ARS | Publication request: Spearmint plantlet culture system as a means to study secondary metabolism

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: June 1, 2008
Publication Date: June 1, 2009
Citation: Tisserat, B., Berhow, M.A., Vaughn, S.F. 2009. Spearmint Plantlet Culture System as a Means to Study Secondary Metabolism. Methods in Molecular Biology. 547:313-324.

Interpretive Summary: Mint species readily produce commercially important aromatic compounds, both in the whole plant or in culture. In an effort to study the influence of various physical and nutritional compounds on plantlet growth and secondary metabolism, a micro plantlet culture was constructed. Procedures to employ micro amounts of plant material to analyze for plant products are discussed. These procedures allow for testing small populations with confidence and avoid the sacrifice of large amounts of foliage and larger plant populations. We demonstrate how the micro plantlet culture system can readily manifest large levels of secondary metabolites using various test treatments. The information gained from these studies can be employed to improve the secondary product yield in plants grown in the field.

Technical Abstract: Spearmint has one major monoterpene, (-)-carvone, that constitutes up to 90 % of all the monoterpenes present. Likewise, rosmarinic acid accounts for up to 70 % of the phenylpropanoids produced from the plant. These two compounds are each produced by separate distinct biosynthetic pathways, which provide an excellent opportunity to study the influence of a wide number of environmental and chemical conditions on secondary metabolism and plant growth. The techniques presented in this paper employ one gram of fresh weight material for each secondary metabolite analyses. Analysis of single compounds obtained from the two distinct metabolic pathways simplifies the interpretation of the metabolic results, allowing for direct correlations of culture factors on secondary metabolism.