M.A. Thesis:

valuation of pectinase enzyme levels in biomass of aspergillus niger

Introduction: Pectinase enzyme has diverse industrial application. On the other hand, optimal production of this enzyme has been considered in recent years. The global market of industrial enzyme is progressing and biotechnology has played a prominent role in this field. Pectinase is one of the important enzyme in this industry, which is widely used in the industrial processing of fruits and vegtables. The aim of the present study was to evaluate the amount of pectinase enzyme in the biomass of aspergillus niger. Methodology: In this experimental study, the culture medium containing corn and corn bran was used for the propagation of the microorganism. Aspergillus niger strains was grown in culture medium. For this purpose, the spores in the screw cap were weighed and mixed with 80% Tween solution and deionized water. Fermentation medium preparation and purification were done to measure enzyme activity. The effect of carbon, nitrogen and sulfur sources on pectinase production in Aspergillus niger was investigated. Results: Aspergillus niger was characterized. Glucose, maltotriose and chitobiose were found to be the best sources for Aspergillus niger to produce pectinase enzyme. The best source of nitrogen for pectinase production was the medium containing 16 grams per liter of ammonia and urea, followed by nitro acid and nitric in the next position in terms of growth. The best source of sulfur in the culture medium for the growth of Aspergillus niger was the medium containing 14 grams per liter of sulfur and sulfate sources. Sulfite and sulfide were in the next positions. Conclusion: a considerable amount of pectinase enzyme was produced under optimal conditions from Aspergillus niger.

Keywords: Keywords: Aspergillus niger, pectinase enzyme, optimizing the culture medium