Controllable construction of ZIF-derived Co9S8 hollow polyporous polyhedrons with Ru-doping for enhanced hydrogen evolution reaction.

Ru-doped Co9S8 hollow porous polyhedrons (Ru-Co9S8 HPPs) derived from zeolitic-imidazolate-frameworks were synthesized through hydrothermal coprecipitation and thermal decomposition methods. The results indicate that Ru-Co9S8-500 HPPs possess a strong Ru-Co synergistic effect, large electrochemical surface area, and sufficient active sites, endowing them with excellent hydrogen evolution reaction performance.

Glycogen and zinc-enriched ferritin as bioavailable nanoparticulate nutrients released from gastrointestinal digestion of pacific oyster (Crassostrea gigas).

Oyster is a low-carbon animal food enriched with protein, glycogen, and trace minerals. Nano-nutrients are increasingly perceived as an unignorable part of foods. Here, simulated gastrointestinal digestion released a considerable amount of nanoparticulate nutrients from raw and cooked oysters. They were identified as glycogen monomers with size of 20-40 nm and their aggregates, as well as 6 nm-sized bare cores of ferritin containing iron and zinc (4:1, w/w). FITC-labeling and flow cytometry unveiled the efficient uptake of oyster glycogen by polarized Caco-2 cells via macropinocytosis and receptor-mediated endocytosis. Calcein-fluorescence-quenching assay revealed divalent-metal-transporter-1- and macropinocytosis-mediated enterocyte iron absorption from oyster ferritin. Zinquin-fluorescence flow cytometry and ex-vivo mouse ileal loop experiments demonstrated the ready intestinal zinc absorption from oyster ferritin via macropinocytosis, as well as the good resistance of oyster ferritin to phytate's inhibition on zinc absorption. Overall, our results offer a new insight into the digestive and chemical properties of oysters.

Microalgae polyphosphate nanoparticles deliver bioavailable calcium against phytate antagonism: Ex vivo and in vivo studies.

Biogenic nanoparticles are promising carriers to deliver essential minerals. Here, calcium-enriched polyphosphate nanoparticles (CaPNPs) with a Ca/P molar ratio > 0.5 were produced by Synechococcus sp. PCC 7002 in the growth medium containing 1.08 g/L CaCl2, and had nearly spherical morphologies with a wide size distribution of 5-75 nm and strongly anionic surface properties with an average ζ-potential of -39 mV, according to dynamic light-scattering analysis, transmission and scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The ex-vivo ligated mouse ileal loop assays found that calcium in CaPNPs was readily available to intestinal absorption via both ion channel-mediated and endocytic pathways, specifically invoking macropinocytic internalization, lysosomal degradation, and transcytosis. Rat oral pharmacokinetics revealed that CaPNPs had a calcium bioavailability approximately 100 % relative to that of CaCl2 and more than 1.6 times of that of CaCO3. CaPNPs corrected the retinoic acid-induced increase in serum calcium, phosphorus, and bone-specific alkaline phosphatase, and decrease in serum osteocalcin, bone mineral content/density, and femoral geometric parameters with an efficacy equivalent to CaCl2 and markedly greater than CaCO3. In contrast to CaCl2, CaPNPs possessed desirable resistance against phytate's antagonistic action on calcium absorption in these ex vivo and in vivo studies. Overall, CaPNPs are attractive as a candidate agent for calcium supplementation, especially to populations on high-phytate diets.

A novel variant of PLA2G6 gene related early-onset parkinsonism: a case report and literature review.

