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In this review, the physicochemical and conformational changes of myofibrillar proteins (MPs) of freeze-induced mince-based aquatic foods were comprehensively summarized in depth. Studies have demonstrated that temperature fluctuation and long-time freezing negatively affect food quality, resulting in texture alteration, drip fluid, flavor degradation, and nutrition loss due to MPs denaturation, aggregation, and oxidation. Attempts have been made in ice-recrystallization inhibition, freezing point depression, and ice shape and growth control for better cryopreservation. Moreover, to further minimize the quality deterioration, cryoprotectants were acknowledged to reduce the denaturation and aggregation of the MPs effectively. Recently, interest in novel functional ingredients, including oligosaccharides, protein hydrolysates, and natural polyphenols demonstrated excellent cryoprotective effects while avoiding health concerns and undesirable flavor caused by traditional sugar-based or phosphates-based cryoprotectants. Therefore, the present review provides a systematic overview of these low molecular weight multifunctional substances with a particular sequence and highlights their underlying mechanism in the inhibition of ice recrystallization the stabilization of MPs. [ABSTRACT FROM AUTHOR]

According to the Hofmeister series, thiocyanate is the strongest "salting in" anion. In fact, it has a strong denaturant activity against the native state of globular proteins. A molecular level rationalization of the Hofmeister series is still missing, and therefore the denaturant activity of thiocyanate also awaits a robust explanation. In the last years, different types of experimental studies have shown that thiocyanate is capable to directly interact with both polar and nonpolar groups of polypeptide chains. This finding has been scrutinized via a careful computational procedure based on density functional theory approaches. The results indicate that thiocyanate is able to make H‐bonds via both the nitrogen and sulfur atom, and to make strong van der Waals interactions with almost all the groups of polypeptide chains, regardless of their polarity. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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

Freezing is commonly used to extend the shelf life of meat and meat products but may impact the overall quality of those products by inducing structural changes in myofibrillar proteins (MPs) through denaturation, chemical modification, and encouraging protein aggregation. This review covers the effect of freezing on the denaturation of MPs in terms of the effects of ice crystallization on solute concentrations, cold denaturation, and protein oxidation. Freezing-induced denaturation of MPs begins with ice crystallization in extracellular spaces and changes in solute concentrations in the unfrozen water fraction. At typical temperatures for freezing meat (lower than −18 °C), cold denaturation of proteins occurs, accompanied by an alteration in their secondary and tertiary structure. Moreover, the disruption of muscle cells triggers the release of cellular enzymes, accelerating protein degradation and oxidation. To minimize severe deterioration during the freezing and frozen storage of meat, there is a vital need to use an appropriate freezing temperature below the glass transition temperature and to avoid temperature fluctuations during storage to prevent recrystallization. Such an understanding of MP denaturation can be applied to determine the optimum freezing conditions for meat products with highly retained sensory, nutritional, and functional qualities. [ABSTRACT FROM AUTHOR]

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]

Summary: The current study was designed to supersede the meat protein with pulse‐based proteins and to determine the suitability of the processing method for commercialisation of plant protein meat analogues. The pulse protein concentrates (PPCs) were extracted from green gram, horse gram and cowpea using alkaline/isoelectric precipitation method. The PPCs were subjected for physicochemical, morphological, GC–MS and thermal analysis. The PPCs of green gram to horse gram to cowpea were used in the ratio of (20:20:20) T1, (30:15:15) T2 and (15:20:15) T3 to prepare deep‐fried meatballs. All the PPCs exhibited collapsed and wrinkled surface. The horse gram protein concentrates exhibited the highest denaturation temperature (Td °C) 89.50 ± 2.57 and enthalpy (ΔH (J g−1)) (287.73 ± 9.64) iterating better thermal stability compared to other samples. FTIR spectra indicated the presence of O–H stretching wide bands for mutton deep‐fried meatballs (3321.22 cm−1) and plant‐based deep‐fried meatballs (3288.28 cm−1), whereas PPCs in the region of (3275–3278 cm−1). Two C‐H bands and the main secondary structural components such as α‐helix, β‐sheet, β‐turn and random coil of PPCs were observed in the region of 1600–1700 cm−1. Amide N–H bending (1400–1500 cm−1) and the C–O stretching bands (1000–1300 cm−1) were observed for all the samples. The plant‐based deep‐fried meatball formulated at the ratio of 20:20:20 (T1) was closely related to the mutton deep‐fried meatballs in terms of organoleptic properties (colour, texture, juiciness and overall acceptability), colour properties (L* and b*) and textural properties such as hardness, adhesiveness and cohesiveness. These findings will open new research horizons in this area and pave the way for the commercialisation of meat substitutes, which will reduce the environmental impact and carbon footprint. [ABSTRACT FROM AUTHOR]

The objective of this study is to determine the antiarthritic activity of the aqueous and hydroalcoholic extracts of Linum usitatissimum L. seeds in vitro, as well as the phytochemical screening and determination of the flavonoid and flavonol content in the extracts. Phytochemical analysis of Linum usitatissimum seeds revealed the presence of sterols, tannins, flavonoids, phenols, and alkaloids in the aqueous and hydroalcoholic extracts. The flavonoid contents were 06.91 ± 0.38 and 04.85 ± 0.05 mg QE/g extract for the hydroalcoholic and aqueous extracts, respectively. For the flavonol assay, the contents are 04.53 ± 0.25 mg QE/g for the hydroalcoholic extract and 04.51 ± 0.03 mg QE/g for the aqueous extract. With the Bovin Serum Albumin (BSA) test, the aqueous extract showed the protective activity against BSA denaturation significantly (P < 0.05) the highest with an IC50 of 07.62 ± 1.56 mg/ml; on the other hand, the hydroalcoholic extract of Linum usitatissimum seeds is revealed significantly (P < 0.05) the most active with the egg albumin denaturation test whose IC50 recorded is 36.86 ± 2.72 mg/ml. From the results obtained, it was found that the aqueous and hydroalcoholic extracts of Linum usitatissimum seeds possess protective activity in vitro against protein denaturation, which plays a role in the training of inflammatory and arthritic diseases. [ABSTRACT FROM AUTHOR]

