Liu L, Dabrowski K, Ciereszko A
School of Natural Resources, Ohio State University, Columbus 43210, USA.
Mol Cell Biochem. 1995 Jul 5;148(1):59-66. doi: 10.1007/BF00929503.
The objectives of this study were to determine ascorbic acid stability and its effect on antiproteinase activity of seminal plasma in the presence of an oxidant. Effect of seminal plasma, and additives: glutathione, albumin, hydrogen peroxide and Tris buffer, on ascorbic acid degradation was investigated by UV absorbance. Antiproteinase against trypsin amidase activity was measured spectrophotometrically using N-benzoyl-DL-arginine-p-nitroanilide (BAPNA) as substrate. Ascorbic acid was destroyed much more rapidly with the addition of hydrogen peroxide than in Tris buffer at pH 8.2 alone. Seminal plasma protected ascorbic acid more efficiently than glutathione and albumin alone. The protective effect of seminal plasma on ascorbic acid degradation may closely relate to the function of ascorbic acid in reproductive system of scurvy-prone animals including teleost fish. Within the range of 1-8 mM concentrations, ascorbic acid had a pro-oxidant action on seminal plasma antiproteinase activity in vitro when they were incubated with hydrogen peroxide.
本研究的目的是确定在有氧化剂存在的情况下抗坏血酸的稳定性及其对精浆抗蛋白酶活性的影响。通过紫外吸收研究了精浆以及添加剂（谷胱甘肽、白蛋白、过氧化氢和Tris缓冲液）对抗坏血酸降解的影响。使用N-苯甲酰-DL-精氨酸对硝基苯胺（BAPNA）作为底物，通过分光光度法测定针对胰蛋白酶酰胺酶活性的抗蛋白酶。与仅在pH 8.2的Tris缓冲液中相比，添加过氧化氢后抗坏血酸的破坏要快得多。精浆比单独的谷胱甘肽和白蛋白更有效地保护抗坏血酸。精浆对抗坏血酸降解的保护作用可能与抗坏血酸在包括硬骨鱼在内的易患坏血病动物的生殖系统中的功能密切相关。在1-8 mM浓度范围内，当抗坏血酸与过氧化氢一起孵育时，其在体外对精浆抗蛋白酶活性具有促氧化作用。
