Brudzynski Katrina
Department of Drug Discovery, Bee-Biomedicals Inc., St. Catharines, ON L2T 3T4, Canada.
Department of Biological Sciences, Formerly, Brock University, St. Catharines, ON L2S 3A1, Canada.
Metabolites. 2023 Apr 6;13(4):526. doi: 10.3390/metabo13040526.
Hydrogen peroxide is the principal antibacterial compound of honey and its concentration determines honey bacteriostatic (MIC) and bactericidal (MBC) potencies. Levels of HO produced are highly relevant to honey therapeutic potential, but they vary extensively among honey with reasons not immediately apparent. According to a traditional view, HO is produced as a by-product of glucose oxidation by the honey bee enzyme, glucose oxidase; however, significant levels of HO could be produced in a non-enzymatic way via polyphenol autooxidation. The aim of this study was to evaluate the potential for such an alternative pathway by re-examining evidence from many experimental and correlative studies in order to identify factors and compounds required for pro-oxidant activity. Unexpectedly, the color intensity was found to be the main indicator separating honey varieties based on the quantitative differences in the polyphenolic content, antioxidant activity and the content of transition metals, Fe, Cu and Mn, the main factors required for pro-oxidant effects. The color-impeding polyphenolics and their oxidation products (semiquinones and quinones) further contributed to color development through multiple chemical conjugations with proteins, phenolic oxidative polymerization, chelation or the reduction of metal ions. Moreover, quinones, as an intrinsic part of polyphenol redox activity, play an active role in the formation of higher-order structures, melanoidins and colloids in honey. The latter structures are also known to chelate metal ions, potentially contributing to HO production. Thus, the color intensity appears as a major parameter that integrates polyphenol-dependent pro-oxidant reactions resulting in HO generation.
过氧化氢是蜂蜜中的主要抗菌化合物，其浓度决定了蜂蜜的抑菌（MIC）和杀菌（MBC）能力。所产生的过氧化氢水平与蜂蜜的治疗潜力高度相关，但不同蜂蜜之间的过氧化氢水平差异很大，原因尚不明确。根据传统观点，过氧化氢是蜜蜂体内葡萄糖氧化酶催化葡萄糖氧化的副产物；然而，多酚的自动氧化也可以非酶促方式产生大量的过氧化氢。本研究的目的是通过重新审视众多实验和相关研究的证据，评估这种替代途径的可能性，以确定促氧化活性所需的因素和化合物。出乎意料的是，基于多酚含量、抗氧化活性以及过渡金属铁、铜和锰（促氧化作用的主要因素）的定量差异，颜色强度被发现是区分蜂蜜品种的主要指标。阻碍颜色的多酚及其氧化产物（半醌和醌）通过与蛋白质的多种化学共轭、酚类氧化聚合、螯合或金属离子还原进一步促进了颜色的形成。此外，醌作为多酚氧化还原活性的固有组成部分，在蜂蜜中高阶结构、类黑素和胶体的形成中发挥着积极作用。后一种结构也已知能螯合金属离子，可能有助于过氧化氢的产生。因此，颜色强度似乎是一个主要参数，它整合了依赖多酚的促氧化反应，从而导致过氧化氢的产生。
