To investigate the effects of ultrasonic treatment on lotus root juice quality, ultrasonic pretreatment was applied under varying conditions: frequencies (25, 33, 40, 59 kHz), power levels (40%, 60%, 80%, 100%), and treatment durations (0, 15, 30, 45, 60 min). Based on six nutritional quality indicators: soluble quinones, protein, vitamin C, color, soluble solids, and pH, along with four browning-related quality parameters: total phenolic content, browning degree, polyphenol oxidase (PPO) activity, and peroxidase (POD) activity, combined with principal component analysis and correlation analysis, to identify ultrasonic processing parameters that effectively enhance the comprehensive quality and sensory characteristics of lotus root juice. Finally, an electronic tongue analysis was conducted to evaluate the degree of flavor change in lotus root juice before and after ultrasonic treatment. Results indicated that moderate ultrasonic treatment improved lotus root juice quality. The optimal ultrasonic processing parameters identified were 30 min duration, 60% power, and 40 kHz frequency. Under these conditions, lotus root juice browning decreased by 28.13%, PPO and POD activities decreased by 66.67% and 62.07% respectively, while polyphenol and protein contents increased. Simultaneously, ultrasonic treatment reduced bitterness and enhanced acidity in the juice. These findings provide a foundation and theoretical basis for the development of lotus root products.

This study aimed to investigate the structural changes of rice bran protein during gastrointestinal digestion and the immunomodulatory activity of its digestive products. Rice bran protein (RBP) was used as the raw material. Changes in molecular weight, microstructure, and amino acid composition were analyzed at different stages of in vitro simulated gastrointestinal digestion. The immunomodulatory activity of RBP digestion products (RBPI) was evaluated using RAW264.7 murine macrophage cells as a model. Most of the digestive products exhibited a molecular weight below 10 kDa after simulated gastrointestinal digestion. The β-sheet content increased from 33.66% to 46.50%, while the α-helix content decreased from 22.38% to 15.80%. Essential amino acids (EAA) accounted for 40.33% of the total amino acid content, with an EAA to non-essential amino acid (NEAA) ratio of 0.68. Digestion changed the microstructural of the protein, and the surface of the digestive products appeared finely granular. RBPI, at concentrations of 50~600 μg/mL, significantly enhanced the viability of RAW264.7 cells and notably increased their phagocytic capacity and nitric oxide production. Furthermore, RBPI significantly stimulated the secretion of the cytokines interleukin (IL)-1β, IL-10, and tumor necrosis factor-α (TNF-α) by macrophages, indicating strong immunoenhancing activity. These findings indicated that RBP, after in vitro simulated digestion, had good nutritional value and potential to activate macrophages and boost immune function, it was expected to provide data support for the application of gastrointestinal digestion products of rice bran protein in the functional food and health food industries.

The physicochemical properties, physical and oxidative stability of whole fruit oil body (WOB), peel oil body (POB), and seed oil body (SOB) via water extraction were investigated in this study. The results showed that SOB had significantly higher contents of total sugar (49.58±0.30 g/kg), protein (12.00%±0.37%), essential amino acids (41.99±0.23 mg/100 g protein), and total amino acids (103.25±0.38 mg/100 g protein) than WOB and POB (P<0.05). In contrast, WOB exhibited the highest total phenol content (2.59±0.02 mg/g), compared with POB (P<0.05). POB had the highest lipid content (92.88%±1.70%), and significantly higher than WOB and SOB (P<0.05). Additionally, the apparent viscosity of three oil body emulsions decreased with the increase of shear rate and showed the shear-thinning behavior. At the same shear rate, SOB had higher apparent viscosity, storage modulus (G'), and loss modulus (G'') than WOB and POB. SOB also had significantly lower particle size, lipid hydroperoxide (LPO), and thiobarbituric acid reactive substance (TBARS) values than WOB and POB, whereas SOB exhibited higher absolute zeta-potential and interfacial protein adsorption rate than WOB and POB (P<0.05). Principal component analysis confirmed that SOB had the highest comprehensive score. Therefore, SOB extracted from Idesia polycarpa Maxim seed, demonstrated the superior physicochemical properties and stability. The research would provide the essential technical support for the processing and utilization of Idesia polycarpa Maxim oil body.

