturizing, and fragrance. Findings showed both variants were rated “Excellent,” particularly in lathering, foaming, and cleansing, though appearance received relatively lower scores, especially from beauty experts. ANOVA revealed significant differences in acceptability across groups for specific attributes such as cleansing, texture, and hardness. Antimicrobial analysis confirmed strong activity of Vi-Ca soap against Staphylococcus aureus but limited effect on Escherichia coli, indicating its primary effectiveness against skin bacteria. The total development cost was ₱7,556.00, mainly spent on raw materials and laboratory testing. The study concludes that Vi-Ca Soap is a promising, highly acceptable, and cost-efficient product. Recommendations include improving the soap’s appearance, texture, and antibacterial strength at lower concentrations, and making it effective against more types of bacteria to boost market appeal and user satisfaction.