BACKGROUND:Diabetic kidney disease (DKD) is the commonest cause of end-stage kidney disease. Supplementation of dietary fiber may have potential benefits for patients with DKD. OBJECTIVES:This study developed a type of functional extruded rice (FER) with rice starch and 10% inulin using twin-screw extrusion, and its beneficial effects on DKD mice were evaluated. METHODS:Mice were divided into control (CON) group (diabetes heterozygous mice fed a normal diet containing extruded rice starch without inulin), model (MOD) group [diabetic MOD, diabetes homozygous mice (db/db) mice fed a normal diet containing extruded rice starch without inulin], FER-fed (RERF) group (db/db mice fed a normal diet containing FER), and metformin-treated group (positive CON, db/db mice treated with metformin and fed a normal diet containing extruded rice starch without inulin). RESULTS:Physicochemical analysis revealed that resistant starch content was significantly increased by 403.57% in FER compared with extruded rice starch without inulin, which was caused by inulin-starch interactions. Compared with the MOD group, the FER-fed (RERF) group decreased fasting blood glucose by 32.70%, serum creatinine by 50.96%, urea nitrogen by 26.89%, tumor necrosis factor-α by 34.98%, and interleukin-6 by 37.70% (P < 0.05). Histopathology results showed reduced glomerular swelling and colon inflammation in the RERF group compared with the MOD group. Consumption of the FER diet reshaped the profile of gut microbiota, increasing abundances of short-chain fatty acid-producing Anaerostipes and reducing proinflammatory Alistipes. Compared with the MOD group, the RERF group increased acetic acid by 86.88%, propanoic acid by 154.08%, and butanoic acid by 319.56% (P < 0.05). CONCLUSIONS:These findings indicate that FER could be utilized as a food for special dietary use in patients with diabetic kidney, given the dietary fiber-enriched rice's ability to mitigate DKD in an appropriate mouse disease MOD.

Black scraper (Thamnaconus modestus), a commercially valuable filefish species, has suffered substantial depletion in wild stock biomass over recent years, attributed to overexploitation and habitat degradation. Although the rapid expansion of intensive aquaculture has effectively mitigated the global supply-demand gaps, it has simultaneously introduced significant disease risks. Herein, we report a mass mortality incident of black scraper juveniles triggered by viral etiology in land-based mariculture facilities. The epidemic emerged at water temperatures from 22 to 24 degrees C, with affected individuals exhibiting a constellation of pathognomonic symptoms, such as anorexia, imbalance, abnormal swimming, and partial endocranial hyperemia. Histopathological examination revealed diffuse vacuolar degeneration in cerebral and retinal tissues, accompanied by cytoplasmic inclusions comprising aggregates of profuse icosahedral virions. Subsequently, this pathogen was determined as a member of nervous necrosis virus (NNV) belonging to the RGNNV genotype through molecular identification integrated with phylogenetic inference. Crucially, the experimental immersion model utilizing the sterile homogenate from diseased individuals successfully reproduced the full spectrum of clinical manifestations and retinal pathologies observed in natural infections, thereby unequivocally establishing NNV as the primary culprit responsible for this aquacultural crisis. Collectively, this investigation contributes the first scholarly account of NNV infection in black scraper, furnishing vital etiological insights for disease management and mariculture sustainability.

