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Turmeric rhizomes (Curcuma longa) and black cumin seeds (Nigella sativa) are polyherbal ingredients used for the management of cancer and other chronic inflammatory diseases in Nigerian ethnomedicine. Previous studies have shown the antioxidant, anti-inflammatory, and anticancer activities of the individual plant extracts. However, the two spices have not been biologically potentiated in their combined form. Therefore, this study obtained essential oils (EOs) from the combined spices and evaluated their inhibitory effects on free radicals, protein denaturation, and cancer proliferation. The EOs were extracted by hydro-distillation (HD) and characterized by gas chromatography-mass spectrometry (GC-MS). In vitro antioxidant assessment was conducted based on DPPH, hydrogen peroxide (H2O2), nitric oxide (NO), and ferric ion (Fe3+) radical scavenging assays. The cytotoxicity of the oil against non-tumorigenic (HEK293) and cancerous (HepG2 and HeLa) cell lines was determined following the MTT cell viability assay. An in silico molecular docking analysis of the oil constituents was also performed. Six batches of EOs I–VI were afforded, comprising twenty-two major constituents, with aromatic Ar-turmerone being the most prominent compound. There was a marked improvement in the bioactivity of the oils upon repeated HD and as a combination. The batch VI oil exhibited the best activity, with a cytotoxicity (CC50) of 10.16 ± 1.69 µg/100 µL against the HepG2 cell line, which was comparable to 5-fluorouracil (standard, CC50 = 8.59 ± 1.33 µg/100 µL). In silico molecular docking suggested δ-curcumene, Ar-curcumene, Ar-turmerol, and Ar-turmerone among the promising compounds based on their high binding energy scores with NOX2, NF-κB, and mdm2 proteins. In conclusion, the oils from the turmeric–black cumin combined possess a considerable inhibition ability against free radicals, protein denaturation, and cancer proliferation. This study's findings further underscore the effectiveness of turmeric–black cumin as a polyherbal medicinal ingredient. [ABSTRACT FROM AUTHOR]

This study investigated the effects of isochoric freezing (IF) on the shelf-life and quality of raw bovine milk over a 5-week period. The results were compared with conventional refrigeration (RF) and refrigeration after pasteurization (HTST). The IF treatment process entailed storing liquid raw milk in isochoric chambers in thermodynamic equilibrium at -5 °C/77 MPa and -10 °C/96 MPa. Several parameters were analyzed, including microbiology count, physicochemical properties, indigenous enzyme activity, protein content, volatile organic compounds profile, and lipid degradation. Both raw and pasteurized milk experienced increases in the microbial level past the acceptable threshold (≥5.5 log CFU/mL) after 2 weeks and 5 weeks, respectively, leading to the deterioration of other parameters during storage. In comparison, microbiology count decreased significantly during storage for both IF treatment conditions but was more pronounced for the higher pressure (96 MPa) treatment, leading to undetectable levels of microorganism after 5 weeks. IF treatment maintained stable pH, titratable acidity, viscosity, lipid oxidation, volatile profiles, total protein content, and lactoperoxidase activity throughout the storage period. Color was preserved during IF treatment at -5 °C/77 MPa; however, color was impacted during IF treatment at -10 °C/96 MPa. Protein structures were also modified during pressurized storage in both IF treatments. Overall, the study demonstrated that isochoric freezing could significantly increase the shelf-life of milk by reducing microbiology activity, whilst maintaining its nutritional content. These results underscore the potential role of isochoric freezing as a valuable tool in eliminating pathogens while maintaining quality characteristics similar to raw milk over long storage periods.

The purpose of this study was to reduce the loss of spent laying hens during slaughtering by adjusting the parameters of scalding. The research object of this study was the spent laying hens with a rearing age of more than 400 days. The research meant to explore the effect of scalding methods on feather removing and muscle overheating. Three scalding parameters were set as follow: 65 ℃-3 min (high temperature scalding, HS), 60 ℃-4 min 20 s (medium temperature and slow scalding, MSS), and 58 ℃-4 min 20 s (low temperature and slow scalding, LSS). Broilers without scalding were set as the control group. The defeathering effect was characterized by measuring the feather retention force (FRF) and counting the number of feathers remaining after defeathering. The overheating degree of breast muscle was characterized by measuring meat color, depth of overheating area, DSC scanning and Raman spectrum scanning. The results showed that no significant difference in feather removal effects between HS treatments and LSS treatments, while the feather retention force and residual feather number of MSS treatment were significantly lower than those of the other two groups (P

Alpinia monopleura is one of the endemic plants of Sulawesi, and it has an extensive distribution in the region. Research on chemical compounds and biological activities of A. monopleura is essential to continue as an effort to support the utilization of native plants for medicine. The extract was obtained using the maceration method. The chemical compounds in the extract were identified using Liquid Chromatography Mass Spectrometry (LCMS). Bovine Serum Albumin (BSA) and molecular docking methods were used to evaluate the anti-inflammatory activity. Ten compounds contained in the extract were successfully identified, E-para-coumaric acid (1), trans-ferulaldehyde (2), 3,5,6-trihydroxy-4',7-dimethoxyflavone (3), nevadensin (4), malvalic acid (5), ent-16α,17-hydroxy-19-kauranoic acid (6), 3',5-dihydroxy-7,4'-dimethoxy flavone (7), saurufuran B (8), 5-hydroxy-7,8,2'-trimethoxyflavanone (9) and dehydroabietic acid (10). The anti-inflammatory activity of extracts from rhizomes and stems of A. monopleura were 8.62 and 10.59 mg/L, respectively. Some flavonoids (9 and 7) can bind strongly to specific residues around the COX-2 active site, such as Ser530, thereby interfering with the function of the COX-2 enzyme and reducing the production of pro-inflammatory prostaglandins. Thus, A. monopleura extract has the potential to inhibit inflammatory responses through molecular regulation of the COX-2 enzyme. [ABSTRACT FROM AUTHOR]

This study investigates the impact of dry heat pretreatment on the functionality of soy, chickpea, and pea protein ingredients for use in texturized vegetable protein (TVP) production via low moisture extrusion. The protein powders were heat-treated at temperatures ranging from 80 °C to 160 °C to modulate the extent of protein denaturation and assess their effects on RVA pasting behavior, water absorption capacity (WAC), and color attributes. The results indicate that the pretreatment temperature significantly influenced the proteins' functional properties, with an optimal temperature of 120 °C enhancing pasting properties and maintaining WAC, while a higher pretreatment temperature of 160 °C led to diminished ingredient functionality. Different protein sources exhibited distinct responses to heat pretreatment. The subsequent extrusion processing revealed significant changes in extrudate density and color, with increased density and darkness observed at higher pretreatment temperatures. This research provides insights into the interplay between protein sources, pretreatment conditions, and extrusion outcomes, highlighting the importance of controlled protein denaturation for developing high-quality, plant-based meat analogues. The findings have broad implications for the optimization of meat analogue manufacturing, with the aim of enhancing the sensory experience and sustainability of plant-based foods. [ABSTRACT FROM AUTHOR]

GdmCl and NaSCN are two strong chaotropic salts commonly used in protein folding and stability studies, but their microscopic mechanisms remain enigmatic. Here, by CD and NMR, we investigated their effects on conformations, stability, binding and backbone dynamics on ps-ns and µs-ms time scales of a 39-residue but well-folded WW4 domain at salt concentrations ≤200 mM. Up to 200 mM, both denaturants did not alter the tertiary packing of WW4, but GdmCl exerted more severe destabilization than NaSCN. Intriguingly, GdmCl had only weak binding to amide protons, while NaSCN showed extensive binding to both hydrophobic side chains and amide protons. Neither denaturant significantly affected the overall ps-ns backbone dynamics, but they distinctively altered µs-ms backbone dynamics. This study unveils that GdmCl and NaSCN destabilize a protein before the global unfolding occurs with differential binding properties and µs-ms backbone dynamics, implying the absence of a simple correlation between thermodynamic stability and backbone dynamics of WW4 at both ps-ns and µs-ms time scales. [ABSTRACT FROM AUTHOR]

This study explored the intrinsic relationship between the quality traits and protein-related property changes during the solar drying of shrimps (Penaeus vannamei). During drying, the shrimp exhibited a gradual decline in L*a*b* values and a notable increase in the hardness and chewiness. Proteins were degraded and oxidized. Especially, the trichloroacetic acid-soluble peptide and carbonyl contents increased, whereas the total sulfhydryl content decreased. The proportions of different types of intramolecular bonds were significantly changed. The ionic and hydrogen bonds greatly decreased to 10.72% and 9.05% and the hydrophobic and disulfide bonds notably increased to 19.38% and 28.19%, indicating the changes in the spatial structure of the protein and its denaturation during the drying process. The Pearson's correlation analysis showed that protein degradation and denaturation greatly affected the textural properties and protein oxidation caused color changes. The result of this work provides a theoretical support for improving the quality of shrimp products.

