ABSTRACT
Levoglucosan is the main product derived from pyrolysis of cellulose. A mutant Aspergillus niger CBX-209 could grow on levoglucosan well fermenting it into citric acid with a yield comparable to that on glucose. Levoglucosan hydrolase was absent by measuring glucose formation with the glucose oxidase and peroxidase coupling system. Cell extracts were partly purified by ammonium sulfate fractionation and ion-exchange chromatograph. Direct formation of glucose 6-phosphate from levoglucosan in the presence of ATP and MgCl2 was observed when it was reacted with partly purified enzyme by a combined strategy of enzymological and fast atom bombardment mass spectrometric analysis. These data showed that the mutant used a novel enzyme, levoglucosan kinase, to convert levoglucosan into glucose 6-phosphate. Levoglucosan kinase was an inductive enzyme.
Subject(s)
Aspergillus niger , Metabolism , Enzyme Induction , Fermentation , Glucose , Metabolism , Glucose-6-Phosphate , Metabolism , Phosphorylation , Phosphotransferases , Spectrometry, Mass, Fast Atom BombardmentABSTRACT
Succinic acid is widely used in the field of chemistry and food proces s. Compared to the traditional chemical synthesis, succinic acid production by fermentation has some benefits. The new process with competitive cost uses rene wable agricultural resources including green house gas CO 2 instead of fossil f uels and reduces pollution from chemical synthesis. In this article, research progr e ss in production of succinic acid by fermentation such as microorganisms, metabo lic pathways and its regulation, fermentation and isolation are briefly reviewed .