The aim of the present study is to investigate the antioxidant properties of the lichen Cetraria aculeata. Antioxidant activity of the methanol and ethyl acetate extracts of lichen was tested by different methods including determination of total phenolics content, determination of total antioxidant capacity, DPPH free radical scavenging activity, inhibitory activity towards lipid peroxidation, ferrous ion chelating ability and hydroxyl radical scavenging activity. The extracts of the lichen C. aculeata showed significant antioxidant activity. The methanol extract showed higher values for total phenolics and total antioxidant capacity compared to the ethyl acetate extract, while the ethyl acetate extract demonstrated better results for DPPH radical scavenging, inhibitory activity towards lipid peroxidation, chelating ability and hydroxyl radical scavenging than the methanol extract. This is the first report of the antioxidant properties of Cetraria aculeata growing in Serbia. The results of antioxidant activity indicate the application of this lichen as source of natural antioxidants that could be used as a possible food supplement, in the pharmaceutical industry and in the treatment of various diseases.

Senna (Cassia angustifolia Vahl.) is used in food and pharmaceutical technologies as officinal drugs and natural laxative. The aim of the study was to investigate the effect of toluene and methanol Senna extracts on the viability and proliferation of HeLa cells. The senna leaves were extracted in Soxhlet's extractor and obtained toluene and methanolic extracts were used for determination of effects on viability and proliferation. Cytotoxic effect of different concentrations (0.1%, 0.01%, 0.001% and 0.0001%) extracts was investigated in HeLa cells in vitro. MTT test showed significant cytotoxic activity for toluene extract, especially the concentration of 0.1%, while the tested concentrations metanolic extract did not show cytotoxic activity.