Drying, as a critical step in the production of air-dried beef, has a direct impact on the quality of the final product. Innovatively, a composite system incorporating contact ultrasound (CU) and infrared radiation (IR) as auxiliary measures within a hot air drying (HAD) framework was built in this research, and the effects of these techniques on the drying kinetics, protein denaturation, and moisture transformation of air-dried beef were investigated. In comparison to HAD treatment, the integrated CU and IR (CU-IRD) system displayed marked enhancements in heat and moisture transport efficiency, thereby saving 36.84% of time expenditure and contributing favorably to the improved moisture distribution of the end-product. This was mainly ascribed to the denaturation of myosin induced by IR thermal effect and the micro-channel produced by CU sponge effect, thus increasing T2 relaxation time and the proportion of free water. In conclusion, the composite system solved the problem of surface hardening and reduces hardness and chewiness of air-dried beef by 40.42% and 45.25% respectively, but inevitably increased the energy burden by 41.60%.

Preliminary assessment for anti-inflammatory and anti-lipidemic properties was done with different solvent extracts derived from Urtica urens and Polygonum chinense leaves through in vitro experimentation. To evaluate anti-inflammatory properties, the stability of human red blood cells membranes and the denaturation activity of proteins were assessed. For anti-lipidemic effects, an assay was conducted to measure the inhibition of HMG-CoA reductase. The results of membrane stabilization showed IC50 values of 480.96 ± 0.02 and 319.41 ± 0.19 µg/mL for ethyl acetate extract of U. urens and P. chinense, respectively. The standard drug Diclofenac sodium exhibited IC50 value of 240.37 ± 0.04 µg/mL. For protein denaturation, IC50 values were determined as 221.75 ± 0.2 and 315.76 ± 0.19 µg/mL for U. urens and P. chinense, respectively. The IC50 value of the standard drug was calculated as 126.7 ± 0.34. The IC50 values towards HMG-CoA reductase inhibition were subsequently determined as 29.84 ± 0.35 µg/mL for U. urens and 24.34 ± 0.04 µg/mL for P. chinense against the standard drug Diclofenac sodium (7.52 ± 0.43 µg/mL). GC-MS chromatograms revealed the presence of bioactive compounds in ethyl acetate extract of P. chinense leaves. This work is substantiation for the traditional therapeutic utilization of these extracts.

Inflammation is a physiological process that serves as a defense mechanism for the body against foreign substances, bacteria, or irritants. Inflammation can be cured with anti-inflammatory drugs. One of the plants that has the potential to be an anti-inflammatory agent is the bamboo leaf. This research aims to analyze the content of secondary metabolites, determine the inhibition value and IC50 value of the anti-inflammatory activity of the ethanol extract of bamboo tali leaves. Bamboo tali leaves were macerated using 96% ethanol and subjected to phytochemical screening. The extract was then tested for anti-inflammatory activity in vitro with the Bovine Serum Albumin (BSA) protein denaturation inhibition method. Bamboo tali leaf ethanol extract contains flavonoids, alkaloids, saponins, and phenols. The anti-inflammatory activity of the ethanol extract of bamboo tali leaves with concentrations of 28, 42, 56, 70, and 84 ppm had an inhibition percentage value of 23.14 ± 0.008%; 34.30 0.026%; 54.51 0.060%; 69.07 ± 0.006%; and 87.02 ± 0.021% with an IC50 value of 52.991 ppm. These results indicate that the ethanol extract of bamboo tali leaves has the potential to be an anti-inflammatory with a strong IC50 value below 100 ppm.

Preliminary assessment for anti-inflammatory and anti-lipidemic properties was done with different solvent extracts derived from Urtica urens and Polygonum chinense leaves through in vitro experimentation. To evaluate anti-inflammatory properties, the stability of human red blood cells membranes and the denaturation activity of proteins were assessed. For anti-lipidemic effects, an assay was conducted to measure the inhibition of HMG-CoA reductase. The results of membrane stabilization showed IC50 values of 480.96 ± 0.02 and 319.41 ± 0.19 µg/mL for ethyl acetate extract of U. urens and P. chinense, respectively. The standard drug Diclofenac sodium exhibited IC50 value of 240.37 ± 0.04 µg/mL. For protein denaturation, IC50 values were determined as 221.75 ± 0.2 and 315.76 ± 0.19 µg/mL for U. urens and P. chinense, respectively. The IC50 value of the standard drug was calculated as 126.7 ± 0.34. The IC50 values towards HMG-CoA reductase inhibition were subsequently determined as 29.84 ± 0.35 µg/mL for U. urens and 24.34 ± 0.04 µg/mL for P. chinense against the standard drug Diclofenac sodium (7.52 ± 0.43 µg/mL). GC-MS chromatograms revealed the presence of bioactive compounds in ethyl acetate extract of P. chinense leaves. This work is substantiation for the traditional therapeutic utilization of these extracts. [ABSTRACT FROM AUTHOR]

Chemical chaperones are low-molecular-weight compounds that suppress protein aggregation. They can influence different stages of the aggregation process—the stage of protein denaturation, the nucleation stage and the stage of aggregate growth—and this may lead to a change in the aggregation kinetic regime. Here, the possibility of changing the kinetic regime in the presence of a chemical chaperone 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) was investigated for a test system based on the thermally induced aggregation of yeast alcohol dehydrogenase (yADH) at 56 °C. According to differential scanning calorimetry data, 2-HP-β-CD did not affect the stage of the protein molecule unfolding. Dynamic light scattering data indicated changes in the aggregation kinetics of yADH during the nucleation and aggregate growth stages in the presence of the chaperone. The analysis of kinetic curves showed that the order of aggregation with respect to protein (nc), calculated for the stage of aggregate growth, changed from nc = 1 to nc = 2 with the addition of 100 mM 2-HP-β-CD. The mechanism of 2-HP-β-CD action on the yADH thermal aggregation leading to a change in its kinetic regime of aggregation is discussed. [ABSTRACT FROM AUTHOR]

Indirect immunofluorescence is usually restricted to 3-5 markers per preparation, limiting analysis of coexistence. A solution containing 2-mercaptoethanol and sodium dodecyl sulfate (2-ME/SDS) can elute indirect immunofluorescence labelling (i.e. primary antisera followed by fluorophore-conjugated secondary antisera) and has been used for sequential staining of sections. The aim of this study was to test whether 2-ME/SDS is effective for eluting indirect immunofluorescent staining (with primary antisera visualised by fluorophore-coupled secondary antisera) in wholemount preparations. We also analysed how 2-ME/SDS may work and used this understanding to devise additional uses for immunofluorescence in the nervous system. 2-ME/SDS appears to denature unfixed proteins (including antisera used as reagents) but has much less effect on antigenicity of formaldehyde-fixed epitopes. Moieties linked by strong biotin-streptavidin bonds are highly resistant to elution by 2-ME/SDS. Two primary antisera raised in the same species can be applied without spurious cross-reactivity, if a specific order of labelling is followed. The first primary antiserum is followed by a biotinylated secondary, then a tertiary of fluorophore-conjugated streptavidin. The preparation is then exposed to 2-ME/SDS, which has minimal impact on labelling by the first primary/secondary/tertiary combination. However, when this is followed by a second primary antiserum (raised in the same species), followed by a fluorophore-conjugated secondary antiserum, the intervening 2-ME/SDS exposure prevents cross-reactivity between primary and secondary antisera of the two layers. A third property of 2-ME/SDS is that it reduces lipofuscin autofluorescence, although it also raises background fluorescence and strongly enhances autofluorescence of erythrocytes. In summary, 2-ME/SDS is easy to use, cost-effective and does not require modified primary antisera. It can be used as the basis of a multi-layer immunohistochemistry protocol and allows 2 primary antisera raised in the same species to be used together.

