评价 PBN 自旋捕获自由基作为蛋黄酱中脂质氧化早期标志物。

Evaluation of PBN spin-trapped radicals as early markers of lipid oxidation in mayonnaise.

机构信息

Unilever Food Innovation Centre, Bronland 14, 6708 WH Wageningen, The Netherlands; Wageningen University & Research, Laboratory of Food Chemistry, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands; Wageningen University & Research, Laboratory of Biophysics, Stippeneng 4, 6708 WE Wageningen, The Netherlands.

Wageningen University & Research, Laboratory of Food Chemistry, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.

出版信息

Food Chem. 2021 Jan 1;334:127578. doi: 10.1016/j.foodchem.2020.127578. Epub 2020 Jul 18.

DOI:10.1016/j.foodchem.2020.127578

PMID:32721836

Abstract

Quality deterioration of mayonnaise is caused by lipid oxidation, mediated by radical reactions. Assessment of radicals would enable early lipid oxidation assessment and generate mechanistic insights. To monitor short-lived lipid-radicals, N-tert-butyl-α-phenylnitrone (PBN), a spin-trap, is commonly used. In this study, the fate of PBN-adducts and their impact on lipid oxidation mechanisms in mayonnaise were investigated. The main signals detected by Electron Spin Resonance (ESR) were attributed to L-radicals attached to 2-methyl-2-nitrosopropane (MNP), one of three degradation products of the PBN-peroxy-adduct. The second degradation product, benzaldehyde, was detected with Nuclear Magnetic Resonance (H NMR), in line with MNP-L adduct generation. For the third class of degradation products, LO-radicals, their scission products were detected with H NMR and indicated that LO-radicals have a major impact on downstream oxidation pathways. This precludes mechanistical studies in presence of PBN. Degradation products of PBN-adducts can, however, be used for early assessment of antioxidants efficacy in oil-in-water emulsions.

摘要

蛋黄酱的质量恶化是由自由基反应介导的脂质氧化引起的。自由基的评估可以实现早期脂质氧化评估，并提供机制见解。为了监测短寿命的脂质自由基，常用自旋捕获剂 N-叔丁基-α-苯基硝酮（PBN）。在这项研究中，研究了 PBN 加合物的命运及其对蛋黄酱中脂质氧化机制的影响。电子自旋共振（ESR）检测到的主要信号归因于与 2-甲基-2-亚硝基丙烷（MNP）相连的 L-自由基，MNP 是 PBN-过氧加合物的三种降解产物之一。第二种降解产物苯甲醛通过核磁共振（H NMR）检测到，与 MNP-L 加合物的生成一致。对于第三类降解产物 LO-自由基，用 H NMR 检测到它们的断裂产物，表明 LO-自由基对下游氧化途径有重大影响。这使得在存在 PBN 的情况下无法进行机械研究。然而，PBN 加合物的降解产物可用于早期评估水包油乳液中抗氧化剂的功效。