Poli J-P, Guinoiseau E, Luciani A, Yang Y, Battesti M-J, Paolini J, Costa J, Quilichini Y, Berti L, Lorenzi V
Laboratoire de Biochimie et de Biologie Moléculaire du végétal, UMR CNRS 6134, Université de Corse, Corte, France.
Laboratoire de Chimie des Produits Naturels UMR CNRS 6134, Université de Corse, Corte, France.
Lett Appl Microbiol. 2018 May;66(5):427-433. doi: 10.1111/lam.12868. Epub 2018 Mar 24.
In honeys, several molecules have been known for their antibacterial or wound healing properties. Corsican honeys just began to be tested for their antimicrobial activity with promising results on Pseudomonas aeruginosa. So, identification of active molecules and their mode of action was determined. Hydrogen peroxide concentrations were evaluated and, in parallel, the minimal inhibitory concentrations (MIC) values were performed with and without catalase. More, the quantity of phenolic compounds and ORAC assay were measured. Observation of antibacterial action was done using scanning electron microscopy (SEM) followed by plasmidic DNA extraction. MIC values of chestnut grove and honeydew maquis honeys vary between 7 and 8%, showing a strong antimicrobial capacity, associated with a plasmidic DNA degradation. When catalase is added, MIC values significatively increase (25%) without damaging DNA, proving the importance of H O . This hypothesis is confirmed by SEM micrographies which did not show any morphological damages but a depletion in bacterial population. Although, such low concentrations of H O (between 23 μmol l and 54 μmol l ) cannot explain antimicrobial activity and might be correlated with phenolic compounds concentration. Thus, Corsican honeys seem to induce DNA damage when H O and phenolic compounds act in synergy by a putative pro-oxidant effect.
We started to determine the antibacterial efficiency of Corsican chestnut grove and honeydew maquis honeys on Pseudomonas aeruginosa. No morphological alteration of the bacterial surface was observed. Antimicrobial action seems to be related to the synergy between hydrogen peroxide and phenolic compounds. The exerted pro-oxidant activity leads to a degradation of P. aeruginosa plasmidic DNA. This is the first study that investigate the primary antibacterial mechanism of Corsican honeys.
在蜂蜜中，有几种分子因其抗菌或伤口愈合特性而为人所知。科西嘉蜂蜜刚刚开始接受抗菌活性测试，对铜绿假单胞菌显示出有前景的结果。因此，确定了活性分子及其作用方式。评估了过氧化氢浓度，同时，在有和没有过氧化氢酶的情况下进行了最低抑菌浓度（MIC）值测定。此外，还测量了酚类化合物的含量和氧自由基吸收能力（ORAC）测定。使用扫描电子显微镜（SEM）观察抗菌作用，随后进行质粒DNA提取。栗树林蜂蜜和蜜露灌丛林蜂蜜的MIC值在7%至8%之间变化，显示出很强的抗菌能力，与质粒DNA降解有关。当加入过氧化氢酶时，MIC值显著增加（25%），但不会损害DNA，证明了过氧化氢的重要性。SEM显微照片证实了这一假设，照片未显示任何形态损伤，但细菌数量减少。尽管如此，如此低浓度的过氧化氢（23μmol/L至54μmol/L之间）无法解释抗菌活性，可能与酚类化合物浓度相关。因此，当过氧化氢和酚类化合物通过假定的促氧化作用协同作用时，科西嘉蜂蜜似乎会诱导DNA损伤。
我们开始确定科西嘉栗树林蜂蜜和蜜露灌丛林蜂蜜对铜绿假单胞菌的抗菌效率。未观察到细菌表面的形态改变。抗菌作用似乎与过氧化氢和酚类化合物之间的协同作用有关。所发挥的促氧化活性导致铜绿假单胞菌质粒DNA降解。这是第一项研究科西嘉蜂蜜主要抗菌机制的研究。
