Publications by authors named "Lei Rao"

Pepper seed protein isolate (PSPI) is a valuable plant-based protein source, yet the impact of processing methods such as high hydrostatic pressure (HHP) on its properties remains unclear. The impact of HHP on the structural and functional properties of PSPI at pH 7 and pH 9 was evaluated. Structural changes in PSPI were analyzed using spectral techniques, revealing significant alterations in the secondary and tertiary structures induced by HHP treatment.

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Developing highland barley products is complex, possibly due to the presence of β-glucan in highland barley. This study aims to investigate the impact of β-glucan on the physicochemical properties, microstructure, and molecular interactions of highland barley starch (HBS) during gelatinization and aging. Increasing the β-glucan content significantly reduced peak viscosity, setback viscosity, and breakdown viscosity, indicating altered gelatinization behavior.

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Sporulation as a typical bacterial differentiation process has been studied for decades. However, two crucial aspects of sporulation, (i) the energy sources supporting the process, and (ii) the maintenance of spore dormancy throughout sporulation, are scarcely explored. Here, we reported the crucial role of RocG-mediated glutamate catabolism in regulating mother cell lysis, a critical step for sporulation completion of Bacillus subtilis, likely by providing energy metabolite ATP.

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The clinical application of tumor necrosis factor-α (TNF-α) is limited by its short half-life, subeffective concentration in the targeted area and severe systemic toxicity. In this study, the recombinant polypeptide S4-TNF-α was constructed and coupled with chitosan-modified superparamagnetic iron oxide nanoparticles (S4-TNF-α-SPIONs) to achieve pH-sensitive controlled release and active tumor targeting activity. The isoelectric point (pI) of S4-TNF-α was reconstructed to approach the pH of the tumor microenvironment.

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Fermentation is a traditional method utilized for vegetable preservation, with microorganisms playing a crucial role in the process. Nowadays, traditional spontaneous fermentation methods are widely employed, which excessively depend on the microorganisms attached to the surface of raw materials, resulting in great difficulties in ideal control over the fermentation process. To achieve standardized production and improve product quality, it is essential to promote inoculated fermentation.

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Traditional unsupervised speech enhancement models often have problems such as non-aggregation of input feature information, which will introduce additional noise during training, thereby reducing the quality of the speech signal. In order to solve the above problems, this paper analyzed the impact of problems such as non-aggregation of input speech feature information on its performance. Moreover, this article introduced a temporal convolutional neural network and proposed a SASEGAN-TCN speech enhancement model, which captured local features information and aggregated global feature information to improve model effect and training stability.

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Considering the increasing severity of electromagnetic wave pollution, the development of high-performance low-filler-content microwave absorbers possessing wide frequency bands and strong absorption for practical applications is a demanding research hotspot. In this study, from the perspectives of the electromagnetic component coordination and structural design, a three-dimensional (3D) interconnected CoFeO/MXene-melamine foam (MF) was constructed via simple impregnation and a single freeze-drying step. By changing the absorber (CoFeO/MXene) concentration, the pore opening and electromagnetic properties of the 3D foams can be effectively adjusted.

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Introduction: Quercetin has an ideal therapeutic effect on islet function improvement in type 2 diabetes mellitus (T2DM). However, the therapeutic benefit of quercetin is hindered by its poor bioavailability and limited concentration in pancreatic islets. In this study, superparamagnetic iron oxide nanoparticle (SPION)-modified exosomes were prepared to load quercetin, hoping to endow quercetin with enhanced water solubility and active targeting capacity with the help of magnetic force (MF).

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Native starches usually have poor polyphenol-binding efficiency despite remarkable architectural structures. In this study, the interaction between cyandin-3-O-glucose (C3G) and three starches under high hydrostatic pressure was investigated. Pressure (200-550 MPa) was found to promote the binding rate of potato starch from 31.

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This study aimed to analyze and reduce the pressure resistance (PR), sublethal injury (SLI), and viable but non-culturable (VBNC) populations during HPP. Escherichia coli, Staphylococcus aureus, Bacillus amyloliquefaciens and Lactiplantibacillus plantarum were selected for evaluation of PR, SLI and VBNC cell counts and proportions during HPP. The results revealed that the bactericidal efficiency against these strains gradually improved as the processing pressure increased.

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In this study, the cyanidin-3-O-glucoside (C3G)-binding capacities of three native starches were investigated. While potato starch had the largest binding capacity of 0.34 mg/100 mg, corn and pea starch had binding capacities of 0.

