Total phenols, flavonoids, flavonols, and flavanols of the methanolic extract of the aerial part of Artemisia herba-alba were determined. The extract was analyzed by liquid chromatography with photodiode array coupled with electrospray ionisation mass spectrometry and allowed to identify of 10 phenolic compounds. Apigenin-6-C-glycosyl flavonoids and caffeoylquinic acids were identified. Chlorogenic acid and 1,4 dicaffeoylquinic acid being the major constituents. The essential oil obtained by hydrodistillation was analyzed by gas chromatography–mass spectrometry. Twenty-three compounds, representing 97.8% of the total oil, were identified. The most abundant components were β-thujone (41.9%), α-thujone (18.4%), and camphor (13.2%). Methanolic extract and essential oil exhibited a considerable antioxidant activity as evaluated by 2,2-diphenyl-pycrilhydrazil hydrate scavenging activity, reducing power, β-carotene bleaching test, and chelating ability. The methanolic extract was found to be more efficient, while the essential oil exhibited the highest acetylcholinesterase inhibitory activity. Analysis of the antibacterial activity showed that A. herba-alba methanolic extract and essential oil are efficient against gram positive and gram negative bacteria.
1 August 2011 in Biochemical Systematics and Ecology
Hertia cheirifolia is an endemic medicinal species of the Tunisian and Algerian flora. The species was found to be rich in monoterpene hydrocarbons and sesquiterpene lactones. Significant variation of essential oil composition was observed between the plant organs. Flower buds were characterized by the highest content of the drimane type (34.08%). Leaf essential oil showed the uppermost percentage of α-pinene (35.63%). Flowers and flower buds exhibited the highest amount of germacrene D (13.18 and 12.80%, respectively). The composition of leaf essential oil varied significantly depending on the harvesting time. The lowest amount of α-pinene (19.49%) and the uppermost contents of drimenin (36.16%) and the drimane type (29.14%) were observed in January (the beginning of the fruiting stage), while leaves collected in March (the full fruiting stage of plants) were marked by the most important accumulation of germacrene D (21.18%). All essential oils were found to possess antioxidant, acetylcholinesterase (AChE), and α-amylase inhibitory activities. The level of activity varied according to the oil composition. Leaf essential oils collected at the full flowering stage exhibited the important radical scavenging capacity (22.3 mg Eq trolox/g EO) and the uppermost inhibitory activities against AChE (2.91 mg Eq donepezil/g EO) and α-amylase (14.4 mg Eq acarbose/g EO). Flower buds essential oils were the most efficient inhibitors of AChE (1.86 mg Eq donepezil/g EO), while essential oils of leaves and fruits possess the highest activity against α-amylase (8.32 and 8.84 mg Eq acarbose/g EO, respectively).
1 November 2020 in Journal of Essential Oil Bearing Plants
The essential oils extracted from different organs of Pinus halepensis were analyzed by GC-FID and GC-MS and evaluated for their antioxidant and anti-acetylcholinesterase and anti-butyrylcholinesterase activities. The composition and biological activities of essential oils extracted from immature cones, juvenile needles and male inflorescences were analyzed for the first time. The common compounds of the investigated essential oils were α-pinene (6.4 to 46.1 %), β-myrcene (5.5 to 28.3 %), β-caryophyllene (1.3 to 32.8 %), β-caryophyllene oxide (2.7 to 66.6 %) and α-humulene (2.4 to 5.8 %). Significant variations of essential oil composition were detected between the investigated plant parts. The analyzed essential oils exhibited antioxidant and anticholinesterase activities. These activities varied significantly among organs. The essential oil of needles showed the highest antiradical activity with DPPH assay (0.31 mg eq Trolox/g EO). However, for ABTS radical scavenging assay, juvenile needles showed the uppermost antioxidant activity (2.52 mg eq Trolox/g EO). Male inflorescences possessed the most important chelating activity (267.43 mg eq EDTA/g EO). Essential oils of juvenile needles exhibited the highest antiacetylcholinesterase activity (1.37 mg eq dopenzil/g EO). Male inflorescences revealed the most important activity against butyrylcholinesterase (57.442 mg eq dopenzil/g EO).