This study reported a case of early-onset parkinsonism associated with a novel variant of the PLA2G6 gene. The boy first started showing symptoms at the age of 11, with gait instability and frequent falls. As the disease progressed, his gait instability worsened, and he developed difficulties with swallowing and speaking, although there was no apparent decline in cognitive function. An MRI of the head revealed significant atrophy of the cerebellum. The initial diagnosis for the boy was early-onset parkinsonism, classified as Hoehn-Yahr grade 5.Genomic sequencing of the patient indicated that he had compound heterozygous variations in the PLA2G6 gene: c.1454G>A (p.Gly485Glu) and c.991G>T (p.Asp331Tyr). Pedigree analysis revealed that his younger brother also carried the same variant, albeit with milder symptoms. The patient's unaffected mother was found to be a carrier of the c.991G>T variant. Additionally, this study reviewed 62 unrelated families with PLA2G6 gene-related early-onset parkinsonism. The analysis showed a higher proportion of female probands, with a mean age of onset of ~23.0 years. Primary symptoms were predominantly bradykinesia and psychosis, with tremors being relatively rare. Cerebellar atrophy was observed in 41 patients (66.1%). Among the reported mutations, the most common mutation was c.991G>T, presenting in 21 families (33.9%), followed by c.2222G>A in eight families (12.9%). Other mutations were less common. Notably, the c.991G>T mutation was exclusive to Chinese families and was a prevalent mutation among this population. The initial symptoms varied significantly among patients with different mutations.

Enhanced biomass production and harvesting efficiency of Chlamydomonas reinhardtii under high-ammonium conditions by powdered oyster shell.

Chlamydomonas reinhardtii prefers ammonium (NH4+) as a nitrogen source, but its late-stage growth under high-NH4+ concentrations (0.5 âˆ¼ 1 g/L) is retarded due to medium acidification. In this study, oyster shell powders were shown to increase the tolerance of C. reinhardtii to NH4+ supplementation at 0.7 g/L in TAP medium in 1-L bubble-column bioreactors, resulting in a 22.9 % increase in biomass production, 62.1 % rise in unsaturated fatty acid accumulation, and 19.2 % improvement in harvesting efficiency. Powdered oyster shell mitigated medium acidification (pH 7.2-7.8) and provided dissolved inorganic carbon up to 8.02 × 103 µmol/L, facilitating a 76.3 % NH4+ consumption, release of up to 189 mg/L of Ca2+, a 42.1 % reduction in ζ-potential and 27.7 % increase in flocculation activity of microalgae cells. This study highlights a promising approach to utilize powdered oyster shell as a liming agent, supplement carbon source, and bio-flocculant for enhancing biomass production and microalgae harvesting in NH4+-rich environments.

Heterosynaptic plasticity of the visuo-auditory projection requires cholecystokinin released from entorhinal cortex afferents.

The entorhinal cortex is involved in establishing enduring visuo-auditory associative memory in the neocortex. Here we explored the mechanisms underlying this synaptic plasticity related to projections from the visual and entorhinal cortices to the auditory cortex in mice using optogenetics of dual pathways. High-frequency laser stimulation (HFS laser) of the visuo-auditory projection did not induce long-term potentiation. However, after pairing with sound stimulus, the visuo-auditory inputs were potentiated following either infusion of cholecystokinin (CCK) or HFS laser of the entorhino-auditory CCK-expressing projection. Combining retrograde tracing and RNAscope in situ hybridization, we show that Cck expression is higher in entorhinal cortex neurons projecting to the auditory cortex than in those originating from the visual cortex. In the presence of CCK, potentiation in the neocortex occurred when the presynaptic input arrived 200 ms before postsynaptic firing, even after just five trials of pairing. Behaviorally, inactivation of the CCK+ projection from the entorhinal cortex to the auditory cortex blocked the formation of visuo-auditory associative memory. Our results indicate that neocortical visuo-auditory association is formed through heterosynaptic plasticity, which depends on release of CCK in the neocortex mostly from entorhinal afferents.

Gum Arabic-Derived Hydroxyproline-Rich Peptides Stimulate Intestinal Nonheme Iron Absorption via HIF2α-Dependent Upregulation of Iron Transport Proteins.

