Molecular characterization of an end-residue of humeomics applied to a soil humic acid

被引:26
作者
Nebbioso, A. [1 ]
Piccolo, A. [1 ]
Lamshoeft, M. [2 ]
Spiteller, M. [2 ]
机构
[1] Univ Naples Federico II, Ctr Interdipartimentale Ric Spettroscopia Risonan, Portici, Italy
[2] Dortmund Tech Univ, Inst Umweltforsch, D-44227 Dortmund, Germany
来源
RSC ADVANCES | 2014年 / 4卷 / 45期
关键词
DISSOLVED ORGANIC-MATTER; PERMANGANATE OXIDATION; NMR-SPECTROSCOPY; SUBSTANCES; FRACTIONATION; SCIENCE;
D O I
10.1039/c4ra01619j
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Humeomics encompasses step-wise chemical fractionation and instrumental determination to fully characterize the heterogeneous molecular composition of natural organic matter. Humeomics applied to a terrestrial humic acid produced a recalcitrant end-residue, that was solubilized in alkali and size-fractionated by preparative high performance size exclusion chromatography (HPSEC). The ten separated size-fractions were then subjected to analytical HPSEC hyphenated with a high-resolution electrospray mass spectrometer (ESI-MS). Total ion chromatograms of size-fractions showed two eluting peaks, the molecular masses of which were identified with empirical formulae by ESI-MS. Most empirical formulae were easily associated with linear alkanoic, unsaturated, hydroxylated and hydroxy-unsaturated acids, as well as cyclic acids, but some compound structures were unclear. Tandem MS fragmentation was applied to one linear and three cyclic compounds, to elucidate their structures as hydroxyunsaturated hexanoic acid, two furane rings and a norbornane-like ring, respectively. The latter three compounds were never reported for terrestrial humic acid, but they resembled the carboxyl-rich alicyclic molecules, which had been proposed previously for dissolved organic matter. Quantitative measurement of components indicated that long-chain saturated acids were present in large-sized fractions more than in short-chain homologues, whereas unsaturated, hydroxylated and most cyclic acids were more abundant in small-sized fractions. This suggests that long, saturated and unsubstituted linear acids allow formation of large suprastructures, probably as a result of favorable intermolecular packing, compared with the irregularly shaped cyclic, unsaturated or hydroxylated compounds. We showed that humeomics clarifies the molecular composition and conformational arrangement of natural organic matter, and may help to elucidate the relationship between humic structure and environmental activity.
引用
收藏
页码:23658 / 23665
页数:8
相关论文
共 18 条
[1]   Advanced CPMAS-13C NMR techniques for molecular characterization of size-separated fractions from a soil humic acid [J].
Conte, Pellegrino ;
Spaccini, Riccardo ;
Piccolo, Alessandro .
ANALYTICAL AND BIOANALYTICAL CHEMISTRY, 2006, 386 (02) :382-390
[2]   CHARACTERIZATION OF THE DISSOCIATION BEHAVIOR OF GAS-PHASE PROTONATED AND METHYLATED LACTONES [J].
DONOVAN, T ;
BRODBELT, J .
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY, 1992, 3 (01) :47-59
[3]   Characterization of a major refractory component of marine dissolved organic matter [J].
Hertkorn, N ;
Benner, R ;
Frommberger, M ;
Schmitt-Kopplin, P ;
Witt, M ;
Kaiser, K ;
Kettrup, A ;
Hedges, JI .
GEOCHIMICA ET COSMOCHIMICA ACTA, 2006, 70 (12) :2990-3010
[4]   High-field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter [J].
Hertkorn, N. ;
Harir, M. ;
Koch, B. P. ;
Michalke, B. ;
Schmitt-Kopplin, P. .
BIOGEOSCIENCES, 2013, 10 (03) :1583-1624
[5]   PERMANGANATE OXIDATION OF HUMIC ACIDS EXTRACTED FROM ACID SOILS [J].
MATSUDA, K ;
SCHNITZER, M .
SOIL SCIENCE, 1972, 114 (03) :185-+
[6]   PERMANGANATE OXIDATION OF HUMIC ACIDS [J].
MAXIMOV, OB ;
SHVETS, TV ;
ELKIN, YN .
GEODERMA, 1977, 19 (01) :63-78
[7]   Composition of dissolved organic matter within a lacustrine environment [J].
McCaul, Margaret V. ;
Sutton, David ;
Simpson, Andre J. ;
Spence, Adrian ;
McNally, David J. ;
Moran, Brian W. ;
Goel, Alok ;
O'Connor, Brendan ;
Hart, Kris ;
Kelleher, Brian P. .
ENVIRONMENTAL CHEMISTRY, 2011, 8 (02) :146-154
[8]   Physiological effects of humic substances on higher plants [J].
Nardi, S ;
Pizzeghello, D ;
Muscolo, A ;
Vianello, A .
SOIL BIOLOGY & BIOCHEMISTRY, 2002, 34 (11) :1527-1536
[9]  
Nebbioso A., 2014, SOIL BIOL BIOCH
[10]   Advances in humeomics: Enhanced structural identification of humic molecules after size fractionation of a soil humic acid [J].
Nebbioso, Antonio ;
Piccolo, Alessandro .
ANALYTICA CHIMICA ACTA, 2012, 720 :77-90