Comprehensive review of biosynthesis, plant function, metabolism and new therapeutic bioactivities of flavonoids.

Abstract

Background and purpose: Flavonoids are polyphenolic secondary metabolites synthesized via the phenylpropanoid pathway, serving as a vital biological "immune system" for plants by providing UV-B protection, antimicrobial defence, and pollinator attraction.

Experimental approach: This review examines how these plant-based survival tools translate into potent therapeutic agents for human health through a literature review using Google Scholar, Scopus and ScienceDirect, with keywords alone or in combination with other terms.

Key results: Current research demonstrates that flavonoids possess diverse bioactivities, including antioxidant, anti-inflammatory neuroprotective properties, with significant efficacy in mitigating cardiovascular disease, diabetes and cancer. Despite these benefits, the clinical application of flavonoids is currently hindered by limited bioavailability, which prevents consistent therapeutic concentrations in the human body, and a lack of standardized regulatory dosing.

Conclusion: This paper identifies three critical pillars for future innovation in the development of structural analogs to (a) improve intestinal absorption, (b) explore drug synergy for enhancing conventional medical treatments and (c) evaluate the microbiome interactions to facilitate personalized nutrition. By integrating plant biochemistry with clinical pharmacology, flavonoids can be transitioned from general dietary components into precise, evidence-based therapies.