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从豆壳抽提液经硫酸铵分级沉淀，ＤＥＡＥ－ＳｅｐｈａｄｅｘＡ－５０离子交换层析，ＣｏｎＡ－Ｓｅｐｈａｒｏｓｅ４Ｂ亲合层析和Ｂｉｏ－ＧｅｌＰ－６０凝胶过滤，纯化了豆壳过氧化物酶（ｓｏｙｂｅａｎｈｕｌｐｅｒ－ｏｘｉｄａｓｅ，ＳｈＰ）．纯化酶的比活力为７０７７Ｕ／ｍｇ，在ＳＤＳ－ＰＡＧＥ上显示出一条蛋白质带．ＳｈＰ分子量为３８０００，等电点为３．９；ＳｈＰ为一含血红素的糖蛋白，含糖量为１８．７％，光谱学分析揭示，在４０６ｎｍ处有一典型的Ｓｏｒｅｔ带，在５１０ｎｍ和６４０ｎｍ处有特征吸收峰．酶反应的最适ｐＨ在４．０附近，最适温度为４５℃；在ｐＨ２．５～１２．０之间较稳定，７５℃，保温６０ｍｉｎ，酶活力残余６８％，ＳｈＰ是一种良好的耐酸碱、耐热过氧化物酶．动力学分析求得ＳｈＰ的表观Ｋｍ（愈创木酚）为１．６２ｍｍｏｌ／Ｌ，表现Ｋｍ（Ｈ２Ｏ２）为０．３４ｍｍｏｌ／Ｌ．在所测定的化学试剂中，Ｎ－３、ＣＮ－、Ｆｅ３＋、Ｆｅ２＋和Ｓｎ２＋对酶有较强烈的抑制作用，而重金属离子Ａｇ＋、Ｈｇ２＋、Ｐｂ２＋、Ｃｕ２＋、Ｃｒ３＋以及ＳＤＳ和ＥＤＴＡ对酶活力无显著影响
The soybean hull peroxidase (soybean hull) was purified from soybean hull extract by ammonium sulfate fractionation, DEAE-Sephadex A-50 ion exchange chromatography, ConA-Sepharose 4B affinity chromatography and Bio-GelP-60 gel filtration. oxidase, ShP). The specific activity of the purified enzyme was 7077 U / mg, showing a protein band on SDS-PAGE. ShP has a molecular weight of 38,000 and an isoelectric point of 3.9; ShP is a heme-containing glycoprotein with a sugar content of 18.7%. Spectroscopic analysis revealed a typical Soret band at 406 nm at 510 nm and 640 nm There are characteristic absorption peaks. The optimum pH of the enzyme reaction was around 4.0 and the optimum temperature was 45 ℃. The pH was between 2.5 and 12.0, stable at 75 ℃ and 60 ℃ for 60min, and the residual enzyme activity was 68%. ShP was a good Acid, heat-resistant peroxidase. Kinetic analysis showed that the apparent Km (guaiacol) of ShP was 1.62 mmol / L and the Km (H2O2) was 0.34 mmol / L. Among the chemical reagents tested, N-3, CN-, Fe3 +, Fe2 + and Sn2 + had a stronger inhibitory effect on the enzyme, while the activities of heavy metal ions such as Ag +, Hg2 +, Pb2 +, Cu2 +, Cr3 + influences