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The sea cucumber is an essential nutrient source and a significant economic marine resource associated with successful aquaculture. However, sea cucumbers are highly susceptible to autolysis induced by endogenous protease after postmortem, and the phenomenon of body wall "melting" occurs, which seriously affects the food quality of products and the degree of acceptance by consumers. To satisfy the growing demand for fresh or processed sea cucumbers, we must clarify the autolysis mechanism of sea cucumbers and the methods to achieve autolysis regulation. In this paper, the factors leading to the quality deterioration and texture softening of sea cucumbers are reviewed, with emphasis on enzymatic characteristics, the autolysis mechanism, the effects of autolysis on the physicochemical properties of the body wall of the sea cucumber, and the development of potential natural protease inhibitors. We aim to provide some reference in future preservation and processing processes for sea cucumbers, promote new processing and preservation technologies, and advance the sea cucumber industry's development.
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Modification is widely used to enhance the adsorption performance of pristine hydrochar (HBC) and pyrochar (BC). However, comparisons between modified HBC and BC toward pollutant removal have rarely been reported. In this study, pristine HBC and BC derived from rice straw were first produced, and then citric acid (CA) was used as a modifier to synthesize CA-modified HBC (CAHBC) and CA-modified BC (CABC). Furthermore, the adsorption performance of biochars toward methylene blue (MB) was investigated. The results showed that BC exhibits relatively rough surfaces and contains more minerals (ash), whereas HBC has plentiful O-containing functional groups and fewer minerals. CA modification partially removed minerals from the surface of BC, which weakened the ion exchange, surface complexation, and n-π interaction, resulting in a lower adsorption ability toward MB. By contrast, CA produced more O-containing functional groups on the surface of HBC, which strengthened the hydrogen bonding and electrostatic interaction, thus increasing the adsorption capacity toward MB. The two-compartment model showed a good fit to the adsorption process of MB on CAHBC, and the isotherm data for MB adsorption by HBC and CAHBC are suitable for the Freundlich model. The highest adsorption amount of MB using CAHBC was 80.13 mg·g-1, which was 27.66% higher than that for CABC. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis indicated that the carboxyl groups in the surface functional groups of CAHBC played a crucial role in the MB adsorption process. In addition, CAHBC showed a good performance for a wide range of pH values (4.0-10.0) and under the interference of coexisting ions, and also presented a recycling ability. Furthermore, the adsorption of MB on CAHBC biochar was a spontaneous, exothermic, degree-of-randomness-increasing process. Consequently, CA modification of HBC is a promising strategy and could be used for MB removal from aquatic environments.
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Carvão Vegetal , Ácido Cítrico , Azul de Metileno , Minerais , Poluentes Químicos da Água , Azul de Metileno/química , Adsorção , Ácido Cítrico/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Minerais/química , Oxigênio/químicaRESUMO
BACKGROUND: The quality of surimi-based products can be improved by combining the flesh of different aquatic organisms. The present study investigated the effects of incorporating diverse ratios of unwashed silver carp (H) and scallop (A) and using various thermal treatments on the moisture, texture, microstructure, and conformation of the blended gels and myofibrillar protein of surimi. RESULTS: A mixture ratio of A:H = 1:3 yielded the highest gel strength, which was 60.4% higher than that of scallop gel. The cooking losses of high-pressure heating and water-bath microwaving were significantly higher than those of other methods (P < 0.05). Moreover, the two-step water bath and water-bath microwaving samples exhibited a more regular spatial network structure compared to other samples. The mixed samples exhibited a microstructure with a uniform and ordered spatial network, allowing more free water to be trapped by the internal structure, resulting in more favorable gel properties. The thermal treatments comprehensively modified the tertiary and quaternary structures of proteins in unwashed mixed gel promoted protein unfurling, provided more hydrophobic interactions, enhanced protein aggregation and improved the gel performance. CONCLUSION: The findings of the present study improve our understanding of the interactions between proteins from different sources. We propose a new method for modifying surimi's gel properties, facilitating the development of mixed surimi products, as well as enhancing the efficient utilization of aquatic resources. © 2024 Society of Chemical Industry.
