RESUMEN
The bioconversion of lignocellulosic materials for organic acid had great meaning to both economic and social benefit,owning to its renewable character,abundance and low price.In order to find out the key to the efficient utilization of lignocellulose,kinds of fermentation strategies to product organic acid(such as loctic acid,funaric acid)from lignocellulcsic were discussed,also the xylose metabolic pathway of Rhizopus sp.was extensively reviewed,and it find out that the low conversion of xylose was the bottle-block.
RESUMEN
A stable and efficient L-Malic acid accumulation mutant strain Rhizopus oryzae ME-M15 was discovered occasionally in the mutation breading for fumaric acid producers. Rhizopus oryzae ME-M15 gave a L-Malic acid output of 16.3 g/L on average after fermentation for 96 hours, more than 3 times than that of the parent strain ME-F10. In addition, other metabolites such as ethanol and fumaric acid were re-markably decreased in accordance with the depressed activity of the cytosolic isoenzyme of fumarase and alcohol dehydrogenase in strain ME-M15, while the activity of the pyruvate carboxylase had no significant difference.