Moilanen Johanna, Karonen Maarit, Tähtinen Petri, Jacquet Rémi, Quideau Stéphane, Salminen Juha-Pekka
Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, FI-20014 Turku, Finland.
Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, FI-20014 Turku, Finland.
Phytochemistry. 2016 May;125:65-72. doi: 10.1016/j.phytochem.2016.02.008. Epub 2016 Feb 18.
Ellagitannins are a subclass of hydrolysable tannins that have been suggested to function as defensive compounds of plants against herbivores. However, it is known that the conditions in the digestive tracts of different herbivores are variable, so it seems reasonable to anticipate that the reactivities and modes of actions of these ingested defensive compounds would also be different. A previous study on a few ellagitannins has shown that these polyphenolic compounds are highly oxidizable at high pH and that their bioactivity can be attributed to certain structural features. Herein, the activities of 13 ellagitannins using the deoxyribose assay were measured. The results provided information about the anti-oxidant, pro-oxidant and metal chelating properties of ellagitannins. Surprisingly, many of the tested ellagitannins exhibited pro-oxidant activities even at neutral pH and only moderate to low radical scavenging activities, although the metal chelating capacities of all tested ellagitannins were relatively high.
鞣花单宁是可水解单宁的一个亚类，有人认为它是植物抵御食草动物的防御性化合物。然而，众所周知，不同食草动物消化道内的条件各不相同，因此可以合理推测，这些摄入的防御性化合物的反应活性和作用方式也会有所不同。先前对几种鞣花单宁的研究表明，这些多酚类化合物在高pH值下具有高度氧化性，其生物活性可归因于某些结构特征。在此，使用脱氧核糖分析法测定了13种鞣花单宁的活性。结果提供了有关鞣花单宁的抗氧化、促氧化和金属螯合特性的信息。令人惊讶的是，许多受试鞣花单宁即使在中性pH值下也表现出促氧化活性，而自由基清除活性仅为中度至低度，尽管所有受试鞣花单宁的金属螯合能力相对较高。
