Fed-batch hairy root cultures with In Situ separation

Abstract

Fed-batch cultures of L. erythrorhizon hairy root were carried out by controlling sucrose concentration and media conductivity in a shake flask and a modified stirred tank reactor. For the efficient product recovery from the culture, in situ adsorption by XAD-2 was also conducted. When sucrose was used as a carbon source, the highest shikonin production and hairy root growth were obtained. When glucose or fructose was used instead, the growth was severely inhibited. In addition, it was found that alternating feeding of sucrose could be used as an effective strategy for enhancing the productivity of shikonin derivatives. As the XAD-2 amount was increased up to 1.5 g/L, shikonin production was enhanced by removing shikonin produced and other products which might be inhibitory to cell growth. Most amount of shikonin produced was successfully recovered in XAD-2 (Over 99%). Using hairy-root culture in a modified stirred tank reactor, the shikonin productivity and hairy root growth rate on the average were 9.34 mg/L · day and 0.49 g DCW/L · day, respectively.