Industrial Crops and Products 76 (2015) 121–127 Contents lists available at ScienceDirect Industrial Crops and Products journal homepage: www.elsevier.com/locate/indcrop Chemical composition, fumigant and anti-acetylcholinesterase activity of the Tunisian Citrus aurantium L. essential oils Khaoula Zarrad a,b,d,∗ , Amel Ben Hamouda b , Ikbal Chaieb b,c , Asma Laarif b , Jouda Mediouni-Ben Jemâa d a Institut Supérieur Agronomique de Chott Mariem (ISA), Université de Sousse, Tunisia b UR13AGR09, Centre Régional des Recherches en Horticulture et Agriculture Biologique (CRRHAB), Université de Sousse, Tunisia c Laboratoire de Protection des Végétaux, Institut National de la Recherche Agronomique de Tunisie (INRAT), Université de Carthage, Tunisia d Laboratoire de Biotechnologie Appliquée à l’Agriculture, Institut National de la Recherche Agronomique de Tunisie (INRAT), Tunisia a r t i c l e i n f o Article history: Received 19 January 2015 Received in revised form 11 June 2015 Accepted 15 June 2015 Keywords: Citrus aurantium Essential oil Limonene Bemisia tabaci Non-competitive inhibition IPM a b s t r a c t The present work reported first investigations on fumigant and anti-cholinesterase activities of C. auran- tium essential oils and pure limonene towards Tunisian strain of Bemisia tabaci. GC and GC–MS analysis showed a high percent of limonene (87.523%). C. aurantium oils and the single compound were known to be potent AChE inhibitor with IC 50 value of 2.94 mM and 3.54 mM, respectively. Furthermore, it was observed that the oil and its major compound showed a reversible non-competitive inhibition revealed that these components might bind both the enzyme alone and the enzyme–substrate. Significant pest fumigant activity was demonstrated. Fumigant treatments have shown that B. tabaci mortality rate increased with the increase in essential oils concentration. Complete insect mortality was detected at the highest concentration (20 L/L air) within 24 h of exposure, whereas, at the least concentration (2.5 L/L air) mortality varied from 41 to 47.67% for the single compound and the oil, respectively. These results suggest that oils from C. aurantium peels may be promising as models to develop new insecticides that might be applied into the integrated management of whiteflies. © 2015 Elsevier B.V. All rights reserved. 1. Introduction In recent years, essential oils and separated components are attracting particular interest and are extensively used in medicine, cosmetics and pharmaceutical industry (Bakkali et al., 2008). Among the great variety of essential oils, Citrus fruit essential oils and their major components are extensively used as flavoring agents in a number of food, beverage, and confectionery products and fragrance application (Fisher and Phillips, 2008; Steuer et al., 2001). Newly, other applications make use of the chief compound of the oil extracted from Citrus peels, limonene, as green solvent for Soxhlet extraction (Virot et al., 2008) due to its ability to solubi- lize fats (Mamidipally and Liu, 2004). In particular, better orange essences are exploited in food and cosmetic industries, mostly owing to their richness in flavonoids, coumarins, triterpenes and vitamin (Haggag et al., 1999). Moreover, they also possess antiox- ∗ Corresponding author at: Institut Supérieur Agronomique de chott Mariem (ISA), Université de Sousse, Tunisia and Laboratory of Biotechnology Applied to Agricul- ture, INRAT, Ariana, Tunisia. E-mail address: zarredkhaoula@yahoo.com (K. Zarrad). idant (Moulehi et al., 2012), antibacterial (Friedman et al., 2002), fungicidal (Ramadan et al., 1996) and insecticidal activities (Laarif et al., 2013). The silverleaf whitefly Bemisia tabaci Genn. (Hempitera: Aleyro- didae) is a polyphagous insect pest of economic important causing significant crop losses throughout the world and in Tunisia (Parrella et al., 2012; Laarif et al., 2015). It is a devastating global pest that feeds on vegetables, cotton and several economically important crops (Dinsdale et al., 2010). This cosmopolitan insect pest feed on phloem, excrete honeydew on the leaves and fruit (Horowitz et al., 2005) and transmits several plant viruses (Alves et al., 2008; Baldin and Beneduzzi, 2010). Chemical insecticides are currently used for controlling B. tabaci, resulting in environmental pollution and resis- tance in pest population. Indeed, B. tabaci has been recognized as resistant to various systematic insecticides like organophosphates, carbamates, cyclodienes, synthetic pyrethroids and neonicotinoids (Dennehy et al., 2010; Vassiliou et al., 2011; Yuan et al., 2012). Citrus essential oils were recommended by several researches as alternatives to chemical insecticides for the control of a wide range of pests. In this context, toxic effects of Citrus aurantium L. and Cit- rus limon L. essential oils have been reported toward Spodoptera frugiperda J.E. Smith larvae (Villafane et al., 2011). Additionally, the http://dx.doi.org/10.1016/j.indcrop.2015.06.039 0926-6690/© 2015 Elsevier B.V. All rights reserved.