Chemical composition and acetylcholinesterase inhibitory activity of Artemisia maderaspatana essential oil

Context: To date, there are no reports to validate the Indian traditional and folklore claims of Artemisia maderaspatana L. (syn. Grangea maderaspatana L.) (Asteraceae) for the treatment of Alzheimer's disease. Objective: The present study characterizes the volatile components (non-polar compounds) of A. maderaspatana and evaluates its acetylcholinesterase inhibition potential. Materials and methods: The essential oils (yield 0.06% v/w) were obtained from fresh aerial part of A. maderaspatana. The characterization of volatile components (non-polar compounds) was performed by GC-MS data and with those of reference compounds compiled in the spectral library of in-house database. The in vitro acetylcholinesterase (AChE) inhibition of the volatile organic constituents (VOC's) of A. maderaspatana aerial part was evaluated in varying concentration ranges (0.70-44.75 mu g/mL) with Ellman's method. Results: The major components were a-humulene (46.3%), beta-caryophyllene (9.3%), alpha-copaene (8.2%), beta-myrcene (4.3%), Z(E)-alpha-farnesene (3.7%), and calarene (3.5%). Chemical variability among other Artemisia spp. from different climatic regions of India and countries namely Iran and France was observed. The experimental results showed that diverse volatile organic constituents of A. maderaspatana have significant acetylcholinesterase inhibitory activity (an IC50 value of 31.33 +/- 1.03 mu g/mL). This is the first report on the inhibition of acetylcholinesterase properties of essential oil of A. maderaspatana obtained from fresh aerial part. Conclusions: The present results indicate that essential oil of A. maderaspatana isolated from the northern region of India could inhibit AChE moderately. Therefore, the possibility of novel AChE inhibitors might exist in VOCs of this plant.