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.

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.

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.

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.

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.

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.

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.

Effect of ultrasonic thawing on the water-holding capacity, physicochemical properties and structure of frozen tuna (Thunnus tonggol) myofibrillar proteins.

BACKGROUND: The effect of ultrasonic thawing (0, 160, 280, 400 W) on water-holding capacity (WHC), physicochemical properties and structure of tuna myofibrillar proteins was investigated. RESULTS: Thawing time was shown to decrease and thawing loss to increase significantly (P < 0.05) as power increased (160-400 W), whereas there was no significant difference (P > 0.05) in cooking loss. Changes in T2 relaxation time were investigated using low-field nuclear magnetic resonance. Ultrasonic thawing could significantly (P < 0.05) improve the immobilised water content compared to the control (0 W). surface hydrophobicity decreased significantly and then increased significantly (P < 0.05), whereas there was no significant difference (P > 0.05) in the reactive sulfhydryl content as power was increased. Tuna thawed at 280 W suffered fewer negative effects on its microstructure. Roman spectral date showed that the α-helix changed to a random coil and ß-turn as power was increased (up to 400 W). CONCLUSION: The application of ultrasonic thawing at a specified power was showed to be a beneficial process when used in the seafood industry, but application of excessive power resulted in lower WHC and structural changes to myofibrillar proteins. © 2019 Society of Chemical Industry.

Recent Advances in Food Thawing Technologies.

Serious quality deterioration can occur with suboptimal thawing, and thus innovative thawing technologies may have an important role in improving the final quality of frozen foods. In recent years, although several new thawing technologies have been extensively studied, such as ultra-high pressure assisted thawing, ultrasound-assisted thawing, high-voltage electrostatic field thawing, ohmic thawing, and radio frequency thawing, more research is needed to make them more applicable to thawing of food industrially. A better evaluation of the impact of thawing is needed to help move new thawing technologies forward. This review discusses the principles involved, the applications to different types of foods, modeling of the various processes, new evaluation techniques, and patents obtained for the different systems. The benefits and weaknesses of these systems are also discussed to provide a more complete review of these new thawing techniques. This review will, hopefully, encourage additional work that may help reach the goal of having better food thawing systems.

Comparative study on acid-soluble and pepsin-soluble collagens from skin and swim bladder of grass carp (Ctenopharyngodon idella).

BACKGROUND: Collagen has a wide range of applications in food, biomedical and pharmaceutical products. RESULTS: The collagens in grass carp (Ctenopharyngodon idella) skin and swim bladder were extracted using acetic acid and pepsin. Higher yield of pepsin-soluble collagen (PSC) was obtained from skin (178 g kg(-1)) than from swim bladder (114 g kg(-1)). Not surprisingly, yields of PSC from skin and swim bladder were also higher than those of acid-soluble collagen (ASC) from the same organs (89 and 51 g kg(-1)). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profiles showed that ASC and PSC were type I collagens, with PSC containing a higher proportion of α components than ASC. Fourier transform infrared spectra revealed that ASC and PSC were very similar in their protein secondary structures. Scanning electron micrographs showed that the collagens had a spongy structure, with more pores being obtained in swim bladder than in skin collagens. The collagens showed high solubility in the acidic pH range. However, their solubility decreased in the presence of NaCl at concentrations above 20 g kg(-1). CONCLUSION: Collagens were successfully extracted from the skin and swim bladder of grass carp. These fish by-products could serve as an alternative source of collagens for a wide variety of applications in the food and nutraceutical industries.

Effect of egg albumen protein addition on physicochemical properties and nanostructure of gelatin from fish skin.

The physicochemical properties and nanostructure of mixtures of egg albumen protein (EAP) and gelatin from under-utilised grass carp (Ctenopharyngodon idella) skins were studied. The gelatin with 1% EAP had an acceptable gel strength. The addition of 5% EAP significantly increased the melting and gelling temperatures of gelatin gels. Additionally, the colour turned white and the crystallinity was higher in gelatin gels with gradient concentrations of EAP (1, 3, and 5%). Gelatin with 5% EAP had the highest G' values while gelatin with 1% EAP had the lowest G' values. Atomic force microscopy showed the heterogeneous nanostructure of fish gelatin, and a simple coacervate with a homogeneous distribution was only observed with the addition of 1% EAP, indicating interaction between gelatin and EAP. These results showed that EAP effect fish gelatin's physicochemical and nanostructure properties and has potential applications in foods and pharmaceuticals.

