An overview of key industrial product citric acid production by Aspergillus niger and its application

Citric acid possesses high economic value and is considered as the world's largest consumed organic acid in numerous industries. Citric acid applications range from food to beverage industries, pharmaceuticals, cosmetics, and the environment. It is mostly produced by microbial fermentation but Aspergillus niger is considered as the main workhorse for large-scale production of citric acid. In the current review, special devotion has been made toward addressing the latest and innovative literature related to production of citric acid by A. niger using. The review article discussed A. niger historical involvement in citric acid production, fermentation technologies, molecular biology, biosynthesis, accumulation of citric acid, methods for enhanced production of citric acid, different operational factors also influencing citric acid production, and various techniques used for citric acid recovery. Also, copious biotechnological applications of citric acid are summarized for a fundamental comprehension of the subject and its critical role in diverse fields of industries.