The expanding olive oil industry in Brazil generates a substantial amount of by-products, such as olive leaves, which are sources of bioactive compounds, particularly phenolics, and can be consumed as infusions. While the anticancer properties of olive phenolics are well documented, little is known about their bioaccessibility after gastrointestinal digestion, which may influence their bioavailability and bioactivity, including antitumor effects. Growing cancer incidence underscores the need for strategies based on naturally derived bioactive compounds. This study evaluated the phenolic profile, antioxidant capacity, and antitumor potential of Brazilian olive leaf infusions (OLIs) from Picual and Coratina cultivars before and after simulated gastrointestinal digestion (INFOGEST 2.0). OLIs and their in vitro digestion fractions were evaluated for antioxidant activity (DPPH and ABTS) and for phenolic content and profile (Folin–Ciocalteu and UHPLC-ESI-MS/MS in full scan mode). Antitumor assays in HCT116, HT29, and HepG2 cell lines assessed cell viability, ROS production, apoptosis/necrosis, and clonogenic survival. Both cultivars produced phenolic-rich OLIs, mainly composed of oleoside-type secoiridoids. Simulated digestion modified phenolic composition and enhanced antioxidant capacity. The intestinal fraction exhibited ~40% bioaccessibility, mainly composed of secoiridoids. Treatments with OLIs and their bioaccessible fractions decreased HCT116, HT29, and HepG2 cells’ viability (IC50 ~400–1400 μg/mL/24 h), reduced clonogenic potential (~50%), increased intracellular ROS (1.2–2.7-fold), and induced cell death (20–50%). These findings highlight the potential of Brazilian olive leaf infusions as a promising dietary source of bioaccessible BCs with antitumor properties.
Phenolic profile, bioaccessibility, and bioactivity of Brazilian olive leaf infusions (Olea europaea L.) after simulated gastrointestinal digestion
Difonzo, Graziana;Pasqualone, Antonella;Caponio, Francesco;Zago, Lilia
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2026-01-01
Abstract
The expanding olive oil industry in Brazil generates a substantial amount of by-products, such as olive leaves, which are sources of bioactive compounds, particularly phenolics, and can be consumed as infusions. While the anticancer properties of olive phenolics are well documented, little is known about their bioaccessibility after gastrointestinal digestion, which may influence their bioavailability and bioactivity, including antitumor effects. Growing cancer incidence underscores the need for strategies based on naturally derived bioactive compounds. This study evaluated the phenolic profile, antioxidant capacity, and antitumor potential of Brazilian olive leaf infusions (OLIs) from Picual and Coratina cultivars before and after simulated gastrointestinal digestion (INFOGEST 2.0). OLIs and their in vitro digestion fractions were evaluated for antioxidant activity (DPPH and ABTS) and for phenolic content and profile (Folin–Ciocalteu and UHPLC-ESI-MS/MS in full scan mode). Antitumor assays in HCT116, HT29, and HepG2 cell lines assessed cell viability, ROS production, apoptosis/necrosis, and clonogenic survival. Both cultivars produced phenolic-rich OLIs, mainly composed of oleoside-type secoiridoids. Simulated digestion modified phenolic composition and enhanced antioxidant capacity. The intestinal fraction exhibited ~40% bioaccessibility, mainly composed of secoiridoids. Treatments with OLIs and their bioaccessible fractions decreased HCT116, HT29, and HepG2 cells’ viability (IC50 ~400–1400 μg/mL/24 h), reduced clonogenic potential (~50%), increased intracellular ROS (1.2–2.7-fold), and induced cell death (20–50%). These findings highlight the potential of Brazilian olive leaf infusions as a promising dietary source of bioaccessible BCs with antitumor properties.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