Lipopolysaccharide(LPS),a major component of Gram-negative bacterial cell walls,is commonly used as an inducer of intestinal inflammation in animals,but research on its effects in aquatic animals remains limited. This study focused on blackrock fish,Sebastes schlegelii,an important mariculture species in Shandong Province,using intraperitoneal LPS injection to establish an enteritis model.Evaluation included histopathology,immunoenzymatic activity,tight junction proteins,and inflammatory factor gene expression.The control group received sterile phosphate-buffered saline(PBS),while experimental groups were given low-dose(5 mg/kg LPS),medium-dose(10 mg/kg LPS),and high-dose(15 mg/kg LPS).Each group consisted of three replicates,each with 30 fish(initial body weight 85.3±1.7 g).Samples were collected at 0 h,6 h,12 h,24 h,48 h,72 h,and 96 h post-injection.The results showed that LPS at 5-15 mg/kg effectively induced intestinal structural lesions,inflammatory responses,and oxidative stress,with severity positively correlated to dose.Examination results indicated that the incidence of intestinal damage was 70%in the low-dose group and reached 100%in both the medium-dose and high-dose groups.Histopathological observations revealed intact intestinal structure in controls,whereas LPS groups showed dose-dependent lesions,primarily inflammatory cell infiltration,villi breakage,lysis,and detachment.In the low-dose group,some fish displayed severe villi structural damage,occasional epithelium damage,intact lamina propria,and infiltration of inflammatory cells into the lamina propria and submucosa.In the medium-dose and high-dose groups,fracturing and detachment were observed.The damage to the epithelium and lamina propria was intensified,and infiltration of inflammatory cells was more pronounced.Notably,the high-dose group showed evident villi detachment and a significant reduction in goblet cell lysis.Antioxidant enzyme assay showed that after LPS stress,SOD activity in the high-dose group was significantly reduced versus the control group at 6 h(P<0.05).Additionally,SOD activity in the medium-dose group was significantly lower than the control group at 12 h(P<0.05),and in the low-dose group at 24 h(P<0.05).The overall trend of SOD activity in all experimental groups decreased then increased,remaining significantly lower than that of the control group's at 24 h post-stress(P<0.05).MDA activity differed highly significant between the high-dose group and control group from 12 h post-injection(P<0.001),and the low-dose group differed at 12 h and 24 h(P<0.05),but no significant differences remained at 96 h.ACP activity in all experimental groups was significantly lower than the control group at 6 h(P<0.05).It reached its lowest point at 12 h in the medium-dose and 24 h in the high-dose group,with no significant difference by72 h(P>0.05).AKP activity in the high-dose group was significantly lower than the control group at 6 h(P<0.05),and in all experimental groups at 12 h(P<0.05).AKP activity in the low-dose and medium-dose groups recovered by 48 h,showing no significant difference from the control group.LPS injection altered the expression of inflammation-related genes and tight junction protein genes to varying degrees.The overall level of IL-1β gene expression increased then decreased;specifically,in the high-dose group it was significantly higher than the control group at 6 h(P<0.05).Additionally,the intestinal expression level of IL-8 in all experimental groups was significantly elevated versus the control group at 6 h(P<0.05),remaining significantly higher in the high-dose group at 96 h(P<0.001).The IL-10 gene expression level in the high-dose group was significantly lower than the control group at 6 h(P<0.001),and decreased in the low-dose and medium-dose group at 12 h(P<0.05). After LPS stimulation,NF-κB expression showed an increasing-and-decreasing trend;it was significantly higher in the high-dose group versus the control at 6 h(P<0.05),and in the low-dose and medium-dose groups at 12 h,24 h,and 48 h(P<0.05).In the high-dose group,the expression of occludin and ZO1 genes was significantly down regulated at 6 h(P<0.05),although not at 96 h.In the medium-dose group,their expression was significantly lower at 12 h and 24 h(P<0.001).The relative expression of the ZO1 gene in the low-dose group was significantly lower than that in the control group at 24 h(P<0.05),with no statistically significant differences at other time points.These gene expression changes indicate that LPS can induce an inflammatory response in S.schlegelii. This study demonstrated that LPS induces intestinal tissue damage,compromises antioxidant capacity,and causes abnormal expression of inflammatory-related genes in S.schlegelii.Consequently,LPS functions as a reliable inducer for establishing intestinal inflammation models in S.schlegelii,thereby providing a robust foundation for further in-depth investigation into the pathogenesis of bacterial intestinal inflammation in marine fish and the efficient screening of preventive and therapeutic drugs.

