Ma Ke, Cui Jun-Zhu, Ye Jian-Bin, Hu Xian-Mei, Ma Ge-Li, Yang Xue-Peng
School of Food and Biological Engineering, Henan Provincial Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road, Zhengzhou 450002, People's Republic of China.
School of Food and Biological Engineering, Henan Provincial Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road, Zhengzhou 450002, People's Republic of China.
Food Chem. 2017 Sep 1;230:291-294. doi: 10.1016/j.foodchem.2017.03.057. Epub 2017 Mar 12.
A bioassay-guided fractionation of extract from Gluconobacter oxydans fermentation broth afforded Compound 1, which was identified as pyrroloquinoline quinone (PQQ) by spectroscopic methods. PQQ has been shown to enhance the superoxide anion-scavenging capacity significantly for Cu/Zn-SOD. To illustrate the mechanism, the interaction between PQQ and Cu/Zn-SOD was investigated. The multiple binding sites involving hydrogen bonds and van der Waals force between PQQ and Cu/Zn-SOD were revealed by isothermal titration calorimetry. The α-helix content was increased in the Cu/Zn-SOD structure with the addition of PQQ into the solution through ultraviolet (UV) spectroscopy. These results indicated that PQQ could change the conformation of Cu/Zn-SOD through interaction, which could enhance its superoxide anion-scavenging capacity. Therefore, PQQ is a potential natural antioxidant.
对氧化葡萄糖酸杆菌发酵液提取物进行生物测定导向的分级分离，得到了化合物1，通过光谱方法鉴定其为吡咯喹啉醌（PQQ）。已表明PQQ能显著增强铜/锌超氧化物歧化酶（Cu/Zn-SOD）的超氧阴离子清除能力。为阐明其机制，研究了PQQ与Cu/Zn-SOD之间的相互作用。等温滴定量热法揭示了PQQ与Cu/Zn-SOD之间存在涉及氢键和范德华力的多个结合位点。通过紫外光谱法发现，向溶液中添加PQQ后，Cu/Zn-SOD结构中的α-螺旋含量增加。这些结果表明，PQQ可通过相互作用改变Cu/Zn-SOD的构象，从而增强其超氧阴离子清除能力。因此，PQQ是一种潜在的天然抗氧化剂。