The stimulation of host iron absorption is a promising antianemia strategy adjunctive/alternative to iron intervention. Here, gum arabic (GA) containing 3.14 ± 0.56% hydroxyproline-rich protein with repetitive X-(Pro/Hyp)n motifs was found to increase iron reduction, uptake, and transport to upregulate duodenal cytochrome b (Dcytb), divalent metal transporter 1 (DMT1), ferroportin, and hephaestin to inhibit hypoxia-inducible factor (HIF) prolyl hydroxylase (PHD) and to stabilize HIF2α in polarized Caco-2 cell monolayers in a dose-dependent manner, and this was dependent on its protein fraction, rather than the polysaccharide fraction. Three abundant GA-derived hydroxyproline-containing dipeptides of Hyp-Hyp, Pro-Hyp, and Ser-Hyp were detected by liquid chromatography-mass spectrometry in the lysates of polarized Caco-2 cell monolayers at the maximum levels of  0.167 ± 0.021, 0.134 ± 0.017, and 0.089 ± 0.015 µg/mg of protein, respectively, and showed desirable docking affinity energy values of -7.53, - 7.91, and -7.39 kcal/mol, respectively, against human PHD3. GA-derived peptides also acutely increased duodenal HIF2α stability and Dcytb, DMT1, ferroportin, and hephaestin transcription in rats (P < 0.05). Overall, GA-derived hydroxyproline-rich peptides stimulated intestinal iron absorption via PHD inhibition, HIF2α stabilization, and subsequent upregulation of iron transport proteins.

Caseinophosphopeptides Overcome Calcium Phytate Inhibition on Zinc Bioavailability by Retaining Zinc from Coprecipitation as Zinc/Calcium Phytate Nanocomplexes.

Caseinophosphopeptides have shown great potential to increase zinc bioavailability from phytate-rich diets, but the mechanism of action remains unclear. Here, caseinophosphopeptides from a sodium caseinate hydrolysate dose-dependently retained zinc in solution against calcium phytate coprecipitation under physiologically relevant conditions. The 3 kDa ultrafiltration separation unveiled no added low-molecular-weight chelates of zinc and calcium by caseinophosphopeptides. Tyndall effect, dynamic light scattering measurements, transmission electron microscopy observation, electron diffraction pattern, X-ray diffraction spectrum, and energy-dispersive X-ray analysis demonstrated the caseinophosphopeptides-mediated formation of single-crystal zinc/calcium phytate nanocomplexes (Zn/CaPA-NCs) with a size and ζ-potential of 10-30 nm and -25 mV, respectively. Caseinophosphopeptides-stabilized Zn/CaPA-NCs were found to deliver bioavailable nanoparticulate zinc in mouse jejunal loop ex vivo model and polarized Caco-2 cells, and the treatments with specific inhibitors revealed that intestinal zinc absorption from Zn/CaPA-NCs invoked macropinocytosis, lysosomal release into the cytosol, and transcytosis. Overall, our study proposes a new paradigm for the benefit of caseinophosphopeptides for zinc bioaccessibility and bioavailability in phytate-rich diets.

Microalgae polysaccharides exert antioxidant and anti-inflammatory protective effects on human intestinal epithelial cells in vitro and dextran sodium sulfate-induced mouse colitis in vivo.

Microalgae polysaccharides (MAPS) have emerged as novel prebiotics, but their direct effects on intestinal epithelial barrier are largely unknown. Here, MAPS isolated from Chlorella pyrenoidosa, Spirulina platensis, and Synechococcus sp. PCC 7002 were characterized as mainly branched heteropolysaccharides, and were bioavailable to Caco-2 cells based on fluorescein isothiocyanate labeling and flow cytometry analysis. These MAPS were equally effective to scavenge hydroxyl and superoxide radicals in vitro and to attenuate the H2O2-, dextran sodium sulfate-, tumor necrosis factor α-, and interleukin 1ß-induced burst of intracellular reactive oxygen species and mitochondrial superoxide radicals, interleukin-8 production, cyclooxygenase-2 and inducible nitric oxide synthase expression, and/or tight junction disruption in polarized Caco-2 cells. MAPS and a positive drug Mesalazine were intragastrically administered to C57BL/6 mice daily for 7 d during and after 4-d dextran sodium sulfate exposure. Clinical signs and colon histopathology revealed equivalent anti-colitis efficacies of MAPS and Mesalazine, and based on biochemical analysis of colonic tight junction proteins, goblet cells, mucin 2 and trefoil factor 3 transcription, and colonic and peripheral pro-inflammatory cytokines, MAPS alleviated dextran sodium sulfate-induced intestinal epithelial barrier dysfunction, and their activities were even superior than Mesalazine. Overall, MAPS confer direct antioxidant and anti-inflammatory protection to intestinal epithelial barrier function.

