The pharmacological and therapeutic versatility of Allium species: a comprehensive exploration of bioactive constituents and biological activities

The Allium genus, encompassing garlic, onion, chives, and related species, has been an integral part of traditional medicine for centuries due to its remarkable pharmacological properties. This review consolidates current insights into the therapeutic potential of Allium species, focusing on their diverse bioactive compounds, including organosulfur compounds, flavonoids, phenolics, phytosterols, and essential oils. These constituents confer a wide range of biological activities, including anti-inflammatory, antioxidant, antimicrobial, anticancer, antiviral, antidiabetic, and hepatoprotective effects. Key bioactive such as allicin, ajoene, and S-allyl cysteine play pivotal roles in modulating cellular signaling pathways like Nuclear Factor kappa B (NF-κB), Mitogen-Activated Protein Kinase (MAPK), Phosphoinositide 3-Kinase/Protein Kinase B (PI3 K/AKT), and Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2), contributing to the prevention and treatment of chronic diseases such as cancer, cardiovascular disorders, and inflammatory conditions. Species-specific characteristics, processing methods, and environmental factors significantly influence the bioavailability and efficacy of Allium-derived compounds. This review underscores the multifaceted health benefits of Allium species, highlights knowledge gaps, and identifies future directions for their clinical and pharmacological exploitation, aiming to bridge the gap between traditional applications and evidence-based therapeutics.