ABSTRACT

Citric acid is a ubiquitous intermediate product of metabolism and is found in practically all plants and animals. The aim of the study was to utilize orange peel as biomass for the production of citric acid using A. niger. Samples of   orange (Citrus sinensis) peels were obtained from a national citrus processing plant and was processed. The study revealed the presence of Aspergillus niger isolated from soil was able to produce citric acid from dried orange peels. The effect of inoculum concentration on citric acid production from the present study revealed that at 96hrs of incubation the inoculum concentration increased to 0.93g/L of 0.30g/L optical density while yield of citric acid from varying amounts of the fruit peel obtained were 0.42g/L, 0.66g/L, 0.73g/L, 0.81g/L and 1.04g/L respectively. In conclusion the production of citric acid using peels by Aspergillus niger has been reported to be easy, economical and eco-friendly. This method produced fairly high yield of citric acid and also it is an effective waste management method for the production of citric acid in the food and pharmaceutical industries.