The impact of the COVID-19 pandemic on SLE.

Little is known about the association between coronavirus disease 2019 (COVID-19) and autoimmune diseases, especially in the case of systemic lupus erythematosus (SLE). SLE patients met with many questions during the pandemic in COVID-19, such as how to minimize risk of infection, the complex pathological features and cytokine profiles, diagnosis and treatment, rational choice of drugs and vaccine, good nursing, psychological supervision, and so on. In this study, we review and discuss the multifaceted effects of the COVID-19 pandemic on patients living with SLE using the available literature. Cross-talk in implicated inflammatory pathways/mechanisms exists between SLE and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and SARS-CoV-2 displays similar clinical characteristics and immuno-inflammatory responses to SLE. Current epidemiological data inadequately assess the risk and severity of COVID-19 infection in patients with SLE. More evidence has shown that hydroxychloroquine and chloroquine cannot prevent COVID-19. During the pandemic, patients with SLE had a higher rate of hospitalization. Vaccination helps to reduce the risk of infection. Several therapies for patients with SLE infected with COVID-19 are discussed. The cases in the study can provide meaningful information for clinical diagnosis and management. Our main aim is to help preventing infection and highlight treatment options for patients with SLE infected with COVID-19.

Influence of the Essential Oil of Foeniculum vulgare Mill. on Sunflower Oil during the Deep-frying Process of Chinese Maye.

Sunflower oil (SFO) is faced with serious oxidation problems during the deep-frying of Chinese Maye, and the search for natural antioxidants has become a focus of scientific research due to the potential toxicity of synthetic antioxidants. In the present study, the Foeniculum vulgare Mill. essential oil (FVEO), tert-butylhydroquinone (TBHQ) were added to SFO for a 30 h deep frying experiment and the results showed that FVEO added to sunflower oil at 1 g/kg was similar to that of TBHQ-0.01 g/kg, and FVEO-1.5 g/kg would promote the oxidation of SFO. FVEO to sunflower oil also prominently restrained the decrease of the sensory properties of the fried product, Chinese Maye, including appearance, taste, flavor and overall acceptance by 24.2%, 20.2%, 46.1% and 56.0% (p < 0.01 or p < 0.05), respectively. The results indicated that FVEO could be used as a natural antioxidant to replace TBHQ in the deep-frying process of SFO, but further research is needed on the key antioxidant constituent of FVEO.

Factors affecting the simple febrile seizures in COVID-19 children: a case-control study from China.

Objective: The over-age phenomenon of simple febrile seizures (SFS) was found during the epidemic in COVID-19, but there was no clear explanation, especially in China. This study aimed to analyze the clinical and auxiliary examination features of SFS in children infected with the coronavirus disease 2019 (COVID-19). Methods: In total, 78 patients with SFS in the Department of Pediatric and Neurology of Qujing First People's Hospital were enrolled and divided into the COVID-19-positive group (case group) and the COVID-19-negative group (control group). The clinical characteristics, auxiliary examinations, and risk factors were analyzed. Results: There were significant differences in age stratification between the two groups. The proportion of children aged over 5 years old in the case group (47.4%) was higher than that of the control group (5%) (p < 0.0001). In terms of sex distribution, the proportion of males in the case group was higher than that in the control group (71.1% vs. 50%), but the difference was not statistically significant (p = 0.0678). For blood cell analysis, the values of white blood cells (WBC), lymphocytes (LY), and monocytes (MN) in the case group were significantly lower than those in the control group (p < 0.01). Serum electrolyte analysis showed the greatest difference in blood sodium. The proportion of hyponatremia in the case group was higher than that in the control group (36.8% vs. 17.5%), but the difference did not reach statistical significance (p = 0.0745). A multivariate logistic regression analysis showed that the history of FS was a independent protective factors for SFS in children with COVID-19 (OR = 0.115, p = 0.009), and age was an independent risk factor for SFS in children with COVID-19 (OR = 1.042, p = 0.001). Conclusion: Age distribution, sex a previous history of FS and hyponatremia were different between children with and without COVID-19 in SFS. The history of FS was an independent protective factors for SFS in children with COVID-19.