• Anatase Aw-TiO 2 NPs showed a spherical shape and a size range of 3–20 nm. • Aw-TiO 2 NPs significantly decreased the viability of A375 and MCF-7 cancer cells. • Aw-TiO 2 NPs induced excessive ROS generation and decreased MMP in cancer cells. • The anti-hemolytic effects of anatase Aw-TiO 2 NPs on horse-RBCs were demonstrated. • These NPs excellently inhibited the protein denaturation. The current research reports the physicochemical and biological properties of biosynthesized titanium dioxide nanoparticles (TiO 2 NPs) using bioactive compounds of Achillea wilhelmsii C. Koch extract (Aw-TiO 2 NPs). The cytotoxic impacts of Aw-TiO 2 NPs were assessed by the MTT method on A375 and MCF-7 cancer cell lines and normal skin fibroblast cell line and also by hemolysis test against horse red blood cells (RBCs). In addition, apoptotic activity was analyzed by assaying the generation of reactive oxygen species (ROS) and reduction of mitochondrial membrane potential (MMP). Additionally, the potential of Aw-TiO 2 NPs in inhibiting protein denaturation was evaluated. The prepared Aw-TiO 2 NPs with a size range of 3–20 nm and almost spherical shape showed an anatase crystallographic phase. A significant dose-dependent reduction in cancer cell viability was observed against anatase Aw-TiO 2 NPs with IC50 values of 12.5 and 25 µg/mL for A375 and MCF-7 cells, respectively. Aw-TiO 2 NPs induced the generation of excessive ROS (95.9 %-215.4 %) and decreased MMP (60.9 %-72 %) in cancer cells, which leads to the initiation of intrinsic apoptosis. Furthermore, anatase Aw-TiO 2 NPs had no hemolytic effects on horse-RBCs and excellently inhibited protein denaturation (80.8 % at 500 µg/mL). Therefore, anatase Aw-TiO 2 NPs can be a valuable and biocompatible candidate for biomedical applications and clinical uses. [ABSTRACT FROM AUTHOR]

Summary: The cryoprotective effects of chitooligosaccharide–gallic acid (COS–GA) complexes on peeled Pacific white shrimp were investigated and compared with single treatments of COS, GA and polyphosphate (PP) during 49 days of frozen storage at −5 °C. The data revealed a significant improvement in the antioxidant activity of COS through the conjugation of COS and GA. The soaking treatments of COS–GA and PP effectively maintained the water‐holding capacity and sensory properties of shrimp muscle compared with the water‐soaked shrimp (control). Furthermore, the COS–GA‐soaked shrimp samples exhibited significant inhibitory effects on the textural and chrominance deterioration of muscle tissues compared with the control samples. Chemical analyses demonstrated that the COS–GA treatment also preserved higher levels of myofibrillar protein content, total sulfhydryl content and Ca2+‐ATPase activity in the frozen shrimp samples. Histological observations indicated that the COS–GA soaking treatment effectively protected the integrity and stability of muscle tissues. Overall, COS–GA exhibited superior antioxidation and water‐retaining properties, stabilising the shrimp muscle during long‐term frozen storage. [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]

Protein denaturation during spray drying is critical for high-quality food powders. This study investigated the influence of particle size on protein denaturation using phycocyanin as a marker. The effect of particle size was investigated at three different air outlet temperatures, with the inlet air temperature held constant. For each temperature combination, different nozzles were utilized to obtain varying particle sizes. Denaturation increased with higher outlet air temperature and larger particle size, up to a size of 40 μm. This increase in denaturation with particle size was attributed to faster drying rates and the absence of denaturation once particles are dry. Particle size had a similar magnitude of effect as outlet air temperature. For larger particles, a plateau in denaturation was observed due to a prolonged constant drying rate regime. It can be assumed that conditions that retain phycocyanin are also suited for the retention for less thermolabile proteins. [ABSTRACT FROM AUTHOR]

We present a mathematical model for the full drying process of a single protein formulation droplet taking into account the convective impact arising from its levitation by a standing ultrasound wave. Using the finite element method allows us to compute the evaporation rate directly from the fully resolved heat and mass transfer within and around the levitated droplet. We apply our model to simulate the drying kinetics of pure water and aqueous phosphoglycerate kinase (PGK) droplets under various levitation and drying conditions. Empirical data from the literature are used to validate and discuss our numerical results. The acoustic streaming turns out to accelerate not only the first but also the second drying stage. Moreover, the dehydration of the protein molecules is found to be primarily responsible for their enzymatic inactivation throughout the drying process. [ABSTRACT FROM AUTHOR]

Protein denaturation is a common process in the food industry, which can impact food quality and safety. Computational Fluid Dynamics (CFD) is a powerful tool that can be used to predict protein denaturation in food products. In this review article, we present an overview of the application of CFD simulation in predicting protein denaturation in food products. We discuss the factors that influence protein denaturation, the importance of predicting protein denaturation, and the various numerical methods used in protein denaturation studies. The main focus of the article is the use of CFD simulation in predicting protein denaturation in selected food products, such as milk, meat, and eggs. We provide examples of numerical studies that have been conducted on these products, and we discuss the results and implications of these studies. The use of CFD simulation can help to optimize food processing conditions, improve food quality and safety, and reduce waste and costs in the food industry. Overall, this review article highlights the importance of using advanced computational tools such as CFD simulation in food science, research and development. The use of CFD simulation can predict protein denaturation in food products. Numerical studies were conducted on selected food products to analyze protein denaturation. CFD simulation provides a powerful tool for optimizing food processing technologies. The results from the numerical studies can be used to improve the quality and safety of food products. The application of CFD simulation can lead to more efficient and sustainable food production practices. [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]

