Genotoxic and antigenotoxic potentials of two Usnea species

For ages, lichens have long been investigated popularly for biological roles, mainly antitumor, antimicrobial and antioxidant activities. Many positive results were obtained in these previous research. Thus, in this study, we aimed to determine whether extracts of Usnea articulata (UAE) and Usnea filipendula (UFE) possessing a protection against aflatoxin B1 (AFB1)-induced genotoxic and oxidative damage. The results of our studies showed that 5 μM concentrations of AFB1 increased the frequencies of sister chromatid exchange (SCE) and the level of malondialdehyde (MDA) and decreased the activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx). However, when 5, 10 and 20 µg/mL concentrations of UAE and UFE was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH and GPx level were increased. The Ames (Salmonella typhimurium TA1535, TA1537) and WP2 (Escherichia coli) test systems carried out evinced that UAE and UFE possess any mutagenicity, but have antimutagenic effects. Consequently, the results of this experiment have clearly shown that UAE and UFE have strong antioxidative and antigenotoxic effects that are associated with its antioxidant nature. A detailed study can be performed to determine the antioxidant properties of each compound that will extend the use of lichen extracts in food and pharmacy industries.