Fumaric acid, an organic acid with a trans-double bond and
two carboxylic acid groups, is an important specialty chemical
with wide industrial applications, including uses as food acidulants
and in the synthesis of polymeric resins [1,2]. Fumaric acid
can be readily transformed into other C4 chemicals including malic
acid, succinic acid and aspartic acid [3], and has been identified
by the U.S. Department of Energy as one of the “top 12” buildingblock
chemicals that can be produced from renewable biomass [4].
Currently, fumaric acid is mainly produced via petroleum-based
chemical synthesis. However, limited petroleum resources, rising
oil prices, and concerns of environmental pollution caused by
chemical synthesis have prompted renewed interests in fumaric
acid production from sugars by fermentation using filamentous
fungi, Rhizopus oryzae and Rhizopus arrhizus [1–5].
However, the filamentous fungal fermentat