Centre for Environmental Research, Sustainability and Innovation, Department of Environmental Science, School of Science, Institute of Technology Sligo, Ash Ln, Ballytivnan, F91 YW50 Sligo, Ireland.
Marine Biodiversity, School of Chemistry, Ryan Institute, National University of Ireland Galway (NUI Galway), University Road, H91 TK33 Galway, Ireland.
Int J Mol Sci. 2021 Nov 11;22(22):12196. doi: 10.3390/ijms222212196.
Microalgae have received growing interest for their capacity to produce bioactive metabolites. This study aimed at characterising the antimicrobial potential of the marine dinoflagellate strain LACW11, isolated from the west of Ireland. Amphidinolides have been identified as cytotoxic polyoxygenated polyketides produced by several species. Phylogenetic inference assigned our strain to subclade III, along with isolates interspersed in different geographic regions. A two-stage extraction and fractionation process of the biomass was carried out. Extracts obtained after stage-1 were tested for bioactivity against bacterial ATCC strains of , , and . The stage-2 solid phase extraction provided 16 fractions, which were tested against and Fractions I, J and K yielded minimum inhibitory concentrations between 16 μg/mL and 256 μg/mL for both Gram-positive. A targeted metabolomic approach using UHPLC-HRMS/MS analysis applied on fractions G to J evidenced the presence of amphidinol type compounds AM-A, AM-B, AM-22 and a new derivative dehydroAM-A, with characteristic masses of 1361, 1463, 1667 and 1343, respectively. Combining the results of the biological assays with the targeted metabolomic approach, we could conclude that AM-A and the new derivative dehydroAM-A are responsible for the detected antimicrobial bioactivity.
微藻因其产生生物活性代谢物的能力而受到越来越多的关注。本研究旨在表征从爱尔兰西部分离的海洋甲藻菌株 LACW11 的抗菌潜力。 Amphidinolides 已被鉴定为几种产生细胞毒性的多氧化多酮，由不同物种产生。系统发育推断将我们的菌株与分布在不同地理区域的分离株一起分配到亚群 III。对生物量进行了两阶段提取和分级过程。在第 1 阶段之后获得的提取物用于测试对细菌 ATCC 菌株 的生物活性。第 2 阶段固相萃取提供了 16 个馏分，这些馏分针对 和 进行了测试。馏分 I、J 和 K 对革兰氏阳性菌的最小抑菌浓度在 16 μg/mL 和 256 μg/mL 之间。使用 UHPLC-HRMS/MS 分析对馏分 G 到 J 进行的靶向代谢组学方法表明存在 Amphidinol 型化合物 AM-A、AM-B、AM-22 和新衍生物去氢 AM-A，其特征质量分别为 1361、1463、1667 和 1343。将生物测定结果与靶向代谢组学方法相结合，我们可以得出结论，AM-A 和新的衍生物去氢 AM-A 是检测到的抗菌生物活性的原因。