Diosgenin (DGN) is a well-known steroidal sapogenin that is obtained from the hydrolysis of dioscin. The current research aimed to explore the anti-inflammatory and anti-arthritic potential of DGN alone and in combination with methotrexate (MTX). The in-vitro antioxidant, and anti-arthritic potential was assessed by protein denaturation and Human red blood cell membrane stabilization assays. The in-vivo anti-inflammatory effect was examined by carrageenan-induced paw edema and xylene-induced ear edema methods. The arthritis was induced in Wistar rats by inoculation of 0.1 ml Complete Freund's adjuvant in the left hind paw at day 1. The arthritic animals received MTX 1 mg/kg as standard, DGN at 5, 10, 20 mg/kg, and a combination treatment (DGN 20 mg/kg + MTX) was administered orally from 8 to 28th day while normal and disease control received normal saline. DGN at 1600 μg/ml exhibited the highest in-vitro activities in contrast to other tested concentrations. DGN at 20 mg/kg exhibited the maximum (p < 0.05–0.0001) inhibition of inflammation in carrageenan and xyleneinduced edema models. Treatment with DGN and MTX alone and in combination significantly reduced the paw diameter, body weight, arthritic index, and pain. It restored altered blood parameters and oxidative stress biomarkers in contrast to the diseased control rats. DGN profoundly (P < 0.0001) downregulated mRNA expression of TNF-α, IL-1β, NF-ĸβ, and COX-2 while upregulated IL-4 and -10 in treated rats. The combination of DGN with MTX showed the highest therapeutic efficacy than individual therapy, so it can be used as an adjunct for rheumatoid arthritis treatment. [ABSTRACT FROM AUTHOR]

This study was intended to appraise the anti-inflammatory and anti-arthritic potential of Chrysin (CR), a natural dietary flavone found in several plant genera, including Passiflora and Propalis, and honey. The in vitro anti-arthritic potential was assessed by protein denaturation and membrane stabilization assays. The acute anti-inflammatory action was assessed by Carrageenan and Xylene induced oedema models in Wistar rats. For determining anti-arthritic potential, 0.1 ml Complete Freund's adjuvant was injected into the left hind paw of rats to induce adjuvant-induced arthritis, followed by initiation of treatment with individual CR at 25, 50, 100 mg/kg and in combination with methotrexate (MTX) by oral gavage for 21 days. The standard treatment group was given MTX (1 mg/kg). Treatment with MTX, chrysin and their combination exhibited a notable inhibition of paw oedema and pain, restoration of body weight and immune organ weight as evident by the histology of ankle joints. Treatment with chrysin alone and in combination significantly (p < 0.0001) restored altered blood parameters (CRP, RF, Hb, WBC, and platelets) with notable (p < 0.0001) down-regulation of interleukin (IL)-6,-1β, tumor necrosis factor-α, NF-κβ, and cyclooxygenase-2 and up-regulation (p < 0.0001) of IL-4, 10, and I-κβ in contrast to disease control rats. The treatment with the combination noticeably improved the superoxide dismutase, and catalase activities while reduced the peroxidation level in liver homogenate. It can be concluded from the findings that chrysin especially in combination with MTX ameliorated CFA-induced arthritis owing to its profound anti-oxidant, analgesic and anti-inflammatory actions. [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]

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]

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]

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 structural change of receptor protein at high temperatures is one of the factors affecting the targeting ability of ligand‐installed nanocarriers for combined therapy of hyperthermia and drug delivery. In this study, the binding behaviors and mechanisms of integrin αvβ3 receptor and the arginine‐glycine‐aspartic acid (RGD) peptide ligand at high temperatures were investigated both theoretically and experimentally. The structural parameters of integrin αvβ3 at different temperatures and the interaction forces between the RGD peptide and integrin αvβ3 at different binding sites were calculated by molecular dynamics simulation. Fourier transform infrared spectroscopy, energy dispersive spectroscopy, ultraviolet–visible absorption spectroscopy, and atomic force microscopy were used to analyze the structural changes of integrin αvβ3 and to measure the ligand‐receptor interaction. Results show that the number of hydrogen bonds decreased and the secondary structure of integrin αvβ3 changed with the increase in temperature, indicating the denaturation of integrin αvβ3. The structural stability of the integrin αv subunit was better than that of the integrin β3 subunit at high temperatures. The interaction between the RGD peptide and integrin αvβ3 weakened as the temperature increased because the structure of the integrin αvβ3 binding site became more flexible and the corresponding calcium ions were shed from the binding site. The strongest interaction force was exhibited at the binding site of the integrin β3 subunit at 310 K while it was found at the binding site of the integrin αv subunit at higher temperatures, owing to the smaller structure deformation of the integrin αv subunit. [ABSTRACT FROM AUTHOR]

• Importance of initial freezing rate on meat quality during frozen storage was noted. • Initial quick freezing reduced quality losses during frozen storage of meat. • Protein denaturation and water migration were inhibited by quick freezing. This study aimed to address the effects of initial freezing rate on quality change, myofibrillar protein denaturation and water status evolution of beef muscles during subsequent frozen storage (0, 7, 30, 60, 90 and 180 d). Beef steaks were allocated to different freezing methods, including -80/-18 °C (frozen at -80 °C for 7 d and then stored at -18 °C until the end of duration), -80/-12 °C (frozen at -80 °C and then stored at -12 °C), -18 °C (frozen and stored at -18 °C) and -12 °C (frozen and stored at -12 °C). Results showed a rising degree of quality deterioration, myofibrillar protein denaturation and water migration with extended storage duration, wherein significant impacts were observed by the initial freezing rate. Samples subjected to -80/-12 °C treatment exhibited significantly lower (P < 0.05) thaw loss, cook loss, shear force value and colour difference coefficient ΔE than those in samples of group -12 °C. Similar results were observed between -80/-18 °C and -18 °C groups. Besides, initial quick freezing samples exhibited less severe protein denaturation (higher solubility, total sulfhydryl content and lower surface hydrophobicity), reduced water mobility (lower T 2 relaxation times) as well as relatively compact ultrastructure of muscle. Noteworthily, no tangible differences were found in the quality attributes between beef samples subjected to -18 °C and -80/-12 °C throughout frozen storage (P > 0.05). [ABSTRACT FROM AUTHOR]

