Viability and Biosynthetic Capacity of Immobilized Plant Cells

Abstract

Cells of the alkaloid-producing plant Catharanthus roseus, grown as suspension cultures, were immobilized by entrapment in various gels (1) and studied by monitoring plasmolysis, respiration, cell growth, and cell division. Cells entrapped in alginate, carrageenan, agarose and agar were found to be fully viable (1). Agarose-entrapped cells appeared to be essentially unaffected by immobilization as indicated by unrestricted respiration, cell growth, and cell division (Fig. 1A); while cells entrapped in alginate were restricted in respiration, cell growth, and cell division (Fig. IB). Viable preparations of immobilized plant cells were also biosynthetically active as shown by synthesis of the indole alkaloid ajmalicine (1). Both de novo synthesis and synthesis from added precursors took place. Enhanced alkaloid synthesis observed with alginate-entrapped cells in this and other (2) studies may result from secondary metabolite formation being proportional to the reciprocal of the growth rate.