气候变化领域集成服务门户(CCPortal): Sargassum sp. Act as a Large Regional Source of Marine Dissolved Organic Carbon and Polyphenols

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DOI	10.1029/2019GB006225
	Sargassum sp. Act as a Large Regional Source of Marine Dissolved Organic Carbon and Polyphenols
	Powers L.C.; Hertkorn N.; McDonald N.; Schmitt-Kopplin P.; Del Vecchio R.; Blough N.V.; Gonsior M.
发表日期	2019
ISSN	0886-6236
EISSN	1944-9224
起始页码	1423
结束页码	1439
卷号	33 期号:11
英文摘要	Dissolved organic carbon (DOC) plays critical roles in marine carbon cycling, but its sources and sinks remain uncertain. In this study, we monitored DOC exudation rates of Sargassum natans under visible light (λ > 390 nm) and solar radiation. DOC release rates ranged from 7 to 10 μg C g−1 biomass hr−1 (wet weight) under visible light, but increased to 23 to 41 μg C g−1 biomass hr−1 when exposed to natural sunlight. Results indicate that DOC released by Sargassum could amount to 0.3 to 1.2 Tg C/year, potentially contributing significantly to the marine DOC pool in the Gulf of Mexico and Western North Atlantic. We employed the Folin-Ciocalteu phenolic content method, nuclear magnetic resonance (NMR) spectroscopy, and ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize the diverse pool of organic compounds exuded from Sargassum. Results from these complementary methods showed that Sargassum release large quantities of phlorotannins, a class of polyphenols that have very similar properties to terrestrial DOC. These phlorotannins and their oxygenated phenolic derivatives exhibit a high hydrogen deficiency and functionalization (i.e., 4 to 6 oxygen atoms per aromatic ring), representing 5 to 18% of the released DOC isolated by solid phase extraction. Thus, Sargassum is the largest biological source of open ocean polyphenols recorded to date. The amount of polyphenolic DOC released by Sargassum challenges previous beliefs that all polyphenols found within the oceans are remnants of terrestrial organic matter, although the stability of phlorotannins and their derivatives needs to be further evaluated. © 2019. American Geophysical Union. All Rights Reserved.
英文关键词	DOC; FT-ICR MS; marine dissolved organic matter; marine polyphenols; NMR; Sargassum
语种	英语
scopus关键词	biochemical composition; brown alga; dissolved organic carbon; FTIR spectroscopy; marine ecosystem; mass spectrometry; nuclear magnetic resonance; phenolic compound; seawater; Sargassum; Sargassum natans; Sargassum sp.
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129696
作者单位	University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, Solomons, MD, United States; Helmholtz Zentrum Muenchen–German Research Center for Environmental Health, Research Unit Analytical BioGeoChemistry, Neuherberg, Germany; Bermuda Institute of Ocean Sciences, St. George's, Bermuda; GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany; Chair of Analytical Food Chemistry, Technische Universität München, Weihenstephan, Germany; Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States; Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, United States
推荐引用方式 GB/T 7714	Powers L.C.,Hertkorn N.,McDonald N.,et al. Sargassum sp. Act as a Large Regional Source of Marine Dissolved Organic Carbon and Polyphenols[J],2019,33(11).
APA	Powers L.C..,Hertkorn N..,McDonald N..,Schmitt-Kopplin P..,Del Vecchio R..,...&Gonsior M..(2019).Sargassum sp. Act as a Large Regional Source of Marine Dissolved Organic Carbon and Polyphenols.Global Biogeochemical Cycles,33(11).
MLA	Powers L.C.,et al."Sargassum sp. Act as a Large Regional Source of Marine Dissolved Organic Carbon and Polyphenols".Global Biogeochemical Cycles 33.11(2019).