Safety assessment of Synechococcus sp. PCC 7002 biomass: genotoxicity, acute and subchronic toxicity studies.

Synechococcus sp. PCC 7002 has the potential to be used as a new resource of food owing to its nutritional and functional benefits. However, little information has been published regarding the safety of Synechococcus sp. PCC 7002 biomass (SynB). The present study assessed genotoxicity, acute and subchronic toxicity of SynB for the first time. SynB did not show any genotoxicity based on the Ames test, mammalian erythrocyte micronucleus test, and mouse primary spermatocyte chromosome aberration test. SynB administered by gavage in mice at a dose of 10 g per kg body weight did not induce death or toxicity based on the acute toxicity study, indicating the median lethal dose value of SynB was over 10 g per kg body weight. In the 90-day subchronic toxicity study, no treatment-related mortality or clinical sign was noted with SynB at doses of 5 and 10 g per kg body weight in mice, and there was no adverse effect of SynB on food consumption, organ coefficients, blood biochemistry, urinalysis and histopathology. The Non Observed Adverse Effect Level for SynB in female and male mice was not less than 10 g per kg body weight per day based on subchronic toxicity. These results support the safe use of SynB as a new food raw material.

Enhancement of Oxidative Stability of Deep-Fried Sunflower Oil by Addition of Essential Oil of Amomum villosum Lour.

In this study, the essential oil of the fruits of Amomum villosum Lour. (AVEO) was extracted through steam distillation and the components of the AVEO were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). Additionally, the antioxidant capacity in vitro of the AVEO was gauged using radical scavenging activity (DPPH, ABTS, superoxide anion) and ferric ion reducing antioxidant power (FRAP) assays; the antioxidant effect of a certain concentration of AVEO is even comparable to 0.08 mg/mL of butylated hydroxytoluene (BHT). Moreover, AVEO was applied to sunflower oil in a 30 h successive deep-frying experiment. Throughout the frying procedure, the sunflower oil-added antioxidant showed different degrees of benign changes in the physical and chemical parameters compared to the blank group, with 1 g/kg of AVEO being more consistent with 0.01 g/kg of tert-butyl hydroquinone (TBHQ), while 1.5 g/kg of essential oil revealed a stronger antioxidative capability. Meanwhile, the organoleptic characteristics of Chinese Maye, including its appearance, taste, flavor, and overall acceptability, were ameliorated when AVEO was added at 1.5 g/kg. Consequently, AVEO can be applied to substitute synthetic antioxidants as a natural antioxidant and flavoring agent during the deep-frying course of food.

Gum Arabic-Stabilized Ferric Oxyhydroxide Nanoparticles for Efficient and Targeted Intestinal Delivery of Bioavailable Iron.

