This study deployed ultrasonic-assisted extraction (UAE), combined with natural deep eutectic solvents (NADES), to extract phenolics and flavonoids from the black mulberry fruit, and the antioxidant activity was examined. The extraction yields of NADES-based UAE were assessed based on the yields of phenolics and flavonoids extracted from the black mulberry fruit. This study selected the molar ratios of hydrogen bond acceptors (HBA) and hydrogen bond donors HBD at 1:2 from previous studies.
View Article and Find Full Text PDFThis research combined ultrasonic-assisted extraction (UAE) and natural deep eutectic solvent (NADES) to recover phenolic and flavonoid components from mangosteen rind. The antioxidant activities were determined using DPPH, ABTS, and hydroxyl assays. NADES prepared from lactic and 1,2-propanediol had the highest extraction efficiency based on the total flavonoid content (TFC) and phenolic contents (TPC).
View Article and Find Full Text PDFObjective: Obesity and associated liver disease are a growing public health concern. Pharmacological agents to treat non-alcoholic fatty liver disease are limited. FGF21, a hormone secreted by the liver and potent metabolic modulator, is a promising therapeutic target for this indication with several analogs currently in clinical development.
View Article and Find Full Text PDFLinagliptin is a highly specific, long-acting inhibitor that is used as an orally administrable agent for type-2 diabetes treatment. Because only the R-enantiomer is of clinical use, we developed a capillary electrophoresis method for the determination of the enantiomeric impurity of this compound. Carboxymethyl-β-cyclodextrin was selected as the chiral selector for the separation of linagliptin enantiomers.
View Article and Find Full Text PDFThe study of the pressure response by NMR spectroscopy provides information on the thermodynamics of conformational equilibria in proteins and nucleic acids. For obtaining a database for expected pressure effects on free nucleotides and nucleotides bound in macromolecular complexes, the pressure response of H chemical shifts and J-coupling constants of the purine 5'-ribonucleotides AMP, ADP, ATP, GMP, GDP, and GTP were studied in the absence and presence of Mg-ions. Experiments are supported by quantum-chemical calculations of populations and chemical shift differences in order to corroborate structural interpretations and to estimate missing data for AMP.
View Article and Find Full Text PDFHigh pressure NMR spectroscopy is a powerful method for identifying rare conformational states of proteins from the pressure response of their chemical shifts. Many proteins have bound adenine nucleotides at their active centers, in most cases in a complex with Mg-ions. The P NMR signals of phosphate groups of the nucleotides can be used as probes for conformational transitions in the proteins themselves.
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