Characterization of complex lignin degradation products by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) requires a high sensitivity, which can be improved by use of optimized mobile phase additive. In this study, chromatographic separation and ionization efficiency for LC-MS analysis of lignin oligomers and lignin-derived phenolic compounds were compared among six different mobile phase additives. We found that acetic acid exhibits analytical performance superior to the other mobile phase additives for characterization of lignin degradation products by LC-(-)-ESI-MS/MS. The retention of phenolic compounds (PCs) containing carboxylic group was improved by using acidic additives instead of their ammonium salts. The use of acetic acid as an LC mobile phase additive enhanced the ionization efficiency of PCs in (-)-ESI-MS about 2 to 4 times higher than the other additives. The improved MS sensitivity with acetic acid yielded a higher coverage of fragment ions in LC-MS/MS analysis, leading to identification of four additional synthetic G-type lignin oligomers (LOs) than ammonium acetate. A similar degree of sensitivity enhancement was also demonstrated for degradation products from rice straw lignin using acetic acid additive over the others. The increased chromatographic retention and enhanced sensitivity of PCs and LOs provided by the use of acetic acid as an LC-(-)-ESI-MS mobile phase additive will facilitate structural analysis of lignin degradation products without relying on additional instrumentation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.chroma.2022.463598 | DOI Listing |
Alzheimers Dement
December 2024
University of Virginia, Charlottesville, VA, USA.
Background: Spousal care partners to people with dementia (PWD) have a higher rate of depression and anxiety when compared to similar age controls. Previous studies have suggested a role of gut microbiota in the pathophysiology of neuropsychiatric symptoms and Alzheimer's disease (AD). Thus, our study aims to: (1) determine the presence and severity of depression and anxiety in care partners of PWD, and (2) determine the concentrations of short chain fatty acids (SCFA), which are mainly produced by gut microbiota and are important in mediating gut microbiota effects, in the blood of care partners of PWD.
View Article and Find Full Text PDFChem Sci
December 2024
College of Science, Engineering and Environment, University of Newcastle Callaghan NSW 2308 Australia.
The inductive effect is a central concept in chemistry and is often exemplified by the p values of acetic acid derivatives. The reduction in p is canonically attributed to the reduction in the electron density of the carboxylate group through the inductive effect. However, wave functional theory calculations presented herein reveal that the charge density of the carboxylate group is not explained by the inductive effect.
View Article and Find Full Text PDF3 Biotech
January 2025
Department of Agronomy, Abdul Wali Khan University, Mardan, 23200 Khyber Pakhtunkhwa Pakistan.
Soil contamination with toxic heavy metals [such as aluminum (Al)] is becoming a serious global problem due to the rapid development of the social economy. Although plant growth-promoting rhizo-bacteria (PGPR) are the major protectants to alleviate metal toxicity, the study of these bacteria to ameliorate the toxic effects of Al is limited. Therefore, the present study was conducted to investigate the combined effects of different levels of (5 ppm and 10 ppm) of accession number of MT123456 on plant growth and biomass, photosynthetic pigments, gas exchange attributes, oxidative stress and response of antioxidant compounds (enzymatic and nonenzymatic), and their specific gene expression, sugars, nutritional status of the plant, organic acid exudation pattern and Al accumulation from the different parts of the plants, which was spiked with different levels of Al [0 µM (i.
View Article and Find Full Text PDFBMC Plant Biol
January 2025
Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, 650201, China.
Background: Space-induced plant mutagenesis, driven by cosmic radiation, offers a promising approach for the selective breeding of new plant varieties. By leveraging the unique environment of outer space, we successfully induced mutagenesis in 'Deqin' alfalfa and obtained a fast-growing mutant. However, the molecular mechanisms underlying its rapid growth remain poorly unexplored.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
Direct carbonylation of CH to CHCOOH provides a promising pathway for upgrading of natural gas to transportable liquid chemicals, in which high-efficiency CH activation and controllable C-C coupling are both critical but challenging. Herein, we report that highly efficient photo-driven carbonylation of CH with CO and O to CHCOOH is achieved over MoS-confined Rh-Zn atomic-pair in conjunction with TiO. It delivers a high CHCOOH productivity of 152.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!