Improving the shelf lives of fruits is challenging. The biodegradable polysaccharide pullulan exhibits excellent film-forming ability, gas barrier performance, and natural decomposability, making it an optimal material for fruit preservation. To overcome problems of high cost and film porosity of existing packaging technologies, we aimed to develop pullulan-based packaging paper to enhance the shelf lives of fruits. A thin paper coating comprising a mixture of 15 wt.% pullulan solution at various standard viscosities (75.6, 77.8, and 108.5 mPa·s) with tea polyphenols (15:2) and/or vitamin C (150:1) improved the oxygen transmission rate (120-160 cm3 m-2·24 h·0.1 MPa), water vapor transmission rate (<5.44 g·mm-1 m-2·h·kPa), maximum free radical clearance rate (>87%), and antibacterial properties of base packaging paper. Grapes wrapped with these pullulan-based papers exhibited less weight loss (>4.41%) and improved hardness (>16.4%) after 10 days of storage compared to those of control grapes (wrapped in untreated/base paper). Grapes wrapped with pullulan-based paper had >12.6 wt.% total soluble solids, >1.5 mg/g soluble protein, >0.44 wt.% titratable acidity, and ≥4.5 mg 100 g-1 ascorbic acid. Thus, pullulan-based paper may prolong the shelf life of grapes with operational convenience, offering immense value for fruit preservation.

In the present study, the synergistic bactericidal effect and mechanism of ultrasound (US) combined with Lauroyl Arginate Ethyl (LAE) against Salmonella Typhimurium were investigated. On this basis, the effect of US+LAE treatment on the washing of S. Typhimurium on the surface of onions and on the physical and chemical properties of onion during fresh-cutting and storage were studied. The results showed that treatment with US+LAE could significantly (P < 0.05) reduce the number of S. Typhimurium compared to US and LAE treatments alone, especially the treatment of US+LAE (230 W/cm2, 8 min, 71 μM) reduced S. Typhimurium by 8.82 log CFU/mL. Confocal laser scanning microscopy (CLSM), flow cytometry (FCM), protein and nucleic acid release and N-phenyl-l-naphthylamine (NPN) assays demonstrated that US+LAE disrupted the integrity and permeability of S. Typhimurium cell membranes. Reactive oxygen species (ROS) and malondialdehyde (MDA) assays indicated that US+LAE exacerbated oxidative stress and lipid peroxidation in cell membranes. Field emission scanning electron microscopy (FESEM) demonstrated that US+LAE treatment caused loss of cellular contents and led to cell crumpling and even lost the original cell morphology. US+LAE treatment caused a significant (P < 0.05) decrease in the number of S. Typhimurium on onions, but there was no significant (P > 0.05) effect on the color, hardness, weight and ascorbic acid content of onions. This study elucidated the synergistic antibacterial mechanism of US+LAE and verified the feasibility of bactericidal effect on the surface of onions, providing a theoretical basis for improving the safety of fresh produce in the food industry and to propose a new way to achieve the desired results.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, and, with increasing research on the tumor immune microenvironment (TIME), the immunosuppressive micro-environment of HCC hampers further application of immunotherapy, even though immunotherapy can provide survival benefits to patients with advanced liver cancer. Current studies suggest that polyamine metabolism is not only a key metabolic pathway for the formation of immunosuppressive phenotypes in tumor-associated macrophages (TAMs), but it is also profoundly involved in mitochondrial quality control signaling and the energy metabolism regulation process, so it is particularly important to further investigate the role of polyamine metabolism in the tumor microenvironment (TME). In this review, by summarizing the current research progress of key enzymes and substrates of the polyamine metabolic pathway in regulating TAMs and T cells, we propose that polyamine biosynthesis can intervene in the process of mitochondrial energy metabolism by affecting mitochondrial autophagy, which, in turn, regulates macrophage polarization and T cell differentiation. Polyamine metabolism may be a key target for the interactive dialog between HCC cells and immune cells such as TAMs, so interfering with polyamine metabolism may become an important entry point to break intercellular communication, providing new research space for developing polyamine metabolism-based therapy for HCC.

This phase 3 trial of PROTECT confirms the beneficial effects of teplizumab (anti-CD3 treatment) in type 1 diabetes and expands the indications from diabetes prevention (stage 2) to early treatment (stage 3). More efforts are needed to confirm the effects in the general population, with a higher dose, and with repeated dosing.

During the storage process, Chinese medicinal materials are susceptible to insect infestation due to their own nature and external storage factors. Infestation by insects can have varying impacts on the materials. In mild cases, it affects the appearance and reduces consumer purchasing power, while in severe cases, it affects the quality, reduces medicinal value, and introduces impurities such as insect bodies, excrement, and secretions, resulting in significant contamination of the medicinal materials. This study reviewed the rele-vant factors influencing insect infestation in Chinese medicinal materials and the compositional changes that occur after infestation and summarized maintenance measures for preventing insect infestation. Additionally, it provided an overview of detection techniques applicable to identifying insect infestation during the storage of Chinese medicinal materials. During the storage process, insect infestation is the result of the combined effects of biological factors(source, species, and population density of insects), intrinsic factors(moisture, chemical composition, and metabolism), and environmental factors(temperature, relative humidity, and oxygen content). After infestation, there are significant changes in the content of constituents in the medicinal materials. By implementing strict pre-storage inspections, regular maintenance after storage, and appropriate storage and maintenance methods, the occurrence of insect infestation can be reduced, and the preservation rate of Chinese medicinal materials can be improved. The storage and maintenance of Chinese medicinal materials are critical for ensuring their quality. Through scientifically standardized storage and strict adherence to operational management standards, the risk of insect infestation can be minimized, thus guaranteeing the quality of Chinese medicinal materials.

