Integrated evaluation of beneficial polyphenols and toxic alkaloids in edible flowers using miniaturized µSPEed extraction

Abstract

This work presents a miniaturized µSPEed-based sample preparation strategy for the simultaneous evaluation of selected polyphenols and toxic alkaloids of regulatory concern in fresh edible flowers. The approach combines solid–liquid extraction and µSPEed purification, using cartridges packed with 1.5 mg of octadecylsilane- functionalised mesoporous silica, for the analysis of: a) nine health-promoting polyphenols selected based on their widespread occurrence and reported relevance in edible flowers by UHPLC-PDA, and b) twenty-three pyrrolizidine and tropane alkaloids of toxicological and regulatory concern by UHPLC-MS/MS, while using minimal sample and solvent volumes in line with green analytical principles. Eleven edible flowers from eight species were analysed. Flowers of the toothache plant showed exceptionally high polyphenol content (147,830 ± 3015 µg/kg dry weight). On the other hand, alkaloid analysis revealed the presence of scopolamine in snapdragon. In borage flowers, intermedine N-oxide and lycopsamine N-oxide were found, with levels in one sample approaching regulatory limits. These findings highlight the importance of the targeted assessment of beneficial and potentially harmful phytochemicals in edible flowers to support consumer safety and risk assessment