Polyphenol Composition, Antioxidant Properties, and Health Benefits of Moroccan-Cultivated Raspberries, Blackberries,...

Despite Morocco's emergence as the world's fourth-largest berry exporter, no comprehensive review has evaluated the polyphenol composition, antioxidant properties, and health benefits of raspberries (Rubus idaeus), blackberries (Rubus fruticosus), and blueberries (Vaccinium corymbosum) specifically within the Moroccan cultivation context. This narrative review synthesized evidence from phytochemical analyses, in vitro and in vivo studies, randomized controlled trials (RCTs), meta-analyses, and epidemiological data sourced from PubMed, Scopus, and Web of Science. Blackberries exhibited the highest total polyphenol content (149 μmol GAE/L) and antioxidant capacity, driven primarily by anthocyanin concentration and diversity. Antioxidant mechanisms included free radical scavenging, transition metal chelation, and upregulation of endogenous antioxidant enzymes. Pooled RCT data demonstrated that regular consumption (150-300 g/day) significantly reduced systolic blood pressure (-2.72 mmHg), LDL cholesterol (-0.21 mmol/L), and fasting glucose (-2.70 mg/dL). Additional benefits included neuroprotection via blood-brain barrier crossing and brain-derived neurotrophic factor (BDNF) elevation, prebiotic modulation of Bifidobacterium, Lactobacillus, and Akkermansia populations, and anti-cancer activity via nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) inhibition. Processing significantly affected bioactive retention: freezing preserved phenolic compounds effectively, while conventional drying reduced anthocyanin content by up to 49%. These findings support the integration of Moroccan-cultivated berries-particularly from the Gharb, Loukkos, and Souss-Massa regions-into evidence-based dietary and functional food strategies. Priority research gaps include bioavailability assessment, dose-response characterization, and cultivar-specific phytochemical profiling under Moroccan agro-climatic conditions.