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Biochar preparation and application is an anticipated pathway for the resource utilization of biogas residue. In this study, biochars were prepared by the pyrolysis of biogas residue from food waste anaerobic digestion (named as BRBCs) under various pyrolysis temperatures (300, 500, 700, and 900 °C), and the effect of pyrolysis temperatures on the physicochemical characteristics of BRBCs was examined. The adsorption performance toward ciprofloxacin (CIP), a typical antibiotic in waterbodies, was also investigated. The results showed that pyrolysis temperature significantly changed the physicochemical properties of BRBCs. In addition, the minerals in the biogas residue, especially SiO2, were rearranged to form a mesoporous structure in biochar through a self-template strategy (without activator). BRBC prepared at 900 °C exhibited a high specific surface area and pore volume, well-developed mesopore structure, and more carbon structure defects, and exhibited the largest CIP adsorption capacity with 70.29 mg g-1, which was ascribed to the combined interaction of pore diffusion, π-π interactions, hydrogen bonding, complexation, and electrostatic forces. Furthermore, the adsorption of CIP by BRBC900 was well described by two-compartment kinetic and Langmuir isotherm models. BRBC900 showed good adsorption performance toward CIP at pH 7-9. The adsorption of CIP by BRBC is a spontaneous, exothermic, entropy-increasing process. Moreover, BRBC also presented a good recycling potential. Therefore, the preparation of mesoporous biochar based on a self-template strategy not only provides an option for the resource utilization of biogas residue but also offers a new option for the treatment of antibiotic wastewater.
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Biocombustíveis , Carvão Vegetal , Ciprofloxacina , Pirólise , Ciprofloxacina/química , Carvão Vegetal/química , Biocombustíveis/análise , Adsorção , Poluentes Químicos da Água/química , Temperatura , Porosidade , CinéticaRESUMO
Aquatic products are gaining popularity due to their delicacy and high nutrient value. However, they are perishable, with a short shelf-life. Frozen storage is associated with adverse effects, leading to protein oxidation and degradation, thereby altering the protein's structural integrity and subsequently influencing the palatability of protein-based food products. To address these challenges, novel antifreeze peptides have gained significant attention. Antifreeze peptides are a class of small molecular weight proteins or protein hydrolysates that offer protection to organisms in frozen or sub-frozen environments. They offer distinct advantages over conventional commercial antifreeze agents and natural antifreeze proteins. This review provides an overview of the current state of research on antifreeze agents, elucidates their characteristics and mechanisms, and examines their applications in aquatic products. Furthermore, the article offers insights into the prospective development and application prospects of antifreeze peptides.
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Impact of high-pressure processing (HP-P) on hemolymph and lipid globular structures of the edible portion (EP) of blood clams (BC) was investigated. HP-P above 400 MPa decreased heme iron content, while upsurged non-heme iron content. Increasing pressure induced gaps and abnormal hemocyte cell arrangements. However, HP-P at 300 MPa improved and maintained total hemocyte counts, the heme iron content, and a*-value in BC-EP. For lipid globular structures, the mean diameter drastically decreased when an HP-P pressure of 600 MPa was employed. HP-P at higher pressure induced lipid oxidation, along with decreases in monounsaturated and polyunsaturated fatty acids as well as increases in thiobarbituric acid reactive substances and peroxide value. FTIR spectra displayed a reduction in phosphate groups and cis double bonds in lipids from HP-P treated BC, compared to controls. Therefore, HP-P at 300 MPa is recommended for preparing ready-to-cook BC with less tissue damage and lipid oxidation.
