Bioactive macromolecule mining is important for the functional chemome analysis of traditional Chinese vinegar. In this study, we isolated and characterized carbohydrate-containing macromolecules from Shanxi aged vinegar (CCMSAV) and evaluated their immunomodulatory activity. The isolation process involved ethanol precipitation, deproteinization, decolorization, and DEAE-650 M column chromatography, resulting in the acquisition of four sub-fractions. All sub-fractions exhibited a molecular weight range of 6.92 to 16.71 kDa and were composed of 10 types of monosaccharides. Comparative analysis of these sub-fractions with two melanoidins exhibited similarities in elemental composition, spectral signature, and pyrolytic characteristics. Immunological assays confirmed the significantly enhanced cell viability, phagocytic activity, and secretion of nitric oxide, tumor necrosis factor (TNF)-α and interleukin (IL)-6 in RAW264.7 cells by all four sub-fractions. Further investigation of the immunomodulatory mechanism revealed that SAV-RP70-X, the most potent purified sub-fraction, enhanced aerobic glycolysis in macrophages and activated Toll-like receptor 2 (TLR2), TLR4, mannose receptor (MR), scavenger receptor (SR), and the dendritic cell-associated C-type lectin-1 receptor (Dectin-1). Furthermore, the activation of macrophages was associated with the MyD88/PI3K/Akt/NF-κB signaling pathway. Methylation analysis revealed that 1,4-Xylp was the most abundant glycosidic linkage in SAV-RP70-X.

We explored the effect of microwave heating (MWH) and electric heating (ETH) on the volatile compounds (VCs) of pepper (Capsicum annuum L.). The spectral of the produced melanoidins by baking were used to screen samples with similar baking degrees. Mass spectrometry was used to detect the differences of VCs in samples. The results showed a dose-dependent effect between the intensity of absorption and fluorescence of melanoidins, which can be utilized as indicators for assessment baking degree. MWH samples produced larger variety of VCs than ETH. Changes in the variety and content of VCs infer changes in the flavor of pepper. According to the mechanism of Maillard reaction (MR) and MWH, it was deduced that MWH changes the type of chemical reaction in MR by affecting the distribution of valence electrons in the compounds. Therefore, MWH can be used as a novel method to modify the VCs and flavor of peppers.

Abstract Bioactive macromolecule mining is important for the functional chemome dissection of traditional Chinese vinegar. Here, saccharide-bearing macromolecules in Shanxi aged vinegar (SBMSAV) were isolated, characterized, and their immunomodulatory activity was evaluated. Four sub-fractions were obtained through ethanol precipitation followed by refining and DEAE-650M column chromatography. All sub-fractions had a maximum molecular weight of more than 2,667 kDa, with 10 types of monosaccharides identified. Comparative analysis of these sub-fractions with melanoidins from real food and model systems showed that all four sub-fractions had similarities with both melanoidins in elemental composition, spectral signature, and pyrolytic characteristics. Immunological assays showed that the four sub-fractions significantly improved macrophage cell viability and phagocytic activity, and promoted the secretion of NO, TNF-α, and IL-6. Immunomodulatory mechanism investigation indicated that SBMSAV enhanced aerobic glycolysis in macrophages and were recognized through TLR2, TLR4, MR, SR, and Dectin-1. Additionally, the MyD88/PI3K/Akt/NF-κB signaling pathway was found to be involved in the activation of macrophages.

To investigate the formation of typical melanoidin polymers, methylglyoxal (MGO) with NH3 or alanine (Ala) was used to form coloured compounds, with glyoxal or acetone used as controls. The products were characterised using chromatography, mass spectrometry, and spectroscopy. Spectroscopic results showed that the coloured compounds formed were similar to melanoidins in food. GC-MS results showed that the MGO-based reaction generated similar volatile compounds using the Maillard reaction. Mass spectrometry showed that the molecular weights of structural units in the polymers were mainly 162, 169, and 176 Da, and these could be reassembled using the basic units derived from MGO alone or in combination with nitrogen. Hence, polymers recombined using basic structural units should be considered while determining melanoidin biomarkers. The preparation of coloured compounds using MGO with NH3 can be used as a novel method to produce the control compounds for melanoidin after process optimization.

Melanoidins, are of increasing interest for their potential biological activities. However, little knowledge is available on their structure. In the present study, vinegar, coffee and model melanoidins were degraded by NaBH4, and the resultant reaction products were characterised by chromatography, mass spectrometry and spectrometry methods to elucidate the mechanism of formation of melanoidin skeleton molecules. The study identified a typical polymer with a molecular weight (MW) interval of 74 Da, which was polymerised by aldol condensation and reduced by NaBH4, followed by intermolecular dehydration. MW of the theoretically derived typical polymers matched the detected polymers, validating the speculated pathway involved in the formation of melanoidins skeleton molecules. The study also revealed that melanoidins from different sources contain polymers with the same MW and different binding preferences, contributing to the heterogeneity of melanoidins. Overall, these findings indicated that the identified polymers could be used as potential candidate biomarkers for melanoidins.

食醋是世界范围内广泛使用的酸味调味品之一.随着对食醋研究的深入,食醋行业的科技创新也在不断加强.该文章基于专利文献,以数据思维为导向,借助"智慧芽"分析平台对当前世界范围内食醋领域非失效专利进行了可视化分析.宏观上,对食醋领域专利类型、专利申请趋势和专利技术生命周期进行了分析,比较展示了专利申请人及区域分布;微观上,通过专利被引分析,分别识别了发明和实用新型专利中的重点专利.结合国际专利分类及专利关键词词云和3D专利地图分析,判别了食醋领域发明和实用新型专利的技术主题.研究首次从专利可视化角度对食醋领域专利进行剖析,以期反映食醋行业科技创新的现状和进展、热点和趋势,并为食醋领域相关研究提供参考.

To decipher the formation mechanism of nitrogen-free substructures in melanoidins, methylglyoxal or 3-deoxy-glucosone was used as a substrate to react by aldol reaction under different pH conditionst. The obtained products were characterised by chromatography, mass spectrometry, and spectroscopic methods. Overall, the molecular weights of the polymers structural units varied mainly within 54-56 and 72-74 Da, respectively, due to the different dehydration extent of beta-hydroxy aldehyde or ketones, and uneven reduction by NaBH4. Moreover, the nitrogen-free substructures formed by this reaction can cross-link with gluten and dextran to form melanoidins. Therefore, the nitrogen-free substructures by this reaction to formed with units of 54-56 and 72-74 Da, which are similar as the typical polymers in food melanoidins. It is inferred that the typical polymers in food may also be formed by this pathway and which can be used as a detectable biomarker in melanoidins.