*2.5. Characterization of Polyphenolic Compounds by UPLC-PDA System*

The preparation of the PEP extracts subjected to characterization of polyphenolic compounds using the UPLC-PDA system was performed according to Wojdyło et al. [21]. All determinations were done in duplicate. The results were expressed as grams per 100 g of dry basis (db) of plum extract power (g/100 g db).