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Bivalves , Hemolinfa , Animais , Peroxidação de Lipídeos , Ácidos Graxos Insaturados , Heme/química , FerroRESUMO
How to increase the response of immune checkpoint inhibitors (ICIs) is a challenge. In clinical, we found that Zoledronic acid (ZA) may increase the anti-tumor effect of immunotherapy for hepatocellular carcinoma (HCC). To explore the underlying mechanism, we established a mouse model of HCC by subcutaneously injecting Hepa1-6 cell line. The result showed that the tumor volume in the ZA plus anti-PD-1 monocloning antibody (anti-PD-1 mAb) treatment groups was significantly smaller than that of control group, and the onset time of tumor inhibition was even shorter than that of the anti-PD-1 mAb group. Using flow cytometry (FC) to detect the proportion of major immune cell subsets in tumor tissues of each group of mice, we found that the synergistic anti-tumor effect of ZA and anti-PD-1 mAb may be related to ZA-induced polarization of macrophages toward the M1 phenotype. Next, we performed bulk RNA sequencing on tumor samples from different groups to obtain differentially expressed genes (DEGs), which were then input DEGs into pathway enrichment analysis. Data indicated that ZA participated in the M1-type polarization via ferroptosis-related pathways. Our results revealed how ZA involves in the anti-tumor effect of PD-1 monoclonal antibody and provided a potential therapeutic candidate for patients with HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/metabolismo , Ácido Zoledrônico/farmacologia , Ácido Zoledrônico/uso terapêutico , Receptor de Morte Celular Programada 1 , Neoplasias Hepáticas/metabolismo , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
In conventional fish soup processing, valuable aquatic resources like fish skins, bones, and scales are often squandered. This study was aimed at investigating if comminution combined with pressure-conduction treatment has the potential to enhance the reutilization of cooking residues. The different blending ratios of original soup (OS), made from the initial cooking of fish, and residue soup (RS), produced from processed leftover fish parts, were alternatively investigated to satisfy the new product development. Comminution combined with pressure-conduction treatment significantly increased the nutrient contents of calcium, soluble proteins and total solids in crucian carp soup (p < 0.05). With the increase in RS ratio, the decomposition of inosine monophosphate (IMP) and free amino acids was accelerated, but the accumulation of aromatic compounds was promoted simultaneously. In addition, the Maillard reaction may lead to a reduction in aldehydes, causing a diminution in the characteristic flavor of fish soup, while the formation of 1-octen-3-ol can enhance the earthiness of the fish soup. The electronic tongue test results and the sensory results showed that the blend ratio of OS and RS at 7:3 had a more significant umami and fish aroma (p < 0.05). Under this condition, the mixed soup has better nutritional values and flavor characteristics.
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This study investigated the effects of different cooking methods on non-volatile flavor (free amino acids, 5'-nucleotides, and organic acids, etc.) of Coregonus peled meat. The volatile flavor characteristics were also analyzed by electric nose and gas chromatography-ion migration spectrometry (GC-IMS). The results indicated that the content of flavor substances in C. peled meat varied significantly. The electronic tongue results indicated that the richness and umami aftertaste of roasting were significantly greater. The content of sweet free amino acids, 5'-nucleotides, and organic acids was also higher in roasting group. Electronic nose principal component analysis can distinguish C. peled meat cooked (the first two components accounted for 98.50% and 0.97%, respectively). A total of 36 volatile flavor compounds were identified among different groups, including 16 aldehydes, 7 olefine aldehydes, 6 alcohols, 4 ketones, and 3 furans. In general, roasting was recommended and gave more flavor substances in C. peled meat.
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Biochar preparation was a feasible strategy for realizing the reduction, harmlessness, and resource utilization of biogas residue (BR) simultaneously. How to enhance the adsorption performance of biogas residue biochar through simple, friendly, and effective way still needs to be investigated. In this study, water-washing pretreatment of BR was adopted before biochar preparation (BRBC-W), and pristine biochar (BRBC) was also produced to serve as control. The adsorption behavior and possible adsorption mechanisms of tetracycline (TC) onto biochars were comprehensively studied. The results showed that water-washing pretreatment could increase the surface area and mesoporous volume of biochar from 358.63 to 391.98 cm3âg-1, and 0.459 to 0.488 cm3âg-1, respectively. More graphitic structure was observed in BRBC-W. In addition, the surface morphology, element content, minerals composition, and surface functional groups also changed in biochar after water-washing pretreatment. The pseudo-second-order and Redlich-Peterson models better descried the adsorption behavior of TC on BCRBC-W. The maximum adsorption capacity of BRBC and BRBC-W for TC based on Langmuir isotherm was 224.93 and 306.94 mg·g-1, respectively. The adsorption affinity of BRBC-W toward TC was greater than that of BRBC. BRBC and BRBC-W can effectively remove TC in water within a wide pH range and under the interference of co-existing ions. The adsorption mechanism of TC onto BRBC and BRBC-W included ore filling, π-π interaction, and hydrogen bonding. The enhancement of TC on BRBC-W by water-washing pretreatment was attributable to the strengthening of pore diffusion and π-π interaction. Therefore, water-washing pretreatment effectively enhanced the adsorption performance of BRB, and BRBC-W was an effective eco-friendly adsorbent for the removal of TC from aquatic environment.