Photobacterium damselae subsp. damselae (PDD), a marine fish pathogen, has an unclear contribution of tonB genes to iron acquisition and pathogenicity. ΔtonB1-PDD and ΔtonB2-PDD mutants as well as their complemented strains were generated via homologous recombination from the virulent strain PDD1605. Growth was evaluated by monitoring OD600 with viable-count calibration, intracellular iron was measured using a colorimetric assay, biofilm was detected by crystal violet staining, transcription was analyzed through qRT-PCR, and pathogenicity was assessed via an 8-day intramuscular challenge in black rockfish (Sebastes schlegelii). Under iron limitation induced by 100 μM 2,2′-dipyridyl, the maximum density decreased from 4.51 × 108 CFU/mL in wild-type (WT-PDD) to 4.00 × 108 and 3.64 × 108 CFU/mL in ΔtonB1-PDD and ΔtonB2-PDD respectively, and was largely restored after complementation. The intracellular iron content declined from 3.75 × 10−4 ± 4.00 × 10−6 nmol/106 cells in WT-PDD to 3.13 × 10−4 ± 1.05 × 10−5 nmol/106 cells in ΔtonB1-PDD and 2.55 × 10−4 ± 2.00 × 10−5 nmol/106 cells in ΔtonB2-PDD. Compared with WT-PDD, biofilm formation was reduced by 22.1% in ΔtonB1-PDD and by 24.8% in ΔtonB2-PDD. Deletion of tonB2 induced mild yet statistically significant transcriptional alterations in multiple iron acquisition and virulence-related genes, while colony morphology, swarming motility, hemolysis, phospholipase activity, biochemical traits, and antimicrobial susceptibility remained unchanged. In the high-dose challenge assay, WT-PDD caused 100% mortality within 2 days, whereas ΔtonB1-PDD and ΔtonB2-PDD caused 17/20 and 18/20 deaths respectively; all infected groups reached 100% mortality by day 3. In the low-dose challenge assay, WT-PDD, ΔtonB1-PDD, and ΔtonB2-PDD caused 12/20, 12/20, and 13/20 deaths by day 2, with cumulative mortalities reaching 80%, 70%, and 80% by day 8, respectively. Kaplan–Meier analysis detected no significant differences among the survival curves at either challenge dose. These findings suggest that tonB1 and tonB2 play roles in iron acquisition, low-iron adaptation, and biofilm formation, with tonB2 deletion exerting greater effects on growth and intracellular iron accumulation under iron-limited conditions.

The inappropriate use of antibiotics in aquaculture has exacerbated antimicrobial resistance in pathogens, thereby reducing the efficiency of aquaculture production. Therefore, it is crucial to develop effective antibiotic alternatives capable of inhibiting pathogenic bacteria. Against this background, the present study investigated the efficacy and underlying mechanism of carvacrol against Vibrio harveyi in the mariculture of the marine fish Sebastes schlegelii, aiming to provide data support for the development of green fishery drugs to replace antibiotics. The results indicated that pre-treatment with carvacrol increased the survival rate of infected S. schlegelii. Meanwhile, post-infection administration of carvacrol alleviated intestinal pathological damage. Carvacrol regulated host immunity by modulating the transcription of the immune-related genes NF-kappa B/RelA and IL-15. Carvacrol did not significantly alter the activities of SOD, MDA, or CAT, suggesting that the oxidative defense pathway was not primarily involved. Analysis of intestinal Vibrio load confirmed that carvacrol could inhibit the growth and colonization of intestinal Vibrio, thereby maintaining microbial homeostasis. Immunohistochemistry and peripheral blood flow cytometry showed that carvacrol enhanced the adaptive immunity of fish by increasing the proportions of CD4-1+ T cells and CD79a/CD79b+ B cells in tissues and peripheral blood. In conclusion, carvacrol enhances the resistance of S. schlegelii against V. harveyi by inhibiting pathogenic bacteria, improving intestinal morphological structure, reducing pathogenic bacterial load to maintain microbial homeostasis, and enhancing the adaptive immunity of the organism. This study provides a theoretical basis and data support for the substitution of antibiotics and the development of green feed additives in aquaculture.

Sous-vide cooking ensures tenderness but often results in limited flavor development. This study investigated microwave pretreatment as a rapid strategy to enhance flavor formation prior to sous-vide processing of chicken breast. The combined treatment significantly increased free amino acids (FAA; 19.51 mg g-1) and umami-related nucleotides, with glutamic acid identified as the dominant contributor. Gas chromatography-mass spectrometry (GC-MS) identified 57 volatile compounds, and the abundance of key odorants increased by 28%-35% (p < 0.05) following microwave-sous-vide treatment. Two-way ANOVA revealed significant synergistic effects (p < 0.01) between microwave duration and sous-vide conditions on both precursor liberation and volatile formation. Overall, microwave-assisted sous-vide processing enhances flavor while retaining the benefits of mild thermal treatment, providing a practical approach for producing high-quality poultry with superior flavor attributes.

