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A rapid and accurate qualitative and quantitative method based on ultra-high performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS) was established for the determination of various trace aroma and flavor substances and their derivatives in baijiu. Samples were centrifuged at high speed, filtered and separated on a Hypersil Gold C18 (150 mm × 2.1 mm, 1.9 μm) column before analysis. The results showed that the pretreatment process allowed multi-component analysis of baijiu without extraction using ethanol or other organic solvents within 16 minutes. The calibration curves established using a mixed standard solution of 17 amino acids, 4 bioamines and 11 non-volatile organic acids exhibited good linearity (R2 > 0.990), and the detection limits and quantitation limits were relatively low for all analytes, which meet the requirements of the compositional analysis of baijiu. The average recoveries for all analytes were 71.92%–117.45%, with relative standard deviations (RSDs) of 0.46%–5.48%. The developed method had good recovery, precision, and stability for all analytes. Therefore, this method has the advantages of simple operation, high sensitivity, and good repeatability, and is of reference significance for the analysis of the types and contents of other non-volatile flavor substances in baijiu.

Chestnut rose fruit, known as "Three King fruits", has high edible value and medicinal value. Polyphenols are the second major functional component of chestnut rose fruit with pharmacological and health functions such as antioxidant, regulation of glucose and lipid metabolism, anti-inflammatory and bacteriostatic, antialcoholism and liver protection, and have great potential for food development. This review summarized the research progress of the classification, extraction, qualitative and quantitative analysis, and bioactivity of chestnut rose fruit polyphenols in recent years and prospected the future development direction.

The objective of this work was to investigate the protective effect and underlying mechanism of a bioactive peptide from coix seeds (Coix lacryma-jobi) on high glucose-injured human umbilical vein endothelial cells (HUVEC). HUVEC injured by 30 mmol/L glucose were treated with different concentrations of the peptide and were evaluated for the secretion of nitric oxide (NO) by the nitrate reductase method. The content of reactive oxygen species (ROS) was detected by flow cytometry. Cell apoptosis was detected by Annexin V-FITC/PI double staining. Quantitative real-time polymerase chain reaction (qPCR) was applied to detect the expression of inflammation-related genes. The results showed that NO secretion was decreased by 28.72% (P < 0.05), ROS secretion was increased by 96.19% (P < 0.05), and the expression of the ICAM-1, IL-6, MCP-1 and VCAM genes was significantly increased in HUVEC induced by high glucose compared with the normal control group. The prolongation of high glucose treatment time significantly increased the apoptosis rate of HUVECs, and after 14 days, the apoptosis rate of HUVECs was 1.61 times higher than that in the normal control group. Treatment with the peptide at all concentrations increased NO secretion, decreased ROS content and the expression of inflammatory genes and reduced cell apoptosis. In summary, the coix seed biopeptide possesses a protective effect on high glucose-injured HUVEC.

An ultra-high performance liquid chromatography-high resolution mass spectrometric (UPLC-HRMS) method was developed, optimized and applied to analyze the bitter compound trihydroxyoctadecenoic acid in Chinese baijiu. The samples were diluted and filtered through a 0.22 μm membrane before analysis. Acetonitrile was selected as the organic phase and 0.1% formic acid as the aqueous phase with a flow rate of 0.3 mL/min and an injection volume of 2 μL. The analyte was separated on a Hypersic Gold (100 mm × 2.1 mm, 1.9 μm) column by gradient elution, and qualitative analysis was achieved by comparison of secondary daughter ions and theoretical simulation of molecular ion fragment structures using the Mass Frontier 8.0 software, which could avoid false positive results. This method had the advantages of simple pretreatment, fast analysis, low detection limit (0.2 ng/mL) and high accuracy, and could meet the requirements for the detection of baijiu samples. This method was used to study the change in the content of trihydroxyoctaenoic acid during the production process of Maotai-flavor baijiu. The results showed that with the prolongation of fermentation time, a large amount of linoleic acid in the raw materials was likely to be oxidized and decomposed into trihydroxyoctadecenoic acid, and then transferred into the base liquor by distillation. The content of trihydroxyoctadecenoic acid in the base liquor did not obviously change during storage, indicating that it was affected little by storage time. The content of trihydroxyoctadecenoic acid in Maotai-flavor base liquor was lowest among the three typical bodies of Maotai-flavor baijiu, so Maotai-flavor base liquor could be used as one of the major base liquors for packaged products.

Manganese dioxide (MnO2) nanosheets with a well-defined 2D structure can serve as catalase (CAT) and superoxide dismutase (SOD) mimics and hold a high potential in regulating the oxidative stress of atopic dermatitis (AD). However, facile, time-saving, and scalable synthesis of high-activity MnO2 nanosheets is still challenging. Here, we report a one-step oxidative synthesis strategy of MnO2 nanosheets and explore its potential as CAT and SOD mimics to exert antioxidant functions. After further gelatinization by integrating MnO2 nanosheets into a poly-(ethylene glycol)-diacrylate (PEGDA) polymer (PGM hydrogel), the obtained PGM hydrogel, characterized by well-designed cross-linking density and moisture retention, retains high antioxidation and cytoprotection ability. In AD-bearing mouse models, the PGM hydrogel facilitates the recovery of the impaired mice skin, reducing the severity score, scratching numbers, epidermal thickness, and immune factors, including mast cells, IgE antibodies, and inflammatory cytokines IL-4 and IL-10. Such a simple and reliable approach paves the way for the scale synthesis of MnO2 nanosheets and its practical application as antioxidative and immunoregulation agents for AD therapy. [ABSTRACT FROM AUTHOR]