The combination of Nisin with active substances can broaden its antibacterial spectrum and endow the system with antioxidant capacity, thereby synergistically enhancing food preservation efficacy. Consequently, it attracted much attention in the field of food safety research. In particular, the construction of composite films using Nisin-based compounds as functional components through different film-forming methods (such as coating, casting, extrusion, and electrospinning, etc.) became a research hotspot in the field of food active packaging in recent years. This article begins with a brief introduction to Nisin and its antibacterial mechanism, followed by a comprehensive overview of the bioactive substances utilized in conjunction with Nisin and their synergistic effects. Then, the research progress of Nisin compounds active films in food preservation, specifically from the aspects of different film-forming techniques, is mainly reviewed. Furthermore, the limitations of the current research and the future development directions are summarized and discussed, with the expectation of providing a reference for the efficient application of Nisin in the field of food preservation.

In recent years, with the popularization of the concept of healthy diet, foods with glycemic index (GI) less than or equal to 55 (low GI) have gradually become the focus of consumers' attention. Among them, low GI noodles is a staple food that can regulate the level of blood sugar after meals, which have the advantages of reducing post-meal blood sugar fluctuations, preventing cardiovascular disease, regulating insulin levels, and enhancing satiety. In this manuscript, the research status of low GI noodles in recent years are summarized. The concept, classification, measurement method and influencing factors of GI are briefly described firstly, and then the influence mechanism of different types of raw materials, raw and auxiliary materials and different processing methods on the texture characteristics, sensory evaluation and starch content of low GI noodles are discussed, mainly focuses on the effects of different types of products on the level of postprandial blood glucose. Finally, the development prospect of low GI noodles is anticipated, in order to provide a theoretical basis for future research and market application in this field.

Peptidoglycan (PG) is a class of microbial polysaccharides with the functions of immunomodulation, anti-tumor, anti-inflammation, adsorption and toxicity reduction, which mainly exists in the bacterial cell wall. Due to its unique biological functions and structural properties, it has attracted much attention in scientific research and practical applications, and is now widely used in many fields such as medical, aquatic, and food. This paper summarizes the research progress of peptidoglycan in terms of its structure, biosynthetic pathway, extraction, function and application. In terms of extraction, the traditional physical and chemical methods, enzyme digestion and the emerging combined extraction method are described, and the advantages and disadvantages of each method are analyzed. The potential link between the biological functions of peptidoglycan and bacterial pathogenicity and immunomodulation is explored in depth. The results and challenges in practical applications are discussed, and the broad prospects of peptidoglycan research in multiple fields are envisioned for the future. By reviewing the current status of peptidoglycan research from multiple perspectives, it provides a reference for the subsequent in-depth study of its properties and the expansion of its applications.

Exploring the xanthine oxidase (XOD) inhibitory peptide from Chlorella pyrenoidosa could provide a scientific basis for hyperuricemia prevention and treatment strategies, and promote the comprehensive utilization of microalgal protein resources. In this study, Chlorella pyrenoidosa was used as the raw material to extract proteins. With the XOD inhibition rate and the degree of hydrolysis (DH) as evaluation indicators, the optimal enzymatic hydrolysis conditions were optimized through single-factor and response surface experiments. Based on this, further analysis of XOD inhibitory peptide was conducted. The results showed that papain was the most suitable protease, and the optimal enzymatic hydrolysis conditions were pH7.0, hydrolysis temperature 48.0 ℃, hydrolysis time 4.0 h, enzyme dosage 2000 U/g, and substrate concentration 10 mg/mL. Under these conditions, the theoretical inhibition rate was 73.78%, and the actual inhibition rate reached 71.56%±0.51%. The amino acid composition of Chlorella pyrenoidosa XOD inhibitory peptide was reasonable, with essential amino acids, hydrophobic amino acids, and basic amino acids accounting for 43.17%, 45.07%, and 14.15% of the total, respectively. Additionally, they exhibited moderate stability under gastrointestinal digestion conditions, but their inhibitory activity decreased significantly under high temperature or strong acid/alkaline conditions. They were also relatively sensitive to metal ions such as Fe²⁺, Fe³⁺, Cu²⁺ and Mg²⁺. The relative molecular mass mainly concentrated below 1 kDa, and the ultrafiltered fraction with a molecular weight <3 kDa showed the highest XOD inhibitory activity, with an IC₅₀ of (5.23±0.68) mg/mL. This study provides a theoretical reference for the development and utilization of food-derived uric acid-lowering peptides.

