Marzie Kamali - Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran
Jafar Valizadeh - Department of Biology, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran
Hamid Reza Shaterian - Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran
Javad Mottaghipisheh - Center for Molecular Biosciences (CMBI), Institute of Pharmacy/Pharmacognosy, University of Innsbruck, Innrain ۸۰-۸۲, ۶۰۲۰ Innsbruck, Austria

Melia azedarach L. (Meliaceae family) is traditionally consumed to treat rheumatic pains, astringent, skin diseases, and diuretics. The present study aims to investigate the chemical composition of the flowers essential oil, as well as in vitro antioxidant activities of the leaves and fruits extracts of M. azedarach by DPPH (۲,۲-diphenyl-۱-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays. The GC-MS analysis of the essential oil identified oxygenated sesquiterpenes (۴۳.۷%) as the major chemical class. The volatile oil was rich in trans-nerolidol (۳۹.۵%), ۱,۴-dimethoxybenzene (۱۱.۶%), ۲-phenylacetaldehyde (۹.۱%), and phenyl ethyl alcohol (۷%). The leaves ethanolic extracts (LEE) indicating the IC۵۰ values ۱۴۹ ± ۰.۰۵ µg/mL and ۲۰.۳۱ ± ۰.۰۳ mmol of the FeSO۴/g of the extract exhibited the strongest radical scavenging activity assessed via DPPH and FRAP assays, respectively. The higher antioxidant activity of LEE was correlated with the higher total phenolic contents (۴۲.۸۶ ± ۰.۰۲ μg gallic acid/mg extract) compared to the fruits (۲۶.۸ ± ۰.۰۵ μg gallic acid/mg extract). To the best of our knowledge, this is the first report on the essential oil compositions and the antioxidant activity of this species collected from the southeast ofIran. This study highlights that the M. azedarach essential oil can be a rich natural source of trans-nerolidol with diverse biological activities. Additionally, the ethanolic extract of leaves has significant antioxidant activities. Therefore, these findings might direct further complementary phytochemical and biological investigations of this species.

Antioxidant activity, essential oil, Melia azedarach, Trans-nerolidol, Phytochemical profile