Evaluating the effects of graphene nanoparticles combined radio-frequency thawing on the physicochemical quality and protein conformation in hairtail (Trichiurus lepturus) dorsal muscle.

BACKGROUND: The thawing process is an essential step for a frozen marine fish. The present study aimed to investigate the effects of graphene magnetic nanoparticles combined radio-frequency thawing methods on frozen hairtail (Trichiurus lepturus) dorsal muscle. Seven thawing methods were used: air thawing, 4 °C cold storage thawing, water thawing, radio-frequency thawing (RT), radio frequency thawing combined with graphene nanoparticles (G-RT), radio frequency thawing combined with graphene oxide nanoparticles (GO-RT) and radio-frequency thawing combined with graphene magnetic nanoparticles (GM-RT). The thawing loss and centrifugal loss, electric conductivity, total volatile basic nitrogen, thiobarbituric acid reactive substances and color of thawed hairtail dorsal muscle were determined. The carbonyl content, total sulfhydryl groups, Ca2+ -ATPase activity, raman spectroscopy measurements and Fourier-transform infrared spectrometry measurements were determined using myofibrillar extracted from the dorsal muscle of hairtail. The water distribution was determined using low-field NMR techniques. RESULTS: The results demonstrated that the RT, G-RT, GO-RT and GM-RT could significantly shorten the thawing time. Moreover, GO-RT and GM-RT efficiently preserved the color of fish dorsal muscle and reduced the impact of thawing on fish quality by reducing lipid and protein oxidation. Meanwhile, the myofibrillar protein structure thawed by GO-RT and GM-RT were more stable and had a more stable secondary structure, which maintained strong systemic stability at the same time as slowing down protein oxidation. CONCLUSION: The results showed that GO-RT and GM-RT can significantly improve the thawing efficiency at the same time as effectively maintaining and improving the color and texture of thawed fish, slowing down the oxidation of proteins and lipids, and maintaining a good quality of thawed fish meat. © 2023 Society of Chemical Industry.

Influences of two transport strategies on AMPK-mediated metabolism and flesh quality of shrimp (Litopenaeus vannamei).

BACKGROUND: Water-free transportation (WFT), as a novel strategy for express delivery of live shrimp (Litopenaeus vannamei), was developed recently. However, air exposure during this transportation arouses a series of abiotic stress to the shrimp. In the present study, the influences of WFT stress on glycolysis and lipolysis metabolism and meat quality (umami flavor and drip loss) were investigated in comparison with conventional water transportation (WT). RESULTS: The results showed that type II muscle fibers with the feature of anaerobic metabolism were dominated in shrimp flesh. In addition, the increments of intracellular Ca2+ was detected in WFT and WT, which then activated the AMP-activated protein kinase pathway and promoted the consumption of glycogen, as well as the accumulation of lactate and lipolysis, under the enzymolysis of hexokinase, pyruvate kinase, lactate dehydrogenase and adipose triglyceride lipase. Glycogen glycolyzed to latate. Meanwhile, ATP degraded along with glycolysis resulting in the generation of ATP-related adenosine phosphates such as inosine monophosphate with umami flavor and phosphoric acid. More remarkable (P < 0.05) physiological changes (except lactate dehydrogenase and lactate) were observed in WFT compared to WT. Additionally, the fatty acid profile also slightly changed. CONCLUSION: The transport stress induced significant energy metabolism changes of shrimp flesh and therefore effected the flesh quality. The intensifications of freshness (K-value) of shrimp flesh were detected as a result of ATP degradation, which were more pronounced after WFT. However, the drip loss of shrimp flesh was more significantly increased (P < 0.05) after WFT compared to WT. © 2023 Society of Chemical Industry.

The impact of ice slurry as a medium on oxidation status and flesh quality of shrimp (Litopenaeus vannamei) during refrigeration storage.

