Chemical constituents, antioxidant, antiproliferative and apoptotic effects of a new endemic Boraginaceae species: Paracaryum bingoelianum

In this study, the chemical profile, antioxidative, cytotoxic and apoptotic effects of essential oil of Paracaryum bingoelianum Behcet & Ilcim (Boraginaceae) were investigated in vitro. The chemical composition of P. bingoelianum essential oil (EO) was determined by HS-SPME/GC-MS method. DPPH free radical scavenging activity, ferric thiocyanate (FTC), and ferric reducing antioxidant potential (FRAP) methods were performed for revealing the antioxidant capacity of EO. The cytotoxic effect of EO was determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) cell viability assay on MCF-7 breast cancer and HT-29 colorectal adenocarcinoma cells. Apoptosis inducing effect of EO was evaluated by cell death detection Elisa (CDDE) assay and acridine orange/ethidium bromide staining method. Totally thirty-four compounds, representing 93.38% of the essential oil were identified. The DPPH scavenging activity of EO at 205 mu g/mL concentration, was found as close to vit. C. Besides, it was observed that EO had significant reducing power and total antioxidant capacity. The EO inhibited the proliferation of MCF-7 and HT-29 cells, and induced apoptosis. When compared with untreated cells, the viability of MCF-7 and HT-29 cells, which treated with 800 mu g/mL EO, decreased to 48.9% and 36.2%, respectively. In treated MCF-7 and HT-29 cells with EO at IC50 doses, the apoptosis was significantly induced, compared to untreated cells (pb0.0001). All these results suggest that P. bingoelianum contains important bioactive compounds, and might have antioxidant and antitumor activity. (C) 2020 Published by Elsevier B.V.