Fouling deposition in the coconut cream emulsion (CCE) is considered a severe technical issue in the industry. Since the fouling deposition results from the heating effect on the CCE bulk, the heat‐induced structural changes in the CCE bulk at different temperatures were rheologically investigated in the first part of this study. The second part applied different heat treatment conditions to investigate generated fouling deposition (GFD). Chemical composition, FTIR, and SEM imaging were used to explore GFDs thoroughly. The increase in viscosity and storage modulus (G′) reflect such heat‐induced changes over the experimental conditions. More structural changes were predicted at around ≥85°C, accompanied by a sharp increase in viscosity and (G′), which was associated with the gelation of CCE. The conformational transition, fat agglomeration in CCE bulk, generated fouling deposits (GFDs) were significant around 70°C. The chemical composition of the GFD has shown an increasing trend in the protein, carbohydrates, and ash, meanwhile fluctuation in the fat contents with increasing temperature. The FTIR peaks showed novel peaks around temperature ≥85°C, which implied new amide groups or new protein conformation. The SEM images provided the different microstructures of GFDs at high‐temperature levels. More likely the GFDs appeared at temperature ≥85°C are a gel deposit layer. These findings strongly suggest that emulsion gelation was the primary cause of coconut cream fouling. [ABSTRACT FROM AUTHOR]

Quaternary cationic surfactants with bactericidal activity such as Didecyldimethylammonium chloride (DDAC) show an inactivation effect on enveloped viruses, but they have little effect on non-enveloped viruses such as noroviruses. Therefore, we examined additives that enhance the inactivation effect of cationic surfactants by using Feline calicivirus (FCV) as a representative of a non-enveloped virus. The result was that SO42- ions, which are a general-purpose salt, had a strong salting-out effect that reduced the solubility of proteins, greatly enhancing the inactivation ability of DDAC. The SO42- ions also enhanced FCV inactivation by other cationic surfactants such as Cetylpyridinium Chloride (CPC) and Benzalkonium chloride (ADBAC). To clarify the mechanism, we evaluated the denaturation and binding process of DDAC to Bovine Serum Albumin (BSA) as a model protein by means of Circular Dichroism (CD) spectrum and Isothermal Titration Calorimeter (ITC), respectively. The SO42- ions disturbed the protein structure by their salting- out effect and promoted cooperative binding from lower DDAC concentrations by reducing the Critical Micelle Concentration (CMC), indicating that these synergistic effects caused a large structural change in the protein. These results suggested that increasing the protein denaturation of the cationic surfactants by adding SO42- ions enhanced the inactivation effect on the non-enveloped virus. [ABSTRACT FROM AUTHOR]

• 1,2,4-Triazolium Ionic Liquids are synthesized and characterized. • The solvent nature of the ionic liquids is evaluated through photophysical studies. • The effective intercalation of ionic liquids with beta cyclodextrin is observed. • The ionic liquids are found to be capable in stabilizing serum albumin in their native state. • The alkyl chain of ionic liquid plays a prominent role in their association with organized media. Room temperature ionic liquids (RTILs) are utilized as solvents and catalysts in organic reactions, with applications spanning from electrochemistry to the detergent sector. Researchers extensively study imidazolium ILs for photophysical analysis in many applications. There are limited studies on the synthesis of triazolium-based ILs and their subsequent photophysical characterization. 1-Alkyl-1,2,4-triazolium-based ILs are selected for their adjustable physiochemical characteristics, strong stability, and capacity for recovery and multiple uses. Two ILs were developed in this study: 1-pentyl-1,2,4-triazolium trifluoroacetate (1-pent3HTTFA) and 1-hexyl-1,2,4-triazolium trifluoroacetate (1-hex3HTTFA). We evaluated the solvent properties of the synthesized ILs using coumarin as a fluorescent probe. Additionally, we investigated the microemulsification of the ILs by using β-Cyclodextrin as the heterogeneous medium. Experiments were conducted to investigate how two triazolium-based ILs interacted with bovine serum albumin (BSA) and their ability to prevent protein denaturation. [ABSTRACT FROM AUTHOR]

In view of the merits of all-purpose wheat flour (APWF) to soft wheat flour (SWF) in cost and protein supply, the feasibility of heat-moisture treatment (HMT, 19% moisture for 1 h at 60, 80 and 100 °C, respectively) to modify APWF as a substitute SWF in making short dough biscuits was explored. For underlying mechanisms, on the one hand, HMT reduced the hydration capacity of damaged starch particles by coating them with denatured proteins. On the other hand, HMT at 80 °C and 100 °C significantly denatured gluten proteins to form protein aggregates, highly weakening the gluten network in dough. These two aspects jointly conferred APWF dough with higher deformability and therefore significantly improved the qualities of biscuits. Moreover, the qualities of biscuits from APWF upon HMT-100 °C were largely comparable to that from SWF, even higher values were concluded in spread ratio, volume, specific volume and consumer acceptance. [Display omitted] • Heat-moisture treatment (HMT) modified all-purpose flour for short dough biscuit. • HMT reduced the hydration capacities of flour components, especially that of damaged starch. • HMT weakened starch-starch, protein-starch and protein-protein interactions in dough. • All-purpose flour by HMT-100 °C presented comparable biscuit quality to soft wheat flour. [ABSTRACT FROM AUTHOR]

Muscle protein stability during freeze-thaw (F-T) cycles was investigated with tilapia cultured in recirculating aquaculture systems (RAS) and traditional aquaculture in ponds (TAP). This study found that fatty acids (eg., palmitic acid) were enriched in TAP, while antioxidants (eg., glutathione) were enriched in RAS. Generally, proteins in the RAS group exhibited greater stability against denaturation during the F-T cycle, suggested by a less decrease in haem protein content (77% in RAS and 86% in TAP) and a less increase in surface hydrophobicity of sarcoplasmic protein (63% in RAS and 101% in TAP). There was no significant difference in oxidative stability of myofibrillar protein between the two groups. This study provides a theoretical guide for the quality control of tilapia cultured in RAS during frozen storage. [Display omitted] • Muscle composition of tilapia from different aquaculture system was analyzed. • Metabolomics suggested an enrichment of antioxidants in RAS fish muscle. • Proteins in RAS group had greater stability during the freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

