Polyphenolic profile and antioxidant activities of Madeiran elderberry (Sambucus lanceolata) as affected by simulated in vitro digestion

•The polyphenolic profile of Sambucus lancelolata was established for the first time.•The contents of polyphenols were significantly reduced upon the digestion process.•Anthocyanins were the most affected (87.2% reduction) by alkaline conditions.•The extracts of digested berries and leaves still had antioxidant activity.•Consumption of S. lanceolata berries and leaves may be health beneficial.

The aims of this study were twofold: a) to provide a detailed report on the phenolic composition and antioxidant activity of fresh berries and leaves of Sambucus lanceolata (Madeiran elderberry); b) to study the effects caused by a simulated in vitro digestion on the composition and antioxidant activity of the berries and leaves.Seventy-seven phytochemicals, mainly polyphenols, were identified in the methanol extracts of fresh berries and leaves, with the content of polyphenols higher in berries (27.2 mg·g− 1 dry extract, DE) than in leaves (25.9 mg·g− 1 DE). Anthocyanins were dominant in berries, while hydroxycinnamic acids (HCAs) and flavonols were abundant in leaves. Higher antioxidant activities were found in leaves than in berries, using several in vitro assays. After the simulated in vitro digestion, the levels of polyphenols were significantly reduced, in particular those of berries (81.8% decrease). Anthocyanins were the most affected compounds during the simulated digestion. However, despite the significant loss of phenolic compounds during digestion, methanol extracts of digested berries and leaves were still able to scavenge free-radicals. Hence, the consumption of leaves and/or berries of S. lanceolata may help prevent oxidative stress.