The potential of marine dissolved organic matter (DOM) for free radical scavenging has been extensively evaluated, however, the quantitative assessment of the antioxidant potential has been recently measured for the first time. The linkage of the DOM antioxidant potential to its molecular composition has not yet been examined. Following this line, this article takes a step forward by assessing, throughout a polarity-mediated fractionation, (1) the antioxidant capacity and phenolic content and (2) the molecular characterization of DOM in a more exhaustive manner. (3) The DOM antioxidant potential and phenolic content was linked to the molecular composition of DOM, which was molecularly characterized using ultrahigh resolution Fourier transform Ion Cyclotron Resonance mass spectrometry (FT-ICR MS). Antioxidant activity and phenolic content were quantified by the free radical 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS⋅) and the Folin-Ciocalteu methods, respectively. We considered three types of different natural DOM samples: the deep North Pacific Ocean, the oligotrophic surface of the North Pacific Ocean and porewater from the sulfidic tidal flats of the Wadden Sea. Bulk porewater and its individual polarity fractions presented the highest antioxidant activity and phenolic content. DOM from the water column samples had lower antioxidant activity and phenolic content than porewater, but exceeded what it is commonly found in macroalgae, microalgae, fruits and vegetables with cosmeceutical purposes. Our values were similar to published values for terrestrial DOM. The variations in bioactivity were dependent on polarity and molecular composition. The high resolution and high mass accuracy used to determine the molecular composition of marine DOM and the chemometric and multistatistical analyses employed have allowed to distinguish molecular categories that are related to the bioactive potential. As a future perspective, we performed cytotoxicity tests with human cells and propose marine DOM as a natural ingredient for the development of cosmeceutical products.

中文翻译：

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海洋溶解有机物的抗氧化活性和酚类含量及其与分子组成的关系

海洋溶解有机物 (DOM) 清除自由基的潜力已得到广泛评估，然而，最近首次测量了抗氧化潜力的定量评估。DOM 抗氧化潜力与其分子组成之间的联系尚未得到研究。沿着这条路线，本文向前迈进了一步，在整个极性介导的分馏过程中，(1) 抗氧化能力和酚类含量以及 (2) 以更详尽的方式评估 DOM 的分子特征。(3) DOM 的抗氧化潜力和酚类含量与 DOM 的分子组成有关，使用超高分辨率傅里叶变换离子回旋共振质谱 (FT-ICR MS) 对其进行分子表征。抗氧化活性和酚类含量分别通过自由基 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS⋅) 和 Folin-Ciocalteu 方法进行量化。我们考虑了三种不同的天然 DOM 样本：北太平洋深部、北太平洋的贫营养表面和来自瓦登海硫化物潮滩的孔隙水。大量孔隙水及其各个极性部分表现出最高的抗氧化活性和酚类含量。水柱样品中的 DOM 的抗氧化活性和酚类含量低于孔隙水，但超过了大型藻类、微藻类、药用水果和蔬菜中常见的含量。我们的值类似于已发布的陆地 DOM 值。生物活性的变化取决于极性和分子组成。用于确定海洋 DOM 分子组成的高分辨率和高质量准确度以及所采用的化学计量学和多统计分析允许区分与生物活性潜力相关的分子类别。从未来的角度来看，我们对人体细胞进行了细胞毒性测试，并建议将海洋 DOM 作为开发药妆产品的天然成分。