Unraveling a mechanism of honey antibacterial action: Polyphenol/H2O2-induced oxidative effect on bacterial cell growth and on DNA degradation
Unraveling a mechanism of honey antibacterial action: Polyphenol/H2O2-induced oxidative effect on bacterial cell growth and on DNA degradation
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DOI：
10.1016/j.foodchem.2012.01.035
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发表时间：
2012-07-15
期刊：
影响因子：
8.8
通讯作者：
Miotto, Danielle
中科院分区：
文献类型：
--
作者：
Brudzynski, Katrina;Abubaker, Kamal;Miotto, Danielle
在蜂蜜中发现了几种具有抗菌活性的化合物，然而，它们导致细菌生长抑制和细菌死亡的机制仍然未知。我们最近发现蜂蜜具有由蜂蜜过氧化氢和未知蜂蜜成分介导的DNA降解活性。在这里，我们提供了证据，活性蜂蜜（MIC 90为6.25- 12.5%v/v）具有显着更高的酚类化合物（p < 0.02），更高的自由基清除活性（p < 0.005）比平均活性的蜂蜜。过氧化氢酶去除过氧化氢消除酚类和过氧化氢引起的抑菌活性，这表明这些化合物之间的耦合化学导致的生长抑制。酚类物质和过氧化氢都参与了蜂蜜对DNA的降解。单独用H2 O2处理质粒DNA不影响DNA的完整性，但过氧化氢酶从蜂蜜中去除H2 O2防止DNA降解。从蜂蜜中提取的多酚降解质粒DNA中存在的H2 O2和Cu（II）的芬顿型反应。DNA降解的程度呈负相关的多酚浓度在这个系统中，以及蜂蜜。在低含量时，蜂蜜多酚具有损伤DNA的促氧化活性。总之，具有促氧化活性的蜂蜜酚类物质是赋予H2 O2氧化作用的必要中间体。苯酚/H2 O2诱导的氧化应激是蜂蜜抑菌和DNA损伤活性的机制。皇冠版权所有（C）2012由爱思唯尔有限公司出版。保留所有权利。
Several compounds with antibacterial activities were identified in honey however, a mechanism by which they lead to bacterial growth inhibition and bacterial death remains still unknown. We recently found that honeys possess DNA degrading activity mediated by honey hydrogen peroxide and an unknown honey component(s). Here we provide evidence that active honeys (MIC90 of 6.25-12.5% v/v) possessed significantly higher levels of phenolics (p < 0.02) of higher radical scavenging activities (p < 0.005) than honeys of average activity. Removal of H2O2 by catalase eliminated bacteriostatic activities caused by both phenolics and H2O2 suggesting that the growth inhibition resulted from the coupling chemistry between these compounds. Both phenolics and H2O2 were involved in DNA degradation by honeys. Treatment of plasmid DNA with H2O2 alone did not affect the DNA integrity but H2O2 removal from honey by catalase prevented DNA degradation. Polyphenols extracted from honeys degraded plasmid DNA in the presence of H2O2 and Cu(II) in the Fenton-type reaction. The extent of DNA degradation was inversely related to the polyphenol concentration in this system as well as in honeys. At low content, honey polyphenols exerted pro-oxidant activity damaging to DNA. In conclusion, honey phenolics with pro-oxidant activities were necessary intermediates that conferred oxidative action of H2O2. Phenolic/H2O2-induced oxidative stress constituted the mechanism of honey bacteriostatic and DNA damaging activities. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.