This study aimed to investigate the inhibitory effect and underlying mechanism of ethanol extract from Chrysanthemum morifolium. 'Boju' (CME) on atherosclerosis (AS). An AS model was established using ApoE⁻/⁻ mice, which were randomly divided into a model group, low-, medium-, and high-dose CME groups (50, 100, and 200 mg/kg), a positive control group (simvastatin 3 mg/kg), and a normal control group, with an intervention period of 12 weeks. The levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in serum, and the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β in serum were measured. Pathological changes were observed via Oil Red O staining of the aorta and hematoxylin-eosin (H&E) staining of the liver. The expressions of LXRα and ABCA1 in liver tissue and NF-κB p65 in the aorta were detected by qRT-PCR and Western blot. In in vitro experiments, a foam cell model was established by inducing RAW264.7 macrophages with ox-LDL, and the cells were divided into a control group, a model group, and low-, medium-, and high-dose CME groups (25, 50, and 100 μg/mL). Cell viability, foam cell rate, intracellular contents of TC, cholesteryl ester (CE), and free cholesterol (FC), as well as the expressions of genes and proteins related to relevant signaling pathways were detected. Additionally, the NF-κB inhibitor BAY11-7082 was used to verify the mechanism. The results showed that compared with the model group, CME significantly decreased the serum levels of TC, TG, and LDL-C, and increased the serum level of HDL-C (P<0.01). Pathological staining demonstrated that the low-, medium-, and high-dose CME groups could reduce aortic lipid deposition and hepatic steatosis in a dose-dependent manner. Furthermore, CME significantly upregulated the mRNA and protein expressions of LXRα and ABCA1 in liver tissue (P<0.01), with the protein level of LXRα upregulated from 0.31±0.04 in the model group to 0.91±0.06 in the high-dose CME group. In addition, CME reduced the protein expression of p-NF-κB p65 in the aorta and the serum levels of TNF-α, IL-6, and IL-1β (P<0.01), and the protein level of p-NF-κB p65 decreased from 1.85±0.18 in the model group to 0.92±0.11 in the high-dose CME group. Meanwhile, CME decreased the intracellular contents of TC and CE and the CE/TC ratio in RAW264.7 macrophages, thereby inhibiting foam cell formation. Moreover, it upregulated the expressions of PPARγ, LXRα, and ABCA1 and inhibited the activation of the NF-κB pathway, and no significant differences were observed in key indicators such as p-NF-κB p65, ABCA1, TC, CE, and CE/TC ratio between the high-dose CME group and the BAY11-7082 inhibitor group. These results indicated that AS could be significantly inhibited by CME through activating the LXRα/ABCA1 pathway to regulate cholesterol metabolism and inhibiting the NF-κB pathway to alleviate inflammatory responses.