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Biocombustíveis , Poluentes Químicos da Água , Adsorção , Água , Tetraciclina/química , Antibacterianos , Carvão Vegetal/química , CinéticaRESUMO
Introduction: Previous research suggests that high-power (HP) individuals are stereotyped as positive competence but negative warmth. Object: By subdividing HP individuals into junior and senior HP individuals, the current research conducted five studies to examine the warmth perception differences toward senior and junior HP individuals in Confucian culture and the downstream effects on spontaneous trait inference (STI). Method and results: By using different paradigms, Study 1 and 2 found that participants tended to perceive junior HP individuals as negative on the warmth dimension and perceive senior HP individuals as positive on the warmth dimension. The following Study 3 and 4 further found that the warmth perception difference toward senior and junior HP individuals had an influence on STI. Specifically, participants were inclined to make STI from behaviors implying negative warmth traits when behavioral actors were junior HP individuals while they were inclined to make STI from behaviors implying positive warmth traits when behavioral actors were senior HP individuals. Additionally, Study 4 found that perceived social responsibility about HP individuals accounted for the power stereotype effects in STI, the more social responsibility participants perceived about senior HP individuals, the stronger power stereotype effects they showed in STI. The final Study 5 revealed that the different power stereotype effects in STI induced by senior and junior HP actors were observed only in Confucian culture, but not in non-Confucian culture. Conclusion: The present research firstly demonstrated that the warmth perceptions about senior and junior produced different influences on STI in Confucian culture, and also enriched the understanding about the culture-specificity of the stereotype content model.
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Peracetic acid (PAA) serves as a potent and low-toxic oxidant for contaminant removal. Radical-mediated catalytic PAA oxidation processes are typically non-selective, rendering weakened oxidation efficacy under complex water matrices. Herein, we explored the usage of reduced graphene oxide (rGO) for PAA activation via a non-radical pathway. Outperforming the most catalytic PAA oxidation systems, the rGO-PAA system exhibits near-complete removal of typical micropollutants (MPs) within a short time (<2 min). Non-radical direct electron transfer (DET) from MPs to PAA plays a decisive role in the MP degradation, where accelerated DET is achieved by a higher potential of the rGO-PAA reactive surface complexes. Benefitting from DET, the rGO-PAA system shows robust removal of multiple MPs under complex water matrices and with low toxicity. Notably, in the DET regime, the electrostatic attraction of rGO to both PAA and target MP is a critical prerequisite for achieving efficient oxidation, depending on the conditions of solution pH and MP pKa. A heatmap model building on such an electrostatic interaction is further established as guidance for regulating the performance of the DET-mediated PAA oxidation systems. Overall, our work unveils the imperative role of DET for rGO-activated PAA oxidation, expanding the knowledge of PAA-based water treatment strategies.
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Ácido Peracético , Poluentes Químicos da Água , Elétrons , Grafite , Peróxido de Hidrogênio , OxirreduçãoRESUMO
Endowing ceramic membrane (CM) catalytic reactivity can enhance membrane fouling control in the aid of in situ oxidation process. Peracetic acid (PAA) oxidant holds great prospect to integrate with CM for membrane fouling control, owing to the prominent advantages of high oxidation efficacy and easy activation. Herein, this study, for the first time, presented a PAA/CM catalytic filtration system achieving highly-efficient protein fouling alleviation. A FeOCl functionalized CM (FeOCl-CM) was synthesized, possessing high hydrophilicity, low surface roughness, and highly-efficient activation towards PAA oxidation. Using bovine serum albumin (BSA) as the model protein foulant, the PAA/FeOCl-CM catalytic filtration notably alleviated fouling occurring in both membrane pores and surface, and halved the flux reduction degree as compared with the conventional CM filtration. The PAA/FeOCl-CM catalytic oxidation allows quick and complete disintegration of BSA particles, via the breakage of the amide I and II bands and the ring opening of the aromatic amino acids (e.g., Tryptophan, Tyrosine). In-depth investigation revealed that the in situ generated â¢OH and 1O2 were the key reactive species towards BSA degradation during catalytic filtration, while the organic radical oxidation and the direct electron transfer pathway from BSA to PAA via FeOCl-CM played minor roles. Overall, our findings highlight a new PAA/CM catalytic filtration strategy for achieving highly-efficient membrane fouling control and provide an understanding of the integrated PAA catalytic oxidation - membrane filtration behaviors.
