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Journal of the Science of Food and... Jun 2024To maintain the quality of frozen Atlantic salmon after thawing and highlight the potential for moving from air fright to boat for long-distance export, a study was...
BACKGROUND
To maintain the quality of frozen Atlantic salmon after thawing and highlight the potential for moving from air fright to boat for long-distance export, a study was designed to investigate the effects of sub-chilling before rapid freezing on the quality of thawed fillets. Atlantic salmon chilled on wet ice before filleting and freezing was used as a control for the experimental factor chilling, whereas fresh fillets were used for the frozen-thawed samples.
RESULTS
The pre-freezing chilling method interacted with the storage protocol and significantly affected the product. For fresh stored fillets, sub-chilling improved the microbiological and textural stability and degradation of proteins. After 1 month of frozen storage, sub-chilled fillets gave better color and textural properties, less adenosine triphosphate degradation and protein denaturation. In addition, sub-chilled 4-month-frozen fillets also showed improved microbial stability compared to those initially chilled with ice before frozen storage. Quality was lost as a function of storage. Fresh fillets generally had higher bacterial counts, surface breaking force, firmness, hue and contents of inosine monophosphate, and lower drip loss and inosine (HxR) levels than those stored frozen-thawed. Moreover, 4-month-frozen fillets had higher HxR levels and lower psychrotrophic viable count growth than those that were frozen for 1 month. The time fillets were stored frozen did not profoundly affect their quality.
CONCLUSION
It is concluded that a frozen product might be competitive with a fresh product when sub-chilling is performed before freezing, especially when including the environmental benefits of frozen export by boat rather than air freight. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
PubMed: 38843490
DOI: 10.1002/jsfa.13643 -
ACS Applied Materials & Interfaces Jun 2024The importance of amyloid nanofibrils made from food proteins is rising in diverse fields, such as biomedicine and food science. These protein nanofibrils (PNFs) serve...
The importance of amyloid nanofibrils made from food proteins is rising in diverse fields, such as biomedicine and food science. These protein nanofibrils (PNFs) serve as versatile and sustainable building blocks for biomaterials, characterized by their high β-sheet content and an ordered hydrogen bond network. These properties offer both stability and flexibility, along with an extreme aspect ratio and reactive functional groups. Plant-derived amyloid nanofibrils, such as soy protein isolate (SPI) PNFs, are increasingly favored due to their affordability and sustainability compared with animal proteins. This study aimed to explore the formation and application of SPI amyloid-like aggregates (SPIA) and their nanoencapsulation of curcumin (Cur) for biomedical purposes, particularly in wound healing. Under specific conditions of low pH and high temperature, SPIA formed, exhibited an amyloid nature, and successfully encapsulated Cur, thereby enhancing its stability and availability. Spectroscopic and microscopic analyses confirmed structural changes in SPIA upon the incorporation of Cur and the fabrication of SPIA@Cur. The obtained results indicate that in the presence of Cur, SPIA forms faster, attributed to accelerated SPI denaturation, an increased nucleation rate, and enhanced self-assembly facilitated by Cur's hydrophobic interactions and π-π stacking with SPI peptides. In vitro studies demonstrated the biocompatibility, biodegradability, and antioxidant properties of SPIA@Cur along with controlled release behavior. In vivo experiments in male Wistar rats revealed that both SPIA and SPIA@Cur significantly accelerate wound closure compared with untreated wounds, with SPIA@Cur showing slightly better efficacy. The histological analysis supported enhanced wound healing, indicating the potential of SPIA@Cur for biomedical applications.
Topics: Curcumin; Wound Healing; Soybean Proteins; Animals; Amyloid; Rats; Humans; Antioxidants; Nanofibers
PubMed: 38838270
DOI: 10.1021/acsami.4c06972 -
ACS Sensors Jun 2024Hepatic fibrosis, the insidious progression of chronic liver scarring leading to life-threatening cirrhosis and hepatocellular carcinoma, necessitates the urgent...
