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Postbiotics are inanimate microbial cells and/or their components as well as microecological preparations made from their metabolites, which are beneficial to the health of the host. Postbiotics can regulate intestinal microbial balance, enhance immunity, and have anti-inflammatory and antibacterial effects. Compared with probiotics, living bacterial cells, postbiotics are safer, and more stable, effective and convenient. This article summarizes the origin, microbial sources, preparation methods and advantages of postbiotics, and elucidates the mechanisms of action of postbiotics in comparison with those of probiotics. In addition, it introduces readers to the applications of postbiotics as functional food supplements, food quality improvers, food preservatives and detoxifying agents in foods. We believe that as the definition, classification, and functional components of postbiotics become clearer, they will be more widely used in the fields of foods, nutraceuticals, foods for special medical purpose, infant foods, and personal care products. The development of postbiotics will also promote the leapfrog development of basic and applied science.

Long noncoding RNAs (lncRNAs) have been widely proven to be involved in liver lipid homeostasis. Herein, we identify an upregulated lncRNA named lncRP11-675F6.3 in response to rapamycin treatment using a microarray in HepG2 cells. Knockdown of lncRP11-675F6.3 leads to a significant reduction in apolipoprotein 100 (ApoB100), microsomal triglyceride transfer protein (MTTP), ApoE and ApoC3 with increased cellular triglyceride level and autophagy. Furthermore, we find that ApoB100 is obviously colocalized with GFP-LC3 in autophagosomes when lncRP11-675F6. 3 is knocked down, indicating that elevated triglyceride accumulation likely related to autophagy induces the degradation of ApoB100 and impairs very low-density lipoprotein (VLDL) assembly. We then identify and validate that hexokinase 1 (HK1) acts as the binding protein of lncRP11-675F6.3 and mediates triglyceride regulation and cell autophagy. More importantly, we find that lncRP11-675F6.3 and HK1 attenuate high fat diet induced nonalcoholic fatty liver disease (NAFLD) by regulating VLDL-related proteins and autophagy. In conclusion, this study reveals that lncRP11-675F6.3 is potentially involved in the downstream of mTOR signaling pathway and the regulatory network of hepatic triglyceride metabolism in cooperation with its interacting protein HK1, which may provide a new target for fatty liver disorder treatment.

Hydrogen peroxide and activated carbon were separately used for decolorization of Thesium chinense Turcz polysaccharides. The physical characteristics of the two decolorized samples were analyzed by X-ray diffractometry (XRD), thermogravimetry, laser particle size analyzer and rheometer, and their inhibitory activities against the proliferation of liver cancer cells were compared, as well as their effects on the gelation temperature of κ-carrageenan. The results showed that the crystalline structure of the activated carbon-treated sample was more obvious in the XRD pattern. Its apparent viscosity was higher than that of the hydrogen peroxide-treated sample at the same concentration. The thermogravimetric curve showed that the thermal decomposition degree of the hydrogen peroxide-treated sample was higher than that of the activated carbon-treated sample (mass loss percentage of 59.33% and 53.21%, respectively). At concentrations of 6–10 mg/mL, the activated carbon-treated sample showed inhibitory activity against the proliferation of HepG2 cells, while the hydrogen peroxide-treated samples did not have any inhibitory effect in the concentration range of 1–10 mg/mL. Furthermore, the increase in temperature hysteresis of blends of the activated carbon-treated-treated polysaccharides with κ-carrageenan was greater than that in blends of the HTP-treated polysaccharides with κ-carrageenan. Therefore, different decolorization methods can affect the structure and application characteristics of Thesium chinense Turcz. polysaccharides.

In order to explore the effect of Chuzhou chrysanthemum powder application in bread processing on dough characteristics and bread flavor and antioxidant activity, the thermal and mechanical properties of dough with added Chuzhou chrysanthemum powder were measured using Mixolab 2, and the volatile flavor compounds in the resulting bread were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS). In addition, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) cation radical scavenging capacity and the total flavonoid content of the bread were determined. The results showed that the water absorption rate of dough significantly increased while the peak viscosity and setback of starch decreased upon addition of Chuzhou chrysanthemum powder. Compared with the control bread, the content of flavor components in Chuzhou chrysanthemum incorporated bread was higher, and d-camphor was found to be the characteristic flavor component of Chuzhou chrysanthemum. The volatile flavor components in the samples with and without Chuzhou chrysanthemum were obviously different according to principal component analysis (PCA). The total flavonoid content of Chuzhou chrysanthemum incorporated bread was 260.47 mg/100 g, which was significantly higher than that of the control bread, and the DPPH and ABTS cation radical scavenging activities were higher than those of the control bread. In conclusion, addition of Chuzhou chrysanthemum powder to bread can enrich the flavor components and improve the antioxidant activity of bread, which provides a reference for the application of Chuzhou chrysanthemum in bakery foods.

For the position synchronization control problem of multiple nonlinear manipulator systems, a bounded distributed cooperative controller is designed in this paper. Based on a fixed‐time position observer, a distributed finite‐time synchronization controller is designed by using the saturated control technique and homogenous system theory. Compared with the existing results, the proposed distributed cooperative control algorithm not only guarantees finite‐time convergence but also satisfies the input saturation. Finally, some numerical simulation results are presented to verify the feasibility of the theory results with six‐degree‐of‐freedom robots. [ABSTRACT FROM AUTHOR]

The development of effective therapeutics against COVID‐19 requires a thorough understanding of the receptor recognition mechanism of the SARS‐CoV‐2 spike (S) protein. Here the multidomain collective dynamics on the trimer of the spike protein has been analyzed using normal mode analysis (NMA). A common nanomechanical profile was identified in the spike proteins of SARS‐CoV‐2 and its variants. The profile involves collective vibrations of the receptor‐binding domain (RBD) and the N‐terminal domain (NTD), which may mediate the physical interaction process. Quantitative analysis of the collective modes suggests a nanomechanical property involving large‐scale conformational changes, which explains the difference in receptor binding affinity among different variants. These results support the use of intrinsic global dynamics as a valuable perspective for studying the allosteric and functional mechanisms of the S protein. This approach also provides a low‐cost theoretical toolkit for screening potential pathogenic mutations and drug targets. [ABSTRACT FROM AUTHOR]