Spearmint plantlet culture system as a means to study secondary metabolism.

Spearmint has one major monoterpene, (-)-carvone, that constitutes up to 90% of all the monoterpenes present. Likewise, the major phenylpropanoid-rosmarinic acid-in spearmint 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 chapter employ 1 g 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.