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Depuration and anhydrous living-preservation are two important and consecutive steps during the circulation of Pacific oyster (Crassostrea gigas), and two main factors in depuration, salinity and duration, are pivotal to posterior anhydrous living-preservation of C. gigas. In this work, the comprehensive effects of depuration salinity (26-38 g/L) and duration (0-72 h) on anhydrous living-preservation at 4 °C for 7 days were investigated in regard of mortality, biochemical indexes (fatty acids profile analysis, glycogen) and proteome changes as well. The results showed that the mortality of C. gigas increased obviously with 72 h depuration and especially with 20 % salinity fluctuation, concomitantly accompanying metabolism disorder. Furthermore, alterations in salinity and duration resulted in 381 different expression proteins (DEPs), which were gotten more involved in the pathways related to amino acid metabolism. Taken together, it was suggested that duration < 48 h and salinity fluctuations lower than 10 % were the preferred conditions for anhydrous living-preservation.

Fresh wet noodles (FWNs) are popular among people and have attracted increasing attention because of their characteristics of freshness, chewiness, good taste, and better maintenance of noodle flavor. However, due to the high moisture content and abundance of nutrients in FWN, they are prone to spoilage, which shortens their shelf life and reduces their quality, greatly restricting their large-scale production. Therefore, seeking effective preservation methods to prolong the shelf life is a major breakthrough for the industrialization of FWN. The present review provides a comprehensive overview of the main factors that contribute to the spoilage and degradation of FWN. These factors encompass microorganisms, moisture content, nutritional composition, enzymes, and storage temperature. Moreover, the recent developments in novel shelf-life extension technology applied to FWN, such as chemical preservatives, natural preservatives, physical treatment technologies, and composite preservation technology, are presented and discussed. From the literature reviewed, the application of technologies, such as adding preservatives, modified atmosphere packaging, microwave, cold plasma, ozone, and other technologies, has a certain effect on improving the shelf life of FWN, but the single preservation technology still has some deficiencies. In order to further improve the preservation efficiency, using two or more preservation methods is an important direction for future research on the preservation technology of FWN.

Here, we aimed to compare the effects of different preservation methods on outcomes of fecal microbiota. We evaluated the effects of different preservation methods using stool sample preservation experiments for up to 1 year. The stool samples from feces of healthy volunteers were grouped based on whether absolute ethanol was added and whether they were hypothermically preserved. Besides, we performed a systematic review to combine current fecal microbiota preservation evidence. We found that Proteobacteria changed significantly and Veillonellaceae decreased significantly in the 12th month in the room temperature + absolute ethanol group. The four cryopreservation groups have more similarities with fresh sample in the 12 months; however, different cryopreservation methods have different effects on several phyla, families, and genera. A systematic review showed that the Shannon diversity and Simpson index of samples stored in RNAlater for 1 month were not statistically significant compared with those stored immediately at -80°C (P = 0.220 and P = 0.123, respectively). The -80°C refrigerator and liquid nitrogen cryopreservation with 10% glycerine can both maintain stable microbiota of stool samples for long-term preservation. The addition of absolute ethanol to cryopreserved samples had no significant difference in the effect of preserving fecal microbial characteristics. Our study provides empirical insights into preservation details for future studies of the long-term preservation of fecal microbiota. Systematic review and meta-analysis found that the gut microbiota structure, composition, and diversity of samples preserved by storage methods, such as preservation solution, are relatively stable, which were suitable for short-term storage at room temperature. IMPORTANCE The study of gut bacteria has become increasingly popular, and fecal sample preservation methods and times need to be standardized. Here, we detail a 12-month study of fecal sample preservation, and our study provides an empirical reference about experimental details for long-term high-quality storage of fecal samples in the field of gut microbiology research. The results showed that the combination of -80°C/liquid nitrogen deep cryopreservation and 10% glycerol was the most effective method for the preservation of stool samples, which is suitable for long-term storage for at least 12 months. The addition of anhydrous ethanol to the deep cryopreserved samples did not make a significant difference in the preservation of fecal microbiological characteristics. Combined with the results of systematic reviews and meta-analyses, we believe that, when researchers preserve fecal specimens, it is essential to select the proper preservation method and time period in accordance with the goal of the study.

Sublethally injured state has been recognized as a survival strategy for microorganisms suffering from stressful environments. Injured cells fail to grow on selective media but can normally grow on nonselective media. Numerous microorganism species can form sublethal injury in various food matrices during processing and preservation with different techniques. Injury rate was commonly used to evaluate sublethal injury, but mathematical models for the quantification and interpretation of sublethally injured microbial cells still require further study. Injured cells can repair themselves and regain viability on selective media under favorable conditions when stress is removed. Conventional culture methods might underestimate microbial counts or present a false negative result due to the presence of injured cells. Although the structural and functional components may be affected, the injured cells pose a great threat to food safety. This work comprehensively reviewed the quantification, formation, detection, resuscitation and adaption of sublethally injured microbial cells. Food processing techniques, microbial species, strains and food matrix all significantly affect the formation of sublethally injured cells. Culture-based methods, molecular biological methods, fluorescent staining and infrared spectroscopy have been developed to detect the injured cells. Cell membrane is often repaired first during resuscitation of injured cells, meanwhile, temperature, pH, media and additives remarkably influence the resuscitation. The adaption of injured cells negatively affects the microbial inactivation during food processing.