Oxidation of lipid and protein is a major reason of flesh quality deterioration during storage. In this work, cold storage (CS) and flake ice (FI) storage, as traditional strategies for live shrimp (Litopenaeus vannamei) sedation and refrigerated storage, showed remarkable oxidation damage of lipid and protein in shrimp flesh during storage. In contrast, ice slurry (IS), with good heat exchange capacity and contactability, stunned shrimp in a sudden and thus relieved antemortem stress, which resulted in reducing the reactive oxygen species and reactive nitrogen species accumulation, and the oxidation damage risk in flesh. Additionally, IS, as a storage medium acted an oxygen barrier, further inhibited the oxidation of lipid and myofibrillar protein (MP), as revealed by the lower thiobarbituric acid reactive substances level, carbonyl (CO) derives content, total disulfide bond (S-S) content, and the higher total sulfhydryl (SH) content in shrimp flesh during storage, compared with CS and FI. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis electrophoretogram pattern of MP also suggested better preservation of myosin heavy chain, myosin light chain, actin, and tropomyosin in IS, whereas these proteins degraded in CS and FI. Consequently, IS prevented the formation of cross-linking caused by oxidation in MP, leading to improved shrimp flesh quality during refrigerated storage, as demonstrated by the better maintained hardness, springiness, and water-holding capacity compared to CS and FI.

Pickering emulsion stabilized by parasin I and chitosan nanoparticles enhances protection against intestinal microbiota homeostasis by reducing inflammation in peritonitis mice.

Although various researches evaluated the stability and drug loading efficiency of chitosan Pickering emulsion, few studies assessed the role and mechanism of emulsions in gut flora homeostasis. Thus, in the basics of our previously published natural and antimicrobial Pickering emulsions, the function of emulsion on the intestinal microbiota and inflammation response was explored in Kunming mice with peritonitis. The results showed that lipid/peptide nanoparticles emulsion (LPNE) and the chitosan peptide-embedded nanoparticles emulsion (CPENE) presented less collagen fiber than parasin I in peritoneal tissue, and CPENE could reduce peritoneal inflammation by decreasing the expression of NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3). The CPENE showed better histological morphology with a smaller fibrosis area in the spleen. Moreover, CPENE, LPNE, and parasin I-conjugated chitosan nanoparticle emulsion (PCNE) groups can increase the abundance of ABC transporters, DNA repair, and recombination proteins, and improve gut microbial. Furthermore, the Pickering emulsion showed a better protection effect on the composition and function of intestinal microbiota by decreasing interleukin-1ß secretion and assembly of the inflammasome of NLRP3. These results could provide evidence for intestinal microbiota homeostasis of chitosan Pickering emulsion in inflammation-related diseases.

Microencapsulation of tomato seed oil using phlorotannins-adducted pea protein isolate-chitosan and pea protein isolate-chitosan complex coacervates.

Pea protein isolates (PPI)/phlorotannins (PT)/chitosan (CS) ternary complex and PPI/CS binary complex were synthesized to prepare tomato seed oil (TSO) microcapsules. The concentration of PT was determined to be 0.025% (w/w) based on the solubility, emulsification, and UV-visible spectrum of PPI-PT complex. Subsequently, the optimal pHs associated with the formation of PPI/CS and PPI-PT/CS complex coacervates were determined to be pH 6.6 and 6.1, while the optimal ratios were 9:1 and 6:1, respectively. The coacervate microcapsules were successfully produced by freeze-dried method and those formulated with PPI-PT/CS displayed significantly lower surface oil content (14.57 ± 0.22%), higher encapsulation efficiency (70.54 ± 0.13%), lower particle size (5.97 ± 0.16 µm), and PDI (0.25 ± 0.02) than PPI/CS. The microcapsules were characterized by scanning electron microscopy and Fourier Transform infrared spectroscopy. Furthermore, the encapsulated TSO exhibited enhanced thermal and oxidative stability than that of free oil, along with microcapsules fabricated with PPI-PT/CS ternary complex showed better protection than that of free PT. Overall, PPI-PT/CS complex as an effective wall material in delivery system presented great potential.

Xanthine Oxidase Inhibitory Peptides from Larimichthys polyactis: Characterization and In Vitro/In Silico Evidence.