Results indicated that pre-treatment with carvacrol significantly increased the survival rate of infected Sebastes schlegelii. Conversely, post-infection administration alleviated intestinal pathological damage. Carvacrol regulated host immunity by modulating the transcription of immune-related genes NF-κB/RelA and IL-15. It had no significant effects on SOD, MDA and CAT, suggesting that the oxidative defense pathway was not involved. Analysis of intestinal Vibrio pathogen load confirmed that carvacrol could inhibit the growth and colonization of intestinal Vibrio, thereby maintaining microbial homeostasis. Immunohistochemistry and peripheral blood flow cytometry showed that carvacrol enhanced the adaptive immunity of fish by increasing the proportions of CD4‑1⁺ T cells and CD79a/CD79b⁺ B cells in tissues. In conclusion, carvacrol enhances the resistance of S. schlegelii against V. harveyi by inhibiting pathogenic bacteria, improving intestinal morphological structure, reducing pathogenic bacterial load to maintain microbial homeostasis, and enhancing the adaptive immunity of the organism. This study provides a theoretical basis and data support for the substitution of antibiotics and the development of green feed additives in aquaculture.

The pond cultured sea cucumber Apostichopus japonicus have been severely impacted by recent outbreaks of the synaptid Protankyra bidentata, which may be attributed to food and nutrient competition between the two species. This study employed stable isotope analysis, high-throughput sequencing of gut contents, and co-culture experiments to investigate their trophic competition. The main findings are as follows: Stable isotope analysis revealed a trophic level of 2.41 +/- 0.10 for P. bidentata and 2.73 +/- 0.05 for A. japonicus, placing both within trophic level II. Both species primarily fed on phytoplankton, accounting for 60.1 % and 79.9 % of their diets, respectively, followed by surface sediments at 15.1 % and 9.8 %. High-throughput sequencing analysis of gut contents revealed similar eukaryotic compositions between P. bidentata and A. japonicus, with primary food groups including vertebrates, fungi, algae, and protozoa. Among these, vertebrates were the most abundant, followed by ascomycetes. In co-culture experiments, A. japonicus in the control group (without P. bidentata) exhibited significantly better growth performance than those in the high-density group (P < 0.05). As the density of P. bidentata increased, the weight gain and specific growth rate of A. japonicus showed a declining trend. These results demonstrate that both P. bidentata and A. japonicus occupy the same trophic level, share similar food sources, and exhibit a distinct competitive relationship. The synaptid P. bidentata is thus identified as an emerging pest that suppresses the growth of pond-cultured A. japonicus through food competition.

Starch-based films have significant potential in food packaging and biomedicine. However, the poor mechanical properties and hydrophobicity restrict their applications. In the present study, the physicochemical properties of starch/rosin composite films were examined to reveal the interaction mechanism between the lipophilic rosin and hydrophilic starch phases. The water contact angle of composite films progressively increased, while the moisture content, swelling ratio, and soluble solid loss ratio decreased as the content of rosin rose. At 20% rosin content, the composite film exhibited optimally balanced properties, characterized by the lowest water vapor permeability (4.21 ± 0.24 × 10-12 g·Pa-1·s-1·cm-1) and the highest tensile strength (8.39 ± 0.49 MPa). Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis indicated that the composite film exhibited a moderate phase-separated structure. The incorporated rosin molecules facilitated the uniform rearrangement of starch molecules into a compact network by the extrusion effect. The starch network, in turn, restricted the aggregation of rosin and promoted its homogeneous distribution. The composite films loaded with trans-cinnamaldehyde had obvious inhibitory activity against S. aureus and E. coli. The release kinetics of trans-cinnamaldehyde in the composite films followed the Ritger-Peppas model, it represents a combination kinetics of diffusion and carrier erosion. The work would provide a new strategy for the development of biobased hydrophobic active packaging.

