The Antimicrobial Activity of the Lichen Substances of the Lichens Cladonia Furcata, Ochrolechia Androgyna, Parmelia Caperata and Parmelia Conspresa

ABSTRACT

Antimicrobial activity of fumarprotocetraric acid, lecanoric acid, protocetraric acid and stictic acid isolated from the lichen of Cladonia furcata, Ochrolechia androgyna, Parmelia caperata and Parmelia conspresa was studied in relation to the following species of microorganiosms: Bacillus mycoides, Bacillus subtilis, Staphylococcus aureus, Enterobacter cloaceae, Escherichia coli, Klebsiella pneumoniae, Aspergillus flavus, Aspergillus fumigatus, Botrytis cinerea, Candida albicans, Fusarium oxysporum, Mucor mucedo, Paecilomyces variotii, Penicillium purpurescens, Penicillium verrucosum, Trichoderma harsianum. The antimicrobal activity was estimated by determining the minimal inhibited concentration (MIC) by the Broth tube Dilution method. The researched lichen components ihibited the growth of all the tested microrganisms. The bacterias showed a highrer sensitivity relative to fungi. The lowest MCI value (0.031 mg/mL) was measured for the fumarprotocetraric acid related to the Klebsiella pneumoniae species. The weakest antimicrobial activity was found in stictic acid, which inhibited most of the tested microorganisms at significantly higher concentrations. Generally, all the components had relatively strong antimicrobal activity against the tested microorganisms, among which were the ones that caused deseases in men and animals, which could be of significance for their use for pharmaceutical purposes.

Keywords:

• minimal inhibitory concentration
• antimicrobial activity
• antifungal activity