Carbohydrates generally occur in several conformations that may differ among themselves by energy values that are smaller than the accuracy of the most sophisticated theoretical methods used to determine them. In addition, the preferential orientations of the hydroxyl groups of these molecules cannot be identified by any experimental technique. Therefore, a method that is able to validate the absolute conformations (i.e., consisting of the orientations of the hydroxyl groups) of carbohydrates would be helpful to improve our knowledge about monosaccharides. SR has been used for this purpose, and here, we present a test to measure the specific rotation (SR) ability of a molecule that possesses not only many conformations, but also four adjacent chiral centers. The results show that the final SR value is a weighted average of a global property (obtained for each conformation), and the latter by its turn is influenced by each chiral center in a multi chiral system. By comparing the SR values calculated for the most abundant anomers of xylopyranose with those of the corresponding monochiral analogs obtained by saturation of three different chiral centers each time, the influence of each center on the global property is confirmed.
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http://dx.doi.org/10.1039/c4cp01316f | DOI Listing |
Plant Foods Hum Nutr
January 2025
College of Food Science and Engineering, Ningbo University, Ningbo, 315832, PR China.
Quinoa polysaccharides have attracted significant research interest in recent years due to their diverse biological activities, including antiviral, anti-inflammatory, antioxidant, and immunoregulatory properties. These attributes align with the growing global demand for natural, functional food ingredients, positioning quinoa polysaccharides as a valuable resource in food science and technology. This review presents an overview of the various bioactivities of quinoa polysaccharides, critically evaluates the methods used for their extraction and purification, describes their structural characteristics, and discusses their practical applications across multiple areas within the food industry, including food additives, meat products, health foods, and innovative food packaging.
View Article and Find Full Text PDFChem Soc Rev
January 2025
Department of Chemistry, Center of Chemistry for Frontier Technologies, Zhejiang University, Hangzhou 310027, China.
Carbon dioxide capture has attracted worldwide attention because CO emissions cause global warming and exacerbate climate change. Ionic liquids (ILs) have good application prospects in carbon capture due to their excellent properties, which provide a new chance to develop efficient and reversible carbon capture systems. This paper reviews the recent progress in CO chemical absorption by ILs, such as N-site, O-site, C-site, and multi-site functionalized ILs.
View Article and Find Full Text PDFCrit Rev Microbiol
January 2025
Oral Microbiology, Bristol Dental School, University of Bristol, United Kingdom.
This review discusses the chemical properties, synthesis and detection, and biological functions of a molecular group of cis-2-unsaturated fatty acids, containing fatty acid carbon chains of various lengths and cis double-bond configurations, known as the diffusible signaling factor family (DSFF). Early postulation of the conserved nature of the DSFF among Gram-negative bacteria have now been challenged by the latest evidences that unraveled their presence in a various other distinct microorganisms. Over the last decade, a significant depth and breadth of understanding has been made on the multifaceted functions of DSFFs among bacteria, and their interactions with evolutionarily divergent fungi, plants insects and small animals.
View Article and Find Full Text PDFCNS Neurosci Ther
January 2025
Department of Otolaryngology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.
Background: Sudden sensorineural hearing loss (SSNHL) is associated with abnormal changes in the brain's central nervous system. Previous studies on the brain networks of SSNHL have primarily focused on functional connectivity within the brain. However, in addition to functional connectivity, structural connectivity also plays a crucial role in brain networks.
View Article and Find Full Text PDFAnn Bot
January 2025
Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, TW20 0EX, Egham, United Kingdom.
The biomechanical, morphological and ecophysiological properties of plant seed/fruit structures are adaptations that support survival in unpredictable environments. High phenotypic variability of noxious and invasive weed species such as Raphanus raphanistrum (wild radish) allow diversification into new environmental niches. Dry indehiscent fruits (thick and lignified pericarp [fruit coat] enclosing seeds) have evolved many times independently.
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