Citric acid production by Aspergillus niger

The worldwide demand of citric acid is about 6×105 tons per year. Citric acid with an estimated annual production of 500000 tons is produced almost exclusively by fermentation with Aspergillus niger and widely used in food chemical pharmaceutical and other industries. Keeping in view production of citric acid was investigated in submerged fermentation using shake flask fermentation. Maximum product yield was achieved under optimum methanol concentration (1.5 %) and ethanol concentration (1.0%) which shows enhance improvement in citric acid production compared to the control strain without any lower alcohols treatment. The work done in the current study is a major contribution for optimization of different fermentation parameters for citric acid production however same process parameters may also be useful for production of different organic acids and enzymes in submerge fermentation system.