Hepatic fibrosis, the insidious progression of chronic liver scarring leading to life-threatening cirrhosis and hepatocellular carcinoma, necessitates the urgent development of noninvasive and precise diagnostic methodologies. Denatured collagen emerges as a critical biomarker in the pathogenesis of hepatic fibrosis. Herein, we have for the first time developed 3D-printed collagen capture chips for highly specific surface-enhanced Raman scattering (SERS) detection of denatured type I and type IV collagen in blood, facilitating the early diagnosis of hepatic fibrosis. Employing a novel blend of denatured collagen-targeting peptide-modified silver nanoparticle probes (Ag@DCTP) and polyethylene glycol diacrylate (PEGDA), we engineered a robust ink for the 3D fabrication of these collagen capture chips. The chips are further equipped with specialized SERS peptide probes, Ag@ICTP@R1 (S-I) and Ag@IVCTP@R2 (S-IV), tailored for the targeted detection of type I and IV collagen, respectively. The SERS chip platform demonstrated exceptional specificity and sensitivity in capturing and detecting denatured type I and IV collagen, achieving detection limits of 3.5 ng/mL for type I and 3.2 ng/mL for type IV collagen within a 10-400 ng/mL range. When tested on serum samples from hepatic fibrosis mouse models across a spectrum of fibrosis stages (S0-S4), the chips consistently measured denatured type I collagen and detected a progressive increase in type IV collagen concentration, which correlated with the severity of fibrosis. This novel strategy establishes a benchmark for the multiplexed detection of collagen biomarkers, enhancing our capacity to assess the stages of hepatic fibrosis.
Topics: Liver Cirrhosis; Spectrum Analysis, Raman; Collagen Type I; Animals; Printing, Three-Dimensional; Mice; Collagen Type IV; Silver; Metal Nanoparticles; Protein Denaturation; Humans; Polyethylene Glycols
PubMed: 38836565
DOI: 10.1021/acssensors.4c00623 -
RSC Advances May 2024An operationally simple one-pot three-component and convenient synthesis method for a series of diverse purine analogues of...
An operationally simple one-pot three-component and convenient synthesis method for a series of diverse purine analogues of 5-amino-7-(substituted)--(4-sulfamoylphenyl)-4,7-dihydro-[1,2,4]-triazolo[1,5-][1,3,5]triazine-2-carboxamide derivatives generated the reaction of 2-hydrazinyl--(4-sulfamoylphenyl)-2-thioxoacetamide, cyanoguanidine and a variety of aldehydes was achieved under green conditions. This experiment was conducted to evaluate the anti-inflammatory effect of the newly synthesized compounds using indomethacin as a reference medication; all compounds were tested for anti-inflammatory activity using the inhibition of albumin denaturation, RBC hemolysis technique and COX inhibition assay. The results showed that all evaluated compounds exhibited significant anti-inflammatory efficacy leading to excellently effective RBC membrane stabilization, inhibition of protein denaturation, and inhibition of COX enzymes when compared to those of indomethacin. At concentrations of 50, 100, 200, and 300 μg ml, these compounds decreased COX-1 and COX-2 activities more than indomethacin and have IC values in the range of 40.04-87.29 μg ml for COX-1 and 27.76-42.3 μg ml for COX-2 while indomethacin showed IC = 91.57 for COX-1 and 42.66 μg ml for COX-2. The anti-inflammatory findings show the need for more investigation to define the properties underlying the evaluated compounds' anti-inflammatory abilities. The enzyme cyclooxygenase-2 (COX 2) (PDB ID: 5IKT) was docked with ten synthetic substances. With docking scores () of -8.82, -7.82, and -7.76 kcal mol, 7-furan triazolo-triazine (4), 7-(2-hydroxy phenyl) triazolo-triazine (11), and 7-(4-dimethylamino phenyl) triazolo-triazine (12) had the greatest binding affinities, respectively. Therefore, these substances have COX-2 (PDB ID: 5IKT) inhibitory capabilities and hence may be investigated for COX 2 targeting development. Furthermore, both the top-ranked compounds (4 and 11) and the standard indomethacin were subjected to DFT analysis. The HOMO - LUMO energy difference (Δ) of the mentioned compounds was found to be less than that of indomethacin.
PubMed: 38832248
DOI: 10.1039/d4ra02970d -
Frontiers in Pharmacology 2024Cancer targeted therapy is essential to minimize damage to normal cells and improve treatment outcomes. The elevated activity of Cystathionine beta-synthase (CBS), an...
Benserazide, a cystathionine beta-synthase (CBS) inhibitor, potentially enhances the anticancer effects of paclitaxel via inhibiting the S-sulfhydration of SIRT1 and the HIF1-α/VEGF pathway.