Hyperuricemia is linked to a variety of disorders that can have serious consequences for human health. Peptides that inhibit xanthine oxidase (XO) are expected to be a safe and effective functional ingredient for the treatment or relief of hyperuricemia. The goal of this study was to discover whether papain small yellow croaker hydrolysates (SYCHs) have potent xanthine oxidase inhibitory (XOI) activity. The results showed that compared to the XOI activity of SYCHs (IC50 = 33.40 ± 0.26 mg/mL), peptides with a molecular weight (MW) of less than 3 kDa (UF-3) after ultrafiltration (UF) had stronger XOI activity, which was reduced to IC50 = 25.87 ± 0.16 mg/mL (p < 0.05). Two peptides were identified from UF-3 using nano-high-performance liquid chromatography-tandem mass spectrometry. These two peptides were chemically synthesized and tested for XOI activity in vitro. Trp-Asp-Asp-Met-Glu-Lys-Ile-Trp (WDDMEKIW) (p < 0.05) had the stronger XOI activity (IC50 = 3.16 ± 0.03 mM). The XOI activity IC50 of the other peptide, Ala-Pro-Pro-Glu-Arg-Lys-Tyr-Ser-Val-Trp (APPERKYSVW), was 5.86 ± 0.02 mM. According to amino acid sequence results, the peptides contained at least 50% hydrophobic amino acids, which might be responsible for reducing xanthine oxidase (XO) catalytic activity. Furthermore, the inhibition of the peptides (WDDMEKIW and APPERKYSVW) against XO may depend on their binding to the XO active site. According to molecular docking, certain peptides made from small yellow croaker proteins were able to bind to the XO active site through hydrogen bonds and hydrophobic interactions. The results of this work illuminate SYCHs as a promising functional candidate for the prevention of hyperuricemia.

Improving the biological activities of astaxanthin using targeted delivery systems.

The antioxidant and anti-inflammatory properties of astaxanthin (AST) enable it to protect against oxidative stress-related and inflammatory diseases with a range of biological effects. These activities provide the potential to develop healthier food products. Therefore, it would be beneficial to design delivery systems for AST to overcome its low stability, control its release, and/or improve its bioavailability. This review discusses the basis for AST's various biological activities and the factors limiting these activities, including stability, solubility, and bioavailability. It also discusses the different systems available for the targeted delivery of AST and their applications in enhancing the biological activity of AST. These include systems that are candidates for preventive and therapeutic effects, which include nerves, liver, and skin, particularly for possible cancer reduction. Targeted delivery of AST to specific regions of the gastrointestinal tract, or more selectively to target tissues and cells, can be achieved using targeted delivery systems to increase the biological activities of AST.

Effects of magnetic nanoscale combined radio frequency or microwave thawing on conformation of sea bass myosin heavy chain: a molecular dynamics study.

BACKGROUND: The consumption of frozen foods inevitably involves a thawing process. Protein conformation changes during a short thawing process and the quantification of their effects remains challenging. Molecular dynamics simulations can be used to evaluate the conformational changes of protein occurring in food processing. RESULTS: In the present study, four different thawing methods were used [i.e. magnetic nanometer combined with microwave thawing (MT-Mag), magnetic nanometer combined with radio frequency thawing (RT-Mag), radio frequency thawing (RT) and microwave thawing (MT)] to change the conformation of myosin heavy chain (MHC). The results obtained showed that, compared with the fresh sample, the hydrogen bond number and radius of gyration of the RT-Mag and RT groups were less decreased. Visual molecular dynamics STRIDE analysis showed that the content of the α helix was relatively high in the RT-Mag and MT-Mag groups. CONCLUSION: These simulation results indicate that RT-Mag can be used as an effective method for promoting the thawing process of fish and better stabilizing the protein structure. These conclusions provide a theoretical realization for understanding the protein conformational transition during the thawing process and the realization of quantification and also provide guidance for choosing better thawing conditions without loss of nutritional properties. © 2022 Society of Chemical Industry.

Application of Cyclocarya paliurus-Kiwifruit Composite Fermented to Enhance Antioxidant Capacity, Flavor, and Sensory Characteristics of Kiwi Wine.

