In this study; it was aimed to investigate the anticancer and cytotoxic activities on DU-145 prostate cancer and MCF-7 breast cancer cell lines and WI-38 human fibroblast cell line of essential oil (Nioli) obtained from Melaleuca viridiflora Sol. ex Gaertn. plant and its antimicrobial effects on various bacteria and yeast cells. Content analyzes of Nioli essential oil were made by Gas Chromatography-Mass Spectrometry (GK-KS). The antimicrobial effects of the essential oil were determined using Disk Diffusion and Minimum Inhibition Concentration (MIC) tests. Its cytotoxic effects were determined by the XTT (2,3-bis-(2-methoxy-4-) nitro-5)-sulfophenyl)-2H-tetrazolium-5-carboxanilide) test; were investigated at different concentrations in breast cancer (MCF-7), prostate cancer (DU-145) and healthy human fibroblast (WI-38) cell lines. In the disc diffusion method of essential oil; It was determined that it formed an inhibition zone against Klebsiella pneumoniae bacteria at 200, 100, 50, 25 and 12.5 µg/mL concentrations, and against Candida albicans yeast at 200 and 100 µg/mL concentrations. Nioli essential oil showed the highest antibacterial effect against Bacillus cereus. While it was moderately effective against Pseudomonas aeruginosa and Candida albicans, it reached MIC values effective against other bacteria. It was observed that the anticancer activity of Nioli essential oil was more effective in DU-145 prostate cancer cells compared to MCF-7 breast cancer cells, and it had no toxicity in WI-38 healthy human fibroblast cells.

The aim of the study is to evaluate the ethanol extract of Rheum ribes root (RTE), as well as the root and young shoots (RYSE), for its chemical composition, antioxidant properties and cytotoxic effects. Total polyphenols (TPC), total flavonoid (TFC), radical scavenging activity (DPPH), the ferric reducing antioxidant power (FRAP) of Rheum ribes extracts were determined using colorimetric methods. Mineral contents and vitamin values of samples were determined by ICP-MS and HPLC, respectively. The cytotoxic effect of Rheum ribes extracts was determined on different cells using XTT assay. The cytotoxic effects of RTE and RYSE on cancer cells were evaluated with regard to apoptosis. According to results, mineral contents, vitamine A and C values were very high in both samples. Ethanolic extracts of Rheum ribes young shoot exhibited a selective cytotoxic effect on all cancer cells compared to WI-38 cells, and the IC50 values of the extract in the cancer cells between 26.10 to 54.81 μg/mL. Ethanolic extracts of RTE and RYSE induced apoptosis on MCF-7 cells. The ethanolic extracts of Rheum ribes has effective cytotoxic and antioxidant activity. More research is needed to determine the cytotoxic effect mechanisms on cancer cells.