Submerged Fermentation of Jatropha curcas Seedcake in Production of Itaconic Acid by Aspergillus niger and Aspergillus terreus

In
this study, two fungi: Aspergillus niger (ATCC
16404) and Aspergillus terreus (ATCC
20542) were used to ferment Jatropha
seed cake (JSC) by submerged fermentation for the production of itaconic acid.
The physico-chemical analysis of JSC was determined. JSC was shelled, defatted
and used as substrate in mineral salts media and the inocula of A. niger and A. terreus for eleven days at pH 5.42, 29±2°C, 10%
substrate and 2 ml inocula (2.6 x 108 spores/ml A. niger) (3.7 x 108 spores/ml A. terreus). Carboxylmethylcellulose (CMC) was used as control.
Optimization experiments were conducted by varying fermentation parameters.
Results of the physico-chemical analysis revealed carbohydrate 16.23%; protein
29.3%; fibre 10.42%; fat 32.13%; ash 5.75% and moisture 6.15%. Itaconic acid
yields of 154.0 g L-1 and 208.0 g L-1 were produced by A. niger and A. terreus respectively. Results of the optimization showed higher
yields of itaconic acid by A. niger to
209.0 g L-1 at pH 2.5, 3 ml inocula, 25% substrate, at 26±2°C on Day 8 and A. terreus yielded of 218.0 g L-1 at pH 3.5,
4ml inocula, 25% substrate at 29±2° C on Day 8. These results
support potential of JSC for industrial production of itaconic acid.