Background: Capparis cartilaginea Decne.(C. cartilaginea Decne.) a medicinally important plant that belongs to the family Capparaceae. Traditionally the fruit, leaf, and root have been believed to show anti-inflammatory effects and can also be used as agents. Purpose: The objective of this study is to investigate the chemical compositions, in-vitro antioxidant, anti-cancer and anti-inflammatory activities of the ethanolic extract of Capparis cartilaginea Decne. leaves. Study methods: The chemical compounds were investigated by Gas Chromatography–Mass Spectrometry (GC–MS) analysis. Ferric-bipyridine reducing capacity of total antioxidants (FBRC), Ferric reducing antioxidant power (FRAP) were utilized to determine antioxidant activity. The cytotoxic activity was evaluated using a 3-[4,5-dimethylthiazole- 2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay. Additionally, in vitro anti-inflammatory activity of the ethanolic extract of C. cartilaginea Decne. leaves using COX1 and protein denaturation methods. Results: The major twenty- four bioactive compounds from fifty compounds were identified including alkaloids, flavonoids, phenols, fatty acids, and carotenes. Pleiocarpamine was the major constituent of the extract (73.07 %). Additionally, in vitro anti-inflammatory activity of the ethanolic extract of C. cartilaginea Decne. leaves using COX1 and protein denaturation methods showed a strong effect with IC50 values of 60.23 and 17.67 µg/mL respectively, compared to Indomethacin and Diclofenac as a standard anti-inflammatory drug.; while FBRC and FRAP were utilized to determine antioxidant activity slowed high antioxidants capacity with values 0.056 ± 0.001and 0.03 ± 0.00196 Ascorbic acid equivalent/g of extract (AAE) and DPPH radical scavenging method show IC50 value 10 ± 1 %. Evaluation of the cytotoxic activity against three human cancer cell lines colon carcinoma cells HCT-116, Breast carcinoma cells MCF-7, and human muscle Rhabdomyosarcoma RD cell line using MTT assay showed a significant effect with IC50 values 59.58 ± 1.5, 39.14 ± 3.09, and 102 ± 8.75 µg/mL, compared to Vinblastine Sulfate as a standard cytotoxic drug. Yemeni C. cartilaginea Decne. showed a higher effect on MCF-7 compared to Iranian C. cartilaginea Decne. as well as established a higher antioxidant activity than that extracts obtained from Jordan. Conclusion: Ethanolic leaves extract of C. cartilaginea Decne. have the potential for development as therapeutic agents for cytotoxicity on certain cancer cells following further investigation. C. cartilaginea Decne. leaves that could have medicinal values and application in industries, were used to design the drug for the treatment of various types of inflammatory diseases.

In order to investigate the intrinsic relationship between protein characteristics and quality changes during the hot air drying of shrimp, Penaeus vannamei was dried by hot air at 55 ℃ after being boiled in 3% salt solution for 2 minutes. We studied changes in the microstructure and quality of shrimp, and systematically investigated changes in the oxidative degradation degree, intramolecular valence bonds, and secondary and tertiary structure of protein. The results showed that the drying treatment gradually decreased the L*, a* and b* values of shrimp, and changed the texture characteristics, and the hardness, adhesiveness and chewiness were increased to 344.78 N, 45.01 mJ and 116.50 mJ at the end of drying, respectively. In addition, oxidative denaturation and degradation of proteins occurred; the total sulfhydryl content decreased to 0.36 μmol/g at the end of drying, while the carbonyl content increased to 2.03 nmol/mg protein, and the trichloroacetic acid (TCA)-soluble peptide content increased to 0.91 μmol/g. The protein structure was significantly changed; the relative contents of ionic and hydrogen bonds decreased, the relative contents of hydrophobic and disulfide bonds increased, the secondary structure was transformed from α-helix to β-fold, β-turn and random coil, the intensity of tryptophan fluorescence decreased, and the tertiary structure was also changed. Pearson correlation analysis showed that the color changes were mainly related to protein oxidation and protein degradation and denaturation significantly affected the textural properties of shrimp. This study can provide theoretical support for further improving the quality of dried shrimp products.

Defining the denatured state ensemble (DSE) and disordered proteins is essential to understanding folding, chaperone action, degradation, and translocation. As compared with water-soluble proteins, the DSE of membrane proteins is much less characterized. Here, we measure the DSE of the helical membrane protein GlpG of Escherichia coli (E. coli) in native-like lipid bilayers. The DSE was obtained using our steric trapping method, which couples denaturation of doubly biotinylated GlpG to binding of two streptavidin molecules. The helices and loops are probed using limited proteolysis and mass spectrometry, while the dimensions are determined using our paramagnetic biotin derivative and double electron-electron resonance spectroscopy. These data, along with our Upside simulations, identify the DSE as being highly dynamic, involving the topology changes and unfolding of some of the transmembrane (TM) helices. The DSE is expanded relative to the native state but only to 15 to 75% of the fully expanded condition. The degree of expansion depends on the local protein packing and the lipid composition. E. coli's lipid bilayer promotes the association of TM helices in the DSE and, probably in general, facilitates interhelical interactions. This tendency may be the outcome of a general lipophobic effect of proteins within the cell membranes.

The interactions of proteins with surfaces are important in both biological processes and biotechnologies. In contrast to decades of study regarding the biophysics of proteins in bulk solution, however, our mechanistic understanding of the biophysics of proteins interacting with surfaces remains largely qualitative. In response, we have set to explore quantitatively the thermodynamics of protein-surface interactions. In this work, we explore systematically the role of electrostatics in modulating the interaction between proteins and charged surfaces. In particular, we use electrochemistry to explore the extent to which a macroscopic, hydroxyl-coated surface held at a slightly negative potential affects the folding thermodynamics of surface-attached protein variants with different composition of charged amino acids. Doing so, we find that attachment to the surface generally leads to a net stabilization, presumably due to excluded volume effects that reduce the entropy of the unfolded state. The magnitude of this stabilization, however, is strongly correlated with the charged-residue content of the protein. In particular, we find statistically significant correlations with both the net charge of the protein, with greater negative charge leading to less stabilization by the surface, and with the number of arginines, with more arginines leading to greater stabilization. Such findings refine our understanding of protein-surface interactions, providing in turn a guiding rationale to achieve the functional deposition of proteins on artificial surfaces for implementation in, for example, protein-based biotechnologies.

