Biochemical Evaluation Of Selected Heavy Metal-Induced Inhibition On Chicken Liver Sorbitol Dehydrogenase
Journal of the Institute of Science and Technology, vol.16, no.1, pp.233-242, 2026 (Scopus, TRDizin)
- Publication Type: Article / Article
- Volume: 16 Issue: 1
- Publication Date: 2026
- Doi Number: 10.21597/jist.1717204
- Journal Name: Journal of the Institute of Science and Technology
- Journal Indexes: Scopus, TR DİZİN (ULAKBİM)
- Page Numbers: pp.233-242
- Keywords: Chicken liver, Enzyme inhibition, Heavy metal, Polyol pathway, Sorbitoldehydrogenase
- Open Archive Collection: AVESIS Open Access Collection
- Anadolu University Affiliated: Yes
Abstract
Sorbitol dehydrogenase (SDH) serves as a critical enzyme in the polyol pathway, an alternative metabolic route diverging from glycolysis. In this study, SDH was extracted and purified from chicken liver using a two-step chromatographic procedure involving DEAE-Sephadex anion exchange chromatography followed by Sephadex G-100 gel filtration. Molecular characterization determined that the enzyme’s subunit weight is approximately 41.4 kDa, while the native enzyme exists as a tetramer with a total molecular weight of 169 kDa, as confirmed by SDS-PAGE and gel filtration analyses. The enzyme exhibited peak catalytic activity under alkaline conditions, with an optimal pH of 9.0 and a temperature optimum of 50°C. The inhibitory impact of several heavy metal ions—including Cd²⁺, Pb²⁺, Hg²⁺, Ag⁺, Zn²⁺, and Ni²⁺—on SDH activity was evaluated. Among these, cadmium ions demonstrated the most potent inhibition, with an IC₅₀ value of 0.006 mM. Further studies using Lineweaver-Burk plots showed that the inhibition values were 0.07033 ± 0.00287 mM for Cd²⁺, 0.18033 ± 0.04879 mM for Pb²⁺, and 2.112 ± 0.03716 mM for Zn²⁺. The data unequivocally identify Cd²⁺ as the most effective inhibitor of sorbitol dehydrogenase (SDH) among the heavy metals analyzed, characterized by its remarkably low IC₅₀ value.