Abstract: 88 plant species from 44 families were used as raw material to screen oxalate oxidase (OXO), from which, 60 species from 34 families showed detectable OXO activities, and 30 species showed quite high OXO activity amounting to >0.02 U/mg protein, and >0.2 U/g·fw. In order to evaluate the possibility of scavenging oxalate in mammalian body by OXO, five plant species with high biomass and OXO activity, namely, Echinacea purpurea, Patrinia villosa, Sarcandra glabra, Rhinacanthus nasutus and Glycyriza uralensis were chosen as candidates to study their characteristics. The OXOs from the above 5 plant species were all stable at high temperature and acid environment, and those from Echinacea purpurea, Rhinacanthus nasutus, and Patrinia villosa were not inhibited by NaCl and CaCl₂ or hydrolysised by pepsin, indicating a high application potential. The enzyme from Glycyriza uralensis was not inhibited by NaCl and CaCl₂ but sensitive to pepsin, while that from Sarcandra glabra was inhibited by NaCl and CaCl₂ as well as pepsin.

Key words: oxalate oxidase, screening, characteristic

摘要： 以44科88种植物叶片为酶源,检测出具有OXO活性的植物34科60种,其中OXO比活力较高(>0.02U/mg protein且>0.2U/g·fw)的有30种。为评估酶法清除动物体内草酸的可能性,研究了松果菊、白花败酱、草珊瑚、白鹤灵芝和甘草的OXO性质。结果表明,5种植物OXO都具有极强的酸、热稳定性;松果菊、白鹤灵芝和白花败酱OXO活性不受胃蛋白酶、NaCl和CaCl₂抑制,具有较好的应用潜力;甘草OXO活性不受NaCl和CaCl₂抑制,但受胃蛋白酶降解;而草珊瑚OXO受NaCl、CaCl₂及胃蛋白酶抑制。

关键词: 草酸氧化酶, 筛选, 性质