To explore the effects of different pretreatment methods on the structure and physicochemical properties of soluble dietary fiber (SDF) from millet bran and to achieve its high-value utilization. This study used millet bran as the raw material and SDF yield as the indicator. Single-factor and orthogonal experiments were employed to determine the optimal pretreatment conditions for the different pretreatment methods (ultrasound, superfine grinding, and ultrasound-superfine grinding combination). The effects of different treatment methods on the structure and physicochemical characteristics of millet bran SDF were analyzed by measuring indicators such as monosaccharide composition, molecular weight distribution, infrared spectra, internal particle structure, micro-morphology, thermogravimetric, water holding capacity, oil holding capacity, swelling capacity, and solubility. The results showed that under the conditions of grinding particle size of 800 mesh, solid-liquid ratio of 1:40 (g/mL), ultrasonic power of 330 W, and ultrasonic time of 50 min, the highest SDF yield of millet bran reached 20.44%±0.17%, representing a 2.68-fold increase in yield. Compared with conventional grinding, ultrasound, and superfine grinding, their combination altered the relative content of monosaccharide components in millet bran SDF. The combination of both methods increased the proportion of high molecular weight components to 45.42%, forming a loose and porous structure on the crystal surface, and had the most obvious effect on reducing its orderliness and thermal stability. Meanwhile, analysis of physicochemical characteristics indicated that the ultrasound-superfine grinding combination significantly improved the water-holding capacity, oil-holding capacity, swelling capacity, and solubility of millet bran SDF (P<0.05). Therefore, the combined treatment of ultrasound and superfine grinding enhances the physicochemical characteristics by improving its structure, thereby improving the processing performance and increasing the potential utilization value of millet bran SDF.

This study aimed to extract the active substance from Laminaria japonica (L. japonica) and evaluate their composition and hypolipidemic activity. The alcohol extract of L. japonica (LJA), water extract of L. japonica (LJW), enzymic hydrolysates of L. japonica (LJE) and dietary fiber extract of L. japonica (LJDF) were prepared by using different polar solvents combined with ultrasound-assisted alcohol extraction, water extraction, complex proteolytic enzymes and sodium carbonate acid, and their composition was analyzed. The above four active substances were mixed to obtain the total active substances of L. japonica (LJM). This study adopted C. elegans as a model organism to investigate the effects of bioactive compounds derived from L. japonica on lipid metabolism-related biochemical parameters and Messenger RNA (mRNA) transcription levels. The result revealed that the main components of LJA included choline, phospholipids, pyrimidines, terpenoids, arachidonic acid, steroids, polyphenols and disaccharides; LJW mainly consisted of two polysaccharides with molecular weights of 368.0 kDa and 1.0 kDa, with monosaccharide composition of glucose, galactose, fucose, mannose and arabinose; LJE mainly consisted of protein active peptides, containing six proteins (YP_006639117.1, AIW62928.1, WDS74817.1, WDS74887.1, QBF51285.1 and ABB80121.1), 43 peptides; LJDF mainly consisted of two polysaccharides with molecular weights of 717.073 kDa and 11.502 kDa, with monosaccharide composition of mannose aldehyde, gulonose aldehyde, galactose and fucose. The result of C. elegans experiments demonstrated that the L. japonica active substances significantly reduced triglyceride (TG) and malondialdehyde (MDA) levels (P<0.01). Meanwhile, these substances also increased total superoxide dismutase (T-SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) levels (P<0.01). At the mRNA transcription level, the L. japonica active substances significantly upregulated genes NHR-49, FAT-5, FAT-6, FAT-7, DAF-2, and DAF-16 (P<0.01). Conversely, the substances significantly downregulated genes MOD-1, ACS-2, and AGE-1 (P<0.01). This suggested that the L. japonica active substances improved C. elegans lipid peroxidation and reducing lipid accumulation in C. elegans through regulating fatty acid β-oxidation (NHR-49, MOD-1 and ACS-2), fatty acid synthesis (FAT-5, FAT-6 and FAT-7) and insulin (DAF-2, AGE-1, DAF-16) signaling pathways.

In this study, lard, whey protein, sucrose fatty acid ester, and glucose syrup were employed as raw materials to optimize the preparation of powdered fat through orthogonal experimental design, with encapsulation efficiency as the evaluation index. The effect of powdered fat on the physicochemical properties of dumpling wrappers were systematically investigated. The results demonstrated that the powdered fat prepared under optimized conditions exhibited an embedding rate of 85.36% with uniform particle distribution. The incorporation of powdered fat gradually reduced the hardness and tensile strength of the dumpling wrappers, while the tensile distance reached a maximum value of 135.51 mm at a 4% addition level. According to the rheological study, the dumpling wrappers' energy storage modulus and loss modulus peaked at 4% powdered fat (87314 Pa and 46281 Pa, respectively). The incorporation of powdered fat initially reduced moisture mobility in dumpling wrappers, followed by a subsequent increase. Scanning electron microscopy (SEM) revealed that at a 4% powdered fat concentration, the dumpling wrappers formed a compact and continuous gluten network structure. However, this structural integrity was compromised at higher concentrations. Therefore, an appropriate addition of powdered fat can enhance the sensory qualities of dumpling wrappers while stabilizing the gluten network. These results provide a theoretical basis for improving dumpling wrappers quality.

