Characterization of “in vivo” sampled VOCs of Bixa orellana and its seeds extracts properties

The purpose of this study was to identify the volatile organic compounds (VOCs) profile of different organs of Bixa orellana plants sampled “in vivo” in the North of Pará State, Brazil. Sampling was done during an expedition on February 2011 within the Itaputyr project, an Italian-Brazilian experience of bottom-up cooperation for development. (1,2). Moreover, antioxidant capacity, phenolic content and insect repellent activity of powdered seeds extracts (aqueous and ethanolic) were tested. Branches, leaves, fruits and seeds were sampled "in vivo" using Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fibers with the HS-SPME technique. Each plant’s part was enclosed in a customised teflon cage (manufactured by SNK, Inc, Fullerton, CA: 11 x 21 cm) into which a manual SPME holder was inserted to extract the headspace. HS-SPME analyses were performed using a Trace GC Ultra Gas Chromatograph coupled to a quadrupole Mass Spectrometer Trace DSQ (Thermo-Fisher Scientific; Waltham, MA, USA). Volatile compounds detected in Bixa orellana seed headspace consisted mainly of sesquiterpenes, monoterpenes, and arenes. Most monoterpenes and sesquiterpenes have been previously detected in other spices and plants (3). α-humulene is the major volatile present in Bixa orellana seed extracts followed by D-germacrene, α-and β-pinene and γ-elemene. Some of the monoterpenes and sesquiterpenes found in plant extracts have been previously described as having antimicrobial and repellent properties (4). Phenolic content and antioxidat capacity, evaluated with Folin-Ciocalteur and DPPH tests respectively, were not so high, while preliminary data on repellency against Aedes aegypti of three different dried seeds extracts (ethanol, hexane, ethanol /water) indicated a significant activity