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The effects of high pressure homogenization (HPH) at different pressures (50, 100, 150 and 200 MPa) and temperatures (4, 20, 40, 60 and 80 °C) on the interaction between corn starch (CS) and cyanidin-3-O-glucoside (C3G) were investigated. Based on analyses of zeta potential, attenuated total reflection-flourier transformed infrared spectroscopy and binding rate after adding shielding agents, the main interaction force changed from electrostatic interaction to hydrogen bonds. In comparison, the interaction between CS and C3G exhibited greater strength at low temperatures and pressures.

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Introduction: Entry into the viable but nonculturable (VBNC) state is a survival strategy adopted by bacteria to survive harsh environment. Although VBNC cells still have metabolic activity, they lose the ability to form colonies on nonselective culture media. Thus, conventional bacterial detection methods, such as plate counting, are unable to detect the presence of VBNC cells.

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More than 20 million tons of ladle furnace slag are produced annually. This slag is mainly treated by stockpiling; however, stacking results in dust and heavy metal pollution. Utilizing this slag as a resource can reduce primary resource consumption and eliminate pollution.

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The steadily increasing use of microwave stealth materials in aerospace flying vehicles needs the development of lightweight absorbers with low density and high thermal stability for printing or spraying. In that regard, the structural designability of typical microwave absorbers made of FeO seems to be a significant roadmap. In this work, a hollow spherical structure with a uniform carbon shell around the urchin-like FeO core (FeO@C) was produced via a two-step hydrothermal method and annealing.

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Bacterial spores are highly resilient and universally present on earth and can irreversibly enter the food chain to cause food spoilage or foodborne illness once revived to resume vegetative growth. Traditionally, extensive thermal processing has been employed to efficiently kill spores; however, the relatively high thermal load adversely affects food quality attributes. In recent years, the germination-inactivation strategy has been developed to mildly kill spores based on the circumstance that germination can decrease spore-resilient properties.

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As a novel non-thermal pasteurization technology, high pressure carbon dioxide (HPCD) has been used in food processing. However, it could induce microorganisms into a viable but nonculturable (VBNC) state, posing a potential risk to food safety and public health. In this study, we attempted to investigate the effect of various preliminary stresses including cold, heat, osmosis, acidity and oxidation on HPCD-induced VBNC formation.

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As a non-thermal technology, high hydrostatic pressure (HHP) has been widely investigated for inactivating microorganisms in food. Few studies have been presented on the pressurization/depressurization rate and mode of microbial inactivation. In this study, effect of pressurization rate and mode on and cell damage during HHP treatment was investigated.

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For the better standardization and widespread application of the determination method of carotenoids in both chili peppers and their products, this work reports for the first time the simultaneous determination of five main carotenoids, including capsanthin, zeaxanthin, lutein, β-cryptoxanthin and β-carotene in chili peppers and their products, with optimized extraction and the high-performance liquid chromatography (HPLC) method. All parameters in the methodological evaluation were found to be in good stability, recovery and accuracy compliance with the reference values; the coefficients for the calibration curves were more than 0.998; and the LODs and LOQs varied from 0.

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Under stressful conditions, bacteria can enter viable but non-culturable (VBNC) state to survive. VBNC cells lost ability to grow on routine culture medium but are still alive and may revive in suitable conditions. The revived cells can consume nutrients or produce toxins, leading to food spoilage or human illness, posing great risk to food safety and public health.

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Bacterial spores can preserve cellular dormancy for years, but still hold the remarkable ability to revive and recommence life. This cellular awakening begins with a rapid and irreversible event termed germination; however, the metabolic determinants required for its success have been hardly explored. Here, we show that at the onset of the process of sporulation, the metabolic enzyme RocG catabolizes glutamate, facilitating ATP production in the spore progenitor cell, and subsequently influencing the eventual spore ATP reservoir.

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During the pandemic of coronavirus disease 2019, the fact that frozen foods can carry the relevant virus raises concerns about the microbial safety of cold-chain foods. As a non-thermal processing technology, high pressure carbon dioxide (HPCD) is a potential method to reduce microbial load on cold-chain foods. In this study, we explored the microbial inactivation of low temperature (5-10 °C) HPCD (LT-HPCD) and evaluated its effect on the quality of prawn during freeze-chilled and frozen storage.

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In this study, composite pear juice was processed by ultra-high pressure homogenization (UHPH) at four different pressures (50, 100, 150, and 200 MPa) with six different temperatures (4, 20, 30, 40, 60, and 80°C), then microorganism and physicochemical and nutritional properties of the samples were investigated. The counts of total aerobic bacteria (TAB) and yeasts and molds (Y&M) were reduced by 0.89-4.

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Proteins are important food ingredients that possess both functional and nutritional properties. High hydrostatic pressure (HHP) is an emerging nonthermal food processing technology that has been subject to great advancements in the last two decades. It is well established that pressure can induce changes in protein folding and oligomerization, and consequently, HHP has the potential to modify the desired protein properties.

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