A new fermentation method for kiwi wine was explored by developing the well-known medicinal and edible plant Cyclocarya paliurus (C. paliurus) to create more value with undersized kiwifruits. In this study, the changes in bioactive substances during the C. paliurus-kiwi winemaking process were analyzed on the basis of response surface optimization results, and the antioxidant capacity, aromatic compounds, and sensory quality of the C. paliurus-kiwi composite wine with kiwi wine and two commercial kiwi wines were compared. The results showed that DPPH radical, OH- radical, and ABTS+ scavenging rates remained at over 60.0%, 90.0%, and 70.0% in C. paliurus-kiwi wine, respectively. The total flavonoid content (TFC) and total polyphenol content (TPC) of C. paliurus-kiwi wine were significantly higher than those of the other three kiwi wines. C. paliurus-kiwi wine received the highest score and detected 43 volatile compounds. Ethyl hexanoate, which showed stronger fruity and sweet aromas, was one of the main aroma components of C. paliurus-kiwi wine and different from commercial wines. This wine has a good flavor with a natural and quality feeling of C. paliurus-kiwifruit extract, low-cost processing, and great market potential.

Nanoparticle Emulsions Enhance the Inhibition of NLRP3.

Antibacterial delivery emulsions are potential materials for treating bacterial infections. Few studies have focused on the role and mechanism of emulsions in inflammation relief. Therefore, based on our previous analysis, in which the novel and natural Pickering emulsions stabilized by antimicrobial peptide nanoparticles were prepared, the regulation effect of emulsion on inflammasome was explored in silico, in vitro and in vivo. Firstly, the interactions between inflammasome components and parasin I or Pickering emulsion were predicted by molecular docking. Then, the inflammasome stimulation by different doses of the emulsion was tested in RAW 264.7 and THP-1 cells. Finally, in Kunming mice with peritonitis, NLRP3 and IL-1ß expression in the peritoneum were evaluated. The results showed that the Pickering emulsion could combine with ALK, casp-1, NEK7, or NLRP3 to affect the assembly of the NLRP3 and further relieve inflammation. LPNE showed a dose-dependent inhibition effect on the release of IL-1ß and casp-1. With the concentration of parasin I increased from 1.5 mg/mL to 3 mg/mL, the LDH activity decreased in the chitosan peptide-embedded nanoparticles emulsion (CPENE) and lipid/peptide nanoparticles emulsion (LPNE) groups. However, from 1.5 to 6 mg/mL, LPNE had a dose-dependent effect on the release of casp-1. The CPENE and parasin I-conjugated chitosan nanoparticles emulsion (PCNE) may decrease the release of potassium and chloride ions. Therefore, it can be concluded that the LPNE may inhibit the activation of the inflammasome by decreasing LDH activity, potassium and chloride ions through binding with compositions of NLRP3.

Understanding of physicochemical properties and antioxidant activity of ovalbumin-sodium alginate composite nanoparticle-encapsulated kaempferol/tannin acid.

In this research, ovalbumin (OVA) and sodium alginate (SA) were used as the materials to prepare an OVA-SA composite carrier, which protected and encapsulated the hydrophobic kaempferol (KAE) and the hydrophilic tannic acid (TA) (OVA-SA, OVA-TA-SA, OVA-KAE-SA, and OVA-TA-KAE-SA). Results showed that the observation of small diffraction peaks in carriers proved the successful encapsulation of KAE/TA. The protein conformation of the composite nanoparticles changed. OVA-TA-SA composite nanoparticles had the highest α-helix content and the fewest random coils, so the protein structure of it had the strongest stability. OVA-TA-KAE-SA composite nanoparticles had the strongest system stability and thermal stability, which might be due to the synergistic effect of the two polyphenols, suggesting the encapsulation of KAE/TA increased the system stability and the thermal stability of OVA-SA composite nanoparticles. Additionally, the composite nanoparticles were endowed with antioxidant ability and antibacterial ability (against Staphylococcus aureus and Escherichia coli) in the order OVA-TA-SA > OVA-TA-KAE-SA > OVA-KAE-SA based on the difference in antibacterial diameter (D, mm) and square (S, mm2), indicating that polyphenols enhanced the antibacterial and antioxidant ability of OVA-SA composite nanoparticles, and the enhancement effect of TA was stronger than that of KAE. These results provide a theoretical basis for the application of OVA-SA composite nanoparticles in the delivery of bioactive compounds.