This study confronts challenges from global population growth, focusing on protein supply strains and the environmental impact of traditional animal sources. Delving into unexplored territory, this study investigates the combined effects of pH, concentration, and temperature on the rheological and thermal properties of cowpea protein concentrate (CPC). Steady-state and oscillatory rheological tests, along with differential scanning calorimetric analysis, were conducted to unveil the behavior of CPC solutions. The results revealed sensitivity to protein concentration and shear rate, especially at higher concentrations (>10%), and pH emerged as a critical factor, significantly influencing shear stress and viscosity. The elastic and viscous components of alkaline CPC solutions exhibit weak gel behavior, influenced by both pH and frequency. Temperature-induced changes in viscosity and gelation highlight the interaction between thermal conditions and protein structures. The thermal cycle helps explain changes in molecular interactions induced by temperature, with pH playing a role in influencing gelatinization and denaturation. The denaturation temperature (T d) in the thermograms corresponds to vicilin fractions and emphasizes the prominence of denaturation and gelation at neutral pH, where T d was pH 7 > pH 9 > pH 11. Alkaline pH induced significant structural changes, resulting in a gelation onset temperature below the denaturation onset temperature. This study provides a deeper understanding into the rheological and thermal properties of CPC solutions, emphasizing the roles of concentration, pH, and temperature, useful for various steps of industrial processing, before and after thermal gelation. These findings are important for promoting the use of cowpea proteins in the food industry in response to the evolving needs of a growing global population. [Display omitted] • pH plays a critical role, affecting shear stress, viscosity and elastic behavior. • Protein structure and molecular interaction change viscosity during thermal cycle. • Protein gelation begins before the thermal denaturation onset at alkaline pH. • Alkaline pH induces structural changes that affect gelation and denaturation onsets. • Guidance for the use of cowpea protein concentrates in the industrial sectors. [ABSTRACT FROM AUTHOR]

The cooking of pulses causes gelatinization−melting of starch and denaturation of proteins. These thermal transitions were studied in beans and chickpeas using differential scanning calorimetry (20−160 °C, water contents ranging from 0.2 to 4.0 kg kg−1 dry basis). In the thermogram, the shape and temperature of the transition peaks depended on the water content in starch and protein. The thermogram was analyzed to quantify water distribution between starch and protein, assuming the coexistence of two water populations. After modeling the peaks as Gaussian functions, the distribution of water during heating was modeled as a Weibull distribution with water dependent parameters. Most water was available in protein, and was reallocated from protein to starch during heating. The fraction of water attributed to starch increased from less than 10 % of total water to 35−45 % at the end of cooking. Competition between starch and protein for available water delayed all thermal transitions. • Starch transitions occurs at higher temperatures when mixed with proteins. • Water distribution differs between starch and protein. • In starch−protein mixtures, the protein phase captures the most water. • Water reallocates from protein to starch during heating. • The transitions of starch determine the temperature range of water redistribution. [ABSTRACT FROM AUTHOR]

• CU-IRD displayed marked enhancements in heat and moisture transport efficiency. • CU and IR increased myosin denaturation and water fluidity. • CU destroyed the fiber integrity and improved the texture. • CU-IRD showed the shortest drying time and higher drying uniformity. 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 T 2 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%. [ABSTRACT FROM AUTHOR]

The functional structure of proteins results from marginally stable folded conformations. Reversible unfolding, irreversible denaturation, and deterioration can be caused by chemical and physical agents due to changes in the physicochemical conditions of pH, ionic strength, temperature, pressure, and electric field or due to the presence of a cosolvent that perturbs the delicate balance between stabilizing and destabilizing interactions and eventually induces chemical modifications. For most proteins, denaturation is a complex process involving transient intermediates in several reversible and eventually irreversible steps. Knowledge of protein stability and denaturation processes is mandatory for the development of enzymes as industrial catalysts, biopharmaceuticals, analytical and medical bioreagents, and safe industrial food. Electrophoresis techniques operating under extreme conditions are convenient tools for analyzing unfolding transitions, trapping transient intermediates, and gaining insight into the mechanisms of denaturation processes. Moreover, quantitative analysis of electrophoretic mobility transition curves allows the estimation of the conformational stability of proteins. These approaches include polyacrylamide gel electrophoresis and capillary zone electrophoresis under cold, heat, and hydrostatic pressure and in the presence of non-ionic denaturing agents or stabilizers such as polyols and heavy water. Lastly, after exposure to extremes of physical conditions, electrophoresis under standard conditions provides information on irreversible processes, slow conformational drifts, and slow renaturation processes. The impressive developments of enzyme technology with multiple applications in fine chemistry, biopharmaceutics, and nanomedicine prompted us to revisit the potentialities of these electrophoretic approaches. This feature review is illustrated with published and unpublished results obtained by the authors on cholinesterases and paraoxonase, two physiologically and toxicologically important enzymes. [ABSTRACT FROM AUTHOR]

Summary: The mechanism of protein denaturation of frozen surimi enriched with soluble soybean polysaccharides (SSPS) was investigated. Near‐infrared (NIR) and hyperspectral imaging (HSI) technology were used to predict protein denaturation. The fresh grass carp surimi was divided into four groups with SSPS additions of 0%, 1%, 3% and 5%, respectively, which were frozen and stored at −18 °C. Samples were examined after 0, 1, 2, 4 and 8 weeks, for salt‐soluble protein content, total SH, NIR hyperspectral image and Raman spectrum features. The results showed that addition of SSPS decelerated protein degradation. After 8 weeks of storage, the 5% SSPS addition maintained the highest salt‐soluble protein content, while for total SH, 3% and 5% SSPS addition had similar effect. Raman spectra illustrated that SSPS had the ability of maintaining an α‐helix content, as well as decreasing the exposure of polar groups, and reducing the oxidation of SH group into disulphide bonds. NIR spectra showed that the overall reflectance of frozen surimi increased with the increase in SSPS. Two partial least squares regression (PLSR) models were established after pretreatment of HSI spectral statistics and selection of characteristic wavelengths. The distribution maps were finally generated based on the simplified PLSR models. [ABSTRACT FROM AUTHOR]

Surimi is a protein concentrate formed basically by fish myofibrillar proteins. For better quality conservation, natural or synthetic cryoprotectants, with emphasis on sucrose, sorbitol and/or sodium tripolyphosphate are added to surimi. Studies show that it is possible to replace these synthetic additives and offer a final product with healthier properties to the consumer. This review highlights the importance of reducing the use of synthetic additives in the conservation of surimi and suggests potential natural alternatives for the total or partial replacement of these artificial substances, as well as discussing the effects of different types of natural compounds on the quality characteristics of surimi gel. [ABSTRACT FROM AUTHOR]

