Kraft lignin (KL) was successfully depolymerized into polyols of moderately high hydroxyl number and yield with moderately low weight-average molecular weight (Mw) via direct hydrolysis using NaOH as a catalyst, without any organic solvent/capping agent. The effects of process parameters including reaction temperature, reaction time, NaOH/lignin ratio (w/w) and substrate concentration were investigated and the polyols/depolymerized lignins (DLs) obtained were characterized with GPC-UV, FTIR-ATR, (1)H NMR, Elemental & TOC analyzer. The best operating conditions appeared to be at 250°C, 1h, and NaOH/lignin ratio ≈0.28 with 20 wt.% substrate concentration, leading to <0.5% solid residues and ∼92% yield of DL (aliphatic-hydroxyl number ≈352 mg KOH/mg and Mw≈3310 g/mole), suitable for replacement of polyols in polyurethane foam synthesis. The overall % carbon recovery under the above best conditions was ∼90%. A higher temperature favored reduced Mw of the polyols while a longer reaction time promoted dehydration/condensation reactions.
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http://dx.doi.org/10.1016/j.biortech.2013.03.199 | DOI Listing |
Anal Chim Acta
January 2025
School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, 430205, China. Electronic address:
Background: Carbosulfan (CBS) is a widely used carbamate pesticide in agricultural production, its easy decomposition into hypertoxic carbofuran poses serious threats to human health and food safety. Therefore, sensitive and accurate detection of CBS is of significant importance. Conventional chromatography-based techniques require expensive instruments and complicated sample pretreatment, limiting their application for fast detection.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Institute of Future Food Technology, JITRI, Yixing 214200, China. Electronic address:
Starch is a widely used and economically important polymer; however, its industrial applications are limited by certain shortcomings, such as retrogradation and high digestion rate. To overcome these limitations, native starches can be hydrolyzed by β-amylase, resulting in the production of β-limit dextrin (β-LD) and maltose as a co-product. β-LD retains the original inner core structure of its parent amylopectin and contains truncated external chains that is not prone to form exterior chain helical.
View Article and Find Full Text PDFBMC Bioinformatics
January 2025
International Institute "Solution Chemistry of Advanced Materials and Technologies", ITMO University, Saint-Petersburg, Russian Federation, 191002.
Background: Deoxyribozymes or DNAzymes represent artificial short DNA sequences bearing many catalytic properties. In particular, DNAzymes able to cleave RNA sequences have a huge potential in gene therapy and sequence-specific analytic detection of disease markers. This activity is provided by catalytic cores able to perform site-specific hydrolysis of the phosphodiester bond of an RNA substrate.
View Article and Find Full Text PDFClin Chem Lab Med
January 2025
Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Objectives: Urinary steroid profiling after hydrolysis of conjugates is an emerging tool to differentiate aggressive adrenocortical carcinomas (ACC) from benign adrenocortical adenomas (ACA). However, the shortcomings of deconjugation are the lack of standardized and fully validated hydrolysis protocols and the loss of information about the originally conjugated form of the steroids. This study aimed to evaluate the quality of the deconjugation process and investigate novel diagnostic biomarkers in urine without enzymatic hydrolysis.
View Article and Find Full Text PDFWater Res
December 2024
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science & Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China. Electronic address:
Lipids offer high energy recovery potential during anaerobic digestion (AD), but their hydrolysis generates long-chain fatty acids (LCFAs), which are difficult to biodegrade. The introduction of microbial electrolysis cells has been widely recognized as a promising strategy to enhance AD. However, it is still under debate whether the electrical circuit needs to be connected, as certain electrodes with large specific surface areas have been reported to enhance direct interspecies electron transfer (DIET) without requiring an external power supply.
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