Most previous research focuses on single-state palm oil (PO) modification of starch films, while the interaction between different physical states PO and starch matrix has not been deeply discussed. This study aimed to investigate the effects of PO nanoparticles in three physical states (liquid, semi-solid, solid) on starch-based films, where the physical state of PO nanoparticles was regulated by manipulating the melting point of PO. PO nanoparticles with five different melting points (8, 24, 33, 42, and 53 °C) were prepared at 30 °C using emulsification with sodium caseinate as the emulsifier and were integrated within a starch matrix to fabricate films. The findings revealed that the starch film with 33 °C PO nanoparticles had the smoothest and most homogeneous surface, the best dispersion state of the oils, the optimal compatibility, and the highest film crystallinity. These films exhibited enhanced tensile strength (TS), stiffness, and barrier properties. Furthermore, starch films containing solid nanoparticles exhibited superior thermal stability. This study innovatively prepared nano-scale palm oil-starch composite films and revealed the pivotal role of the viscoelastic attributes of semi-solid PO nanoparticles in enhancing the qualities of starch-based films.

The impact of phase separation behavior on the performance of hydrogels has always been the research focus. This study explored the relationship of "pH-microstructure-hydrogel properties" of phase-separated hydrogels composed of type-A gelatin (GE, 5 wt%) and hydroxypropyl starch (HPS, 3 wt%). The results revealed that changes in the microstructure of the hydrogel at different pHs significantly impacted the gel properties. At pH 4.00 and 11.00, phase separation occurred in the GE/HPS gel with a microstructure of HPS-in-GE. In particular, at pH 5.00, 6.00, 7.00, and 9.00, severe phase separation resulted in the separation of substantial aggregates of HPS and GE, resulting in a continuous phase structure. At pH 2.00 and 3.00, phase separation was suppressed, resulting in a homogeneous microstructure. Compared to the phase-separated gels at pH 4.00-11.00, the homogeneous systems at pH 2.00 and 3.00 displayed a synergistic effect with higher gel strength. Analysis of intermolecular forces in the GE/HPS gel indicated that hydrogen bonding was the primary interaction force. Furthermore, the addition of GE/HPS into hawthorn jelly at about pH 3.00 effectively preserved the structural appearance and exhibited higher levels of hardness, thus improving the sensory properties of hawthorn jelly. In summary, phase separation decreased the storage modulus of GE/HPS gel, but the compatibility of GE/HPS macromolecules exhibited synergistic effects at 2.00 and 3.00 and improved the hydrogel mechanical properties. This work provides some new insights for GE/HPS-based gel foods.

Conventional farming does not meet the future feeding conditions of bighead carp (Hypophthalmichthys nobilis) in high-density culture mode. The aim of this study was to investigate the effects of supplemental feeding of artificial protein feeds of different contents on the gut microbiome and metabolome of bighead carp in the traditional culture model. Bighead carp were fed with 30 % (LG, low protein group), 40 % (HG, high protein group) artificial protein feed and plankton only (PG, plankton group) for eight weeks, respectively. We used 16S ribosomal ribonucleic acid sequencing and liquid chromatography-mass spectrometry (LC-MS) techniques to study three groups of bighead carp. The results showed that the weight gain rate and specific growth rate were significantly increased in HG and LG compared to PG. There were significant differences in the abundance of gut microbiota among the three groups of bighead carp, such as increased Bacteroidota and Acetobacteroides (P < 0.05) in HG. In addition, metabolomic analyses of the three groups identified a total of 975 compounds. KEGG enrichment analyses showed that differential metabolites between the different groups were mainly enriched in the gastric acid secretion, vitamin B6 metabolism, arginine and proline metabolism, and tryptophan metabolism pathways. Overall, the addition of an artificial feed with a protein level of 40 % to traditional culture method promotes the amino acid metabolism in the gut microbiota of bighead carp and improves growth performance. These analytical data provide new insights for replacing the traditional culture mode and provide a theoretical basis for optimizing the composition of bighead carp feeds.

