Tocotrienol-Dominated Berberidaceae Species' Seed Tocochromanols: Screening via Ultrasound-Assisted Extraction in Ethanol.

Inspired by the lack of wide-scale family level screenings, the profile of tocochromanols in Berberidaceae family species belonging to the Berberis, Mahonia, Caulophyllum, Jeffersonia and Podophyllum genera was studied. Seeds were acquired from botanical gardens around the world and tocopherol and tocotrienol content was tested using ultrasound-assisted extraction in ethanol (UAEE) and compared to saponification protocol and analyzed by an RP-HPLC-FLD system. The UAEE protocol produced 93% average tocochromanol recovery compared to the saponification protocol. All investigated samples were tocotrienol-dominated, the lowest proportions being in B. regeliana, B. thunbergii and B. aristata at means of 55%, 56% and 58%, respectively. The main tocochromanol constituents were α-tocotrienol and γ-tocotrienol. The highest α-tocotrienol content was observed in B. tchonskyana at 9.14 mg 100 g-1 dw, and the highest γ-tocotrienol and sum of free tocochromanol content was observed in J. diphylla at 18.00 and 23.76 mg 100 g-1 dw, respectively. Principal component analysis and k-means cluster analysis based on a free tocochromanol profile indicated γ-tocotrienol and α-tocotrienol content as the main differentiators. However, a comprehensive sample set could only be collected for the Berberis genus, warranting further research into Berberidaceae seed tocochromanols.