The Metabolomic Profile of the Essential Oil from Zanthoxylum caribaeum (syn. chiloperone) Growing in Guadeloupe FWI using GC × GC-TOFMS.

The essential oil (EO) from the leaves of Zanthoxylum caribaeum (syn. Chiloperone) (Rutaceae) was studied previously for its acaricidal, antimicrobial, antioxidant, and insecticidal properties. In prior studies, the most abundant compound class found in leaf oils from Brazil, Costa Rica, and Paraguay was terpenoids. Herein, essential oil from the leaves of Zanthoxylum caribaeum (prickly yellow, bois chandelle blanc (FWI), peñas Blancas (Costa Rica), and tembetary hu (Paraguay)) growing in Guadeloupe was analyzed with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOFMS), and thirty molecules were identified. A comparison with previously published leaf EO compositions of the same species growing in Brazil, Costa Rica, and Paraguay revealed a number of molecules in common such as ß-myrcene, limonene, ß-caryophyllene, α-humulene, and spathulenol. Some molecules identified in Zanthoxylum caribaeum from Guadeloupe showed some antimetabolic effects on enzymes; the in-depth study of this plant and its essential oil with regard to metabolic diseases merits further exploration.

Revisiting the Vibrational and Optical Properties of P3HT: A Combined Experimental and Theoretical Study.

We demonstrate that DFT-based calculations can provide straightforward means to analyze the effect of aggregation on the optical properties of regioregular P3HT oligomers of different lengths (up to 20-mers) and of bioligomers of 8-mers in two different conformations. Our conclusions substantially differ from those obtained previously by applying the exciton model. Indeed, analysis of Huang-Rhys factors has evidenced that two vibrational modes, a collective mode and an effective mode, are combined in the vibronic structure of the absorption spectrum of oligothiophene. Computed spectra match perfectly their experimental counterparts provided we consider that the oligomer and at least the five lowest excited states of bioligomers behave as absorbers, and that both oligomer and bioligomer contribute to the emission spectra. Study of the nature of the Franck-Condon excitation and optimization of the five lowest excited singlet states indicate that high (hot) excited states of the bioligomer may play an important role in the initiation of charge separation and highlight the importance to take into account the relaxation processes in the theoretical modeling of emission properties.