Almonds (Prunus dulcis) seeds, from the Rosaceae family, have been reported to contain essential nutrients that reduced inflammation by lowering certain inflammatory markers. This study evaluated the anti-inflammatory activity of P. dulcis (Almond seed) extract and fractions (n-hexane and aqueous). Dried almond seed (700 g) was pulverized and soaked in distilled water for 24 hrs. The aqueous extract was filtered and the filtrate was lyophilized to obtain the seed aqueous crude extract. The crude extract portion was dissolved in water, partitioned with n-hexane and separately concentrated to dryness to obtain the aqueous and n-hexane fractions. Anti-inflammatory activity of almond seed extract and fractions were carried out via erythrocyte membrane stabilization, antitryptic and protein denaturation inhibitory assays. Results obtained shows that n-hexane fraction of P. dulcis seed stabilized stressed erythrocyte maximally (18.70 ± 3.23%) at 2.00 mg/mL and aqueous fraction (16.72 ± 1.97%) at 0.5 mg/mL, while aqueous extract highest % stability was 17.73± 2.32% at 2.00 mg/mL. Also, n-hexane fraction inhibited trypsin better at higher concentrations while the aqueous fraction was at a lower concentration. However, both showed better anti-tryptic activity than aqueous crude extract.Moreover, maximum percentage protein inhibitory activities for diclofenac (800 µg/ml), aqueous fraction (800 µg/ml), n-hexane fraction (1600 µg/ml) and aqueous extract (1600 µg/ml) were 72, 51, 35 and 32 respectively.This study concludes that almond seed fractions showed better anti-inflammatory activity compared to their crude extract. Therefore, the isolation of active compounds from these fractions may provide a novel antiinflammatory drug. [ABSTRACT FROM AUTHOR]

Passive microwave radiometry (MWR) is a measurement technique based on the detection of passive radiation in the microwave spectrum of different objects. When in equilibrium, this radiation is known to be proportional to the thermodynamic temperature of an emitting body. We hypothesize that living systems feature other mechanisms of emission that are based on protein unfolding and water rotational transitions. To understand the nature of these emissions, microwave radiometry was used in several in vitro experiments. In our study, we performed pilot measurements of microwave emissions from egg whites during denaturation induced by ethanol. Egg whites comprise 10% proteins, such as albumins, mucoproteins, and globulins. We observed a novel phenomenon: microwave emissions changed without a corresponding change in the water's thermodynamic temperature. We also found striking differences between microwave emissions and thermodynamic temperature kinetics. Therefore, we hypothesize that these two processes are unrelated, contrary to what was thought before. It is known that some pathologies such as stroke or brain trauma feature increased microwave emissions. We hypothesize that this phenomenon originates from protein denaturation and is not related to the thermodynamic temperature. As such, our findings could explain the reason for the increase in microwave emissions after trauma and post mortem for the first time. These findings could be used for the development of novel diagnostics methods. The MWR method is inexpensive and does not require fluorescent or radioactive labels. It can be used in different areas of basic and applied pharmaceutical research, including in kinetics studies in biomedicine. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to assess the effects of ultrasonic‐assisted immersion freezing (UIF) of 0, 15, 30 and 45 W L−1 on the conformation changes of pork myofibrillar protein (MP). The structure and conformation of MP were evaluated, and the solubility, thermal stability and sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) were also discussed. The sample treated with 30 W L−1 (UIF‐30) had the highest total protein solubility (116.6 mg g−1) and thermal denaturation temperature (57.07℃) compared with other treatments. UIF‐30 has higher α‐helix content, and fluorescence intensity together with surface hydrophobicity had insignificant changes compared with the control. In SDS–PAGE, only the sample treated with 45 W L−1 (UIF‐45) showed slight band degradation. In general, UIF‐30 effectively minimised the changes of protein conformation, which may be related to the reduction of mechanical damage to muscle cells caused by rapid freezing to form regular and uniform ice crystals. This is more conducive to reducing pork quality degradation caused by protein freeze denaturation. [ABSTRACT FROM AUTHOR]

The quality of meat in prepared dishes deteriorates due to excessive protein denaturation resulting from precooking, freezing, and recooking. This study aimed to link the precooked state with chicken breast's recooked quality. Cooked Value (CV), based on protein denaturation kinetics, was established to indicate the doneness of meat during pre-heating. The effects of CV s after pre-heating on recooked qualities were investigated compared to fully pre-heated samples (control). Mild pre-heating reduced water migration and loss. While full pre-heating inhibited protein oxidation during freezing, intense oxidation during pre-heating led to higher oxidation levels. Surface hydrophobicity analysis revealed that mild pre-heating suppressed aggregation during recooking. These factors contributed to a better texture and microstructure of prepared meat with mild pre-heating. Finally, a potential mechanism of how pre-heating affects final qualities was depicted. This study underlines the need for finely controlling the industrial precooking process to regulate the quality of prepared meat. • Mild pre-heating enhanced final qualities of prepared chicken breasts. • A scale of cooked value for pre-heating degree was established. • Mild pre-heating reduced water loss and enhanced water holding capacity. • Mild pre-heating prevented excessive protein oxidation. • Mild pre-heating decreased protein aggregation during re-cooking. [ABSTRACT FROM AUTHOR]

The quality of surimi, widely used in processed seafood, is compromised by freeze–thaw cycles, leading to protein denaturation and oxidative degradation. The objective of this study is to explore the effects of adding natural whey peptide hydrolysate (WPH) on the myofibrillar proteins of repeatedly freeze–thawed surimi. Results indicated surimi treated with 15% WPH exhibited only a 128% increase in surface hydrophobicity and a maximum peroxide value of 7.84 μg/kg, significantly lower than the control group. Additionally, salt-soluble protein content, emulsification activity, and stability decreased with the increase in freeze–thaw cycles. With a 15% WPH offering the most significant protective effect, evidenced by reductions of only 25.02%, 42.52% and 37.02% in salt-soluble protein content, emulsification activity, and stability, respectively. These outcomes demonstrate that WPH effectively reduces protein denaturation during repeated freeze–thaw processes. Future research should explore the molecular mechanisms underlying WPH's protective effects and evaluate their applicability in other food systems. [Display omitted] • Surimi with 15% whey protein hydrolysate showed significantly lower peroxide values • 15% whey protein hydrolysate improves the water holding capacity of surimi • 15% whey protein hydrolysate increases protein ATPase activity • 15% whey protein hydrolysate facilitates maintenance of protein spatial conformation • Whey protein hydrolysate act as a natural alternative to antifreeze [ABSTRACT FROM AUTHOR]