Turmeric rhizomes (Curcuma longa) and black cumin seeds (Nigella sativa) are polyherbal ingredients used for the management of cancer and other chronic inflammatory diseases in Nigerian ethnomedicine. Previous studies have shown the antioxidant, anti-inflammatory, and anticancer activities of the individual plant extracts. However, the two spices have not been biologically potentiated in their combined form. Therefore, this study obtained essential oils (EOs) from the combined spices and evaluated their inhibitory effects on free radicals, protein denaturation, and cancer proliferation. The EOs were extracted by hydro-distillation (HD) and characterized by gas chromatography-mass spectrometry (GC-MS). In vitro antioxidant assessment was conducted based on DPPH, hydrogen peroxide (H2O2), nitric oxide (NO), and ferric ion (Fe3+) radical scavenging assays. The cytotoxicity of the oil against non-tumorigenic (HEK293) and cancerous (HepG2 and HeLa) cell lines was determined following the MTT cell viability assay. An in silico molecular docking analysis of the oil constituents was also performed. Six batches of EOs I–VI were afforded, comprising twenty-two major constituents, with aromatic Ar-turmerone being the most prominent compound. There was a marked improvement in the bioactivity of the oils upon repeated HD and as a combination. The batch VI oil exhibited the best activity, with a cytotoxicity (CC50) of 10.16 ± 1.69 µg/100 µL against the HepG2 cell line, which was comparable to 5-fluorouracil (standard, CC50 = 8.59 ± 1.33 µg/100 µL). In silico molecular docking suggested δ-curcumene, Ar-curcumene, Ar-turmerol, and Ar-turmerone among the promising compounds based on their high binding energy scores with NOX2, NF-κB, and mdm2 proteins. In conclusion, the oils from the turmeric–black cumin combined possess a considerable inhibition ability against free radicals, protein denaturation, and cancer proliferation. This study’s findings further underscore the effectiveness of turmeric–black cumin as a polyherbal medicinal ingredient.

This study investigates the impact of dry heat pretreatment on the functionality of soy, chickpea, and pea protein ingredients for use in texturized vegetable protein (TVP) production via low moisture extrusion. The protein powders were heat-treated at temperatures ranging from 80 °C to 160 °C to modulate the extent of protein denaturation and assess their effects on RVA pasting behavior, water absorption capacity (WAC), and color attributes. The results indicate that the pretreatment temperature significantly influenced the proteins’ functional properties, with an optimal temperature of 120 °C enhancing pasting properties and maintaining WAC, while a higher pretreatment temperature of 160 °C led to diminished ingredient functionality. Different protein sources exhibited distinct responses to heat pretreatment. The subsequent extrusion processing revealed significant changes in extrudate density and color, with increased density and darkness observed at higher pretreatment temperatures. This research provides insights into the interplay between protein sources, pretreatment conditions, and extrusion outcomes, highlighting the importance of controlled protein denaturation for developing high-quality, plant-based meat analogues. The findings have broad implications for the optimization of meat analogue manufacturing, with the aim of enhancing the sensory experience and sustainability of plant-based foods.

GdmCl and NaSCN are two strong chaotropic salts commonly used in protein folding and stability studies, but their microscopic mechanisms remain enigmatic. Here, by CD and NMR, we investigated their effects on conformations, stability, binding and backbone dynamics on ps-ns and µs-ms time scales of a 39-residue but well-folded WW4 domain at salt concentrations ≤200 mM. Up to 200 mM, both denaturants did not alter the tertiary packing of WW4, but GdmCl exerted more severe destabilization than NaSCN. Intriguingly, GdmCl had only weak binding to amide protons, while NaSCN showed extensive binding to both hydrophobic side chains and amide protons. Neither denaturant significantly affected the overall ps-ns backbone dynamics, but they distinctively altered µs-ms backbone dynamics. This study unveils that GdmCl and NaSCN destabilize a protein before the global unfolding occurs with differential binding properties and µs-ms backbone dynamics, implying the absence of a simple correlation between thermodynamic stability and backbone dynamics of WW4 at both ps-ns and µs-ms time scales.

Aquatic animal products are rich in protein, lipids, and moisture and are often stored at frozen temperature. However, aquatic animal products are prone to deterioration caused by ice crystal formation, lipid oxidation and protein denaturation. Quick freezing is crucial for preserving the quality of aquatic animal products by preventing the formation of large ice crystals. Liquid nitrogen quick-freezing (LNF) provides a fast-freezing rate, minimal ice crystal formation, preservation of product texture and nutritional properties, shelf-life extension, energy efficiency, and quality and safety improving. This review comprehensively illustrates the mechanism of LNF, the impact of LNF on qualities of aquatic animal products including flavor, texture, color, and nutrition. Additionally, LNF devices applied on aquatic animal products are also discussed. Furthermore, future prospects and research directions are suggested, including optimizing freezing processes, understanding the impact on nutritional value and considering sustainability and energy consumption. However, challenges such as freezing damage, cost considerations, and quality control issues for LNF application need to be addressed.

The water distribution have a profound influence on meat quality, and proteins play a critical role in water distribution. The water distribution detected with proton NMR and its relationship with protein related properties were investigated. Three populations of water were detected: bound water (T21, P21), immobilized water (T22, P22), and free water (T23, P23). The decreased T22 and T23 indicated an increase in water-holding capacity in both muscles from 3 days of aging. The P22 in cattle was higher than that in yak and the P23 in cattle was lower than that in yak, suggesting that cattle exhibited a greater water-holding capacity compared to yak. Moreover, postmortem aging affected muscle protein oxidation, denaturation, and degradation. Correlation analysis suggested that protein oxidation and denaturation caused muscle water loss and protein degradation could allow the muscle to retain water. It provides a basis for the optimization of quality of meat and products.

Background: Rheumatoid arthritis (RA) is an inflammation of joints with increased cellularity of synovial tissue. Allopathic drugs possess several adverse effects, which have led to increase in the utilization of herbal medicines. Polyherbal emulgel resolves the bioavailability issue associated with hydrophobic drugs and can be used effectively in the treatment of RA. Objectives: The present study aimed at the formulation of polyherbal emulgel, and evaluation of in vitro anti-inflammatory activity and in vivo antiarthritic activity. Methods: Seven emulgels F-1 to F-7 were optimally formulated. In vitro anti-inflammatory activity was determined using protein denaturation method employing Diclofenac sodium as the standard. In antiarthritic study Complete Freund's Adjuvant (CFA) model was used. The various parameters were assessed, like paw volume, body weight, hematological parameters, antioxidant parameters, Rheumatic factor (RF), and histopathological study of ankle joint. Results: F-4 and F-7 were found to be optimized formulations as compared to other formulations. The in vitro anti-inflammatory activity was found to be highest in F-4 with IC50 7.74 and F-7 with IC50 8.87 in comparison with Diclofenac sodium having IC50 57.0. Both formulations F-7 and F-4 showed a significant reduction in paw volume and normalization of body weights. The formulation F-7 even showed more potent antiarthritic activity than F-4 by decreasing white blood cells (WBC), lymphocytes, increasing packed cell volume (PCV), neutrophils, superoxide dismutase (SOD), catalase and decreasing malondialdehyde (MDA) levels in serum. This was further confirmed by histopathological study. Conclusion: As an anti-inflammatory agent, this newly developed emulgel was found to possess more therapeutic efficacy than commercially available diclofenac sodium.

Serum autoantibody profiles are unique to individuals and reflect the level and history of autoimmunity and tumor immunity. The identification of autoantibody biomarkers is critical for the development of immune monitoring systems for immune‐related disorders. Here, we present a practical method for large‐scale autoantibody discovery using total cellular proteins from cultured mammalian cells. We found that nucleic acid‐free and fully denatured water‐soluble total cellular proteins from mammalian cells were superior, allowing precise separation by reversed‐phase HPLC after preparing a large set of homogeneous total cellular proteins. After separating the proteins based on hydrophobicity, the fractionated samples were subjected to molecular mass analysis using conventional SDS‐PAGE. The resulting two‐dimensional gel electrophoresis was successfully employed for immune blotting and LC–MS/MS analysis. All procedures, including TRIzol‐based total cellular protein extraction, solubilization of denatured proteins, reversed‐phase HPLC separation, and SDS‐PAGE, were highly reproducible and easily scalable. We propose this novel two‐dimensional gel electrophoresis system as an alternative proteomics‐based methodology suitable for large‐scale autoantibody discovery. [ABSTRACT FROM AUTHOR]

