In vitro strategies for the enhancement of secondary metabolite production in plants: a review

BACKGROUND: Plants are the prime source of vital secondary metabolites (SMs) which are medicinally important for drug development, and these secondary metabolites are often used by plants in the various important tasks like defense against herbivory, interspecies defenses and against different types of stresses. For humans, these secondary metabolites are important as medicines, pigments, flavorings and drugs. Because most of the pharmaceutical industries are highly dependent on medicinal plants and their extraction, these medicinal plants are getting endangered. MAIN BODY: Plant cell culture technologies are introduced as a viable mechanism for producing and studying SMs of plants. Various types of in vitro strategies (elicitation, hairy root culture system, suspension culture system, etc.) have been considerably used for the improvement of the production of SMs of plants. For the enhancement of SM production, suspension culture and elicitation are mainly used, but hairy root culture and other organ cultures are proved to satisfy the demand of secondary metabolites. Now, it is easy to control and manipulate the pathways that produce the plant secondary metabolites. CONCLUSIONS: Techniques like plant cell, tissue and organ cultures provide a valuable method for the production of medicinally significant SMs. In recent years, most of the in vitro strategies are used due to knowledge and regulation of SM pathway in commercially valuable plants. In future, these things will provide a valuable method to sustain the feasibility of medicinal plants as the renewable sources of medicinally important compounds, and these methods will provide successful production of desired, important, valuable and also unknown compounds.