野桑蚕多酚氧化酶分离纯化的试验初报

A Preliminary Report on Extraction and Purification of Polyphenol Oxidase From Bombyx mandarina

多酚氧化酶是昆虫初生新表皮硬化过程中的关键性酶。为有利于研究野桑蚕(Bombyxmandarina)多酚氧化酶的功能与性质,探讨了野桑蚕多酚氧化酶的分离纯化方法。以野桑蚕5龄幼虫为材料,用磷酸盐缓冲液浸提多酚氧化酶粗提液,再经40%饱和度硫酸铵沉淀、透析及Sephadex G-100凝胶过滤进一步分离纯化,得到了部分纯化的多酚氧化酶,其酶纯化倍数为57.14倍±0.19倍,酶得率为10.17%±0.18%,酶比活力为(10 166.67±66.16)U/mg。采用该试验方法可有效分离纯化野桑蚕多酚氧化酶。

Polyphenol oxidase is a key enzyme involved in the sclerotization of new cuticular layer of insect. In order to study the function and characters of polyphenol oxidase from the wild silkworm Bombyx mandarina,isolation and purification methods of polyphenol oxidase from Bombyx mandarina were approached. Crude polyphenol oxidase was extracted from the 5th instar larvae with sodium phosphate extraction buffer. Partially purified polyphenol oxidase was obtained after precipitation with 40% saturated （NH4）2SO4, dialysis, and Sephadex G-100 gel filtration from the crude enzyme. This protocol had a purification factor of 57. 14 ±0. 19 and a yield factor of （10. 17 ± 0. 18）%, and the obtained enzyme had a specific activity of （10 166. 67 ±66. 16） U/mg, indicating that this protocol is effective for isolation and purification of oolvohenol oxidase from Bombvx mandarina.