ABSTRACT
Recently there has been an upsurge of interest in the therapeutic potential of medicinal plants, which might be due to their phenolic compounds, specifically flavonoids. Flavonoids are a group of secondary metabolites having different phenolic structures and are found in vegetables, fruits, stems, flowers, bark, grains, and roots of plants. These natural compounds exhibit various biological activities like antioxidant, anti-mitogenic, anti-inflammatory, anticancer, and immunomodulatory effects complied with their capacity to modulate cellular enzyme functions. Among dietary factors, flavonoids have great potential as diet-derived immune-modulatory chemopreventive agents that might be of importance to several cancers. They regulate immunity by interfering with the regulation of immune 144cells, synthesis, and secretion of various proinflammatory cytokines and gene expression. Flavonoids and their derivatives modulate various transcriptional factors, differentiation, proliferation, and activation of immune cells. The versatile health benefits of flavonoids in various epidemiologic studies will provide newer insights and will certainly lead to a new era of flavonoid-based pharmaceutical agents for the treatment of many infectious and degenerative diseases. The present review focuses on the immuno-enhancing potential of various bioactive flavonoids isolated from natural sources and their mechanism of action.
