keywords: Arginase, benign tumour, malignant tumour, fibroid tissue, index of cancer
Arginase activity has been reported to be high in various cancers and the possibility of the use of this enzyme as index of malignancy in cancerous tissues has being considered. This research work is aimed at finding out if arginase activity is also increased in fibroid and therefore could be used as index too. Human fibroid tissues were obtained with ethical permit from the State Hospital, Sokenu, Abeokuta, Ogun State. Arginase was isolated and purified to apparent homogeneity using ammonium sulphate precipitation, chromatograpy on DEAE-Sephacryl, Reactive Blue Agarose affinity gel andgel filtration on Biogel P-100. The enzyme had a specific activity of 1.712 U/mg, Km of 47.62 mM and Vmax of 2.27 µmolurea/ml/min. The apparent molecular and subunit molecular weight was estimated to be 104,000 Da and 34,000 Da, respectively. The activity of the enzyme was not affected by Ba2+, Ca2+, K+, and Mg2+ but inhibited by Na+, NH and Hg2+. The enzyme had an optimum temperature of 50oC and pH of 8.5. Result from this study showed that the activity of arginase from fibroid tissue is quite small compared to that from many benign and malignant cancers, therefore, cannot be used as bioindicator for fibroid tissue.