Citric acid production by the solid-state fermentation potential of Aspergillus Niger using different substrate wheat straw, sugarcane waste and mixed from North Gondar area of Ethiopia

Abstract

Citrus fruits, of course, contain citric acid. Synthetic forms are frequently used as an extra ingredient and are made from a particular kind of fungi. There is a higher requirement for citric acid manufacturing because it is utilized in many advanced medical fields as well as the food and beverage industries. There is a dearth of prior research on the extraction of organic acids, such as citric acid, from filamentous fungi in Ethiopia. Therefore, the purpose of this work was to use wheat straw, sugarcane waste, and a combination as a substrate to manufacture citric acid from Aspergillus niger that was isolated from agricultural soils in Ethiopia's north Gondar zone. Aspergillus isolates were found in agricultural soil samples used in this investigation. The ideal pH and temperature for the chosen isolate to produce the most citric acid were also investigated. Morphological techniques were used for the initial identification of the chosen isolates. An isolate from a mixed substrate showed the highest citric acid output (1.6 g/100 ml) on basal screening media when the isolates were screened for citric acid synthesis. For this isolation to produce the most citric acid, the ideal conditions were 30°C, 129 hours, pH 6.5, and 70% moisture. This study suggests that A. niger, which was isolated from agricultural soil in Ethiopia's north Gondar zone, could generate more citric acid with a different substrate.