Chemical composition, antioxidative and antimicrobial activity of allspice (Pimenta dioica (L.) Merr.) essential oil and extract

Abstract

Allspice (Pimenta dioica (L.) Merr.) fruit was used for the essential oil and ethanolic extract isolation in the present study. The essential oil was obtained by Clevenger-type hydrodistillation from allspice fructus with hydromodule 1:10 m/v during 180 minutes, while the ethanolic extract was obtained by reflux extraction at the boiling temperature with solvomodule 1:10 m/v during 120 minutes. The qualitative and quantitative composition of the essential oil was determined by GC/MS and GC/FID methods, respectively. The total phenolic and total flavonoid content in the extract was determined according to the Folin-Ciocalteu and aluminium chloride methods, respectively the antioxidant activity of allspice fructus essential oil and the extract was determined spectrophotometrically by DPPH assay and the antimicrobial activity using the microdilution method on the following microorganisms: two types of bacteria (Bacillus cereus, Salmonella spp.) and one yeast (Candida albicans), pairs of reference strains and their isolates. The obtained results proved the presence of 20 components in the essential oil, mainly oxygenated monoterpenes. The extract and essential oil have shown the best antioxidant activities after 20 and 60 minutes of incubation with EC50 values of 0.011 mg/cm³ and 0.023 mg/cm³, respectively. Both the essential oil and the extract have shown an inhibitory effect on all investigated microorganisms. Allspice ethanolic extract showed a better inhibitory effect on B. cereus and S. enterica (isolate and ATCC strains) than the essential oil. On the other side, allspice essential oil showed a better inhibitory effect on C. albicans strains. The results obtained indicate that both the essential oil and the extract isolated from allspice fructus are a good source of natural antioxidants and antimicrobial agents with potential applications in food and pharmaceutical industries as a safer alternative to the synthetic additives.