Chemical composition, biological and pharmaceutical potential of essential oils from native medicinal plants

Abstract

This project was designed to evaluate the chemical composition, antioxidant, antimicrobial, anti-inflammatory and anticancer activities of the essential oils of nine plants. The essential oils were isolated through steam distillation and characterized by GC and GC-MS techniques. Different antioxidant assays were used to examine the antioxidant potential of essential oils. The highest activity was observed against Lantana camara essential oil with IC50 5.45 μg mL-1 in DPPH assay and 78.95% inhibition in case of β-carotein linoleic acid assay. Antimicrobial potential was determined by disc diffusion assay and Minimum inhibitory concentration (MIC). All essential oils possessed good antimicrobial potential while among all tested oils Cymbopogon flexuosus essential oil showed the highest activity (27.9 and 32.5 mm) against Staphylococcus aureus and Helmenthosporium solani in case of bacterial and fungal strains respectively. The anticancer potential was checked by different assays, Lantana camara, Pinus roxburghii, Cymbopogon flexuosus and Citrus pseudolimon essential oils showed excellent cytotoxic potential against HCT-116 (colon cancer), KBM-5 (myelogenous leukemia), U-266 (multiple myeloma cells), MiaPaCa-2 (pancreatic cancer cells), A-549 (lung carcinoma cells) and SCC-4 (squamous cell carcinoma) human cancer cell lines. In addition, they induced the inhibition on nuclear factor κB (NF-κB) in a dose-dependent manner. Flow cytometric analysis indicated that treatment with essential oils resulted in Go/ G1 cell cycle arrest in a dose-dependent manner. GC-MS analysis revealed that α-Pinene (27.11%) in Pinus roxburghii,, Caryophyllene oxide (19.63) in Lantana camara , trans-citral (21.65%) in Cymbopogon flexuosus while limonene (58.01%) in Citrus pseudolimon were the major components. Presented results suggest that selected essential oils are good sources of phytochemicals with antioxidant and antimicrobial activities and can play an important role in cancer prevention.