Growth of transformed roots in a nutrient mist bioreactor: reactor performance and evaluation

Abstract

A nutrient mist bioreactor was modified for culturing transformed roots of Beta vulgaris and Carthamus tinctorius on a nylon support. Culture conditions of misting cycle, inoculum size, batch or continuous operation and sucrose concentration were varied in order to maximize growth over a 1-week period. Root tissue cultured in nutrient mists in a 1.8-1 culture chamber achieved levels of growth equivalent to hairy roots cultured in shake flasks with identical medium. Our resuits demonstrate the effectiveness of nutrient mist culture as applied to hairy roots, thereby providing an alternative means for successful culture of these tissues.

Trickle‐bed root culture bioreactor design and scale‐up: Growth, fluid‐dynamics, and oxygen mass transfer

“…result indicates that estimation of root growth based on weighing of a drained reactor (e.g., DiIorio et al, 1992aDiIorio et al, , 1992b could be in error by as much as 30-100%. Root morphology, extent of root hair formation, presence of gas down-flow, and bioreactor configuration will all contribute to differences in static hold-up.…”

Growth of Artemisia annua hairy roots in liquid‐ and gas‐phase reactors

“…In gas-phase reactors, roots are exposed to air and liquid nutrients are either sprayed onto the roots (Flores and Curtis, 1992;Singh and Curtis, 1994;Williams and Doran, 2000) or delivered as a mist of micron-sized droplets (Buer et al, 1996;DiIorio et al, 1992a;Weathers et al, 1999). Gasphase reactors can virtually eliminate any oxygen deficiency in dense root beds (Weathers et al, 1999) while also providing a low shear stress environment.…”

Design, Development, And Applications Of Mist Bioreactors For Micropropagation And Hairy Root Culture

“…CO 2 -enriched nutrient mist cultures of Carthamus tinctorius and Beta vulgaris hairy roots showed increased growth versus control cultures that were fed ambient air [60]. However, a similar effect was not observed in hairy roots of Artemisia annua.…”

“…Liu et al [69] provided gas either only when mist was not being generated, or continuously; while Weathers et al [5] provided gas only when the mist was provided. Interestingly, DiIorio et al [60] also observed that hairy roots seemed to have optimum mist duration for growth. Their studies with hairy roots of Beta vulgaris and Carthamus tinctorius showed that either increasing or decreasing the "off" time beyond a certain limit adversely affected root growth of those species.…”

“…Kim et al [55] also noted similar results where the biomass accumulation was similar between root cultures grown in ambient air and those supplemented with 0.5% CO 2 . It is possible that perhaps the optimum level of CO 2 enrichment for A. annua hairy roots was not provided to these cultures, particularly considering that the response of roots to CO 2 can vary depending on species and growth environment [1,60].…”