Cancer targeted therapy is essential to minimize damage to normal cells and improve treatment outcomes. The elevated activity of Cystathionine beta-synthase (CBS), an enzyme responsible for producing endogenous hydrogen sulfide (HS), plays a significant role in promoting tumor growth, invasiveness, and metastatic potential. Consequently, the selective inhibition of CBS could represent a promising therapeutic strategy for cancer. Currently, there is much interest in combining paclitaxel with other drugs for cancer treatment. This study aimed to investigate the efficacy of combining benserazide, a CBS inhibitor, with paclitaxel in treating tumors. Firstly, we demonstrated CBS is indeed involved in the progression of multiple cancers. Then it was observed that the total binding free energy between the protein and the small molecule is -98.241 kJ/mol. The release of HS in the group treated with 100 μM benserazide was reduced by approximately 90% compared to the negative control, and the thermal denaturation curve of the complex protein shifted to the right, suggesting that benserazide binds to and blocks the CBS protein. Next, it was found that compared to paclitaxel monotherapy, the combination of benserazide with paclitaxel demonstrated stronger antitumor activity in KYSE450, A549, and HCT8 cells, accompanied by reduced cell viability, cell migration and invasion, as well as diminished angiogenic and lymphangiogenic capabilities. studies showed that the combined administration of benserazide and paclitaxel significantly reduced the volume and weight of axillary lymph nodes in comparison to the control group and single administration group. Further mechanistic studies revealed that the combination of benserazide and paclitaxel significantly suppressed the S-sulfhydration of SIRT1 protein, thereby inhibiting the expression of SIRT1 protein and activating SIRT1 downstream Notch1/Hes1 signaling pathway in KYSE450, A549, and HCT8 cells. Meanwhile, we observed that benserazide combined with paclitaxel induced a more significant downregulation of HIF-1α, VEGF-A, VEGF-C, and VEGF-D proteins expression levels in KYSE450, A549, and HCT8 cells compared to paclitaxel alone. These findings indicated that benserazide enhances the anticancer effects of paclitaxel via inhibiting the S-sulfhydration of SIRT1 and down-regulating HIF-1α/VEGF signaling pathway. This study suggests that benserazide may have potential as a chemosensitizer in cancer treatment.
PubMed: 38828455
DOI: 10.3389/fphar.2024.1404532 -
International Journal of Biological... Jun 2024The changes of physicochemical, structural and functional properties and the lysinoalanine (LAL) formation during the unfolding and refolding of black soldier fly larvae...
Changes in physicochemical, structural and functional properties, and lysinoalanine formation during the unfolding and refolding of pH-shifted black soldier fly larvae albumin.
The changes of physicochemical, structural and functional properties and the lysinoalanine (LAL) formation during the unfolding and refolding of black soldier fly larvae albumin (BSFLA) induced by acid/alkaline pH shift were explored. The results showed that acid/alkaline conditions induced unfolding of BSFLA structure, but also accompanied by the formation of some large aggregates due to the hydrophobic interactions, hydrogen bonds, and disulfide bonds. Compared with control or pH shift, pH shift treatment significantly increased the electrostatic repulsion, surface hydrophobicity, free sulfhydryl group, and deamidation reactions, but reduced the fluorescence intensity of BSFLA, and these change in protein conformation contributed to increase in solubility, emulsion activity, and emulsion stability. But the content of LAL in BSFLA was increased by 93.39 % by pH shift treatment. In addition, pH shift modified BSFLA tended to form β-sheet structure through unfolding and refolding, resulting in the formation of aggregates with larger particle sizes, and reducing the solubility and the LAL content by 7.93 % and 65.53 %, respectively. SDS-PAGE profile showed that pH shifting did not cause irreversible denaturation of protein molecules. Therefore, pH-shift is good way to improve the functional properties of BSFLA, but the content of LAL should be reduced to make it better used in food.
Topics: Animals; Hydrogen-Ion Concentration; Protein Unfolding; Lysinoalanine; Hydrophobic and Hydrophilic Interactions; Larva; Albumins; Diptera; Solubility; Protein Refolding; Insect Proteins; Chemical Phenomena
PubMed: 38825263
DOI: 10.1016/j.ijbiomac.2024.132801 -
Biochemical and Biophysical Research... Sep 2024Rab3A is a member of the Rab GTPase family involved in synaptic vesicle trafficking. Recent evidence has demonstrated that Rab3A is phosphorylated by leucine-rich repeat...
