Improving Secondary Metabolite Production in Tissue Cultures

Abstract

Plant cell and tissue culture has been suggested as an alternative means for year-round production of secondary metabolites with an added potential of increasing yields by culture selection and manipulation, genetic transformation, hairy root cultures, and use of bioreactors for mass production. Secondary metabolite pathways and genes involved in those pathways have been identified, and regulation of transcription and transcription factors has been determined by studying functional genomics in conjunction with data-mining tools of bioinformatics. Besides this, advances in metabolic engineering enable researchers to confer new secondary metabolic pathways to crops by transferring three to five, or more, heterologous genes taken from various other species. As an alternative, the metabolic pathways of useful secondary metabolites have been modified to improve their productivity via genetic transformation. However, there is a need to understand metabolic pathways of secondary metabolism at the molecular level. Plant hairy roots offer a novel and sustainable tissue-based system that preserves multiple specialized cell types believed to be important in maintaining a better consistency in synthesis of bioactive secondary molecules. This paper will review state-of-the-art reports on improving production of secondary metabolites in tissue cultures in various plant species.