Research background. Brain cancer is known to be one of the most difficult types of cancer to be cure. It has serious impact on the lives of diagnosed people due to the insufficient treatment options and their side effects. Thus, the search for novel alternative treatments is ongoing. Melocan (Smilax excelsa L.) and Galdirik (Trachystemon orientalis) are significant contributors to both traditional culinary culture and traditional medicine around Black Sea; however, the evidence regarding their antioxidative and cytotoxic effects remains fairly limited.
Experimental approach. This study aimed to determine the antioxidant and cytotoxic activity of Smilax excelsa and Trachystemon orientalis, on the C6 glioblastoma cell line. Smilax excelsa and Trachystemon orientalis plants were dried and extracted; then, the total phenolic content (TPC) and their phenolic profiles were studied. In addition, their Total Antioxidant Status (TAS) and Total Oxidant Status (TOS) were determined by using an assay kit. We also analyzed the total antioxidant activity (TAA) using the DPPH radical scavenging assay and the cytotoxic impact on the glioma cells via the 3-(4,5-dimethylthiazol-2 yl)-2,5-diphenyltetrazolium (MTT) assay.
Results and conclusions. According to the results, the water extracts of both Smilax excelsa (1158.17 mg gallic acid eq./100 g DM) and Trachystemon orientalis (262 mg gallic acid eq./0 g DM) had higher TPC than the ethanol extracts. TAA were measured as 192.86 mg and 131.92 Trolox eq./100 g DM for the Smilax excels and Trachystemon orientalis, respectively. The MTT assay revealed that Trachystemon orientalis had a greater cytotoxic effect. In conclusion, the findings of the current study are promising.
Novelty and scientific contribution. This is the first study that aimed to evaluate the potential cytotoxic activity of two local Turkish plants, Smilax excelsa and Trachystemon orientalis, against C6 glioblastoma cells and the findings ensure that both plants may be used in the future as good therapeutic agents for treating cancer.