Huajiao ( Maxim.) is extensively cultivated in various countries, including China, Korea, and India, owing to its adaptability to diverse environments. This study comprehensively analyzed the volatile substance composition of 14 varieties of red huajiao with distinct geographical origins.
View Article and Find Full Text PDFJ Agric Food Chem
August 2024
Flavors and fragrances (F&F) are interesting organic compounds in chemistry. These compounds are widely used in the food, cosmetic, and medical industries. Enzymatic synthesis exhibits several advantages over natural extraction and chemical preparation, including a high yield, stable quality, mildness, and environmental friendliness.
View Article and Find Full Text PDFAsymmetric catalytic processes promoted by N-heterocyclic carbenes (NHCs) hold great potential for the sustainable preparation of chiral molecules. However, catalyzing the reactions by manipulating the reactive intermediates is challenging. We report herein that the known NHC-catalyzed [3 + 2] annulation reaction between ketimine and enal can also be turned into a [2 + 3] annulation reaction for the highly enantioselective direct synthesis of trifluoroethyl 3,2'-spirooxindole γ-lactams (4) through timely catalysis of the intermediates.
View Article and Find Full Text PDFalcohol dehydrogenase (ADH) and ketoreductase from . CA49 (KRED12) exhibit different chemoselectivity and stereoselectivity toward a substrate with both keto and aldehyde carbonyl groups. ADH selectively reduces the keto carbonyl group while retaining the aldehyde carbonyl group, producing optically pure -alcohols.
View Article and Find Full Text PDFBackground: Hyperlipidemia is characterized by abnormally elevated blood lipids. Quinoa saponins (QS) have multiple pharmacological activities, including antitumor, bactericidal and immune-enhancing effects. However, the lipid-lowering effect and mechanisms of QS in vivo have been scarcely reported.
View Article and Find Full Text PDFThe impact of pesticides on reproductive health has been increasingly recognized. β-cypermethrin (β-CYP) and emamectin benzoate (EMB) are commonly used with agricultural workers. There are few published studies on the effects of combined poisoning of these two pesticides on the reproductive system.
View Article and Find Full Text PDFHepatitis B virus (HBV) capsid assembly modulators (CAMs) represent a promising therapeutic approach for the treatment of HBV infection. In this study, we designed and synthesized five series of benzamide derivatives based on a multisite-binding strategy at the tolerant region and diversity modification in the solvent-exposed region. Among them, thioureidobenzamide compound exhibited significantly increased anti-HBV activity in HepAD38 (EC = 0.
View Article and Find Full Text PDFQuinoa saponins have outstanding activity, and there are an increasing number of extraction methods, but there are few research programs on green preparation technology. The extraction conditions of quinoa saponins with deep eutectic solvents (DESs) were optimized by single-factor experiments combined with response surface methodology. The antioxidant capacity of saponins extracted by DESs and traditional methods was evaluated by the DPPH clearance rate, iron ion chelation rate and potassium ferricyanide reducing power.
View Article and Find Full Text PDFRare ginsenosides have already been widely applied in many fields, including health food and bio-medicine. The human being can expose to rare ginsenosides directly or indirectly increasingly. However, there are few studies on the safety assessment of rare ginsenoside mixtures.
View Article and Find Full Text PDFColorectal cancer (CRC) is one of the most common malignancies causing the third highest mortality rate in the world. It is particularly urgent to explore effective therapeutic strategies to overcome this disease. We identified a novel benzothiazole derivative (BTD) that may serve as a potentially effective agent against CRC.
View Article and Find Full Text PDFMonoterpene pyridine alkaloids (MTPAs) are alkaloids derived from iridoid glycosides (IGs). The common molecular structure of MTPAs is the pyridine ring, while some of them have a cyclopenta[c]pyridine skeleton. Some compounds containing this structure are potentially bioactive medicinal agents.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
February 2023
Titanium nanoparticles and pyrethroid pesticides are now being widely used in industrial, agriculture, and biomedical applications. In recent years, their health safety profiles have aroused concerns among health scientists. This study mainly explored the combined effects of titanium dioxide nanoparticles (TiONPs) and cypermethrin (CYP) on reproductive toxicity in male rats by gavage for 90 days.
View Article and Find Full Text PDFA highly efficient potassium carbonate-mediated [3 + 2] cycloaddition reaction of hydrazonoyl chlorides with cinnamic aldehydes to furnish multi-substituted pyrazoles under nontoxic and mild conditions has been developed. A plausible stepwise cycloaddition reaction mechanism is proposed. This protocol featured broad substrate coverage, good functional group tolerance, wide scalability, and operational simplicity, as well as conveniently constructed pyrazole scaffolds.
View Article and Find Full Text PDFTwo water-soluble red color-related proteins with the molecular masses of 24 and 73 kDa were purified from the shell of Procambarus clarkii. Initial color changes of these two proteins were detected at 30 °C and the large amount of red precipitate were obtained at 80 °C. PAGE analysis showed that the 24 kDa protein was the monomer, while the 73 kDa protein was the trimer.
View Article and Find Full Text PDFA new fluorescent probe made from ()-2-(benzo[d]thiazol-2-yl)-3-(6-hydroxynaphthalen-2-yl) acrylonitrile (Probe 1) was synthesized for the determination of bisulfite concentrations in real food samples (red wine and sugar). Adding bisulfite to a Probe 1 solution caused a marked decrease in fluorescence intensity and a visual color change from yellow to light yellow. This distinct color response indicates that Probe 1 could be used as a visual sensor for bisulfite.
View Article and Find Full Text PDFA new highly selective and visible colorimetric fluorescent probe (probe 1) was developed to detect hydrazine (NH) concentration in real water samples. As different concentrations of NH were added, the color of the probe solution was graded gradually from colorless to pink, which could be observed by the naked eye under UV light at 365 nm. Our research indicates that probe 1 offers a certain practical significance for use as a visible detection agent to detect NH efficiently by distinct color response.
View Article and Find Full Text PDFIn this work, crystalline structural variations of cellulose during pulp beating of tobacco stems were characterized through X-ray diffraction (XRD) and FT-IR spectroscopy. The results showed that the correlation between the cellulose crystallinity index and the degree of beating was not a linear but an initially upward and then downward trend followed by a repeating fluctuation as a result of the beating action on amorphous regions first and then on crystalline cellulose. It was proposed that the whole beating process might be presumably divided into two phases in the case of the evolution of the crystallinity index.
View Article and Find Full Text PDFA cobalt porphyrin (CY-B) was presented, and its interaction with tobacco-specific nitrosamines (TSNAs) was investigated by UV-Vis spectroscopy and high-resolution mass spectrometry. The results revealed that the stoichiometry of the host-guest interaction was 1:2 and that the binding constant between CY-B and TSNAs was within the range of 0.78×10(8)-7.
View Article and Find Full Text PDFL-beta-Haloalanines are physiologically active unnatural amino acids and they are useful intermediates for the synthesis of natural and unnatural amino acids, S-linked glycopeptides, and lanthionines. In general L-beta-haloalanines were prepared predominantly from L-serine via functional group transformation. Here we reported an alternative approach for the preparation of L-beta-haloalanines via halogenation of protected L-cysteine esters which was obtained from L-cysteine or L-cystine, respectively.
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