This study was conducted on chicken pectoralis major muscle with different wooden breast severity in combination with different sampling locations to investigate the effects of wooden breast syndrome on protein traits and total myofiber area, and their associations. Contents of sarcoplasmic, salt-soluble myofibrillar and salt-insoluble protein and proportion of total myofiber area significantly declined with increasing severity in the superficial part of muscle, whereas the amount of heat-soluble/insoluble collagen and protein denaturation as well as the area of degenerated myofibers, connective tissue and cellular infiltrates increased. Myofibril protein content indicators showed strong positive correlations to total myofiber area. Moreover, PCA results indicated that severe wooden breast is positively linked to muscle collagen content and to protein denaturation. Our results suggest that decrease in sarcoplasmic and myofibrillar proteins is associated with reduction of myofiber area. In turn, the muscle fibers are replaced by connective tissue, accompanied by excessive myofibrillar and sarcoplasmic protein denaturation. [ABSTRACT FROM AUTHOR]

The vanilloid receptor TRPV1 is an exquisite nociceptive sensor of noxious heat, but its temperature-sensing mechanism is yet to define. Thermodynamics dictate that this channel must undergo an unusually energetic allosteric transition. Thus, it is of fundamental importance to measure directly the energetics of this transition in order to properly decipher its temperature-sensing mechanism. Previously, using submillisecond temperature jumps and patch-clamp recording, we estimated that the heat activation for TRPV1 opening incurs an enthalpy change on the order of 100 kcal/mol. Although this energy is on a scale unparalleled by other known biological receptors, the generally imperfect allosteric coupling in proteins implies that the actual amount of heat uptake driving the TRPV1 transition could be much larger. In this paper, we apply differential scanning calorimetry to directly monitor the heat flow in TRPV1 that accompanies its temperature-induced conformational transition. Our measurements show that heat invokes robust, complex thermal transitions in TRPV1 that include both channel opening and a partial protein unfolding transition and that these two processes are inherently coupled. Our findings support that irreversible protein unfolding, which is generally thought to be destructive to physiological function, is essential to TRPV1 thermal transduction and, possibly, to other strongly temperature-dependent processes in biology [ABSTRACT FROM AUTHOR]

The plant of Bajakah tampala (Spatholobus littoralis Hassk) has been utilized in traditional medication. Previous studies have proven the existence of in vivo anti-inflammatory activities of Bajakah plant (S. littoralis) in lowering the degree of carrageenan-induced paw oedema in mice. This study aims to determine the anti-inflammatory mechanism of S. littoralis extract in vitro through an approach of enzyme inhibition involved in the inflammatory reaction. The concentration of ethanol extract of Bajakah used was 0.1; 0.2; 0.4; 0.8; 1.6 mg/ml. The parameters measured were lipoxygenase enzyme inhibition, protein denaturation inhibition, protease enzyme inhibition, as well as plasma membrane stabilization. The results of the study showed the potential of the ethanol extract of Bajakah stems in inhibiting the inflammatory process viewed from the ability to inhibit inflammation-related enzymes. S. littoralis extract concentration of 1.6 mg/ml showed the best inhibition of the protein denaturation process (75.9%), the inhibition of trypsin protease enzyme (26.1%) and the stability of erythrocyte membrane (93.7%). However, the extracts of S. littoralis did not provide inhibition for the lipoxygenase enzyme in the range of 0.2-3.8%. This study proves the role of S. littoralis extract in the anti-inflammatory mechanism. It has the potential to be developed into standardized herbs. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Proteins fold on relatively smooth free energy landscapes which are biased toward the native state, but even simple topologies which fold rapidly can experience roughness on their free energy landscape. The details of these interactions are difficult to elucidate experimentally. Closely related to the problem of deciphering the details of the free energy landscape is the problem of defining the interactions in the denatured state ensemble (DSE) which is populated under native conditions, that is, under conditions where the native state is stable. The DSE of many proteins deviates from random coil models, but quantifying and defining the energetics of the transiently populated interactions in this ensemble is extremely challenging. Characterization of the DSE of proteins which fold to compact structures is also relevant to studies of intrinsically disordered proteins (IDPs) since interactions in the dynamic ensemble populated by IDPs can modulate their behavior. Here we show how experimental thermodynamic and pKa measurements can be combined with computational thermodynamic integration to quantify interactions in the DSE. We show that non-native side chain interactions can stabilize native backbone structure in the DSE and demonstrate that that even rapidly folding proteins can form energetically significant non-native interactions in their DSE. As an example, we characterize a non-native salt bridge that stabilizes local native backbone structure in the DSE of a widely studied fast-folding protein, the villin headpiece helical domain. The combined computational experimental approach is applicable to other protein unfolded states and provides insight that is impossible to obtain with either method alone.

Newly-translated glycoproteins in the endoplasmic reticulum (ER) often undergo cycles of chaperone binding and release in order to assist in folding. Quality control is required to distinguish between proteins that have completed native folding, those that have yet to fold, and those that have misfolded. Using quantitative modeling, we explore how the design of the quality-control pathway modulates its efficiency. Our results show that an energy-consuming cyclic quality-control process, similar to the observed physiological system, outperforms alternative designs. The kinetic parameters that optimize the performance of this system drastically change with protein production levels, while remaining relatively insensitive to the protein folding rate. Adjusting only the degradation rate, while fixing other parameters, allows the pathway to adapt across a range of protein production levels, aligning with in vivo measurements that implicate the release of degradation-associated enzymes as a rapid-response system for perturbations in protein homeostasis. The quantitative models developed here elucidate design principles for effective glycoprotein quality control in the ER, improving our mechanistic understanding of a system crucial to maintaining cellular health.

Background: Oldenlandia corymbosa and Oldenlandia umbellata are well-known medicinal plants in various traditional systems of medicine and used to treat bronchitis, asthma, tuberculosis, constipation, and leprosy. We evaluated the phytochemical content, antioxidant potential, enzyme inhibitory action, anti-inflammatory, and antibacterial activities of the whole plant extracts of O. corymbosa and O. umbellata due to their therapeutic importance. Methods: The phytochemical analysis includes qualitative analysis and quantification of total phenolics, flavonoids, tannins, flavonols, proanthocyanidins, and vitamin E. Enzyme inhibitory assays were studied using α-amylase and α-glucosidase enzymes and anti-inflammatory activity was determined by egg albumin denaturation assay. Antioxidant potential was estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethyl benzothiozoline-6-sulfonic acid) diammonium salt (ABTS), ferric reducing antioxidant power (FRAP), hydroxyl radical, superoxide, nitric oxide, metal chelating, and phosphomolybdenum assays. Minimum inhibitory concentrations of extracts were studied against ten bacterial strains by the microdilution method. Results: The aqueous extract of O.umbellata showed a higher extract yield (5.0%). The highest amount of total phenolics and flavonoids were observed in the ethanolic extract of O.umbellata (77.23±0.46 mg GAE/g) and O.corymbosa (19.01±0.26 mg GAE/g). Ethanolic extract of O.umbellata (IC50 of 31.71±0.32 µg/mL) and aqueous extract of O.corymbosa (30.53±1.83 µg/mL) showed notable α-amylase inhibitory effect and petroleum ether extract of both plants observed good inhibition against α-glucosidase enzyme. Likewise, petroleum ether extract of O.umbellata (IC50 of 57.16±1.88 µg/mL) showed a moderate anti-inflammatory effect. In all extracts, considerable antioxidant potential was recorded specially with aqueous extract in the nitric oxide scavenging assay with an IC50 of 40.72±1.25 µg/mL. Ethanolic extract of O.umbellata and petroleum ether extract of O.corymbosa (MIC of 56.25 µg/mL) showed good antibiotic potency in lower concentrations which proves these two valuable herb's potential in herbal preparations. Conclusions: The results of the study provide a basis for further studies aiming to evaluate the possibilities of using the O. umbellata and O. corymbosa as natural sources of antioxidants, enzyme inhibitory, and antibacterial agents. Further studies could be directed to exploit these plants in experimental animal models as potential pharmaceutical agents.