Isolation and characterisation of Bacillus spp. antagonistic to Vibrio parahaemolyticus for use as probiotics in aquaculture.

Acute gastroenteritis caused by pathogenic Vibrio parahaemolyticus is one of the major factors affecting the development of aquaculture and the safety of seafood. Using the antagonism of probiotics against pathogens is an alternative strategy to antibiotics and a common trend to control food-borne pathogenic bacteria. In this study, a total of 249 isolates were isolated from four types of seafood (Litopenaeus vannamei, Oratosquilla oratoria, Mactra veneriformis and Portunus trituberculatus) and coastal sediment from Liaodong Bay in the Bohai Sea, China with five different separation agars. The most isolates came from the sample of coastal sediment and on agar of 2216E, which accounted for 36.14 and 54.62 % respectively. Twenty-four among 249 isolates displayed direct antimicrobial activity to V. parahaemolyticus with spot inoculation. Sixteen active isolates were selected for extracellular antimicrobial activity using the Oxford cup method. Only strains of B16 and J7 showed extracellular antimicrobial activity and were identified as Bacillus pumilus and Bacillus mojavensis respectively based on the physiological identification and 16S rRNA sequence analysis. Both of the strains B16 and J7 exhibited extracellular hydrolytic enzyme activity and antagonism against more than one indicator bacteria in vitro, which indicates that the two strains have broad potential application as suitable probiotic candidates in aquaculture while B. mojavensis was first reported to inhibit pathogenic Vibrio spp. in vitro. There is no particular trait as to antagonism of B. pumilus B16 or B. mojavensis J7 to Gram-positive or Gram-negative indicator bacteria.

The neuroprotective and antioxidant activities of protein hydrolysates from grass carp (Ctenopharyngodon idella) skin.

To observe the neuroprotective and antioxidant activities of the grass carp protein hydrolysates (GPH) obtained from grass carp (Ctenopharyngodon idella) skin by enzymatic hydrolysis. GPH prepared using Protamex, at different (5, 10, 15, 20 and 30 %) degrees of hydrolysis (DH) were investigated. The DPPH radial scavenging, reducing power and inhibition of linoleic acid oxidation activities of GPH were significantly improved by a low DH (5 %) compared with those of GPH with a higher DH (p < 0.05). A low degree of enzymatic hydrolysis was appropriate to obtain GPH with improved neuroprotective activities. These results suggest that the control of the DH may be an effective strategy to modify specific neuroprotective and antioxidant activities of GPH, and GPH has potential as a functional food ingredient for related functional and health benefits.

Thawing of Frozen Hairtail (Trichiurus lepturus) with Graphene Nanoparticles Combined with Radio Frequency: Variations in Protein Aggregation, Structural Characteristics, and Stability.

Efficient thawing can preserve the quality of frozen hairtail (Trichiurus lepturus) close to that of fresh hairtail. In contrast to air thawing (AT) and radio-frequency thawing (RT), this study looked at how graphene oxide (GO) and graphene magnetic (GM) nanoparticles paired with RT affect the microstructure and protein conformation of hairtails after thawing. The results suggested that GM-RT can reduce the myofibrillar protein (MP) damage and be more effective than other thawing treatments, like AT, RT, and GO-RT, in maintaining the microstructure of hairtail. The particle size and zeta potential showed that GM-RT could reduce the aggregation of MP during the thawing process compared to other thawing methods. Moreover, the texture of the hairtail after GM-RT exhibited higher hardness (1185.25 g), elasticity (2.25 mm), and chewiness (5.75 mJ) values compared to other thawing treatments. Especially compared with RT, the GM-RT treatment displayed significant improvements in hardness (27.24%), a considerable increase in springiness (92.23%), and an increase in chewiness (57.96%). GO-RT and GM-RT significantly reduced the centrifugal loss. The scanning electron microscopy results demonstrated that the effect of GM-RT was more akin to that of a fresh sample (FS) and characterized by a well-organized microstructure. In conclusion, GM-RT effectively diminished the MP aggregation and improved the texture of thawed fish. It can be regarded as a viable alternative thawing technique to enhance MP stability, which is vital for preserving meat quality.

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.

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.

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.

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.

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.