Chemical Composition, Antioxidant and Antimicrobial Properties of Essential Oil and Extracts from Heracleum sphondylium L.

Abstract

The present study describes chemical composition of essential oil, total phenolic and flavonoid content and in vitro antioxidant and antimicrobial activity of essential oil and various extracts from Heracleum sphondylium L. (Apiaceae). The essential oil isolated by hydrodistillation from the aerial parts was analyzed using combined GC and GC-MS. The dominant constituents in the oil were ar-curcumene (13.42%), β-sesquiphellandrene (11.91%) and β-bisabolene (10.11%). The total phenolic content in the extracts was determined using Folin-Ciocalteu reagent and their amounts ranged between 38.04 to 110.15 mg GA (gallic acid)/g. The concentrations of flavonoids in the extracts varied from 27.57 to 82.54 mg Qu (quercetin)/g. Antioxidant activity was analyzed using DPPH reagent. Antioxidant activity ranged from 2.50 to 24.16 IC 50 (mg/ml) and from 1.16 to 3.13 mg VitC (vitamin C)/g when tested with the DPPH and ABTS reagents, respectively. The antimicrobial activity of the essential oil and extracts was investigated using a micro-well dilution assay for the most common human gastrointestinal pathogenic microbial strains: Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus and yeast Candida albicans. The results showed that minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations of essential oil and extracts ranged from 1.56 mg/ml (for the most sensitive B. cereus) to above 50 mg/ml for S. enteritidis and E. coli. This finding suggests that H. sphondylium L. may be considered as a natural source of antioxidants and antimicrobial agents.