Roles and environmental modulation of chili pepper pungency
摘要
The sequencing of the Capsicum genus pangenome has stimulated interest in biotechnological strategies aimed at modulating pungency levels. While promising, such approaches require a comprehensive understanding of the ecological and physiological roles of capsaicinoids—the alkaloids responsible for pepper pungency. Although traditionally considered a defense against mammalian seed predators, accumulating evidence indicates that capsaicinoid biosynthesis is integrated into broader stress-response networks. Capsaicinoid production is influenced by genetic, ecological, and environmental factors, including light intensity, temperature, drought, and mineral nutrition, which dynamically regulate the biosynthetic pathway. Beyond defense, capsaicinoids perform internal physiological functions such as antioxidant protection, redox buffering, and nitrogen assimilation, framing pungency as a component of a coordinated metabolic strategy rather than a singular defensive trait. By connecting ecological pressures with molecular regulation, the dual ecological and physiological roles of capsaicinoid biosynthesis are emphasized, while knowledge gaps remain, particularly regarding non-Directed Deterrence Hypothesis (DDH) functions and tissue-specific expression of capsaicinoid genes. This integrated perspective provides a foundation for biotechnological interventions that modulate pungency without compromising plant resilience or metabolic homeostasis.