Storage via freezing remains the most effective approach for fish preservation. However, lipid oxidation and protein denaturation still occur during storage, along with nutritional loss. The extent of lipid alteration and protein denaturation are associated with human health defects. To precisely predict common carp (Cyprinus carpio) nutritional quality change during frozen storage, here, we first determined lipid oxidation and hydrolysis and protein denaturation of common carp fillets during 17 weeks of frozen preservation at 261 K, 253 K, and 245 K. Results showed that the content of thiobarbituric acid reactive substances (TBARS) and free fatty acids (FFA) were significantly increased. However, salt-soluble protein (SSP) content, Ca2+-ATPase activity, and total sulfhydryl (SH) content kept decreasing during frozen storage, with SSP content decreasing by 64.82%, 38.14%, and 11.24%, respectively, Ca2+-ATP enzyme activity decreasing to 12.50%, 18.52%, and 28.57% Piμmol/mg/min, and SH values decreasing by 70.71%, 64.92%, and 56.51% at 261 K, 253 K, and 245 K, respectively. The values at 261 K decreased more than that at 253 K and 245 K (p < 0.05). Ca2+-ATPase activity was positively correlated (r = 0.96) with SH content. Afterwards, based on the results of the above chemical experiments, we developed a radial basis function neural network (RBFNN) to predict the modification of lipid and protein of common carp fillets during frozen storage. Results showed that all the relative errors of experimental and predicted values were within ±10%. In summary, the quality of common carp can be well protected at 245 K, and the established RBFNN could effectively predict the quality of the common carp under frozen conditions at 261–245 K. [ABSTRACT FROM AUTHOR]

Skin diseases are a common problem faced by people worldwide, and there is a growing demand for natural and safe solutions to treat them. Nanogels are a promising drug delivery system due to their small size, high surface area, and ability to encapsulate both hydrophilic and hydrophobic compounds. In this study, we aimed to optimize and evaluate the parameters of a herbal-based nanogel formulation for the treatment of skin diseases. The nanogel formulation was prepared using a combination of natural polysaccharides, namely chitosan and sodium alginate, and a herbal extract of neem leaves. The optimization parameters included varying the concentrations of chitosan, sodium alginate, and neem extract, and the pH of the formulation. The optimized formulation was evaluated for its physicochemical properties, drug release profile, stability, and skin irritation potential. The results showed that the optimal nanogel formulation had a particle size of 200 nm, a zeta potential of +25 mV, and a drug entrapment efficiency of 80%. The drug release profile was found to be sustained, with 60% of the drug being released over 8 hours. The stability studies showed that the formulation was stable for 3 months at 4°C. The skin irritation studies indicated that the nanogel formulation was non-irritating and safe for topical application. The herbal-based nanogel formulation developed in this study has the potential to be a safe and effective treatment option for skin diseases. Further studies are required to investigate its efficacy in vivo and in clinical trials. [ABSTRACT FROM AUTHOR]

The effect of previous frozen storage (−18 °C for 6 months) and different coating media (aqueous: water and brine; oily: sunflower, refined olive, and extra-virgin olive oils) on the essential macroelement and trace element content of canned Atlantic mackerel (Scomber scombrus) was studied. Previous frozen storage led to an increased (p < 0.05) content of canned samples of K (oil-coated samples) and Ca (all coating conditions) and to a decreased (p < 0.05) content of P (aqueous-coating samples) and S (water- and oil-coated samples). For trace elements, a content increase (p < 0.05) in Cu and Se (brine-canned samples) and Mn (water- and refined-olive-oil-coated samples) was detected in canned fish muscle with frozen storage. Concerning the coating effect, aqueous-coating samples showed lower (p < 0.05) Mg, P, S, K, and Ca contents than their corresponding oil-coated samples. For trace elements, lower average contents were found for Co, Cu, Mn, Se, and Fe in aqueous-coating fish muscle when compared to their counterparts coated in oily media. Content changes in the different elements in canned fish muscle are discussed based on interactions with other tissue constituents and modifications that such constituents undergo during processing (i.e., protein denaturation, liquor losses from the muscle, lipid changes). [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, we present the first detailed analysis of the hydro-distilled essential oil (HDEO) of the inflorescence heads of Echinops polyceras Boiss. (Asteraceae) from the flora of Jordan, offering observations at different growth (pre-flowering, full-flowering and post-flowering) stages. Additionally, we investigated the methanolic extract obtained from the aerial parts of the plant material at the full flowering stage in order to determine its inhibitory activity in terms of COX and protein denaturation and evaluate its antimicrobial effects against S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria. Performing GC/MS analysis of HDEO, obtained from the fresh inflorescence heads at the different growth stages, resulted in the identification of 192 constituents. The main class of compounds detected in these three stages comprised aliphatic hydrocarbons and their derivatives, which amounted to 50.04% (pre-flower), 40.28% (full-flower) and 41.34% (post-flower) of the total composition. The oils also contained appreciable amounts of oxygenated terpenoids, primarily sesquiterpenoids and diterpenoids. The pre-flowering stage was dominated by (2E)-hexenal (8.03%) in addition to the oxygenated diterpene (6E,10E)-pseudo phytol (7.54%). The full-flowering stage primarily contained (6E,10E)-pseudo phytol (7.84%), β-bisabolene (7.53%, SH) and the diterpene hydrocarbon dolabradiene (5.50%). The major constituents detected in the HDEO obtained at the post-flowering stage included the oxygenated sesquiterpenoid intermedeol (5.53%), the sesquiterpene hydrocarbon (E)-caryophyllene (5.01%) and (6E,10E)-pseudo phytol (4.47%). The methanolic extract obtained from air-dried aerial parts of E. polyceras displayed more COX-2 inhibition than COX-1 inhibition at a concentration level of 200 µg/mL. The extract exhibited a capacity to inhibit protein denaturation that was comparable with respect to the activity of diclofenac sodium and displayed moderate levels of antimicrobial activity against both bacterial species. The current results demonstrate the need to perform further detailed phytochemical investigations to isolate and characterize active constituents. [ABSTRACT FROM AUTHOR]

The objective of the present study is to evaluate the pharmacological actions of earlier reported metabolites (1-5), and semi-synthetic analogs (4a-e) from acetone extract of Ramalina leiodea. The Acetone extract of Ramalina leiodea were screened for antioxidant, anti-inflammatory, anticancer, and acute toxicity studies. The antioxidant results exhibited that compound 4e showed effective inhibitory ability against ferric ions, 2,2-diphenyl-1-picrylhydrazyl and superoxide free radicals with 50 % inhibition value of 28.50, 27.0, and 25.0 µg/ml, respectively. Also, among all the samples, 4e revealed good inhibition of albumin denaturation of 105 µg/ml (IC50 value). Additionally, the median lethal dosage of acetone extract of Ramalina leiodea was observed to be above 2000 mg/Kg body weight. Also, the in vivo anti inflammatory studies of acetone extract of Ramalina leiodea exhibited a noticeable reduction of edema in rat paw at both low and high dosage when compared to indomethacin. From the sulforhodamine B assay, it is concluded that 2 and 4b displayed a noteworthy degree of specificity against tested series of cell lines. On the other hand, all tested samples displayed a low degree of specificity against normal cells. To conclude, Ramalina leiodea could be the best source for bioactive agents for the management of oxidative stress, inflammation, and cancer. The objective of the present study is to evaluate the pharmacological actions of earlier reported metabolites (1-5), and semi-synthetic analogs (4a-e) from acetone extract of Ramalina leiodea. The Acetone extract of Ramalina leiodea were screened for antioxidant, anti-inflammatory, anticancer, and acute toxicity studies. The antioxidant results exhibited that compound 4e showed effective inhibitory ability against ferric ions, 2,2-diphenyl-1-picrylhydrazyl and superoxide free radicals with 50 % inhibition value of 28.50, 27.0, and 25.0 µg/ml, respectively. Also, among all the samples, 4e revealed good inhibition of albumin denaturation of 105 µg/ml (IC50 value). Additionally, the median lethal dosage of acetone extract of Ramalina leiodea was observed to be above 2000 mg/Kg body weight. Also, the in vivo anti inflammatory studies of acetone extract of Ramalina leiodea exhibited a noticeable reduction of edema in rat paw at both low and high dosage when compared to indomethacin. From the sulforhodamine B assay, it is concluded that 2 and 4b displayed a noteworthy degree of specificity against tested series of cell lines. On the other hand, all tested samples displayed a low degree of specificity against normal cells. To conclude, Ramalina leiodea could be the best source for bioactive agents for the management of oxidative stress, inflammation, and cancer. [ABSTRACT FROM AUTHOR]