This study aimed to immobilize D-allulose 3-epimerase from Ruminococcus sp. (RDAE) using cross-linked enzyme aggregates (CLEAs) technology. The immobilized enzyme (RDAE-CLEA) was prepared by optimizing the precipitant polyethylene glycol (PEG4000) concentration, cross-linker dextran aldehyde concentration, and cross-linking time. The enzymatic properties of the free enzyme (RDAE) and the immobilized enzyme (RDAE-CLEAs) were comparatively evaluated. Furthermore, the structural changes in RDAE before and after immobilization were analyzed using scanning electron microscopy, infrared spectroscopy, and molecular dynamics simulations. In the absence of stabilizers, the RDAE-CLEAs prepared with 36% (w/v) PEG4000 and 2.73 mg/mL dextran aldehyde at 4 h achieved an enzyme activity recovery rate of 55.88%. Compared with the free enzyme, the immobilized enzyme exhibited siginificantly improved environmental tolerance (P<0.05) at pH6.0~7.5 and 30~55 ℃, retaining 59.77% initial activity after 10 reuse cycles. Structural analysis revealed that RDAE underwent significant conformational changes during cross-linking, and the binding tightness between subunits in the enzyme tetramer was reduced. The study developed RDAE-CLEAs with good reusability and elucidated the dual role of surface lysine residues in both facilitating covalent cross-linking and maintaining the rigidity of the tetrameric structure of RDAE. Considering the critical impact of tetramer rigidity on the thermal stability of RDAE, developing novel cross-linking strategies that preserve lysine residues on the enzyme surface would substantially improve the application potential of RDAE-CLEAs.

This study investigated the antibacterial components and underlying mechanisms of action of gallic (Galla chinensis) extracts. The ethanol extract was separated into different fractionations by using silica gel column chromatography, followed by analysis via ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS). The mechanism underlying the inhibitory effect of gallic extract on Penicillium citrinum was elucidated by assessing of cell membrane integrity, oxidative stress, mitochondrial function, and cellular ultrastructure. The results demonstrated that the Fr.3 fraction exhibited an maximum inhibition zone against P. citrinum with the diameter of 17.85 mm. UPLC-QTOF MS analysis identified 12 bioactive compounds in Fr.3, including ellagic acid, gallic acid, and (-)-epigallocatechin, among others. Antifungal assays demonstrated that gallic acid and (-)-epigallocatechin inhibited P. citrinum growth by 53.99% and 45.75%, respectively, after 6 days of culture at 28 ℃. Gallic acid impaired cell membrane integrity, leading to a 78.80% increase in relative conductivity and a 60.16% increase in malondialdehyde content. Gallica acid also induced oxidative stress, resulting in elevated reactive oxygen species (ROS) levels, which subsequently disrupted intracellular redox homeostasis in P. citrinum cells. Additionally, gallic acid inhibited mitochondrial function of P. citrinum, resulting in a 76.88% decrease in ATPase activity, a decline in mitochondrial membrane potential, with depolarization increased to 17.31-fold of the control. Furthermore, the P. citrinum cell ultrastructure was compromised and plasmolysis was observed. These findings elucidate the multitarget inhibitory mechanism of G. chinensis at the molecular level and provide a theoretical framework for natural antifungal agent development.