Propionate-acylated resistant starch has garnered attention for its unique ability to infuse specific SCFAs in the distal colon. Here, MPS with an elevated level of resistant starch was first prepared. Then, the effects of MPS on hepatic steatosis and the gut mycobiome were investigated in mice. Specifically, microcrystalline pea starch, serving as the starting material, underwent esterification with propionic anhydride to produce MPS. With the supplementation of propionic anhydride, the novel characteristic peaks were observed and the relative crystallinity of MPS was increased, according to FT-IR and XRD analysis, respectively. Moreover, the resistant starch content increased from 64.38 % in MPS1 (DS 0.0505) to 93.26 % in MPS5 (DS 0.2511). Additionally, MPS5 supplementation decreased hepatic steatosis and intestinal dysfunction in HFD-fed mice and increased the propionic acid in the faeces of HFD-fed mice, indicating that the introduced propionyl groups were successfully delivered to the colon and improved hepatic lipid metabolism. Fungal-specific internal transcribed spacer amplicon sequencing revealed that MPS5 modified the gut mycobiome composition in HFD-fed mice, with increases in Penicillium and Colletotrichum, which are linked to the anti-hepatic steatosis benefit. Overall, the present research provides a reference for the design of resistant starch that can produce high levels of propionate, modulate the gut mycobiome, and produce anti-hepatic steatosis benefits.

As the adsorption receptor of bacteriophage tail protein, bacterial lipopolysaccharide (LPS) is a main culprit responsible for nonalcoholic fatty liver disease (NAFLD) caused by high-fat diets. However, few studies have focused on how the interaction between intestinal bacteriophages and bacterial LPS affects the development and progression of NAFLD. Herein, we determined that excessive fat intake significantly increases the levels of endogenous LPS, while the administration of beneficial metabolites of the intestinal microbiota (specifically butyrate) alleviated hepatic injury in rats. The beneficial mechanism of butyrate was attributed to the reprogramming of the structure of the intestinal DNA virome (primarily, phageome). Butyrate possesses the potential to augment bacteriophagic microbial diversity, thereby potentially facilitating interactions between intestinal bacteriophages and bacterial LPS (in the case of homologous phage), further improving mitochondrial dysfunction and reactive oxygen species production, which, in turn, lowered HepG2 cell damage. Likewise, fecal phage transplantation further confirmed that intestinal phages from rats that received butyrate could effectively interact with bacterial LPS to reduce liver damage in rats. Taken together, modifying the intestinal phageome is a promising treatment option for high-fat diet-related NAFLD.

Gray mold, caused by Botrytis cinerea, presents a serious problem to the table grape industry. Sulfur dioxide (SO2) can protect berries from pathogenic fungal infections by exerting biological functions, but the underlying mechanisms remain largely unknown. To investigate the mechanism by which SO2 enhances postharvest grape disease resistance through reactive oxygen species (ROS) pathway, grapes were fumigated with SO2 (500 mu L L- 1) and then inoculated with B. cinerea. The results showed that SO2 effectively inhibited the expansion of B. cinerea on postharvest grapes. SO2 promoted the transient production of superoxide anions and hydrogen peroxide (H2O2) during the initial stage (in the first 9 h) by rapidly increasing the enzyme activities and gene expression of respiratory burst oxidase homologs and superoxide dismutase. From 1-7 d, the ROS and malondialdehyde levels were significantly reduced by SO2. Further analysis showed that SO2 can boost the antioxidant capacity of berries (total antioxidant capacity, and ABTS and DPPH scavenging capacities) by promoting ROS scavenging enzyme activities and the ascorbate-glutathione (AsA-GSH) cycle. In addition, the expression of ROS scavenging-related, AsA-GSH cycle-related genes, and VvPRs was effectively upregulated by SO2. Together with correlation analysis results, we propose that the initial H2O2 signal contributes to improved antioxidant capacity and upregulation of VvPRs, which plays a crucial role in strengthening the long-term resistance of postharvest grapes to B. cinerea. In conclusion, SO2 can enhance postharvest grape resistance to gray mold by leveraging the H2O2 signaling pathway, highlighting its pivotal role in activating the defense mechanisms of plants.

