School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Food Funct. 2018 Jan 24;9(1):107-116. doi: 10.1039/c7fo01174a.
In this study, walnut meal hydrolysates (WMH) and dephenolized walnut meal hydrolysates (DWMH) were found to effectively decrease the serum uric acid level and protect the renal function in potassium oxonate-induced hyperuricemic rats in vivo as well as inhibit xanthine oxidase in vitro. Two novel antihyperuricemic peptides including WPPKN (640.8 Da) and ADIYTE (710.7 Da) were purified from DWMH via Sephadex G-15 gel filtration and reverse-phase high-performance liquid chromatography and identified by LC-ESI-MS/MS. These peptides displayed high in vitro xanthine oxidase inhibition (XOI) activity with IC values of 17.75 ± 0.12 mg mL (WPPKN) and 19.01 ± 0.23 mg mL (ADIYTE). Based on the results of molecular simulation, WPPKN entered into the hydrophobic channel and even obstructed the interaction between xanthine and xanthine oxidase (XO), while ADIYTE was positioned on the surface of the B-chain and blocked the entrance of the substrate to the hydrophobic channel. Therefore, the two peptides are partially responsible for the antihyperuricemic properties of DWMH.
在这项研究中，发现核桃粕水解物（WMH）和去酚核桃粕水解物（DWMH）在体内可有效降低尿酸盐诱导的高尿酸血症大鼠的血清尿酸水平，保护肾功能，在体外抑制黄嘌呤氧化酶。两种新型的抗高尿酸肽，包括 DWMH 中的 WPPKN（640.8 Da）和 ADIYTE（710.7 Da），通过 Sephadex G-15 凝胶过滤和反相高效液相色谱法进行分离纯化，并通过 LC-ESI-MS/MS 进行鉴定。这些肽显示出高的体外黄嘌呤氧化酶抑制（XOI）活性，IC 值分别为 17.75 ± 0.12 mg mL（WPPKN）和 19.01 ± 0.23 mg mL（ADIYTE）。基于分子模拟的结果，WPPKN 进入疏水性通道，甚至阻碍了黄嘌呤和黄嘌呤氧化酶（XO）之间的相互作用，而 ADIYTE 位于 B 链的表面，阻止了底物进入疏水性通道。因此，这两种肽部分负责 DWMH 的抗高尿酸血症特性。