Rab3A is a member of the Rab GTPase family involved in synaptic vesicle trafficking. Recent evidence has demonstrated that Rab3A is phosphorylated by leucine-rich repeat kinase 2 (LRRK2) that is implicated in both familial and sporadic forms of Parkinson's disease (PD), and an abnormal increase in Rab3A phosphorylation has been proposed as a cause of PD. Despite the potential importance of Rab3A in PD pathogenesis, its structural information is limited and the effects of bound nucleotides on its biophysical and biochemical properties remain unclear. Here, we show that GDP-bound Rab3A is preferentially phosphorylated by LRRK2 compared with GTP-bound Rab3A. The secondary structure of Rab3A, measured by circular dichroism (CD) spectroscopy, revealed that Rab3A is resistant to heat-induced denaturation at pH 7.4 or 9.0 regardless of the nucleotides bound. In contrast, Rab3A underwent heat-induced denaturation at pH 5.0 at a lower temperature in its GDP-bound form than in its GTP-bound form. The unfolding temperature of Rab3A was studied by differential scanning fluorimetry, which showed a significantly higher unfolding temperature in GTP-bound Rab3A than in GDP-bound Rab3A, with the highest at pH 7.4. These results suggest that Rab3A has unusual thermal stability under physiologically relevant conditions and that bound nucleotides influence both thermal stability and phosphorylation by LRRK2.
Topics: Phosphorylation; Guanosine Triphosphate; Humans; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Protein Structure, Secondary; rab3A GTP-Binding Protein; Guanosine Diphosphate; Protein Stability
PubMed: 38824807
DOI: 10.1016/j.bbrc.2024.150199 -
Food Research International (Ottawa,... Jul 2024Myofibrillar proteins are crucial for gel formation in processed meat products such as sausages and meat patties. Freeze-thaw cycles can alter protein properties,...
Myofibrillar proteins are crucial for gel formation in processed meat products such as sausages and meat patties. Freeze-thaw cycles can alter protein properties, impacting gel stability and product quality. This study aims to investigate the potential of thawed drip and its membrane-separated components as potential antifreeze agents to retard denaturation, oxidation and gel deterioration of myofibrillar proteins during freezing-thawing cycles of pork patties. The thawed drip and its membrane-separated components of > 10 kDa and < 10 kDa, along with deionized water, were added to minced pork at 10 % mass fraction and subjected to increasing freeze-thaw cycles. Results showed that the addition of thawed drip and its membrane separation components inhibited denaturation and structural changes of myofibrillar proteins, evidenced by reduced surface hydrophobicity and carbonyl content, increased free sulfhydryl groups, protein solubility and α-helix, as compared to the deionized water group. Correspondingly, improved gel properties including water-holding capacity, textural parameters and denser network structure were observed with the addition of thawed drip and its membrane separation components. Denaturation and oxidation of myofibrillar proteins were positively correlated with gel deterioration during freezing-thawing cycles. We here propose a role of thawed drip and its membrane separation components as cryoprotectants against myofibrillar protein gel deterioration during freeze-thawing cycles.
Topics: Freezing; Animals; Gels; Swine; Muscle Proteins; Myofibrils; Food Handling; Protein Denaturation; Meat Products; Hydrophobic and Hydrophilic Interactions; Solubility; Water; Oxidation-Reduction
PubMed: 38823861
DOI: 10.1016/j.foodres.2024.114461 -
Environmental Research May 2024The study aimed to analyze the pharmacological properties of medicinal plant Indigofera hochstetteri Baker extracts. Preliminary phytochemical analysis revealed a...
Comprehensive in vitro evaluation of Indigofera hochstetteri Baker extract: Effect of chemicals in antimicrobial, anticancer, anti-inflammatory, and anti-diabetic activities.