In this study, PacBio SMRT sequencing technology and conventional physicochemical analysis methods were employed to conduct a comparative analysis of the fungal community structure and physicochemical characteristics of medium-temperature Daqu samples from Luzhou and Nanyang regions. Furthermore, principal coordinate analysis (PCoA) and correlation analysis were performed to reveal the association between dominant fungal species and physicochemical properties. The results of fungal community analysis showed that the fungal communities in medium-temperature Daqu from both Luzhou and Nanyang regions were dominated by Thermoascus aurantiacus, Thermomyces lanuginosus, and Saccharomycopsis fibuligera, with cumulative average relative abundances of 64.59% and 83.58%, respectively. Additionally, Rasamsonia composticola and Issatchenkia orientalis were identified as fungal biomarkers for medium-temperature Daqu from Luzhou and Nanyang regions, respectively. Physicochemical analysis results indicated that, compared to medium-temperature Daqu from Nanyang, Daqu from Luzhou exhibited significantly higher water activity, moisture content, bound water content, ash content, starch content, amino acid nitrogen content, and protein content (P<0.05), while density, crust hardness, free water content, liquefaction power, esterification power, and saccharification power were significantly lower (P<0.05). Correlation analysis revealed complex relationships between dominant fungal species and physicochemical indicators in medium-temperature Daqu. This study provides important supporting data for understanding the differences in fungal communities and physicochemical properties of medium-temperature Daqu across different regions.

The aim of this study was to elucidate the antibacterial mechanism of Zanthoxylum bungeanum extract against Shewanella putrefaciens. The effects of the extract on bacterial growth, cell wall integrity, membrane permeability, cellular morphology, and transcriptional processes were investigated using growth curve analysis, extracellular alkaline phosphatase (AKP) and protein leakage assays, transmission electron microscopy, DNA-binding analysis, and transcriptomics. The results demonstrated that Zanthoxylum bungeanum extract significantly inhibited Shewanella putrefaciens growth in a concentration-dependent manner. It disrupted the integrity of the cell wall and membrane permeability, leading to the leakage of AKP and intracellular proteins. Additionally, the extract interacted with Shewanella putrefaciens genomic DNA, altering metabolic pathways, signal transduction, and motility-related gene expression. Transcriptome analysis identified 301 differentially expressed genes, with the flagellar assembly pathway exhibiting the most significant enrichment (P<0.05). These findings indicated that Zanthoxylum bungeanum extract exerted its antibacterial effects through multifaceted mechanisms, including growth suppression, structural damage to the cell wall and membrane, morphological deformation, and transcriptional modulation. Therefore, it is a promising natural resource for developing antibacterial agents.

In order to screen mold starters that could provide desirable flavor for mold-ripened cheeses, the mold strains isolated from sufu-related products were used to prepare experimental cheese samples. These samples were subjected to the determination of physicochemical indicators and sensory evaluation, ultimately identifying strains that exhibited both cheese-ripening abilities and favorable flavor profiles. The 4 mold strains with cheese-making potential were isolated from sufu-related products, namely Geotrichum candidum (strains MP07 and MP08), Mucor circinelloides (strain FR04), and Actinomucor elegans (strain QF03). Physicochemical indicators demonstrated that all 4 sufu-derived mold strains exhibited certain cheese-ripening abilities. The cheeses produced by them were close to commercial Camembert cheese in terms of main component content. The moisture content was 51.43~54.46 g/100 g, the protein content was 15.00~16.31 g/100 g, and the fat content was 26.47~29.62 g/100 g. At the end of ripening, the pH inside the cheeses produced by them was around 6.0, and the pH outside was around 7.0. Primary and secondary proteolysis occurred in the cheeses produced by them, and the proteolysis indices of sample 423 produced by strain FR04 and sample 365 produced by strain QF03 were significantly higher than those of the other 2 groups of samples (P<0.05), with 12.55% and 11.59%, respectively, which indicated that these 2 strains had stronger cheese-ripening abilities. The texture parameters of the core parts of the cheeses produced by them changed during the ripening periods. The hardness, chewiness and resilience of sample 365 at the end of ripening were significantly lower than those of the other 3 groups (P<0.05), indicating that the internal ripening state was the best. The results of sensory evaluation indicated that there were significant differences (P<0.05) in appearance, odor, taste, and mouthfeel between the 4 groups of sufu-derived mold-ripened cheeses and commercial Camembert cheese, and the sample 365 achieved the highest average overall liking scores (5 points) among the five groups of mold-ripened cheeses. Therefore, among the 4 mold strains, strain QF03 was determined to be the most suitable strain for cheese production. This study provides a new high-quality fermentation strain to produce mold cheeses, which contributes to the development and utilization of microbial resources in China.

