Chemical profile, enzyme inhibitory and antioxidant activities of essential oils of an endemic Algerian species: Abies numidica. De Lannoy ex Carrière

ABSTRACT

The essential oils (EOs) from needles, twigs and cones of Abies numidica, an endemic tree from Algeria, were analysed by gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and 13C nuclear magnetic resonance (¹³C NMR). Fifty, forty-nine, and thirty-eight components from needles, twigs and cones were identified accounting for 86.0%, 93.5% and 93.8% of the total EO, respectively. EOs were mainly composed of monoterpene hydrocarbons (46.3%-86.0%), followed by sesquiterpene hydrocarbons (2.6%-33.6-%). The antioxidant activity was determined using five tests: ABTS, β-Carotene bleaching, DPPH, FRAP and phosphomolybdenum. Cholinesterase inhibition potential of EOs was also evaluated. EO of cones was found to have the highest antioxidant activity for most of the tests performed. All EOs exhibited better antiacetylcholinesterase (AChE) than antibutyrylcholinesterase (BChE) activities at various rates. The most potent AChE inhibition was observed for twigs EO (IC₅₀ = 2.73 g/mL), followed by needles (IC₅₀ = 4.09 µg/mL) while cones’ EO showed least potential (IC₅₀ = 13.64 µg/mL).

KEYWORDS:

• Abies numidica
• chemical composition
• antioxidants
• acetylcholinesterase
• butyrylcholinesterase

Disclosure statement

No potential conflict of interest was reported by the author(s).

In honour of Professor Robert Adams

Robert Adams was a well accomplished scientist. He may be gone but he will not be forgotten by any of us that he touched in some way or another. I have benefited from his guidance for my research. As recognition, this work will be dedicated to his memory. Rest in peace Robert.