iarjcmbIARJCMBIARJCMB2789-6005https://doi.org/10.47310/iarjcmb.2025.v05i01.003Isolation and Partial Purification of Serum Arginase in Patients with Renal Failure and Controls: Comparative StudyArginase effectively treats kidney failure, as it removes excess urea produced by protein breakdown in the body. High levels of arginase may lead to the risk of kidney failure. Therefore, we studied this enzyme, isolating and purifying it from the serum of patients with chronic kidney failure. We determined the optimal conditions for its activity and molecular weight and partially purified it. The study included 40 patients of both sexes (22 males and 18 females). We performed the following purification steps: protein precipitation using 65% ammonium sulfate, followed by dialysis and the Sephadex G-100 gel technique. Statistics showed that the specific activity of crude engines was 0.57 and the specific activity increased 17-fold upon purification, reaching 9.7 (U/mg). The specific activity was purified 17-fold, with an extraction rate of 64.8%. The molecular weight of purified arginase was 97,000±1,400 Daltons. The highest activity level of purified arginase was achieved in 50 μL of patient serum, pH 9.5 and a buffer solution of 100 mM sodium barbitone and 200 mM arginine as an arginase substrate, at 37°C for 30 minutes. The study concluded that the specific activity of arginase extracted from the serum of patients with renal failure increased 17-fold after purification. The properties of arginase and the optimal conditions for its activity vary depending on the source from which the purified enzyme is extracted.