Microbiostatic and Synergistic Actions of Extract of Green Walnut Peel

Abstract

The content of juglone in green walnut peel reach the highest in the period of July to August Juglone, extracts of green walnut peel and tee tree oil were tested in antimicrobial experiments against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. The results demonstrated that extract from green walnut peel, and juglone were microbiostatic for all the tested strains. Distinct synergic effects were observed with mixtures of tee tree oil and extract of green walnut peel. Microbiostatic effects on the four microorganisms was highest with a 1 to 10 ratio of tee tree oil and green walnut peel extracts. This mixture was essentially nontoxic and showed good biocompatibility. There were no irritating reactions observed in the repeated dermal irritation test in rabbits, no allergic reactions in guinea pigs and a very low irritating effect in the vaginal mucosa of rabbits. The mixture is promising for use in medical antibacterial products.