Influence of polyphenol-metal ion-coated ovalbumin/sodium alginate composite nanoparticles on the encapsulation of kaempferol/tannin acid.

In this research, ovalbumin (OVA) and sodium alginate (SA) were used as the materials to prepare OVA-SA composite carriers, which protected and encapsulated the hydrophobic kaempferol (KAE) and the hydrophilic tannic acid (TA). To achieve the purpose of targeted delivery, the TA-Fe3+ coating film was prepared. Results showed that the observation of small diffraction peaks in carriers proved the formation of TA/Fe3+ coating film on the surface of four composite nanoparticles (pOVA, pOVA-SA, pOVA-KAE-SA, and pOVA-KAE-TA-SA). The protein structure of the composite nanoparticles coated with TA/Fe3+ changed, and the order of the changes was pOVA-KAE > pOVA > pOVA-KAE-SA > pOVA-KAE-TA-SA > pOVA-SA. This phenomenon is due to the fact that the chromophore -C=O and the auxo-chromophore -OH are in the opposite position in the benzene ring of TA, and the two substituents have opposite effects and synergize, resulting in the different degrees of redshift of the composite nanoparticle λmax. Additionally, pOVA-SA had the highest α-helix content and the lowest random coils, conferring the protein structure the strongest stability. The coating of TA/Fe3+ increased the system stability and the thermal stability of the composite nanoparticles. Additionally, the carriers were endowed with antioxidant activity, and their antibacterial ability against Staphylococcus aureus and Escherichia coli was pOVA-KAE-TA-SA > pOVA-KAE-SA > pOVA-KAE > pOVA-SA > pOVA based on the difference in antibacterial diameter (D, mm) and square (S, mm2). pOVA-KAE-TA-SA had the strongest antioxidant activity and antibacterial ability, which improved the bioavailability of TA/KAE. These results provide a theoretical basis for the application of OVA-SA composite nanoparticles in the delivery of bioactive compounds.

Preparation, characterization of naringenin, ß-cyclodextrin and carbon quantum dot antioxidant nanocomposites.

In this work, naringenin loaded ß-cyclodextrin and carbon quantum dots composite nanoparticles were successfully fabricated. The results showed that incorporation of carbon quantum dots not only enhanced antioxidant activities of nanoparticles but also improved encapsulation efficiency of naringenin. Further, the formation of composite nanoparticles was confirmed by a series of characterization methods. The zeta-potential and Fourier transform infrared spectroscopy data proved that electrostatic interaction and hydrogen bonding are dominant forces to form nanoparticles. X-Ray Diffraction experiment revealed that the material state of the formed naringenin-ß-CD-CQDs nanoparticles is amorphous in opposition to the crystalline state of naringenin, ß-CD and naringenin-ß-CD inclusion complex. Finally, antioxidant activity analyses against DPPH, ABTS+ and Fe2+ chelating, showed an enhanced antioxidant activity of the formed composite nanoparticles compared to their constituents. These results indicated that naringenin can be effectively entrapped in ß-cyclodextrin and carbon quantum dots, forming composite nanoparticles with improved antioxidant properties.

The gut microbiota as a target to control hyperuricemia pathogenesis: Potential mechanisms and therapeutic strategies.

Hyperuricemia (HUA) is a metabolic disorder caused by abnormal uric acid (UA) metabolism, which is a complex physiological process involving multiple organs (liver, kidney, and intestine). Although UA metabolism in the liver and kidneys has been elucidated, only a few studies have focused on the process in the intestine. With our growing knowledge of the effects of gut microorganisms on health, the gut microbiota has been identified as a new target for HUA treatment. In this review, the relationship between HUA and the gut microbiota is elucidated, and anti-hyperuricemia mechanisms targeting the intestine are discussed, such as the promotion of purine and UA catabolism by the gut microbiota, increases in UA excretion by the gut microbiota and its metabolites, regulation of UA absorption or secretion in the intestinal tract by certain transporters, and the intestinal inflammatory response to the gut microbiota. Additionally, probiotics (Bifidobacteria and Lactobacilli) and prebiotics (polyphenols, peptides, and phytochemicals) with UA-lowering effects targeting the intestinal tract are summarized, providing reference and guidance for further research.

