文摘
Vanillin production was tested with different concentrations of added ferulic acid in E. coliharboring plasmid pTAHEF containing fcs (feruloyl-CoA synthase) and ech (enoyl-CoAhydratase/aldolase) genes cloned from Amycolatopsis sp. strain HR104. The maximum productionof vanillin from E. coli DH5 harboring pTAHEF was found to be 1.0 g/L at 2.0 g/L of ferulicacid for 48 h of culture. To improve the vanillin production by reducing its toxicity, twoapproaches were followed: (1) generation of vanillin-resistant mutant of NTG-VR1 throughNTG mutagenesis and (2) removal of toxic vanillin from the medium by XAD-2 resin absorption.The vanillin production of NTG-VR1 increased to three times at 5 g/L of ferulic acid whencompared with its wild-type strain. When 50% (w/v) of XAD-2 resin was employed in culturewith 10 g/L of ferulic acid, the vanillin production of NTG-VR1 was 2.9 g/L, which was 2-foldhigher than that obtained with no use of the resin.