Plant peroxidases were found to play an important role in plant physiology such as the metabolism and transformation of small complexes. In the present research, a novel Momordica charantia peroxidase (MCP) from fruits was purified to electrophoretic homogeneity by combining consecutive treatment of ammonium sulfate fractionation, ion exchange chromatography on DEAE-Sepharose FF, affinity chromatography on concanavalin A (Con A) Sepharose and gel filtration on Sephadex G-150. The physical and chemical characters of MCP were also investigated. MCP catalyzed the oxidation of ferulic acid (FA) to dehydrodimer (FA-2) in aqueous acetone system at pH 5.0. Its structure was identified by spectral analyses including IR, 1H-, 13C-NMR and electrospray ionization mass spectroscopy (ESI-MS). The anti-inflammatory activities of FA, FA-2 and other derivatives were examined. FA-2 significantly inhibited the release of proinflammatory factors such as TNF-α, NO and proliferation of spleen cells induced by phytohemagglutinin (PHA) and Con A and promoted a greater DNA fragmentation of spleen cells than that of other complexes. These results suggested that MCP as a tool enzyme transformed some complexes such as FA to more active derivatives, and that FA-2 was a potential inhibitor on inflammation through interference with immune response in the process of inflammation, which maybe was associated with apoptosis of immune related cells induced by FA-2.
研究发现,植物
过氧化物酶在植物生理过程中发挥着重要作用,如小复合物的代谢和转化。在本研究中,通过
硫酸铵分馏、
DEAE-Sepharose FF 离子交换色谱、concanavalin A (Con A) Sepharose 亲和层析和 Sephadex G-150 凝胶过滤的连续处理,从果实中纯化了一种新型的 Momordica charantia
过氧化物酶(MCP),使其达到电泳均匀性。此外,还研究了 MCP 的物理和
化学特性。在 pH 值为 5.0 的
丙酮水溶液体系中,MCP 可催化
阿魏酸(FA)氧化为脱氢二聚体(FA-2)。通过红外光谱、1H-、13C-NMR 和电喷雾质谱(ESI-MS)等光谱分析确定了其结构。研究了 FA、FA-2 和其他衍
生物的抗炎活性。与其他复合物相比,FA-2 能明显抑制植物血凝素(PHA)和 Con A 诱导的 TNF-α、NO 等促炎因子的释放和脾细胞的增殖,并能促进脾细胞 DNA 断裂。这些结果表明,作为一种工具酶,MCP能将一些复合物(如FA)转化为更具活性的衍
生物,而FA-2是一种潜在的炎症
抑制剂,它通过干扰炎症过程中的免疫反应来抑制炎症,这可能与FA-2诱导的免疫相关细胞凋亡有关。