Preparation Of Antimicrobial Soap Using Kigelia africana (Sausage Tree)-Extracted Phytochemicals

AbstractBacterial skin infections are prevalent, and the use of synthetic antibacterial agents in commercial soaps has raised concerns about health and environmental impacts. This study explores Kigelia africana-extracted phytochemicals, specifically flavonoid rich extracts, as natural antibacterial agents in soap production. Phytochemical screening, extraction, and antimicrobial susceptibility testing were conducted on leaves, bark and fruit samples collected from Bulawayo, Zimbabwe. The bark sample showed superior effectiveness against Escherichia coli and Staphylococcus aureus. Methanol was used as the preferred extraction solvent due to its superior efficacy in extracting phytochemicals with high antimicrobial activity against E. coli and S. aureus, compared to distilled water and ethanol. The flavonoid rich extracts, extracted with methanol exhibited the highest antimicrobial activity amongst other extracted phytochemicals such as tannins, saponins, and alkaloids, therefore the flavonoid-rich extracts were used to manufacture antimicrobial soap. The manufactured soap not only demonstrated superior antimicrobial activity but also exhibited good skin compatibility, with no irritation observed in a 2-week study involving human volunteers. The manufactured soap outperformed commercial soaps (containing Triclosan and Active silver as synthetic antimicrobial reagents) in all assessed aspects, demonstrating superior antimicrobial activity, pH, foam height, foam retention, and percentage-free alkali. The Single factor ANOVA and Tukey’s Post Hock data analysis results validated the manufactured soap's antimicrobial activity. This research contributes to developing natural, effective, and safer alternatives to synthetic antimicrobial agents, reducing health and environmental risks. The findings suggest Kigelia africana flavonoid crude extracts are a promising source of natural antibacterial agents for soap production, offering a potential solution to the drawbacks of synthetic agents. This study's results have implications for the development of sustainable and eco-friendly antimicrobial products. Keywords Kigelia Africana, Phytochemical extraction, Phytochemicals (flavonoids, saponins, alkaloids and tannins), Phytochemical Qualitative analysis, Percentage yield, antimicrobial activity, Kirby Bauer disc diffusion, antimicrobial soap.