Production of triterpenoids from Ganoderma lucidum: Elicitation strategy and signal transduction

Ganoderic triterpenoid (GT) is a promising anti-tumour constituent of Ganoderma lucidum. GT accumulation occurs following stressors that include various elicitors or signalling molecules. Understanding the signal transduction pathways underlying elicitor-induced GT production will be helpful for commercial GT production. In this study, the activation of GT biosynthetic genes and GT accumulation mediated by biotic and abiotic elicitors will be investigated. Jasmonic acid (JA) is a well-known signalling molecule that is primarily involved in GT accumulation. Ca2+ spiking and reactive oxygen species (ROS), nitric oxide (NO) and cAMP production are other messengers that mediate GT production. This review highlights the elicitation strategies for GT production based on the principle of putative signal transduction pathways and the fundamental role of JA, ROS, NO, Ca2+, cAMP and their crosstalk in G. lucidum cells. In the future, elucidating the regulatory networks that control the secondary metabolite biosynthesis is therefore an important goal to manipulate the accumulation of GT.