The muscle structure and composition may vary along the different portions of fish fillets, which can complicate the quality and storage stability of products. Loins and tails from Atlantic cod (Gadus morhua) and redfish (Sebastes marinus) fillets were therefore stored at −25 °C up to 16 months and 20 months, respectively, to investigate the quality changes influenced by the duration of frozen storage within the fillet portions. Throughout the storage period, the loss of total sulfhydryl groups correlated with increased disulfide bonds, indicating partial oxidative protein degradation. This may be linked with protein denaturation as evidenced by the decrease of soluble proteins, as well as decreased water holding capacity and increased thawing drip loss and cooking loss. The results from the cod samples reveal that stronger degradation changes occurred in the tail. The loin, therefore, had more storage stability as well as higher nutritional value. However, other quality attributes were similar between the two portions in the redfish fillets. Higher free fatty acid (FFA) values, lower soluble protein contents, and higher disulfide bond contents were obtained in the cod samples compared to the redfish samples at the same storage time, indicating that lipid hydrolysis and protein degradation effects were stronger in the cod (lean fish) compared to redfish (medium fat species). • Partial protein degradation occurs during the frozen storage of cod and redfish. • Protein degradation is associated with loss of water retention properties. • Cod loins have higher nutritional value and slower degradation than the tail. • Quality attributes and stability are similar between the loins and tails of the redfish. • Cod shows stronger protein degradation during frozen storage compared to redfish. [ABSTRACT FROM AUTHOR]

Chemical chaperones are low-molecular compounds counteracting protein aggregation. Understanding of the mechanism of their effects is key to their potential use in biotechnology. The aggregation of bovine liver glutamate dehydrogenase (GDH) was studied at 40 °C and 50 °C using dynamic light scattering, analytical ultracentrifugation, size-exclusion chromatography and differential scanning calorimetry. At 40 °C the GDH aggregation proceeds through the slow stages of hexamer dissociation and formation of small oligomeric aggregates. At 50 °C these stages are transient. The rate-limiting stage of the overall aggregation process is unfolding of the protein molecule; the order of aggregation with respect to protein, n = 1. The test system based on GDH aggregation at 50 °C was used to quantify the anti-aggregation activity of chemical chaperones by comparing their half-saturation concentrations [L] 0.5. Arginine ethyl ester had the highest anti-aggregation activity, with [L] 0.5 = 4 ± 1 mM. For other additives, [L] 0.5 was 22 ± 1 mM (arginine), 18 ± 1 mM (argininamide) and 95 ± 12 mM (proline). Arginine at concentrations up to 300 mM, argininamide at concentrations higher than 300 mM and arginine ethyl ester at concentrations higher than 500 mM enhance aggregate-aggregate sticking. These results explain the mechanism of heat-induced GDH aggregation and its peculiarities at different temperatures or in the presence of chemical chaperones. • Glutamate dehydrogenase (GDH) aggregates via irreversible dissociation and oligomerization. • The rate-limiting stage is unfolding of the protein molecule. • All the additives studied stabilize native GDH, its dissociated forms and small aggregates. • Arginine ethyl ester had the highest anti-aggregation activity, [L] 0.5 = 4 ± 1 mM. [ABSTRACT FROM AUTHOR]

Background: Antioxidants are chemical substances, either synthetic or natural, that can avert or slow down a range of cellular damage. Objectives: The purpose of this study was to verify the antioxidant and anti-inflammatory properties of alcoholic and aqueous extracts of Ficus infectoria fruits. Materials and Methods: DPPH free radical quenching test, reducing power technique, and hydrogen peroxide scavenging tests were used to assess antioxidant efficacy. In vitro anti-inflammatory experiments were also investigated for membrane stabilization potential and inhibition of proteins from denaturation. Results: Fruits included alkaloids, steroids, phenolics, flavonoids, and amino acids, according to phytochemical study. The total phenolic and flavonoid content of the methanolic and aqueous preparations were determined to be 576.16 ± 129.10 and 416.12 ± 112.01 mg/g Gallic Acid Equivalents (GAE) and 423.17 ± 56.48 and 253.35 ± 24.07 mg/g Rutin Equivalents (RE) respectively. In comparison to the benchmarks Rutin and ascorbic acid, both preparations showed significant DPPH and H2O2 quenching efficacy. As compared to the standard Indomethacin, both preparations have strong membrane stabilising and protein denaturation inhibitory potencies Conclusion: The current findings point to Ficus infectoria's antioxidant and anti-inflammatory properties. However, the active ingredients relevant for the activity must be identified and purified, and the exact mechanism must be determined. [ABSTRACT FROM AUTHOR]

Introduction: Inflammation is body's immune response to harmful stimulus. Commonly used conventional antiinflammatory agents are Non-Steroidal Anti-inflammatory Drugs (NSAIDs). But on prolonged long-term use, it causes serious adverse events. So, the search towards natural agents which have anti-inflammatory property are increasing nowadays. Sinapis arvensis is an annual flowering plant which has proven multipurpose medicinal phytoconstituents. Aim: To evaluate in-vitro anti-inflammatory effects of flower extracts of Sinapis arvensis with diclofenac as standard. Materials and Methods: This in-vitro study assessed the laboratory based anti-inflammatory activity, performed using Bovine Serum Albumin (BSA) assay in December 2021 at Sree Balaji Medical College and Hospital, Chennai, Tamil Nadu, India. BSA at pH of 6.8 generated denatured proteins. The anti-inflammatory activity of the sample (flower extracts of Sinapis arvensis) and standard (Diclofenac) was assessed by adding to BSA and percentage of inhibition of denaturation were calculated using the formula based on the absorbance measured. Descriptive statistics was used for analysis of collected data. Results: The concentration-dependent inhibition of protein denaturation was observed for both Sinapis arvensis and Diclofenac. At 100 µg concentration, percentage of inhibition reached up to 81.8% and 100% for Sinapis arvensis and Diclofenac, respectively. Conclusion: The present study showed that flower extracts of Sinapis arvensis exhibited concentration dependent antiinflammatory property invitro which proves to be nearly equivalent with that of the standard Diclofenac. [ABSTRACT FROM AUTHOR]

