DefinePK

Abstract

Background:   Non-toxic, non-volatile organic acid, gluconic acid (pentahydroxycaproic acid) is found in abundance in honey and plants and in wines. Gluconic acid and its salts are used widely in food, feed, pharmaceuticals, textiles, and many other industries. Methods:  In the current investigation,  Aspergillus niger  was utilized for Gluconic acid production in submerged fermentation. Furthermore, for Gluconic acid hyperproduction, the fungus  Aspergillus niger  was exposed to MNNG (100 µg/ml) for 15 minutes.  Aspergillus niger  strain (parent and mutant) was tested and identified for its capability of producing gluconic acid. We finished the molecular identification, in which we extracted the DNA from the   A. niger  and amplified its ITS region using specific primers. We further sequenced the amplified product and created a phylogenetic tree employing the MEGA6 software. Results:  The tree results showed that our target sequence has 100% identity with  Aspergillus niger , which proved that the isolated strain belongs to the  Aspergillus   genera . In addition, factors related to the production of gluconic acid were confirmed by cultivating the mutant strain  A. niger  (MG1) and the parent strain under several conditions. These included varying the pH (4-7), temperature (30-40°C), and the concentration of the carbon source (40-100 g/l). The outcomes displayed that the best pH was 5. The most favorable temperature was 30°C, and maximum production occurred at a carbon source concentration of 100 g/l, for both mutant and parent strains. Conclusion:  This study shows how microbial strains and substrates could be used to attain cost-effective hyperproduction of gluconic acid to achieve objectives of industrial significance.  Keywords: Gluconic Acid;  Aspergillus niger ; Hyper-production; Mutation; Molecular identification; Sequencing