Dataset Information

Cellulose Structural Changes during Mild Torrefaction of Eucalyptus Wood.

ABSTRACT: The changes in the cellulose structure of eight Eucalyptus species (E. botryoides, E. globulus, E. grandis, E. maculata, E. propinqua, E. rudis, E. saligna and E. viminalis) in a mild torrefaction (from 160 °C to 230 °C, 3 h) were studied in situ and after cellulose isolation from the wood by solid-state carbon nuclear magnetic resonance (¹³C NMR), wide angle X-ray scattering (WAXS), Fourier transform infrared spectroscopy (FTIR) and by analytic pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS). Changes in molecular weight were assessed by viscosimetry. A small decrease in cellulose crystallinity (ca. 2%-3%) was attributed to its amorphization on crystallite surfaces as a result of acid hydrolysis and free radical reactions resulting in the homolytic splitting of glycosidic bonds. The degree of the cellulose polymerization (DPv) decreased more than twice during the heat treatment of wood. It has been proposed that changes in the supramolecular structure of cellulose and in molecular weight during a heat treatment can be affected by the amount of lignin present in the wood. The limitations of FTIR and Py-GC/MS techniques to distinguish the minor changes in cellulose crystallinity were discussed.

SUBMITTER: Lourenco A

PROVIDER: S-EPMC7760041 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Cellulose Structural Changes during Mild Torrefaction of Eucalyptus Wood.

Lourenço Ana A Araújo Solange S Gominho Jorge J Evtuguin Dmitry D

Polymers 20201128 12

The changes in the cellulose structure of eight Eucalyptus species (E. botryoides, E. globulus, E. grandis, E. maculata, E. propinqua, E. rudis, E. saligna and E. viminalis) in a mild torrefaction (from 160 °C to 230 °C, 3 h) were studied in situ and after cellulose isolation from the wood by solid-state carbon nuclear magnetic resonance (13C NMR), wide angle X-ray scattering (WAXS), Fourier transform infrared spectroscopy ...[more]

PMID: 33260756

Similar Datasets

Project description:BACKGROUND: Renowned for their fast growth, valuable wood properties and wide adaptability, Eucalyptus species are amongst the most planted hardwoods in the world, yet they are still at the early stages of domestication because conventional breeding is slow and costly. Thus, there is huge potential for marker-assisted breeding programs to improve traits such as wood properties. To this end, the sequencing, analysis and annotation of a large collection of expressed sequences tags (ESTs) from genes involved in wood formation in Eucalyptus would provide a valuable resource. RESULTS: We report here the normalization and sequencing of a cDNA library from developing Eucalyptus secondary xylem, as well as the construction and sequencing of two subtractive libraries (juvenile versus mature wood and vice versa). A total of 9,222 high quality sequences were collected from about 10,000 cDNA clones. The EST assembly generated a set of 3,857 wood-related unigenes including 2,461 contigs (Cg) and 1,396 singletons (Sg) that we named 'EUCAWOOD'. About 65% of the EUCAWOOD sequences produced matches with poplar, grapevine, Arabidopsis and rice protein sequence databases. BlastX searches of the Uniref100 protein database allowed us to allocate gene ontology (GO) and protein family terms to the EUCAWOOD unigenes. This annotation of the EUCAWOOD set revealed key functional categories involved in xylogenesis. For instance, 422 sequences matched various gene families involved in biosynthesis and assembly of primary and secondary cell walls. Interestingly, 141 sequences were annotated as transcription factors, some of them being orthologs of regulators known to be involved in xylogenesis. The EUCAWOOD dataset was also mined for genomic simple sequence repeat markers, yielding a total of 639 putative microsatellites. Finally, a publicly accessible database was created, supporting multiple queries on the EUCAWOOD dataset. CONCLUSION: In this work, we have identified a large set of wood-related Eucalyptus unigenes called EUCAWOOD, thus creating a valuable resource for functional genomics studies of wood formation and molecular breeding in this economically important genus. This set of publicly available annotated sequences will be instrumental for candidate gene approaches, custom array development and marker-assisted selection programs aimed at improving and modulating wood properties.

Dataset Information

Cellulose Structural Changes during Mild Torrefaction of Eucalyptus Wood.

Publications

Cellulose Structural Changes during Mild Torrefaction of <i>Eucalyptus</i> Wood.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets