Abstract

The antibacterial activity of methanolic extracts of eight Mediterranean brown algae belonging to the genera Cystoseira sensu lato, Dictyopteris and Padina was investigated. Extracts from Sargassaceae showed antibacterial activity. Specifically, Carpodesmia crinita and Carpodesmia brachycarpa extracts inhibited the growth of the Gram-positive strain Kocuria rhizophila whereas Cystoseira compressa and Carpodesmia amentacea extracts showed antibacterial activity against the Gram-positive strains, Kocuria rhizophila and Staphylococcus aureus. None of them inhibited the growth of the Gram-negative bacterium Escherichia coli. The extracts of Cystoseira sp. pl. and Treptacantha ballesterosii did not show any antibacterial activity. HPLC-MS analysis of the extracts allowed identification of polar compounds. Taxa of the genus Cystoseira sensu lato showed a higher number of compounds than Dictyopteris polypodioides and Padina pavonica. Some differences found among and within taxa can be attributed to the different depths where these algae live, to thallus morphology and herbivore pressure. Particularly interesting were the phenol compounds, which showed differences among the genera but also within the genus Cystoseira sensu lato. Noteworthy, the almost exclusive presence of the fukiik acid isomer and of bromo-phloroglucinol in Carpodesmia amentacea, and the presence of exifone, able to bind iron metal ions, in Carpodesmia amentacea, Cystoseira compressa and Treptacantha ballesterosii.

摘要

研究了属于Cystoseira sensu lato、Dictyopteris和Padina属的八种地中海褐藻的甲醇提取物的抗菌活性。马尾藻科的提取物显示出抗菌活性。具体而言，Carpodesmia crinita和Carpodesmia brachycarpa提取物抑制革兰氏阳性菌株Kocuria rhizophila的生长，而Cystoseira compressa和Carpodesmia amentacea提取物显示出对革兰氏阳性菌株Kocuria rhizophila和金黄色葡萄球菌的抗菌活性. 它们都没有抑制革兰氏阴性细菌大肠杆菌的生长。Cystoseira sp的提取物。pl。和Treptacantha ballesterosii没有显示出任何抗菌活性。提取物的 HPLC-MS 分析允许鉴定极性化合物。Cystoseira sensu lato属的分类群显示出比Dictyopteris polypodioides和Padina pavonica更多的化合物。在分类群之间和内部发现的一些差异可归因于这些藻类生活的不同深度、菌体形态和食草动物压力。特别有趣的是酚类化合物，它表现出属之间以及属内的差异感觉囊孢子虫。值得注意的是，在 Carpodesmia mentacea 中几乎独家存在 fukiik 酸异构体和溴间苯三酚，在Carpodesmia mentacea、Cystoseira compressa和Treptacantha ballesterosii中存在能够结合铁金属离子的exifone 。