Chemical Characterization of Five TunisianEucalyptusEssential Oils Species

Abstract

Hydrodistillation of the dried leaves of five Eucalyptus species, E. alba REINW. ex BLUME, E. citriodora HOOK., E. paniculata SM., harvested from Choucha arboreta (region of Sejnane, northwest of Tunisia), E. pimpiniana MAIDEN from Mjez Elbab arboreta (north east of Tunisia) and E. bicolor A.CUNN ex HOOK from Sidi Smail arboreta (center of Tunisia), in March 2017, afforded essential oils in yields varying from 1.3 � 0.2 to 6.0 � 0.9 % according to the species. E. citriodora provided the highest mean percentage of essential oil amongst all the species. Analysis by GC (RI) and GC/MS allowed the identification of 138 components representing 84.6 -98.7 % of the total oil. The content of the different samples varied according to the species. The main components were citronellol, followed by 1, 8-cineole, α-pinene, τ-cadinol, 7-epi-α-eudesmol, trans-pinocarveol, spathulenol, aromadendrene, γ-cadinene and δ-cadinene. The principal components and the hierarchical cluster analyses separated the five leaf essential oils into three groups, each group constituted a chemotype.

Essential Oil Composition, Antioxidant Activity and Leaf Micromorphology of Five Tunisian Eucalyptus Species

“…Some studies have reported the composition of the EO of E. alba , even though only one reported that from plants grown in Tunisia. Elaissi and coworkers [ 51 ] reported an EO rich in eucalyptol (44.1%) and appreciable amounts of sesquiterpenes, such as spathulenol (5.8%), globulol (4.9%), and trans -caryophyllene; this composition agrees in part with data recorded in the present study. Our composition generally is consistent with the chemical profiles of the EO of E. alba grown in other countries: Bangladesh [ 52 ], Congo [ 53 ], Senegal [ 54 , 55 ], and Burkina Faso [ 56 ].…”

Antimicrobial, Herbicidal and pesticidal potential of Tunisian eucalyptus species: Chemoprofiling and biological evaluation

“…The examination of E. bicolor EO by Elaissi and coworkers [ 29 ] highlighted similarities in composition with our study, presenting shared compounds such as eucalyptol, aromadendrene, α-pinene, and trans -pinocarveol. While the quantities differed, the commonality in major components highlights consistency in the chemical composition.…”

“…For instance, the EO from E. bicolor demonstrated similarity to EO yields from Iraq (1.45 %) as reported by Dehghani et al (2023) [ 28 ]. A separate study conducted in Tunisia indicated 1.50 ± 0.3 % EO yield [ 29 ], while another study from the Province of Isfahan, Iran reported 1.85 % EO yield [ 30 ]. However, for species such as E. amplifolia , E. salubris , and E. campaspe , the yields observed in this study surpass previously documented values.…”

Chemistry and Bioactivities of Six Tunisian Eucalyptus Species

“…However, the same authors [ 32 ] reported the composition of an E. paniculata EO with higher amounts (89.8%) of oxygenated components, first of all sesquiterpenes alcohols (τ-cadinol and 7-epi-α-eudesmol), sesquiterpenes oxides (caryophyllene oxide) and monoterpene oxides (eucalyptol). Dorsaf and coworkers [ 3 ] inferred the chemical characterization of a Tunisian EO from E. transcontinentalis ; also in this case, the results displayed eucalyptol as the main component followed by α-pinene.…”