Bioactive Compounds from Allium Species: Chemical Features and Molecular Mechanisms in Polycystic Ovary Syndrome—A Narrative Review

Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disorder characterized by hyperandrogenism, insulin resistance, oxidative stress, and chronic low-grade inflammation, while conventional therapies are often limited by adverse effects and suboptimal adherence. This narrative review aims to evaluate the chemical composition and mechanistic effects of bioactive compounds derived from Allium species in the context of PCOS. A comprehensive analysis of the literature was performed, focusing on organosulfur compounds and polyphenols, with emphasis on their structure, reactivity, transformation pathways, and biological activity, integrating findings from preclinical and clinical studies. The evidence indicates that key compounds, including allicin, ajoene, and diallyl sulfides, exert biological effects through modulation of redox balance, inhibition of inflammation-related signaling, and regulation of insulin signaling pathways, while also influencing steroidogenesis and androgen synthesis. Polyphenolic compounds contribute primarily through antioxidant mechanisms related to their structural features. However, the current evidence remains limited by the scarcity of large-scale, long-term human clinical trials, particularly in women with PCOS, which restricts definitive conclusions regarding clinical efficacy, optimal dosing, safety, and long-term therapeutic applicability. Overall, Allium species represent a promising source of multitarget bioactive compounds for PCOS management, and understanding the chemical basis of their activity is essential for optimizing their therapeutic potential and guiding future research.