Nanostructured iron(III) compounds are promising food fortificants with desirable iron bioavailability and food compatibility. Here, gum arabic (GA) solubilized 252 mg of iron(III) per g at neutral pH in the form of GA-stabilized ferric oxyhydroxide nanoparticles (GA-FeONPs) with Z-average size of 142.7 ± 5.9 nm and ζ-potential of -20.50 ± 1.25 mV. Calcein-fluorescence-quenching assay revealed well-absorbed iron from GA-FeONPs by polarized Caco-2 cells due to efficient macropinocytic internalization and asialoglycoprotein receptor-mediated specific endocytosis facilitated by the polypeptide and arabinogalactan fractions of GA, respectively, with endocytosed GA-FeONPs being in part basolaterally transcytosed and in another part degraded into cellular labile iron pool. GA-FeONPs showed good colloidal stability under varied pH, gastrointestinal, thermal processing, and spray/freeze drying conditions and displayed remarkably weaker pro-oxidant activity than FeSO4 in glyceryl trilinoleate emulsion (P < 0.05). Oral pharmacokinetics unveiled desirable iron bioavailability of GA-FeONPs relative to FeSO4, i.e., 124.27 ± 5.91% in aqueous solution and 161.64 ± 5.01% in milk. Overall, GA-FeONPs are a promising novel iron fortificant with food-compatible, efficient, and targeted intestinal iron delivery and sustained iron-release properties.

Imaging characteristics and treatment strategies of traumatic diaphragmatic hernia with aortic dissection: a report of 3 cases.

BACKGROUND: Traumatic aortic dissection with traumatic diaphragmatic hernia is a rare traumatic disease. The purpose of this article is to investigate the imaging characteristics and treatment strategies for traumatic diaphragmatic hernia with aortic dissection. CASE PRESENTATION: The imaging and clinical data of 3 patients with traumatic diaphragmatic hernia combined with aortic dissection were analyzed retrospectively. Of the three cases, two were males, and one was female; their mean age was 52.7 years (range, 47-62 years). Plain chest CT scans revealed diaphragmatic hernia in 2 patients, but no traumatic aortic dissection was found. Diaphragmatic hernia repair was performed in all patients. Aortic dilatation was found during intraoperative exploration, and aortic dissection was confirmed by postoperative enhanced CT. One patient underwent stent implantation and recovered smoothly (Case 1). The other patient refused stent implantation and died of thoracic hemorrhage (Case 2). The third patient underwent preoperative enhanced CT to identify traumatic diaphragmatic hernia with aortic dissection (Case 3). Aortic covered stent implantation was performed immediately, and diaphragmatic hernia repair was performed at a selected time. The patient's postoperative recovery was good. CONCLUSION: A preoperative plain chest CT scan indicated diaphragmatic hernia in major blunt thoracic trauma patients with a history of trauma and blurred periaortic spaces accompanied by hematocele and other imaging manifestations. Chest-enhanced CT should be performed to improve the diagnostic accuracy of aortic dissection.

Effects of Extreme Weather Events on Nitrous Oxide Emissions from Rice-Wheat Rotation Croplands.

Cropland ecosystems are significant emission sources of N2O, but a limited number of studies have focused on the impact of extreme weather events on N2O fluxes from cropland. This present study integrated field observations and model simulations to explore the responses of N2O fluxes to extreme weather events in typical rice and wheat rotation croplands in the middle and lower reaches of the Yangtze River (MLRYR) in China. The findings revealed that the studied rice-wheat rotation cropland exhibited a net source of N2O over the three-year monitoring period, with annual cumulative N2O emissions ranging from 190.4 to 261.8 mg N m-2. N2O emissions during the rice and wheat growing seasons accounted for 29% and 71% of the total yearly emissions, respectively. Extreme heat events led to a 23% to 32% increase in observed N2O emissions from cropland. Observed N2O emissions from irrigated rice fields during extreme precipitation events were 45% lower than those during extreme drought events. In contrast, extreme precipitation events raised observed N2O emissions from rain-fed wheat fields by 36% compared to the multi-year average, while extreme drought events reduced N2O emissions from wheat fields by 20%. Regional simulations indicated that annual cumulative N2O emissions from croplands in the MLRYR are projected to increase from 207.8 mg N m-2 under current climate to 303.4 mg N m-2 in the future. Given the episodic nature and uncertainties associated with N2O emissions from cropland, further validation is necessary for utilizing the model to explore the effects of extreme weather events on N2O in cropland ecosystems.

