Virtual Conference
Food Science 2023

Joseph Peter Shaba

Air Force Institute of Technology, Nigeria

Title: Assessment of Purified and Characterized Urease from Three Sprouted Melon Varieties


Urease is an enzyme that catalyzes urea into ammonia and carbon dioxide. Large quantities of urease have been observed to be present in some species of the Cucurbitaceae family. This enzyme plays a major role in converting atmospheric nitrogen into absorbable form of nitrogen. The aim of this research is to purify and characterize urease from three sprouted melon varieties. The Melon seed samples was bought from lapai market, Niger state, Nigeria. The extraction of the enzyme was carried out in four steps which include precipitation, dialysis, Gel filtration chromatography and electrophoresis. The activity of the protein extracted was observed under changing pH, temperature and different metal ions. The molecular weight of the enzyme was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. The urease enzyme had a yield of 19.5, 18.4 and 19.2% and was purified 4.0, 2.5 and 1.6 fold for Black melon, water melon and white melon respectively. The optimum pH was found to be 6.0 for white and black melon while watermelon was 7.5, and the optimum temperature was found to be 30, 40 and 50°C for watermelon black melon and white melon respectively. The molecular weight of the enzyme shows three bands in white melon and water melon and was found to be approximately 55, 38, and 35kDa while black melon has no clear bands. The activity of the enzyme was enhanced by Ni2+ whereas inhibitory effects were observed in descending order from the following ions, Mg, Hg, EDTA Ba, Ca, and K. The urease enzyme from water melon, Black melon and white melon had Vmax of 0.000611, 0.000410 and 0.000163 U/Sec also with the Km of 0.0341, 0.0469 and 0.0021mg/ml respectively. The purified Urease can be immobilized and used as bio-marker for urea diagnosis in the medical laboratory.


Joseph Peter Shaba has completed his Master’s of Science (MSc.) Biochemistry at the age of 30 years from Ibrahim Badamasi Babangida University, Lapai. He has applied for His PhD at Brigham Young University and North Carolina State university both in USA awaiting admission. He has over 10 publications both locally and internationally that have been cited over 50 times, and his publication h-index is 2. He has been serving as member board of examiners at both departmental and  faculty  level of the University.