Mechergui, KaoutherCoelho, JoseSerra, Maria CelesteLamine, Sassia B.BOUKHCHINA, SADOKKhouja, Mohamed Larbi Arbi2011-11-302011-11-302010-08-15Mechergui K, Coelho J A, Serra M C, Lamine S B, Boukhchina S, Khouja M L.Essential oils of Origanum vulgare L. subsp glandulosum (Desf.) letswaart from Tunisia: chemical composition and antioxidant activity. Journal of the Science of Food and Agriculture. 2010; 90 (10): 1745-1749.0022-5142http://hdl.handle.net/10400.21/742BACKGROUND: Characterisation of the essential oils from O. glandulosum collected in three locations of Tunisia, chemical composition and the evaluation of their antioxidant activities were carried out. RESULTS: The essential oils from Origanum vulgare L. subsp. glandulosum (Desf.) letswaart collected from three localities of north Tunisia - Krib, Bargou and Nefza - were obtained in yields of 2.5, 3.0 and 4.6% (v/w), respectively. The essential oils were analysed by GC and GC/MS and assayed for their total phenolics content, by the Folin-Ciocalteu method, and antioxidant effectiveness, using the 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging assay. The main components of these essential oils, from Nefza, Bargou and Krib, were p-cymene (36%, 40% and 46%), thymol (32%, 39% and 18%), gamma-terpinene (24%, 12% and 16%) and carvacrol (2%, 2% and 15%), respectively). The ability to scavenge the DPPH radicals, expressed by IC50, ranged from 59 to 80 mg L-1. The total phenolic content, expressed in gallic acid equivalent (GAE) g kg(-1) dry weight, varied from 9.37 to 17.70 g kg(-1) dw. CONCLUSIONS: A correlation was identified between the total phenolic content of the essential oils and DPPH radical scavenger capacity. The occurrence of a p-cymene chemotype of O. glandulosum in the northern region of Tunisia is demonstrated.engOriganum glandulosumLamiaceaeEssential oilPhenolic compoundsAntioxidant activityP-cymene chemotypejournal article