Annurca apple (Malus domestica cv. Annurca) is a traditional Southern Italian cultivar increasingly recognized as a polyphenol-rich food matrix with functional and nutraceutical relevance. Its distinctive post-harvest reddening process, together with tissue-specific differences among flesh, peel and core, influences its phytochemical profile, antioxidant capacity and biological activity. In addition, Annurca apple by-products, including peel and core fractions, are emerging as sustainable sources of food-derived bioactives. This review critically summarizes current evidence on An-nurca apple-derived polyphenols, bioactive fractions and by-products, focusing on their molecular mechanisms, context-dependent redox behavior and translational po-tential. Available studies indicate that Annurca-derived compounds and matrices should not be interpreted merely as antioxidant sources, but rather as modulators of redox-sensitive cellular pathways whose effects depend on fruit fraction, ripening stage, extract composition, dose, biological model and cellular context. In normal cel-lular models, Annurca-derived extracts and fractions have shown cytoprotective effects against oxidative damage, mercury-induced erythrocyte alterations, phosphatidylser-ine externalization, advanced glycation end product (AGE)-induced cytotoxicity and oxidative stress-induced senescence. These effects involve mechanisms related to ROS modulation, erythrocyte membrane homeostasis, calcium-dependent PLSCR1 regula-tion, antiglycative activity, endothelial protection and senescence-associated path-ways. Conversely, in cancer cell models, Annurca polyphenols may exert pro-oxidant and pro-apoptotic effects, mainly involving ROS/JNK signaling, inhibition of cell sur-vival, modulation of epithelial–mesenchymal plasticity and reduced migration. Addi-tional evidence on lipid metabolism, skin and hair biology, neuroprotective targets and by-product valorization supports broader functional and nutraceutical applications. However, most evidence remains preclinical and often relies on concentrated extracts or specific formulations. Future studies should address extract standardization, phy-tochemical fingerprinting, bioaccessibility, gut microbiota metabolism, circulating me-tabolites, dose relevance and clinical validation to clarify whether Annurca-derived bioactives can be developed as evidence-based functional ingredients or nutraceutical candidates.
Annurca Apple-Derived Polyphenols, Bioactive Fractions and By-Products as Context-Dependent Redox Modulators: Molecular Mechanisms and Nutraceutical Perspectives—A Narrative Review
Stefania D'Angelo
Writing – Review & Editing
2026-01-01
Abstract
Annurca apple (Malus domestica cv. Annurca) is a traditional Southern Italian cultivar increasingly recognized as a polyphenol-rich food matrix with functional and nutraceutical relevance. Its distinctive post-harvest reddening process, together with tissue-specific differences among flesh, peel and core, influences its phytochemical profile, antioxidant capacity and biological activity. In addition, Annurca apple by-products, including peel and core fractions, are emerging as sustainable sources of food-derived bioactives. This review critically summarizes current evidence on An-nurca apple-derived polyphenols, bioactive fractions and by-products, focusing on their molecular mechanisms, context-dependent redox behavior and translational po-tential. Available studies indicate that Annurca-derived compounds and matrices should not be interpreted merely as antioxidant sources, but rather as modulators of redox-sensitive cellular pathways whose effects depend on fruit fraction, ripening stage, extract composition, dose, biological model and cellular context. In normal cel-lular models, Annurca-derived extracts and fractions have shown cytoprotective effects against oxidative damage, mercury-induced erythrocyte alterations, phosphatidylser-ine externalization, advanced glycation end product (AGE)-induced cytotoxicity and oxidative stress-induced senescence. These effects involve mechanisms related to ROS modulation, erythrocyte membrane homeostasis, calcium-dependent PLSCR1 regula-tion, antiglycative activity, endothelial protection and senescence-associated path-ways. Conversely, in cancer cell models, Annurca polyphenols may exert pro-oxidant and pro-apoptotic effects, mainly involving ROS/JNK signaling, inhibition of cell sur-vival, modulation of epithelial–mesenchymal plasticity and reduced migration. Addi-tional evidence on lipid metabolism, skin and hair biology, neuroprotective targets and by-product valorization supports broader functional and nutraceutical applications. However, most evidence remains preclinical and often relies on concentrated extracts or specific formulations. Future studies should address extract standardization, phy-tochemical fingerprinting, bioaccessibility, gut microbiota metabolism, circulating me-tabolites, dose relevance and clinical validation to clarify whether Annurca-derived bioactives can be developed as evidence-based functional ingredients or nutraceutical candidates.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