Collagen Peptides as a Hypoxia-Inducible Factor-2α-Stabilizing Prolyl Hydroxylase Inhibitor to Stimulate Intestinal Iron Absorption by Upregulating Iron Transport Proteins.

Iron intervention is not always safe and effective to correct iron deficiency. Host iron absorption stimulation is emerging as a promising adjunctive/alternative treatment. Here, porcine collagen hydrolysate (CH) and collagen-derived dipeptide prolyl-hydroxyproline, rather than collagen amino acids, namely, glycine, proline, and hydroxyproline, were found to increase cellular iron reduction, absorption, and transportation, to upregulate duodenal cytochrome b (Dcytb), divalent metal transporter 1 (DMT1), ferroportin (FPN), and hephaestin, and to nongenomically activate hypoxia-inducible factor-2α signaling in polarized Caco-2 cells. Prolyl-hydroxyproline showed both competitive and uncompetitive inhibition of recombinant human prolyl hydroxylase-3 activity with EC50 and Ki values of 10.62 and 6.73 µM, respectively. Docking simulations revealed collagen peptides as iron chelators and/or steric hindrances for prolyl hydroxylase-3. CH and prolyl-hydroxyproline acutely increased duodenal hypoxia-inducible factor-2α stability and Dcytb, DMT1, FPN, and hephaestin transcription in rats. Overall, collagen peptides act as a hypoxia-inducible factor-2α-stabilizing prolyl hydroxylase inhibitor to stimulate intestinal iron absorption.

Three-Dimensional Printing Properties of Polysaccharide Hydrocolloids-Unrinsed Sturgeon Surimi Complex Hydrogels.

Herein, the microstructure and mechanical properties of hydrogels consisting of unrinsed sturgeon surimi (URSS) and plant-derived polysaccharides such as κ-carrageenan (KC), konjac gum (KG), xanthan gum (XG), guar gum (GG) and sodium alginate (SA), were studied by texture analysis, rheological measurement and scanning electron microscopy (SEM). Rheological results showed that the apparent viscosity, storage modulus (G') and loss modulus (G″) of URSS increased by addition of KC, KG, GG and SA. The gel strength of resultant surimi products fabricated with KG/URSS mixture was significantly higher than that of other groups. KG could significantly improve the hardness (44.14 ± 1.14 N), chewiness (160.34 ± 8.33 mJ) and cohesiveness (0.56 ± 0.02) of the unrinsed surimi gel. Adding SA and KC had no significant effect on the textural characteristics of printed gels. However, an apparent decrease in the relevant mechanical properties of printed hydrogels was observed when XG and GG were added into surimi. SEM indicated that the incorporation of KG and KC could further integrate the gel structure of URSS as compared to hindering the cross-linking of surimi protein by XG and GG, which were in accordance with gel strength and water-holding capacity. These results provided useful information to regulate the 3D printing performance in functionalized surimi-based material.

High-throughput screening of 756 chemical contaminants in aquaculture products using liquid chromatography/quadrupole time-of-flight mass spectrometry.

A high-throughput screening method embracing 756 multiclass chemical contaminants in aquaculture products was developed using modified QuEChERS extraction coupled with liquid chromatography/quadrupole time-of-flight mass spectrometry. A mega-database with retention time/accurate mass data for 524 pesticides, 182 veterinary drugs, 32 persistent organic pollutants and 18 marine toxins was established for compound identification via retrospective library searching. In the four representative matrices (muscle tissues of tilapia and grouper, and edible portions of oyster and scallop), all the database compounds showed acceptable recovery and repeatability with the screening detection limit and limit of quantification below 0.01 mg/kg for >90% of them. The matrix-matched calibration revealed acceptable quantitative property of the method in terms of linear range, linearity, and matrix effect, and fish muscle samples showed stronger matrix effect than shellfish samples. Analysis of 64 real-life samples from aquaculture farms and retail markets evidenced applicability of the proposed method to high-throughput screening scenarios.