莲子多酚氧化酶的酶学性质

Enzymatic properties of polyphenol oxidase from Lotus seed

摘要: 以新鲜莲子为原料制备莲子多酚氧化酶（Polyphenol Oxidase,PPO）粗酶液,探讨莲子PPO酶学性质。结果表明:莲子PPO的活性最适温度范围为45⁵0℃、活性最适pH范围为6.5⁷.0,即中性时PPO的稳定性最高;而金属离子对其活性的影响显示出Ca2+、Mn2+、Fe3对莲子PPO酶活性具有一定的促进作用,铜离子则表现出较强的抑制作用;还原剂亚硫酸氢钠和亚硫酸钠对莲子PPO酶活性都有抑制作用。本研究旨在为有效抑制鲜莲褐变提供理论依据。

Abstract: Fresh Lotus seeds were used as raw materials to prepare and characterize crude polyphnol oxidase (PPO) extract. The results showed that PPO enzymes from Lotus seeds had the highest activity at 45⁵0℃ and pH 6.5⁷.0, the enzyme had the highest stability when pH was neutral. Ca2 +、Mn2 +、Fe3were effective in promoting PPO activity. Copper ion was highly effective in inhibiting PPO activity. PPOs were inhibited by reductants, such as sodium bisulfite and sodium sulfite. The purpose of this study was to provide a theoretical basis for inhibiting lotus seeds from browning effectively.