Determinants of Yield of Secondary Products in Plant Tissue Cultures

Abstract

Plant tissue cultures have long been regarded as a source of commercially important steroids, alkaloids, colorings, flavors, fragrances, and terpenes for the pharmaceutical, cosmetic, and food industries. This chapter assesses the recent work on the factors controlling the synthesis of secondary products in plants. The nutrient media for plant tissue cultures consists of a carbon source, inorganic nutrients, both macro and trace elements, vitamins, amino acids and growth regulators. All the major components seem to have been tested for their effect on secondary product formation. The culture conditions are then assessed: light, temperature, and cell immobilization. Light, either as a specific wavelength or as white light, has been found to have an important role in stimulating secondary product formation in plant tissue cultures. When the cells are grown at a reduced temperature there appears to be a change in the production of secondary products. The effect of temperature on secondary product synthesis may also provide a useful way of investigating the control mechanism involved in secondary pathways. Immobilization of cells is a technique that has been used with both microbial and plant cells as to provide a more stable, uniform environment.