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Ácido Peracético , Purificação da Água , Cerâmica , Filtração , Membranas Artificiais , Soroalbumina Bovina , Purificação da Água/métodosRESUMO
The advantages of super-chilling storage at -2 °C for maintaining the quality of Coregonus peled muscle were investigated using the rigor-mortis index (RM), ATP-related compounds, K-value, muscle hardness, impedance measurement, and total viable count. The results indicated that the softening of fish muscle and increase in K-value were substantially suppressed following storage at -2 °C compared to that at 0 °C. In particular, the hardness of fish muscle stored for 6 days at -2 °C was much higher than that of the samples stored for 2 days at 0 °C. The K-value increased to 81% after 6 days at 0 °C, while increased to 57% at -2 °C. The impedance changed in a biphasic manner throughout the storage period. The initial increase accompanied by the progression of RM was followed by a gradual decrease. However, this decrease was much slower at -2 °C than 0 °C. Furthermore, proteomics analysis demonstrated that the mechanism of fish freshness changes between the two storage temperatures. Differentially abundant proteins between the samples stored at two temperatures were mainly involved in the cellular component and molecular function (GO pathway) as well as collagen digestion (KEGG pathway), which might be related to muscle textural properties. Therefore, super-chilling storage is a possible method for maintaining the freshness of Coregonus peled.
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Proteômica , Indicadores de Qualidade em Assistência à Saúde , Animais , Peixes , Rigor MortisRESUMO
This study aimed to evaluate the freshness of ice stored rainbow trout by bioelectrical impedance measurements. Rigor mortis, ATP-related components, K-value, and hardness of rainbow trout muscle during storage were monitored along with impedance. The results showed that the progress of rigor mortis was accompanied by an increase in impedance. Impedance kept decreasing even in rigor state, and during the gradual resolution of rigor mortis with impedance change upon storage of fish was biphasic (r = -0.944, p < .01). Thus, when impedance decreased close to the lowest value, K-value was only about 61.57 ± 0.52%, but still exhibited a high pertinence (r = -0.959, p < .01). A gradual decrease of the hardness of fish muscle upon storage of fish showed a close correlation (r = 0.981, p < .01) with impedance decrease. These results suggested that the impedance measurement has a great potential for predicting the freshness of the rainbow trout during ice storage.
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In this study, effects of different steaming conditions (temperature-time scales) on quality characteristics of cooked whitefish (Coregonus peled) were characterized to guide product development. Investigation of three cooking conditions, including 60°C (3-20 min) 80°C (1-12 min) and 100°C (1-6 min) indicated that properties including textural properties, cooking loss, color change, water holding capacity (WHC), and protein content were all significantly correlated to the cooking condition. It was observed that the color changes of fish meat, especially the brightness L* were strongly correlated to the relative extraction rate (RER) of myofibrillar proteins (MFPs), which could be considered as a marker for the doneness of the cooked whitefish. Our results indicated that during the steaming process, the water holding capacity of the fish continued to decline, and the cooking loss continued to increase. However, a sudden jump in cooking loss occurred when the fish sample became overcooked. To minimize cooking loss, a good control of the doneness hence is needed to avoid overcooking. Moreover, results of this study demonstrated that low-temperature steaming could better maintain the springiness and cohesiveness of the fish as the myofibrillar proteins experienced less sudden swelling and shrinkage. Hence, low temperature steaming should be the preferred method for whitefish processing to minimize the negative impact on fish sensory qualities.