Proteins are molecular machines whose function depends on their ability to achieve complex folds with precisely defined structural and dynamic properties. The rational design of proteins from first-principles, or de novo, was once considered to be impossible, but today proteins with a variety of folds and functions have been realized. We review the evolution of the field from its earliest days, placing particular emphasis on how this endeavor has illuminated our understanding of the principles underlying the folding and function of natural proteins, and is informing the design of macromolecules with unprecedented structures and properties. An initial set of milestones in de novo protein design focused on the construction of sequences that folded in water and membranes to adopt folded conformations. The first proteins were designed from first-principles using very simple physical models. As computers became more powerful, the use of the rotamer approximation allowed one to discover amino acid sequences that stabilize the desired fold. As the crystallographic database of protein structures expanded in subsequent years, it became possible to construct proteins by assembling short backbone fragments that frequently recur in Nature. The second set of milestones in de novo design involves the discovery of complex functions. Proteins have been designed to bind a variety of metals, porphyrins, and other cofactors. The design of proteins that catalyze hydrolysis and oxygen-dependent reactions has progressed significantly. However, de novo design of catalysts for energetically demanding reactions, or even proteins that bind with high affinity and specificity to highly functionalized complex polar molecules remains an importnant challenge that is now being achieved. Finally, the protein design contributed significantly to our understanding of membrane protein folding and transport of ions across membranes. The area of membrane protein design, or more generally of biomimetic polymers that function in mixed or non-aqueous environments, is now becoming increasingly possible.

Noscapine hydrochloride (benzyl-isoquinoline antitussive alkaloid) is an opium derivative and generally used as a cough suppressant. Numerous studies on noscapine hydrochloride have reported that it has potent anti-inflammatory activity. However, the mechanisms by which it exerts an anti-inflammatory function is not well understood. Protein denaturation is the primary step that leads to the organ destruction and permanent arthritic disability. The above-mentioned facts provided the ground to plan this study using different in-vitro and in-vivo approaches. RT-qPCR and ELISA assays were used to assess the inflammatory markers related to protein denaturation in complete adjuvant persuaded rheumatism in Sprague - Dawley rats. The results were collected as paw volume and body weight changes, arthritic scoring and serum antioxidant enzymes assays. These findings demonstrated that all doses of noscapine hydrochloride (10, 20 and 40 mg/kg) studied in this study, significantly (p

The mechanism of urea's action in protein denaturation remains largely unknown. To provide an experimental basis for molecular dynamics (MD) simulations on urea-protein interactions, we investigated the effect of urea on human intestinal fatty acid binding protein (hIFABP) by nuclear magnetic resonance (NMR). Hydrogen-deuterium exchange (HDX) rates at ≤ 2 M urea indicate that urea affects hIFABP in a residue-specific manner via direct urea-protein interactions and preferentially weakens hydrogen bonds between highly protected amides. Residue-specific effects of urea on NMR peak intensities and chemical shifts further support the presence of direct urea-protein interactions. Two-dimensional (2D) water-rotating frame Overhauser enhancement (ROE) data shows one protein-bound water molecule in contact with Val66 and Trp82, one putative bound water molecule in interaction with Thr76 and E-F loop, and that urea at low concentrations cannot displace these protein-bound water molecules. Our urea-nuclear Overhauser effect (NOE) experiments using 15N-urea further show no tightly protein-bound urea molecules. Our results thus suggest specific, but weak or transient, urea-protein interactions, supporting the direct interaction model of urea denaturation.

The use of the synthetic drugs has increased in the last few decades; however, these drugs exhibit various side effects. Scientists are therefore seeking alternatives from natural sources. Commiphora gileadensis has long been used to treat various disorders. It is commonly known as bisham or balm of Makkah. This plant contains various phytochemicals, including polyphenols and flavonoids, with biological potential. We found that steam-distilled essential oil of C. gileadensis exhibited higher antioxidant activity (IC50, 22.2 µg/mL) than ascorbic acid (IC50, 1.25 µg/mL). The major constituents (>2%) in the essential oil were β-myrcene, nonane, verticiol, β-phellandrene, β-cadinene, terpinen-4-ol, β-eudesmol, α-pinene, cis-β-copaene and verticillol, which might be responsible for the antioxidant and antimicrobial activity against Gram-positive bacteria. The extract of C. gileadensis exhibited inhibitory activity against cyclooxygenase (IC50, 450.1 µg/mL), xanthine oxidase (251.2 µg/mL) and protein denaturation (110.5 µg/mL) compared to standard treatments, making it a viable treatment from a natural plant source. LC-MS analysis revealed the presence of phenolic compounds such as caffeic acid phenyl ester, hesperetin, hesperidin, chrysin and transient amounts of catechin, gallic acid, rutin and caffeic acid. The chemical constituents of this plant can be explored further to investigate its wide variety of therapeutic potential. [ABSTRACT FROM AUTHOR]

The post-mortem rigid of farmed rainbow trout (Oncorhynchus mykiss) affects the texture of the meat and might even be risky for microorganisms, undermining the popularity of frozen filets among consumers. This study investigated the importance of different conditions (0°C, 4°C, and 25°C for 0–4 days) and physicochemical characteristics of rainbow trout filet storage on fish’s characteristics, freshness, quality, and shelf-life. Results showed that the fish easily underwent rigor mortis and resolution of rigor mortis when stored at 25°C. However, rigor mortis was more likely to occur under storage at 0°C than at 4°C [with 100 kV/m high voltage electrostatic fields (HVEF)] due to low-temperature stimulation, but resolution of rigor mortis began to appear after 24 h of storage at either temperature. The protein solubility and gel strength of fish stored at 25°C continued to decrease due to thermal denaturation, and those of fish stored at 4°C and 0°C also showed a decrease owing to rigor mortis and then an increase when rigor mortis disappeared. The K values increased rapidly at 25°C and reached 61% at 14 h. Under storage at 4°C and 0°C, the K values only slightly increased before resolution of rigor mortis. However, the K-values did not exceed 40% for 4 days post-resolution of rigor mortis. Differential Scanning Calorimetry analysis and tissue sectioning showed that protein denaturation and separation between muscle fibers persisted during storage at various temperatures, most notably at 25°C. It is important to note that storing at 0°C for 96 h did not result in any significant changes in the molecular protein composition. Moreover, the muscle tissue remained in excellent condition compared to storage at 25°C and 4°C. Additionally, there was no significant difference in the total viable count (TVC) and psychrophilic bacteria between storage at 0°C and 4°C, considered safe for food consumption. These promising findings are conveyed in a circular economy based on the food industry, particularly adequate raw materials, stable prices, measures to reduce food loss and waste, and contributing to developing efficient, diverse, and sustainable food processing systems.

