Antimicrobial activity of some lichens and their components

摘要

Antibacterial and antifungal activity of the acetone, methanol and aqueous extracts of the lichens Lecanora frustulosa and Parmeliopsis hyperopta and their divaricatic acid and zeorin constituents has been screened in vitro against the following species of microorganisms: Bacillus mycoides, Bacillus subtilis, Staphylococcus aureus, Enterobacter cloaceae, Escerichia coli, Klebsiella pneumoniae, Aspergillus flavus, Aspergillus fumigatus, Botrytis cinerea, Candida albicans, Fusahum oxysporum, Mucor mucedo, Paecilomyces variotii, Penicillium purpurescens, Penicillium verrucosum, Trichoderma harsianum. The antimicrobal activity was estimated by the disc-difusion method and determination of the minimal inhibitory concentration (MIC) by the Broth tube Dilution method. The bacteria were more sensitive related to the tested fungi. Acetone and methanol extracts of the investigated lichens showed relatively strong antimicrobial activity, whereas aqueous extracts showed no antimicrobial activity against any of the test organisms. Divaricatic acid and zeorin also showed strong activity against bacteria and fungi. There was no antimicrobial activity against Escerichia coli species. Generally, the tested lichens extracts and lichens compounds demostrated a strong antimicrobial effect against the tested microorganisms. That suggest a possibility of their use in a tretament of various deseases caused by these and similar microorganisms.