Unalike parts of Crocus sativus plant have revealed important biological activities. In folklore petals and roots of crocus sativus plant, are used to treat various diseases like diarrhea, Gastritis, cold, bronchitis, cough, Diabetes, and Infections. The present study was designed to explore in vitro anti-inflammatory potential of Crocus Sativus stigmas. Crocus Sativus has been used conventionally for different inflammatory disorders. A few results about in vitro antiinflammatory activity of extract fractions have been published until now. Hence, aim of this study was to evaluate in vitro anti-inflammatory potential of Crocus Sativus ethanolic extract methanolic and petroleum benzine fraction. Serial dissolutions were prepared at 125, 250 and 500µg/mL from each extract fraction of crocus sativus stigmas, which were used to evaluate anti-inflammatory activity in vitro by protein denaturation method, using Aspirin as standard drug. Both extract fractions were able to exhibit major anti-inflammatory activity. However, methanolic extract fraction revealed the highest percentage inhibition, suggesting major concentration of compounds with promising anti-inflammatory effect. So with these findings results can be concluded that crocus sativus stigmas possess in vitro anti-inflammatory properties at different concentrations Percent inhibition of protein denaturation of these extract fractions was within the range of 33.0-59.25%, for petroleum benzine fraction and for methanolic fraction 46.94 to 63.74 and exhibited a significantly higher (p < 0.001) inhibition level. [ABSTRACT FROM AUTHOR]

Hibiscus is a genus of a gorgeous flowering potted plant. Hibisceae tribe is one of the ornamental plants that are most commonly available and it belonging to Malvaceae family is Hibiscus rosa-sinensis. The purpose of this work is to evaluate the in-vitro anti-athritic effect of Hibiscus rosa sinensis at various levels of concentration. Here the percentage of membrane stabilization was carried out at various concentrations for ethanolic extract and Diclofenac sodium. Hibiscus extract was found to have maximum membrane stabilization of 94.97% at 500µg/ml. The highest percentage inhibition of denaturation of protein and membrane stabilization for these plant extracts were found to be 89.45% and 91.09% at a dose of 500µg/ml. Our research studies support the isolation and the use of active phytochemicals of hibiscus in the treatment of inflammation and arthritis. [ABSTRACT FROM AUTHOR]

• The bark extracts of Terminalia catappa are effective in reducing the hind paw of rats of carrageenan-induced paw edema during the second phase of the inflammation by inhibiting prostaglandins – mediated inflammatory pathway. • The bark extracts have the potential to act as an anti-inflammatory agent by inhibiting myeloperoxidase mediated tissue damage. • Adjuvant-induced arthritis in rats causes bone destruction by increasing bone resorption and reducing bone formation. • Bark extracts treatment reduced secondary lesions developed by adjuvant-induced arthritis by suppressing the cell-mediated immunity. Terminalia catappa Linn (T. catappa) belongs to the family Combretaceae, locally known as Bengal Almond. The plant is known to have many phytochemicals such as carbohydrates, phytosterols, tannins, polyphenols, flavonoids, and saponins. It is widely used in the treatment of various diseases such as dermatitis, leprosy, and scabies and internally for colic, headache and hepatitis and also, the plant possesses anticancer, antioxidant, antidiabetic, hepatoprotective and extracts have been shown to modify reproductive behavior in rats. The main objective of this study is to assess the pharmacological potentials of T. catappa bark in the therapeutic areas of inflammation and arthritis. T. catappa bark alcoholic extract (TCE) and water extract (TCW) were prepared and evaluated for its possible anti-inflammatory activity by in vitro protein denaturation assays and membrane stabilization assay. Further, the anti-inflammatory and anti-arthritic activity of bark extracts were evaluated by in vivo models such as carrageenan-induced paw edema, air-pouch model and Complete Freund's adjuvant (CFA) induced arthritis model in rats. Total phenolic content (TPC) was found to be 287 and 175 mg/g for TCE and TCW. Total flavonoid content (TFC) was found to be 10.2 and 61.7 mg/Kg for TCE and TCW. The concentration required for the 50 % inhibition of the protein denaturation (IC 50) was found to be lower for TCE (36.2 µg/mL) in egg albumin denaturation assay, whereas in the membrane stabilization assay method TCW exhibited a lower IC 50 value in comparison with diclofenac. Both the extracts showed activity in the in vitro models of inflammation and were also found to be effective in reducing the paw edema in the carrageenan-induced inflammation model and inhibition of cellular infiltration and Myeloperoxidase activity in air pouch fluid, suggesting its anti-inflammatory activity. In CFA-induced arthritis model, the extracts exhibited anti-arthritic potential by improving the altered blood parameters, arthritic scores, radio-graphical, and histopathological changes. The results of the study suggested that the bark of T. catappa possessed anti-inflammatory and anti-arthritic activities. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to investigate the influence of different wet heating methods (SC: steam cooking; BC: boiling cooking) on the water distribution, microstructure and protein denaturation of pork steaks. Results showed that SC increased the proton relaxation intensity (T1 and T2) and the amount of immobilized water, but decreased the amount of free water compared with BC treatment. Proton density images showed that the red area was more in SC treatment than BC treatment. Muscle volume contraction and microstructure destruction in SC treatments were lower than that of BC treatments. Meanwhile, SC had higher protein solubility, but lower surface hydrophobicity as compared with BC. Additionally, pork steaks containing salt cooked by the same heating method had higher water mobility than those of without salt. Moreover, salting process aggravated the swelling of muscle fibre structure and protein denaturation. [ABSTRACT FROM AUTHOR]