Ethnopharmacological relevance: Gonorrhea is a sexually transmitted disease (STD), which originates from bacteria, Neisseria gonorrhoeae. It is still one of the major health problems worldwide in both men and women. Many medicinal plants have been recorded in Thai folk medicine for relieving STD but there is no scientific report of these plants for antigonococcal activity.
Aim of the study: This study was conducted to evaluate antigonococcal activity of 22 Thai medicinal plants selected from the plants popularly used in Thai folk medicine for treatment of gonorrhea.
Materials and methods: This study was performed by disc diffusion and agar dilution methods against Neisseria gonorrhoeae. Active compound was investigated by bioautographic assay.
Results: Among the selected plants, Coscinium fenestratum (Gaertn.) Colebr. extract showed the most effective activity against Neisseria gonorrhoeae ATCC 49226 with MIC value of 47.39 microg/ml. Bioautographic assay revealed that berberine was the active compound of Coscinium fenestratum against Neisseria gonorrhoeae. The average MIC values of purified berberine against Neisseria gonorrhoeae ATCC 49226 and 11 clinical isolates were 13.51 and 17.66 microg/ml, respectively while average MIC value of the crude extract of Coscinium fenestratum against all clinical isolates was about 56.39 microg/ml. There was no acute toxicity detected at the dose of 5g of Coscinium fenestratum crude extract per kilogram.
Conclusions: These results provide theoretical support for ethnopharmacological relevance of antigonococcal activity of Coscinium fenestratum and its active compound.