Volatile degradation products were isolated from a solution of L-dehydroascorbic acid in phosphate buffer solution of pH 2,4,6 and 8 heated under reflux for 3 h or left at 25 degrees C for 200 h. The products were identified by comparison of their gas chromatographic retention data, infra-red and mass spectra with those of authentic compounds. Fifteen products were identified, among which 12 had not yet been reported as degradation products of L-dehydroascorbic acid. Concentrations of 5 main degradation products, i.e. 3-hydroxy-2-pyrone, 2-furancarboxylic acid, 2-furaldehyde, acetic acid and 2-acetylfuran depended on the pH values and temperature; the presence of oxygen had no pronounced effect.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/BF01113311 | DOI Listing |
J Mol Model
January 2025
Shanxi Jiangyang Chemical Limited Company, Taiyuan, 030041, Shanxi, China.
Context: DNAN/DNB cocrystals, as a newly developed type of energetic material, possess superior safety and thermal stability, making them a suitable alternative to traditional melt-cast explosives. Nonetheless, an exploration of the thermal degradation dynamics of the said cocrystal composite has heretofore remained uncharted. Consequently, we engaged the ReaxFF/lg force field modality to delve into the thermal dissociation processes of the DNAN/DNB cocrystal assembly across a spectrum of temperatures, encompassing 2500, 2750, 3000, 3250, and 3500 K.
View Article and Find Full Text PDFBiotechnol Lett
January 2025
Extremophile and Productive Microorganisms Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Selenium is an essential element with various industrial and medical applications, hence the current considerable attention towards the genesis and utilization of SeNPs. SeNPs and other nanoparticles could be achieved via physical and chemical methods, but these methods would not only require expensive equipment and specific reagents but are also not always environment friendly. Biogenesis of SeNPs could therefore be considered as a less troublesome alternative, which opens an excellent window to the selenium and nanoparticles' world.
View Article and Find Full Text PDFPlant Foods Hum Nutr
January 2025
Facultad de Industrias Alimentarias, Universidad Nacional Agraria La Molina, Lima, Peru.
This review aimed to explore the impact of extrusion on Andean grains, such as quinoa, kañiwa, and kiwicha, highlighting their macromolecular transformations, technological innovations, and contributions to food security. These grains, which are rich in starch, high-quality proteins, and antioxidant compounds, are versatile raw materials for extrusion, a continuous and efficient process that combines high temperatures and pressures to transform structural and chemical components. Extrusion improves the digestibility of proteins and starches, encourages the formation of amylose-lipid complexes, and increases the solubility of dietary fiber.
View Article and Find Full Text PDFArch Dermatol Res
January 2025
Division of Gastroenterology and Hepatology, 200 1st Street SW, Rochester, MN, 55905, USA.
Background: Celiac disease (CeD) has shown an association with autoimmune disorders including vitiligo and alopecia areata (AA). Ritlecitinib, a JAK3 and TEC kinase family inhibitor, has been approved for treatment of patients with AA and is in late-stage development for vitiligo. Ritlecitinib inhibits cytotoxic T cells, NK cells, and B cells which play a role in the pathogenesis of CeD.
View Article and Find Full Text PDFInflamm Res
January 2025
Department of Otolaryngology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China.
Background: Allergic rhinitis (AR) represents a persistent inflammatory condition affecting the upper respiratory tract, characterized by abnormal initiation of the immunoglobulin E (IgE)-mediated cascade. Follicular helper T (Tfh) cells and regulatory T (Tfr) cells are pivotal in orchestrating the development of IgE production in AR patients. IL-35, an anti-inflammatory cytokine, secreted by various cellular subpopulations.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!