Downstream processing of red beet hairy roots

Abstract

Triggering cultured plant cells and organs to synthesize the highest possible extent of a particular metabolite is an advantage for its industrial-scale production. However, product recovery by smart techniques is equally important for the commercial success of the process. Considering the possibilities of in situ and ex situ product extraction methods, a large number of studies have focused on different modes of recovery of metabolites where intactness of molecules and their further stabilities have posed technological challenges. In red beet hairy roots, where chiefly betalains are of signi fi cance, reverse sequestration of vacuolar pigments into the cell exterior was accomplished by driving forces of both physical and chemical nature. Subsequent coupling technologies, such as pigment concentration by ex situ adsorption and simultaneous separation into red and yellow compounds during desorption, have also been successfully applied. Experiments conducted at bench-scale to standardize several unit operations were found adoptable for continuous process when such units were integrated. This chapter brings together research attempts made towards the recovery of betalains as well as the progress made towards developing strategic processes for the simultaneous recovery of betalains and peroxidase enzymes from red beet hairy roots grown in specialized bioreactors.