2026-10-19T01:08:07Zhttps://ebyu-rdlopen.rawdatalibrary.net/oai/requestoai:ebyu-rdlopen.rawdatalibrary.net:ebyu/161072026-10-18T20:36:52Zopenairedrivercom_ebyu_10000col_ebyu_10001Effects of some vitamins on lactoperoxidase enzyme activitySisecioglu, MeldaCankaya, MuratOzdemir, HasanBovine milkInhibitionLactoperoxidaseVitaminsAnimalsAscorbic AcidCattleEnzyme InhibitorsFemaleFolic AcidInhibitory Concentration 50KineticsMilkVitamin K 3Bovinaemenadione sodium bisulfitearticleenzyme activityenzyme inhibitionenzyme purificationgel filtration chromatographyion exchange chromatographynonhumanpolyacrylamide gel electrophoresisObjective: The present paper investigates the in vitro effect of L-ascorbic acid (vitamin C), menadione sodium bisulfate (vitamin K3), and folic acid on purified lactoperoxidase (LPO). Methods: This enzyme was purified from bovine milk by AmberliteCG50 resin,CMSephadex C-50 ion-exchange chromatography, and Sephadex G-100 gel filtration chromatography. Results: Rz (A412/A280) value for the purified LPO was found to be 0.8. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDSPAGE) method and a single band was observed. All tested vitamins caused inhibition of the enzyme activity and displayed a competitive type of inhibition mechanism. IC50 values of these three vitamins were 2.03 μM, 0.025 mM, and 0.0925 mM, and the K i constants were 0.508±0.257 μM, 0.0107±0.0044 mM, and 0.0218±0.0019 mM respectively. Conclusion: The vitamins discussed here displayed inhibition-type competition with LPO enzyme at varying concentrations. Our study showed that L-ascorbic acid exhibited a much higher inhibitory effect at lower concentrations, so it was evidently a more potent inhibitor than other vitamins tested. © Hogrefe & Huber Publishers.VERLAG HANS HUBER2009Articlehttps://rdlopen.rawdatalibrary.net/r/ebyu/16107https://doi.org/10.1024/0300-9831.79.3.1880300-9831enInternational Journal for Vitamin and Nutrition Researchinfo:eu-repo/semantics/openAccessinfo:eu-repo/semantics/articlehttps://ebyu-rdlopen.rawdatalibrary.net/tr/items/ebyu/16107