Neuroprotective effect of blackberry (Rubus sp.) polyphenols is potentiated after simulated gastrointestinal digestion

► We evaluated undigested and in vitro digested blackberry metabolites. ► Blackberry digested in vitro showed different phenolic composition. ► Physiological concentrations of undigested metabolites did not protect neurons. ► Digested metabolites protected neuroblastoma from death contrary to undigested ones. ► Mechanisms beyond cellular antioxidant systems are involved.