Taxonomy-Dependent Seed Tocochromanol Composition in the Rutaceae Family: Application of Sustainable Approach for Their Extraction.

Several members of the Rutaceae (citrus) family are widely cultivated and processed. Tocopherol (T) synthesis and composition are well-documented, while tocotrienols (T3) in most plant families remain underreported. To amend this, mass screening of Rutaceae species' seed tocochromanols were analysed. Of the 53 analysed species, seed tocochromanols were tocotrienol-dominated in 22 species, including a majority of species Zanthoxyloideae (Choisya, Dictamnus, Melicope, Ptelea, Skimmia, Tetradium, Zanthoxylum) and the Cneoroideae (Cneorum) subfamily. Total tocochromanol content ranged from 0.20-25.98 mg 100 g-1 dry weight (dw) seeds. The highest tocochromanol content was observed in Murraya paniculata, Ruta graveolens seeds, the highest tocotrienol (T3) content was observed in Skimmia anquetilia and Dictamnus albus-19.80 and 19.70 mg 100 g-1 dw, respectively. The major tocochromanols in the seeds were γ-T and γ-T3, while others were present in low concentration or absent. Linear discriminant analysis (LDA), principal component analysis (PCA) and non-hierarchal cluster analysis (N-HCA) identified similar tocochromanol content trends in the Rutoideae subfamily species and the Bergera and Murraya genus, while the Zanthoxyloideae subfamily species' seed tocochromanol composition was highly variable. The efficient extractability of tocochromanols using sustainable solvent-ethanol is demonstrating suitability of this approach for daily samples screening and bioactive extraction.