Integrated metabolomic and gene expression analyses to study the effects of glycerol monolaurate on flesh quality in large yellow croaker (Larimichthys crocea).

To improve the quality of cultured large yellow croaker (Larimichthys crocea), this study was performed to study the impacts of glycerol monolaurate (GML) on the nutritional value, growth performance, muscle texture, and taste intensity of L. crocea. The results showed that GML as a feed additive significantly increased the crude lipid content and reduced the diameters of muscle fibers, which in turn markedly altered the flesh texture in terms of cohesiveness. Moreover, the taste indicators (umami and richness) and flavor-related amino acid (glutamic acid, glycine, and proline) contents of L. crocea muscle were significantly higher in the GML group. Metabolomic and gene expression analyses showed that GML supplementation could significantly improve amino acid biosynthesis and metabolism, promote protein and lipid synthesis, and activate myogenic-related signaling pathways of L. crocea. Consequently, adding an appropriate amount of GML to fish feed would be conducive to providing healthy, nutrient-rich and acceptably flavored aquatic-products.

Preparation and physicochemical stability of tomato seed oil microemulsions.

In this study, microemulsions were fabricated using tomato seed oil, water, Tween 80 and citric acid, and then the physicochemical characteristics and the influence of environmental stress were investigated. The physicochemical properties of the microemulsions were evaluated by transmission electron microscopy (TEM), mean particle diameter, polydispersity index (PDI) and conductivity. The phase diagrams of tomato seed oil/Tween 80/citric acid/water microemulsions were constructed under different pHs and ionic strengths. Storage stability of the systems was investigated at 4, 37 and 65°C, and changes in turbidity and lipid oxidation products were monitored. Nano-size zeta potential analyzer results demonstrated that the mean particle diameter and polydispersity index of tomato seed oil microemulsions were 14 nm and 0.014. The transition from W/O to O/W could be detected from electrical conductivity and viscosity data with the increasing of water content. The results showed that the microemulsion areas decreased with increasing pH and NaCl concentrations. What is more, the study proved that tomato seed oil microemulsions exhibited a good storage stability. PRACTICAL APPLICATION: In this study, the preparation of tomato seed oil microemulsion can not only make full use of the nutritional value of tomato seed oil, but also ensure the effective protection of the nutrients contained in it, and improve the problem of adding difficult. By using microemulsion as delivery carrier of tomato seed oil, the application of tomato seed oil in food, cosmetics and other fields could be enhanced. Therefore, the preparation of tomato seed oil microemulsion provides a theoretical basis for production practice.

Assessing the Effects of Ginger Extract on Polyphenol Profiles and the Subsequent Impact on the Fecal Microbiota by Simulating Digestion and Fermentation In Vitro.

The beneficial effects of ginger polyphenols have been extensively reported. However, their metabolic characteristics and health effects on gut microbiota are poor understood. The purpose of this study was to investigate the digestion stability of ginger polyphenols and their prebiotic effects on gut microbiota by simulating digestion and fermentation in vitro. Following simulated digestion in vitro, 85% of the polyphenols were still detectable, and the main polyphenol constituents identified in ginger extract are 6-, 8-, and 10-gingerols and 6-shogaol in the digestive fluids. After batch fermentation, the changes in microbial populations were measured by 16S rRNA gene Illumina MiSeq sequencing. In mixed-culture fermentation with fecal inoculate, digested ginger extract (GE) significantly modulated the fecal microbiota structure and promoted the growth of some beneficial bacterial populations, such as Bifidobacterium and Enterococcus. Furthermore, incubation with GE could elevate the levels of short-chain fatty acids (SCFAs) accompanied by a decrease in the pH value. Additionally, the quantitative PCR results showed that 6-gingerol (6G), as the main polyphenol in GE, increased the abundance of Bifidobacterium significantly. Therefore, 6G is expected to be a potential prebiotic that improves human health by promoting gut health.