In order to investigate the effects of pre-harvest salicylic acid (SA) spraying on post-harvest quality and antioxidant metabolism of prunes (Prunus domestica L.), 'French' prune trees in Xinjiang were treated with SA solutions at concentrations of 1, 2, or 4 mmol/L. Applications were made during four key developmental stages: fruit set, expansion, color change, and maturity. A control group received water sprays. Following harvest, fruit were stored at 1.0±1.0 ℃ and 90%~95% relative humidity. Quality parameters and antioxidant metabolism indicators were assessed at 15 days intervals over the 90 days storage period. Results demonstrated that pre-harvest spraying of SA could significantly maintain the hardness, soluble solids content and titratable acid level of plum fruits during post-harvest storage, and inhibit the color blackening, respiration and weight loss rate of fruits. The 2 mmol/L SA treatment proved most effective. At the end of storage, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR) in the 2 mmol/L SA-treated prunes were 1.17, 1.40, 1.54, 1.23, and 1.26 fold those of the control group, respectively (P<0.05). The contents of ascorbic acid (AsA) and glutathione (GSH) were 2.70 and 1.08 fold those of the control group, enhancing the antioxidant enzyme activities and effectively maintaining AsA and GSH levels. Additionally, the production rate of superoxide anion (O₂⁻·), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) accumulation, as well as cell membrane permeability, were suppressed. This indicated that spraying SA before harvest could maintain the post-harvest quality of prunes by enhancing their antioxidant metabolism capacity.

Sweet cherries are susceptible to quality deterioration during postharvest storage and transportation, including flesh softening and spoilage, which greatly reduce their commercial value. In order to preserve postharvest quality and extend the shelf life of the fruit, this study utilized 'Samituo' sweet cherries as the experimental material to investigate the effects of pre-harvest spraying with alginate oligosaccharides at concentrations of 50, 100, and 200 mg/L on fruit quality-related parameters and the activities of cell wall degrading enzymes during low-temperature storage. The results indicated that the pre-harvest application of alginate oligosaccharides at various concentrations effectively delayed the decline in soluble solids content, titratable acidity, and fruit firmness, while also reducing the rate of fruit weight loss, as compared to the control group. Treatment with alginate oligosaccharides delayed the decline of L^*, a^*, and b^* values and color saturation, while also inhibiting the activities of pectate lyase, pectin methylesterase, polygalacturonase, cellulase, β-galactosidase, β-glucosidase, pectin methylesterase and polygalacturonic acid transeliminase. Among the treatments, 200 mg/L alginate oligosaccharides exhibited the most pronounced effect. The correlation analysis reveals that titratable acidity was significantly and positively correlated with the activities of β-galactosidase and pectin methylesterase, while was distinctly negatively correlated with the activities of polygalacturonase and cellulase. In contrast, soluble solids content exhibited a significant negative correlation with polygalacturonase, cellulase, polygalacturonic acid transeliminase, pectate lyase, and β-galactosidase activities. Furthermore, fruit hardness showed a significant negative correlation with the activities of polygalacturonase, cellulase, pectate lyase, and β-glucosidase. Weight loss was significantly positively correlated with polygalacturonase and cellulase activities, whereas it was significantly negatively correlated with the activities of polygalacturonic acid transeliminase, pectin methylesterase, pectate lyase, β-glucosidase, β-galactosidase, and pectin methylesterase. These findings suggest that pre-harvest application of alginate oligosaccharides can delay fruit softening and maintain storage quality by suppressing the activity of enzymes related to fruit cell wall degradation.