Guanidine disinfectants are cationic polymers recognized for their effective sterilization properties and their ability to prevent bacterial resistance. As a result, they are widely utilized in medical, healthcare, household, and animal husbandry settings. However, the bactericidal effects and mechanisms of guanidine in marine aquaculture systems remain unclear due to the polymeric nature of guanidine ions and the complexity of marine environments. The inhibitory effects and bactericidal mechanisms of polyhexamethylene biguanide (PHMB) on key pathogens and probiotics are examined in this study. It was shown that PHMB had inhibitory effects on Vibrio parahaemolyticus (VP), Photobacterium damselae subsp. damselae (PDD), Bacillus subtilis (BS), Escherichia coli (EPEC), and Staphylococcus aureus (SAU), with minimum inhibitory concentrations (MICs) ranging from 3.91 to 125.0 µg/mL, and minimum bactericidal concentrations (MBCs) from 15.63 to 250.0 µg/mL. A stronger bactericidal effect of PHMB on marine bacteria compared to EPEC and SAU was exhibited. It was shown in ion interference experiments that the addition of calcium ions reduced the bactericidal effectiveness of PHMB against VP and PDD by 87.73% and 53.35%, respectively. At a PHMB concentration of 62.50 µg/mL, minor changes in cell surface potential energy (CSPE) were exhibited by Gram-positive bacteria (SAU and BS), while more significant alterations were shown by Gram-negative pathogens. It was revealed by propidium iodide staining and scanning electron microscopy (SEM) analysis that the bacterial cell membrane was directly disrupted by PHMB. DNA and RNA release analysis further revealed that following PHMB treatment, changes in membrane permeability were exhibited by Gram-negative pathogens, with a significant increase in extracellular DNA content as PHMB concentration increased. No such effect was observed in Gram-positive bacteria. Additional evidence was provided by the findings that PHMB effectively inhibits bacterial pathogens in mariculture systems, with a significantly stronger inhibitory effect on Gram-negative pathogens than on Gram-positive bacteria. These results indicated that PHMB could serve as a new antimicrobial agent in mariculture.

Chlorpyrifos, a widely used organophosphorus insecticide, poses a potential hazard to marine ecosystems due to its toxicity to aquatic organisms. However, the ecological risks of chlorpyrifos to marine organisms remain unclear. This study employed species sensitivity distributions (SSDs) to assess the ecotoxicological effects of chlorpyrifos on marine ecosystems, with a focus study in Laizhou Bay, China. Our results revealed the hazardous concentration for 5 % of species (HC5) for indigenous, non-indigenous, and all marine species were 1.341, 0.0231, and 0.0872 mu g/L, respectively. The predicted no-effect concentrations (PNECs) demonstrate significant temporal variation, with short-term values of 0.6705, 0.0116, and 0.0436 mu g/L, and long-term values of 0.0838, 0.0015, and 0.0055 mu g/L for indigenous, non-indigenous, and all species, respectively. Non-indigenous species exhibited higher sensitivity to chlorpyrifos than indigenous species. Risk assessment based on risk quotients (RQs) revealed distinct temporal patterns: short-term RQs ranged from 0.001 to 0.094 across different species groups, while long-term RQs showed higher values ranging from 0.004 to 0.727. These findings indicated minimal short-term ecological risk, but moderate long-term risk, particularly for non-indigenous species. Our study provides compelling evidence that chlorpyrifos poses a potential threat to the ecosystem of Laizhou Bay. These findings offer crucial scientific data for establishing water quality standards for chlorpyrifos in China and developing effective management strategies for pesticide pollution in marine environments.

This study aimed to investigate the influence of ultrasound treatment on the structural and gelation properties of soy protein isolate (SPI)-sesbania gum (SG) composite gels induced by varying concentrations of CaSO4. The results showed that ultrasound treatment at amplitudes ranging from 20 % to 60 % for 10 min improved protein solubility, rheological properties and gel strength. The addition of CaSO4 (15 to 35 mM) further increased gel hardness but caused a decline in the water-holding capacity (WHC). Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) demonstrated that ultrasound treatment promoted the formation of a more homogenous and compact network in SPI-SG gels, improving WHC. Although higher concentrations of CaSO4 resulted in an uneven network with larger pores and reduced WHC, ultrasound treatment mitigated the loss. Moreover, analysis of intermolecular forces revealed that ultrasound treatment enhanced hydrophobic interactions and disulfide bonds within the mixed gels induced by CaSO4, leading to a stronger gel network. These findings provided a novel strategy for improving SPI-based gel properties and offer a theoretical basis for the application of SPI-SG complex in food processing.