Antimicrobial Susceptibility of Clinical Isolates of Candida Species to Ethanolic Extracts of Ziziphus Abyssinica Leaves

1Nasir, M. S., 2*Mohammed, Y., 1Bukar, A., 1Mukhtar, M.D. and 3Umar, A. A.

1Department of Microbiology, Faculty of Life Sciences, Bayero University, Kano

 2Department of Medical Microbiology and Parasitology, Faculty of Clinical Sciences, College of Health Sciences, Bayero University, Kano, Nigeria

3Department of Community Medicine, Faculty of Clinical Sciences, College of Health Sciences, Bayero University, Kano, Nigeria

*Corresponding author:,


Pectinases are the group of enzymes that catalyzes the degradation of pectic substances. Pectinase are enzymes that are remarkably employed in most industries because they have a large variety of applications, such as increasing juice extraction by decreasing the viscosity of concentrates in cellulose fibre preparation, coffee/tea fermentation and also for the clarification of juices and wines. This research was carried out for pectinase production by Aspergillus niger AR2 using local orange peel as substrate. Aspergillus niger was isolated from spoiled orange fruit and identified using phenotypic and molecular techniques. The isolate was screened for pectinase production on pectin agar. Fermentation was carried out by Aspergillus niger AR2 at fermentation days 3, 4 and 5; the amount of substrate (15g), pH (5), temperature (300C) and inoculum density of 106 (spore/mL). After fermentation, crude pectinase was extracted for enzyme assay. Enzyme activity was measured based on the amount of D-galacturonic acid released by the crude enzyme. Pectinase produced was used for orange juice extraction from mashed oranges and compared with juice with no enzymes. The results have shown that maximum pectinase production by A. nigerAR2 was found to be at a temperature of 300C, inoculum density of 106 (spore/mL), pH 5 at day 5 using orange peels as substrate with an activity of 3.04±0.024 (U/ml). The result shows that the pectinase produced was effective in orange juice extraction from mashed oranges due to the increase in the volume of orange juice.


Aspergillus niger, Pectinase, Substrates Fermentation