This study aimed to screen a strain with high cholesterol-lowering effect from traditional fermented yak yogurt in western Sichuan province and explore its therapeutic effect on hypercholesterolemia. This study focused on 295 strains of lactic acid bacteria isolated from traditional fermented yak yogurt in Western Sichuan, and the lactic acid bacteria with high cholesterol-lowering ability were screened by ferric ammonium sulfate method and o-phthalaldehyde method, and the in vitro probiotic characterization test and safety evaluation were carried out, and the cholesterol-lowering effect of the strains was evaluated by establishing a mouse model of hypercholesterolemia induced by high-fat diet. The screening revealed four strains exhibiting favorable cholesterol-reducing efficiency and efficacy isolated from 295 lactic acid bacteria. Among the 4 strains, strain 166 had the highest survival rate in simulated gastric fluid tolerance assay test, and the number of viable bacteria remained above 5.3×10⁸ CFU/mL after 3 h of incubation in the simulated intestinal fluid, and it possessed a good bile salt tolerance performance, with a hydrophobic capacity of up to 62.3%, auto-aggregation capacity of 18.65%, which was identified as Limosilactobacillus fermentum. In addition, strain 166 was evaluated negatively for harmful metabolites, no hemolysis phenomenon, no gelatin liquefaction, and showed some resistance to eight antibiotics, which showed good in vitro probiotic properties and safety. In vivo experiments in animals showed that Limosilactobacillus fermentum 166 could significantly reduce the serum total cholesterol, triglycerides, low-density lipoprotein cholesterol levels and atherosclerosis index of mice, effectively increase the content of serum high-density lipoprotein cholesterol, and effectively improve the Lee's index, liver index, perirenal fat index and abdominal fat index. Therefore, Limosilactobacillus fermentum 166 has the potential to be developed as a functional probiotic product, providing data support for the prevention and adjunctive therapy of hypercholesterolemia.

This study was aimed to extract the total flavonoids from the flowers of Abelmoschus manihot (L.) Medicus, clarify the composition of the individual flavonoid compounds as well as its ameliorative effect on hyperuricemia in mice. The dried flower of Abelmoschus manihot (L.) Medicus was used as raw materials for this study. Both single-factor and response surface approaches were performed to optimize the parameters for the isolation of total flavonoid from Abelmoschus manihot (L.) Medicus. The molecular composition of Abelmoschus manihot (L.) Medicus extract was analyzed using the targeted metabolomics approach. Furthermore, an animal model of hyperuricemia was established to elucidate the hypouricemic activity of total flavonoid. The maximum content of total flavonoid could reach 19.73±0.11 mg/g when the extraction lasting for 35 min under the conditions set at a liquid/material ratio 25:1 mL/g, ultrasonic power 250 W and microwave power 190 W. The targeted metabolomics data revealed that the dominant flavonoid compounds were myricetin, phenylalanine, rutin, quercetin 3-glucoside, quercetin, etc. Compared to the level of uric acid (124.95±26.22 μmol/L) in the hyperuricemic mice, the administration with low- and high-dose of total flavonoid extract significantly decreased the uric acid levels, being 52.62±2.76 μmol/L and 43.80±9.94 μmol/L, respectively. The findings indicated that total flavonoid extract could exert hypouricemic effects by alleviating kidney and liver damage in mice, lowering levels of interleukin-1β, interleukin-6, tumor necrosis factor, creatinine and urinary nitrogen in the serum, malondialdehyde content in the kidney, and xanthine oxidase activity in the liver, while enhancing the activity of superoxide dismutase and catalase in the kidney. These findings are expected to provide theoretical guidance and data support for the value-added utilization of Abelmoschus manihot (L.) Medicus and also for the development of novel hypouricemic products.