The study aimed to analyze the pharmacological properties of medicinal plant Indigofera hochstetteri Baker extracts. Preliminary phytochemical analysis revealed a diverse range of secondary metabolites present in it. TLC analysis detected numerous phytochemicals with varying Rf values, aiding in different solvent systems. GC-MS analysis revealed the presence of 29 bioactive compounds with diverse pharmacological activities, including anti-inflammatory, antioxidant, analgesic and antimicrobial properties. Antimicrobial effect of I. hochstetteri Baker methanolic extract showed significant inhibitory effects against E. coli, E. aerogenes, S. flexneri, P. aeruginosa, S. aureus, E. faecalis, B. cereus, and fungal strain C. albicans. The methanol extract also showed significant antifungal activity by inhibiting the growth of Sclerotium rolfsii in food poisoning method. MTT assays revealed significant cytotoxic activity of methanolic extract against human leukemia HL-60 cancer cells with IC of 116.01 μg/mL. In apoptotic study, I. hochstetteri Baker methanolic extract showed 28.84% viable cells, 30.2% early apoptosis, 35.54% late apoptosis, and 5.86% necrosis comparatively similar with standard used. The extract showed significant anti-inflammatory effect on HRBC stabilization, and protein denaturation of BSA and egg albumin denaturation with IC of 193.62 μg/mL, 113.94 μg/mL respectively. In anti-diabetic assays like α-amylase, α-glucosidase, and Glucose uptake assay, I. hochstetteri extract showed good anti-diabetic effect with IC of 60.64 μg/mL, 169.34 μg/mL, and 205.63 μg/mL respectively. In conclusion I. hochstetteri Baker have promising bioactive metabolites with significant biological activities, it can be good substitute for the chemical drugs after successful clinical studies.
PubMed: 38823619
DOI: 10.1016/j.envres.2024.119288 -
Acta Neuropathologica Communications May 2024Alpha-synuclein (αsyn) is an intrinsically disordered protein that aggregates in the brain in several neurodegenerative diseases collectively called synucleinopathies....
Alpha-synuclein (αsyn) is an intrinsically disordered protein that aggregates in the brain in several neurodegenerative diseases collectively called synucleinopathies. Phosphorylation of αsyn at serine 129 (PSER129) was considered rare in the healthy human brain but is enriched in pathological αsyn aggregates and is used as a specific marker for disease inclusions. However, recent observations challenge this assumption by demonstrating that PSER129 results from neuronal activity and can be readily detected in the non-diseased mammalian brain. Here, we investigated experimental conditions under which two distinct PSER129 pools, namely endogenous-PSER129 and aggregated-PSER129, could be detected and differentiated in the mammalian brain. Results showed that in the wild-type (WT) mouse brain, perfusion fixation conditions greatly influenced the detection of endogenous-PSER129, with endogenous-PSER129 being nearly undetectable after delayed perfusion fixation (30-min and 1-h postmortem interval). Exposure to anesthetics (e.g., Ketamine or xylazine) before perfusion did not significantly influence endogenous-PSER129 detection or levels. In situ, non-specific phosphatase calf alkaline phosphatase (CIAP) selectively dephosphorylated endogenous-PSER129 while αsyn preformed fibril (PFF)-seeded aggregates and genuine disease aggregates (Lewy pathology and Papp-Lantos bodies in Parkinson's disease and multiple systems atrophy brain, respectively) were resistant to CIAP-mediated dephosphorylation. The phosphatase resistance of aggregates was abolished by sample denaturation, and CIAP-resistant PSER129 was closely associated with proteinase K (PK)-resistant αsyn (i.e., a marker of aggregation). CIAP pretreatment allowed for highly specific detection of seeded αsyn aggregates in a mouse model that accumulates non-aggregated-PSER129. We conclude that αsyn aggregates are impervious to phosphatases, and CIAP pretreatment increases detection specificity for aggregated-PSER129, particularly in well-preserved biological samples (e.g., perfusion fixed or flash-frozen mammalian tissues) where there is a high probability of interference from endogenous-PSER129. Our findings have important implications for the mechanism of PSER129-accumulation in the synucleinopathy brain and provide a simple experimental method to differentiate endogenous-from aggregated PSER129.
Topics: Animals; Humans; Male; Mice; Alkaline Phosphatase; alpha-Synuclein; Brain; Mice, Inbred C57BL; Mice, Transgenic; Phosphoric Monoester Hydrolases; Phosphorylation; Protein Aggregates; Protein Aggregation, Pathological; Synucleinopathies
PubMed: 38822421
DOI: 10.1186/s40478-024-01785-0