Effects of different thawing methods on conformation and oxidation of myofibrillar protein from largemouth bass (Micropterus salmoides).

This study examined the effects on conformation and oxidation of myofibrillar protein in largemouth bass by different thawing methods. The conventional thawing, microwave thawing, microwave (MVT) or ultrasound combined with vacuum thawing, microwave or far-infrared thawing (FMT) combined with magnetic nanoparticles were used in this experiment. The physicochemical changes were analyzed by differential scanning calorimetry and dynamic rheology. The protein structure changes were measured by Raman, intrinsic fluorescence, and second-derivative ultraviolet spectrometry. The degree of protein aggregation was evaluated by surface hydrophobicity, particle size, and zeta-potential measurements. Total sulfhydryl content, protein carbonyl content, Ca2+ -ATPase activity, and SDS-PAGE were used to analyze the degree of protein oxidation. Results showed that MVT and FMT samples had better thermal stability, more stable protein conformation, and a lower degree of protein oxidation. Thus, these two methods would be beneficial to sustain the quality of thawed fillets. PRACTICAL APPLICATIONS: In the market circulation, largemouth bass (Micropterus salmoides) need to be frozen. The thawing methods can directly affect the quality of frozen fish, thus causing the changes in the conformation of the myofibrillar protein in fish, and also affecting the degree of protein oxidation. The results showed that the microwave combined with vacuum and the magnetic nanoparticles combined with far-infrared thawing had less effect on myofibrillar protein of fish and were a better thawing method.

Slow-Release and Nontoxic Pickering Emulsion Platform for Antimicrobial Peptide.

The resistance in microorganisms against many conventional antibiotics has become a serious global health problem. However, antibacterial drug delivery materials are still limited in toxicity, short efficacy and reducing inflammation. The novel and natural Pickering emulsions stabilized by antimicrobial peptide nanoparticles were tested as promising platforms to control bacterial resistance development. The parasin I interacted or conjugated with lecithin or chitosan and formed nanoparticles encapsulated by Pickering emulsion. The protonation and deprotonation of amino groups in chitosan and parasin I resulted in nanoparticles in different aggregate states and changed emulsion stability. Moreover, the Pickering emulsion could induce severe bacterial agglomeration on both Gram-positive and Gram-negative bacteria than parasin I through the membrane disintegration mechanism. Furthermore, the Pickering emulsion could alleviate the cytotoxicity of human liver cells and hemolytic activity in rat blood cells. In combination with the lack of acute cytotoxicity in Kunming mice and milder, more effective anti-inflammatory effect in peritonitis demonstrated for these Pickering emulsions, especially chitosan peptide-embedded nanoparticles Pickering emulsion, a potential role in combating multidrug resistant bacteria in biomedical applications.

The effects of CS@Fe3O4 nanoparticles combined with microwave or far infrared thawing on microbial diversity of red seabream (Pagrus major) fillets based on high-throughput sequencing.

The present study investigated the effects of CS@Fe3O4 nanoparticles combined with microwave or far infrared thawing on microbial diversity of red seabream (Pagrus major) fillets in terms of thawing loss, pH, TVB-N, classical microbiological enumeration and high-throughput sequencing, and the same parameters were also studied for 24 h after thawing. Four thawing methods were used: microwave thawing (MT), far-infrared thawing (FT), CS@Fe3O4 nanoparticles combined with microwave thawing (CMT) and CS@Fe3O4 nanoparticles combined with far-infrared thawing (CFT). The results showed that CFT and CMT had lower values of pH and TVB-N compared to the FT and MT. Based on conventional microbial count analysis, CFT and CMT samples also maintained lower TVC, pseudomonas and LAB counts. Using high-throughput sequencing analysis, Compared with FT and MT, CFT and CMT samples showed a significant decrease in the proportion of the Pseudomonadaceae flora. However, the proportion of Pseudomonas, Bacillaceae and Thermaceae also increased significantly after 24 h of storage, which indicated that become the predominant microbiota in red seabream (Pagrus major) fillets.