02560naa a2200277 a 450000100080000000500110000800800410001902400520006010000210011224501530013326000090028652016540029565300350194965300150198465300310199965300220203065300170205270000200206970000230208970000200211270000190213270000200215170000160217170000170218777300780220421107562019-11-19 2019 bl uuuu u00u1 u #d7 ahttps://doi.org/10.1016/j.jaap.2019.1046342DOI1 aAQUINO, A. M. de aEvaluation of molecular properties of humic acids from vermicompost by 13 C CPMAS NMR spectroscopy and thermochemolysis GC MSh[electronic resource] c2019 aThe molecular characteristics of different vermicomposts, produced with variable rates of cattle manure and cotton residues, and of related humic acids were determined by 13C-CPMAS NMR and Off-line pyrolysis THM-GC?MS. The analyses highlighted a composition of mature vermicomposts based on differential amounts of lignocellulosic fraction and alkyl compounds inherited from original biomasses, thus revealing a decrease of overall hydrophobic character at increasing amounts of cotton input. The evaluation of molecular parameters derived from both solid state NMR spectra and from the specific biomarkers released by thermochemolysis suggested that the humification process was mainly characterized by the selective preservation of specific lignin derivatives. The potential bioactive properties of humic acids were hence evaluated in a bioassays test on maize seedlings. The humic extracts showed a differential response in root growth-promoting effect, depending on the specific molecular features. The higher bioactivity found in humic components isolated from vermicompost with no or low addition of cotton residues, supported the role of the overall hydrophobic character and of the large content of bioavailable lignin units and nitrogen moieties. These results confirm that the combination of solid state NMR and thermochemolysis are valuable and efficient tools to assess the molecular quality of natural organic matter. The detailed molecular characterization of compost materials may hence represent a useful requirement to select the most suitable application of bulk biomasses and derived fractions for soil organic matter managements. aCotton residues Humic extracts aCow manure aMolecular characterization aStructura ctivity aVermicompost1 aCANELLAS, L. P.1 aSILVA, A. P. S. da1 aCANELLAS, N. O.1 aLIMA, L. da S.1 aOLIVARES, F. L.1 aPICCOLO, A.1 aSPACCINI, R. tJournal of Analytical and Applied Pyrolysis, v .141, 104634, August 2019.