Purification of DPP-IV enzyme from porcine serum, is presented in this study for the first time. The high molecular weight DPP-IV from porcine serum was fractioned using Sephadex G-75 gel filtration followed by DEAE Sephadex anion exchange and Sephadex G-100 gel filtration chromatography columns with a final yield of 11.25%. The SDS-PAGE of the purified sample showed a single band of molecular mass nearing 160 kDa. Distinct single band was observed after PAS staining confirmed it to be a glycoprotein. The purified enzyme showed an optimum pH and temperature of 8 and 37 °C, respectively. The enzyme effectively cleaved fluorogenic substrate Gly-Pro-AMC with Km and Vmax of 4.578 µM and 90.84 nmoles/min, respectively. Purified DPP-IV activity was inhibited by Diprotin A with an IC₅₀ value of 8.473 µM. Among the three plant extracts used to study DPP-IV inhibition, the aqueous hot extract of Terminalia chebula showed the highest inhibition of 87.19%, followed by the aqueous cold extract of Momordica carantia, ( 31.6%) and Azadirachta indica (34.16%) at the concentration of 25 µg.

这项研究首次提出了从猪血清中纯化DPP-IV酶。使用Sephadex G-75凝胶过滤，然后进行DEAE Sephadex阴离子交换和Sephadex G-100凝胶过滤色谱柱，分离猪血清中的高分子量DPP-IV，最终收率为11.25％。纯化样品的SDS-PAGE显示单分子带接近160 kDa。在PAS染色确认它是糖蛋白后，观察到明显的单条带。纯化的酶的最佳pH值和温度分别为8和37°C。该酶有效切割荧光底物Gly-Pro-AMC，Km和Vmax分别为4.578 µM和90.84 nmoles / min。Diprotin A以IC ₅₀抑制纯化的DPP-IV活性值为8.473 µM。在用于研究DPP-IV抑制作用的三种植物提取物中，Terminalia chebula的水热提取物显示出最高的抑制率，为87.19％，其次是Momordica carantia的水冷提取物（31.6％）和Azadirachta indica（34.16％）。浓度为25 µg。