Antibacterial Effects of Herbal Extract Shampoo Combined with Synergistic Extracts

Abstract

This study aimed to develop an herbal shampoo formulation incorporating crude extracts from Cassia alata, Curcuma longa, Lawsonia inermis, Rhinacanthus nasutus, and Sapindus emarginatus and to evaluate their synergistic antibacterial effects. The extracts were tested against Pseudomonas aeruginosa TISTR 1467, Staphylococcus aureus TISTR 118, and Staphylococcus epidermidis TISTR 1845. The most antibacterial activity shampoo against Pseudomonas aeruginosa TISTR 1467 and Staphylococcus aureus TISTR 118 is the combination between the ethanol extracts of Lawsonia inermis and Curcuma longa, which show enhanced antibacterial activity from the original formula with a relative inhibitory zone of 4.64 and 4.76, respectively. For Staphylococcus epidermidis TISTR 1845, the most effective antibacterial activity occurred at the combination of the ethanol extracts of Rhinacanthus nasutus and Sapindus emarginatus with a relative inhibitory zone of 4.60.  The Minimum Inhibitory Concentration (MIC) test identified the most effective formulation with a MIC of 10⁻⁸ mg/ml. Stability testing shows a high degree of color change in almost all herbal shampoos after being subjected to elevated temperatures. Additionally, consumer preference evaluations involving 30 participants revealed that a formulation containing Sapindus emarginatus with itself and Curcuma longa received the highest satisfaction scores regarding color, foam, and overall acceptance.