Hemicelluloses were extracted from a softwood acid sulfite pulp in a three-step procedure. Further delignification step resulted in a holocellulose pulp containing only 1.7 wt.% of the lignin left. Cold caustic extraction (CCE) with 18 wt.% NaOH at 60 °C for 1 h was performed to solubilize hemicelluloses of the holocellulose. An unbleached cellulose pulp was then obtained 97% pure, which indicates that 89% of the hemicelluloses were removed. After purification, extraction yields between 1.1 wt.% and 9.5 wt.% were obtained from the delignified pulp and the hemicelluloses' chemical compositions and structures were investigated by H, C nuclear magnetic resonance spectroscopy (NMR) and two-dimensional NMR by correlation spectroscopy (2D-COSY) and proton-detected heteronuclear single-quantum correlation (2D-HSQC), high-performance anion-exchange chromatography coupled with a pulsed amperometry detector (HPAEC-PAD), size-exclusion chromatography coupled with a refractive index detector (SEC-RI) and thermogravimetric analyses (TGA). Hemicelluloses were obtained with a purity of 96%, with short cellulosic chains as the only residue. Sulfite pulping modified the hemicelluloses' structure, and it was found that two types of hemicelluloses were isolated, glucomannans, predominant at 67%, and methylglucuronoxylans. Finally, alkali-soluble hemicelluloses displayed relatively narrow size distributions and low molar masses, M varying between 18,900 and 30,000 g/mol after acid sulfite pulping.
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http://dx.doi.org/10.3390/polym13132044 | DOI Listing |
PLoS One
January 2025
Faculty of Biology, VNU University of Science, Vietnam National University, Hanoi, Vietnam.
The autonomous and active Long-Interspersed Element-1 (LINE-1, L1) and the non-autonomous Alu retrotransposon elements, contributing to 30% of the human genome, are the most abundant repeated sequences. With more than 90% of their sequences being methylated in normal cells, these elements undeniably contribute to the global DNA methylation level and constitute a major part of circulating-cell-free DNA (cfDNA). So far, the hypomethylation status of LINE-1 and Alu in cellular and extracellular DNA has long been considered a prevailing hallmark of ageing-related diseases and cancer.
View Article and Find Full Text PDFPLoS One
January 2025
Group of Research in Ruminants (G2R), Department of Animal and Food Sciences, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Fiber is essential for rumen health, microbial fermentation, and the energy supply of herbivores. Even though the study of fecal fiber contents (neutral detergent fiber NDF, acid detergent fiber ADF, and acid detergent lignin ADL) using near-infrared reflectance spectroscopy (NIRS) has allowed investigating nutritional ecology of different herbivore species, NIRS calibrations are species-specific and require a large number of samples for predictions. A multispecies calibration would be an advantage since samples from different herbivores could be used to calibrate a model capable of predicting the fecal fiber content of other herbivores.
View Article and Find Full Text PDFAntioxidants (Basel)
November 2024
Barts & The London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
The majority of naturally occurring mutations of the human gene , are associated with reduced or completely absent xanthine oxidoreductase (XOR) activity, leading to a disease known as classical xanthinuria, which is due to the accumulation and excretion of xanthine in urine. Three types of classical xanthinuria have been identified: type I, characterised by XOR deficiency, type II, caused by XOR and aldehyde oxidase (AO) deficiency, and type III due to XOR, AO, and sulphite oxidase (SO) deficiency. Type I and II are considered rare autosomal recessive disorders, a condition where two copies of the mutated gene must be present to develop the disease or trait.
View Article and Find Full Text PDFCurr Microbiol
January 2025
Federal Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, 60-let Oktyabrya prospect, 7, bld. 2, Moscow, Russia, 117312.
A novel Gram-negative, motile, rod-shaped bacterium, designated 4137-cl, was isolated from a thermal spring of North Ossetia (Russian Federation). Strain 4137-cl grew at 30-50 °C (optimum 42 °C) with 0-3.5% NaCl (optimum 0-0.
View Article and Find Full Text PDFCytotechnology
February 2025
Department of Physiology, Faculty of Medicine, Pamukkale University, Denizli, Türkiye.
S-Sulfocysteine (SSC) is a metabolite derived from the metabolism of sulfur-containing amino acids. It has been implicated in neurotoxicity observed in children with sulfite oxidase deficiency. The aim of our study was to confirm the neurotoxic effects of SSC using a mouse hippocampal cell line (HT-22) and to investigate the role of apoptosis in these effects, especially in terms of caspase-3 activation and genotoxicity.
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