Elicitation strategies for enhanced secondary metabolite synthesis in plant cell cultures and its role in plant defense mechanism

Plants possess the remarkable ability to thrive in challenging environments by synthesizing a diverse array of specialized metabolites, which play crucial roles in defense against biotic and abiotic stresses. Despite their significance, the low natural yield of these bioactive compounds, coupled with genetic variability and environmental influences, poses significant challenges for their extraction and utilization. In recent years, plant tissue culture has emerged as a viable alternative for the controlled and consistent production of secondary metabolites. Among various strategies to boost metabolite synthesis in vitro, elicitation has proven to be the one of the most effective in triggering plant defense mechanisms and enhance secondary metabolite accumulation. This review comprehensively explores the role of elicitation in promoting secondary metabolite synthesis in plant cell cultures, with a particular focus on the mechanisms and regulatory functions of key elicitors like salicylic acid and methyl jasmonate. It delves into the classification of elicitors, their effects on various in vitro culture systems, and the potential of nanoparticles as novel elicitors. Additionally, the review discusses the co-culture technique as a promising strategy for biotechnological mining of secondary metabolites. The review also highlights the role of elicitation in improving stress tolerance in plants and emphasizes the need for continued research to overcome existing challenges and fully realize the potential of these strategies. This paper is a valuable resource for scholars and professionals in plant biotechnology, nanotechnology, and related fields, offering insights into the current state of knowledge, and future directions for enhancing secondary metabolite production in plants.