Chemical characterization, antioxidant, genotoxic and in vitro cytotoxic activity assessment of Juniperus communis var. saxatilis

Chemical composition and antioxidative, genotoxic and cytotoxic potential of essential oil (EO) and post-distillation waste (PDW) of Serbian Juniperus communis L. var. saxatilis Pall. was studied in human lung carcinoma (A549) and normal lung fibroblast (MRC-5) cells. GC-MS analysis identified 93.95% of total EO content and determined α-pinen as a dominant component (23.61%). LC-MS/MS analysis of PDW pointed at rutin (12.2 mg g−1) and quinic acid (11.1 mg g−1) as the most abundant. Antioxidativity of PDW was strong in DPPH (IC50 was 5.27 μg mL−1), and moderate in TBA and FRAP assays. Both substances were more cytotoxic to A549 than to MRC-5 cells. Obtained IC50 values were 69.4 μg mL−1 and 120 μg mL−1 for EO, and 1.27 mg mL−1 and 2.86 mg mL−1 for PDW, respectively. PDW was genotoxic (0.3 mg mL−1 and 1 mg mL−1 in A549 and MRC-5 cells, respectively) and induced apoptosis and arrested cell cycle in G2/M phase in A549 cells (0.3 mg mL−1). In mixtures with doxorubicin cytotoxicity of EO and PDW increased, and combination index values (0.12–0.18) revealed clear synergistic effect, stronger in cancer cells. This indicates that J. communis var. saxatilis could decrease the chemotherapeutic doses of doxorubicin, potentially reducing its side effects. https://ars.els-cdn.com/content/image/1-s2.0-S0278691517307925-fx1_lrg.jpg