Insights into secondary metabolites and health promoting effects of edible flower Hemerocallis citrina Baroni

Edible flower of Hemerocallis citrina Baroni (H. citrina), commonly known as "Huang Huacai" in China, is a medicinal and edible vegetable with high nutritional value. Two major kinds of secondary metabolites identified in H. citrina flower are flavonoids and phenolic acids. H. citrina flower have been found to possess beneficial effects including anti-inflammatory, antioxidant, anticancer, antidepressant, antimicrobial, anti-constipation, anti-aging, sleep-improving, and lactation-promoting effects. These health benefits are carried through various mechanisms with different signaling pathways. However, the research on identification and mechanism of other types phytochemicals for H. citrina flower are not systematic and in-depth. In addition, the antidepressant actions show more significant effects in H. citrina flower, providing new insights for future clinical medicine development. This reviews the current research status of the secondary metabolites and health promoting effects of H. citrina edible flower, providing theoretical basis for the exploitation and utilization of H. citrina edible flower resources.