Synthesis of citric acid using novel Aspergillus niveus obtained from agricultural wastes

Abstract
Fungus belonging to the genus Aspergillus is considered highly important in the production of various types of enzymes and organic acids. Aspergillus species produce organic acids such as citric acid, itaconic acid, and malic acid, which are one of the most important alternate techniques for chemical processes. Citric acid is an important component in the manufacturing process of food and beverages, pharmaceuticals, cosmetics, toiletries, detergents, and other industries. In this work, A.niveus was isolated from the agricultural waste collected in Kotagiri, The Nilgiris, India. Submerged batch fermentation with a range of low-cost substrates, such as wheat flour, corn starch, and sweet potato, was used to successfully synthesize citric acid by the isolated fungus. In addition, production-related factors such as substrate concentration and incubation time were optimized. The maximum yield of citric acid was produced using A. niveus from corn starch at a concentration 7of 120 g/L after 168 hours at pH 3.2. Furthermore, with a degree of extraction of 91.96, citric acid was extracted from fermentation.