Chemical chaperones are low-molecular-weight compounds that suppress protein aggregation. They can influence different stages of the aggregation process—the stage of protein denaturation, the nucleation stage and the stage of aggregate growth—and this may lead to a change in the aggregation kinetic regime. Here, the possibility of changing the kinetic regime in the presence of a chemical chaperone 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) was investigated for a test system based on the thermally induced aggregation of yeast alcohol dehydrogenase (yADH) at 56 °C. According to differential scanning calorimetry data, 2-HP-β-CD did not affect the stage of the protein molecule unfolding. Dynamic light scattering data indicated changes in the aggregation kinetics of yADH during the nucleation and aggregate growth stages in the presence of the chaperone. The analysis of kinetic curves showed that the order of aggregation with respect to protein (nc), calculated for the stage of aggregate growth, changed from nc = 1 to nc = 2 with the addition of 100 mM 2-HP-β-CD. The mechanism of 2-HP-β-CD action on the yADH thermal aggregation leading to a change in its kinetic regime of aggregation is discussed.

One gene can give rise to many functionally distinct proteoforms, each of which has a characteristic molecular mass. Top-down mass spectrometry enables the analysis of intact proteins and proteoforms. Here members of the Consortium for Top-Down Proteomics provide a decision tree that guides researchers to robust protocols for mass analysis of intact proteins (antibodies, membrane proteins and others) from mixtures of varying complexity. We also present cross-platform analytical benchmarks using a protein standard sample, to allow users to gauge their proficiency.

The dimensions that unfolded proteins, including intrinsically disordered proteins (IDPs), adopt in the absence of denaturant remain controversial. We developed an analysis procedure for small-angle X-ray scattering (SAXS) profiles and used it to demonstrate that even relatively hydrophobic IDPs remain nearly as expanded in water as they are in high denaturant concentrations. In contrast, as demonstrated here, most fluorescence resonance energy transfer (FRET) measurements have indicated that relatively hydrophobic IDPs contract significantly in the absence of denaturant. We use two independent approaches to further explore this controversy. First, using SAXS we show that fluorophores employed in FRET can contribute to the observed discrepancy. Specifically, we find that addition of Alexa-488 to a normally expanded IDP causes contraction by an additional 15%, a value in reasonable accord with the contraction reported in FRET-based studies. Second, using our simulations and analysis procedure to accurately extract both the radius of gyration (Rg) and end-to-end distance (Ree) from SAXS profiles, we tested the recent suggestion that FRET and SAXS results can be reconciled if the Rg and Ree are "uncoupled" (i.e., no longer simply proportional), in contrast to the case for random walk homopolymers. We find, however, that even for unfolded proteins, these two measures of unfolded state dimensions remain proportional. Together, these results suggest that improved analysis procedures and a correction for significant, fluorophore-driven interactions are sufficient to reconcile prior SAXS and FRET studies, thus providing a unified picture of the nature of unfolded polypeptide chains in the absence of denaturant.

The scavenging capacity of glycoprotein DMBT1 helps defend mucosal epithelia against microbes. DMBT1 binding to multiple bacterial species involves its conserved Scavenger Receptor Cysteine-Rich (SRCR) domains, localized to a 16-mer consensus sequence peptide, SRCRP2. Previously, we showed that DMBT1 bound Pseudomonas aeruginosa pili, and inhibited twitching motility, a pilus-mediated movement important for virulence. Here, we determined molecular characteristics required for twitching motility inhibition. Heat-denatured DMBT1 lost capacity to inhibit twitching motility and showed reduced pili binding (~40%). Size-exclusion chromatography of Lys-C-digested native DMBT1 showed that only high-Mw fractions retained activity, suggesting involvement of the N-terminal containing repeated SRCR domains with glycosylated SRCR-Interspersed Domains (SIDs). However, individual or pooled consensus sequence peptides (SRCRPs 1 to 7) showed no activity and did not bind P. aeruginosa pili; nor did recombinant DMBT1 (aa 1-220) or another SRCR-rich glycoprotein, CD163. Enzymatic de-N-glycosylation of DMBT1, but not de-O-glycosylation, reduced its capacity to inhibit twitching motility (~57%), without reducing pili binding. Therefore, DMBT1 inhibition of P. aeruginosa twitching motility involves its N-glycosylation, its pili-binding capacity is insufficient, and it cannot be conferred by the SRCR bacteria-binding peptide domain, either alone or mixed with other unlinked SRCRPs, suggesting an additional mechanism for DMBT1-mediated mucosal defense.

Inflammation is a normal protective reaction against tissue damage caused by physical injury, harmful chemicals, and protein denaturation. Protein denaturation is a process in which proteins lose their tertiary structure and secondary structure due to foreign substances, external compounds, such as strong acids, strong bases, organic salts, organic solvents, and heating. The purpose of this study was to determine the anti-inflammatory activity of ethanol extract and ethyl acetate fraction of the seed coat of Kebiul (Caesalpinia bonduc L.) by calculating the IC50 value of protein denaturation in the sample. The results of the phytochemical test of the ethanol extract of Kebiul seeds contained flavonoids, alkaloids, terpenoids, steroids, saponins, and tannins, while the ethyl acetate fraction only contained tannins and alkaloids. The results of the anti-inflammatory test showed that the highest percent inhibition value of sodium diclofenac, ethanol extract, and ethyl acetate fraction, respectively, at a concentration of 20 ppm was 84.8%; 84.1%; and 50%. The IC50 values ​​of sodium diclofenac, ethanol extract, and ethyl acetate fraction were 5.4 μg/mL; 9.9 μg/mL; and 13.3 μg/mL, respectively. The three samples had percent inhibition values exceeding 20% which indicated that all three can be used as an anti-inflammatory. Keywords: anti-inflammatory, protein denaturation, Caesalpinia bonduc L.

Blue light with a wavelength of 400–470 nm is the composition of the visible light. However, in recent years, blue light contributed the most significance to light pollution due to the artificial light at night. Previously, we have demonstrated that the Asian citrus psyllid (ACP), Diaphorina citri, an important pest in citrus production, has significant positive phototaxis with a light-emitting diode light of 400 nm. In this study, ACP with positive phototactic behavior to 400 nm light (PH) and non-phototactic behavior to 400 nm light (NP) were collected, individually. Transcriptome dynamics of head tissues of PH and NP groups were captured by using RNA-sequencing technology, respectively. Forty-three to 46 million clean reads with high-quality values were obtained, and 1773 differential expressed genes (DEGs) were detected. Compared with the NP group, there were 841 up-regulated DEGs and 932 down-regulated DEGs in the PH group. Eight pathways were significantly enriched in the PH group in the KEGG database, while 43 up-regulated pathways and 25 down-regulated pathways were significantly enriched in the PH group in the GO database. The DGE approach was reliable validated by real time quantitative PCR. Results indicated that the blue light acted as an abiotic stress causing physiological and biochemical responses such as oxidative stress, protein denaturation, inflammation and tumor development in ACPs. Additionally, the light was absorbed by photoreceptors of ACPs, and converted into electrical signal to regulate neuromodulation. This study provides basic information for understanding the molecular mechanisms of ACP in response to blue light and provides a reference for further studies to elucidate phototactic behavior.

We report non-contact laser-based Brillouin light-scattering (BLS) spectroscopy measurements of the viscoelastic properties of hyperthermally radiofrequency (RF)-heated and ablated bovine liver and chicken flesh tissues with embedded gold nanoparticles (AuNPs). The spatial lateral profile of the local surface temperature in the flesh samples during their hyperthermia was measured through optical backscattering reflectometry (OBR) using Mg–silica-NP-doped sensing fibers distributed with an RF applicator and correlated with viscoelastic variations in heat-affected and ablated tissues. Substantial changes in the tissue stiffness after heating and ablation were directly related to their heat-induced structural modifications. The main proteins responsible for muscle elasticity were denatured and irreversibly aggregated during the RF ablation. At T > 100 °C, the proteins constituting the flesh further shrank and became disorganized, leading to substantial plastic deformation of biotissues. Their uniform destruction with larger thermal lesions and a more viscoelastic network was attained via AuNP-mediated RF hyperthermal ablation. The results demonstrated here pave the way for simultaneous real-time hybrid optical sensing of viscoelasticity and local temperature in biotissues during their denaturation and gelation during hyperthermia for future applications that involve mechanical- and thermal-property-controlled theranostics. [ABSTRACT FROM AUTHOR]