Protein Isolate Research Articles

Covalent Attachment of Functional Proteins to Microfiber Surfaces via a General Strategy for Site-Selective Tetrazine Ligation.

Surface modification of materials with proteins has various biological applications, and hence the methodology for surface modification needs to accommodate a wide range of proteins that differ in structure, size, and function. Presented here is a methodology that uses the Affinity Bioorthogonal Chemistry (ABC) tag, 3-(2-pyridyl)-6-methyltetrazine (PyTz), for the site-selective modification and purification of proteins and subsequent attachment of the protein to trans-cyclooctene (TCO)-functionalized hydrogel microfibers. This method of surface modification is shown to maintain the functionality of the protein after conjugation with proteins of varying size and functionalities, namely, HaloTag, NanoLuc luciferase (NanoLuc), and fibronectin type III domains 9-10 (FNIII 9-10). The method also supports surface modification with multiple proteins, which is shown by the simultaneous conjugation of HaloTag and NanoLuc on the microfiber surface. The ability to control the relative concentrations of multiple proteins presented on the surface is shown with the use of HaloTag and superfolder GFP (sfGFP). This application of the ABC-tagging methodology expands on existing surface modification methods and provides flexibility in the site-selective protein conjugation methods used along with the rapid kinetics of tetrazine ligation.

Conformational and processing properties of a high-active ingredient involving soy protein isolates bound with anthocyanins and its application in cake baking

Soybean protein is of plant origin and is commonly appropriate for improving the processing characteristics of foods. This study aimed to explore a novel functional ingredient that contained soybean protein isolate (SPI) and blueberry anthocyanins (BANs). The spatial conformation and secondary structure of SPI-BANs complexes were analyzed using circular dichroism and fluorescence spectroscopy, the processing properties were investigated as well as the retention of antioxidant activity during thermal treatments. Results showed that the contents of free sulfhydryl and free amino groups in complexes increased to 3.50 and 1.19 folds than those of SPI, respectively, while the surface hydrophobicity decreased by 74.23%. Compared with SPI, the BANs-modified SPI had a smaller particle size of 29.12 nm and a lower zeta-potential of -8.73 mV and on the other hand, the complexes possessed higher solubility (83.08%) and foaming and emulsifying properties (115.08% and 54.03 m2/g). After fortification with SPI-BANs, the baking loss rate and adhesiveness of chiffon cake were reduced by 10.82% and improved to 0.24 N.mm, respectively. The high antioxidant activities of SPI-BANs under heat led to the cake’s bioactivities largely enhanced by 1.99 ~ 12.71 folds, being 345.19 µg Trolox/g for the DPPH radical scavenging activity. This study developed the functional food ingredients as antioxidants and a substitute for animal-based proteins in bakery products, which was safe and sustainable by using the dietary components from plant resources.Graphical

How ultrasonication treatment drives the interplay between lysinoalanine inhibition and conformational performances: A case study on alkali-extracted rice residue protein isolate.

Lysinoalanine (LAL) formed during alkaline extraction of rice residue protein (RRPI), which limited its application in the food industry. In this study, the influence of ultrasonication parameters (acoustic power density, ultrasound duration, and ultrasound temperature) on the inhibition of LAL formation and conformational attributes of RRPI during alkaline extraction was elucidated. The results suggested that the acoustic power density substantially modified the chemical interaction forces between RRPI molecules. At a power density of 60W/L, the ionic bonds (14.37%) and hydrophobic interactions (49.28%) reached the maximum, while hydrogen bonds (15.29%) and disulfide bonds (21.06%) reached the minimum. Moreover, acoustic power density at 60W/L caused a decrease of 18.02% and 12.2% in α-helix, and β-turn, respectively, shifting toward β-sheet, random coil, with an increase of 7.31% and 36.16%. Following ultrasonication, the protein particle size distribution curve shifted in the direction of smaller particle size, forming a relatively concentrated and uniform protein distribution. Sonication power, temperature, and time decreased the absolute value of Zeta potential. Furthermore, significant destruction in microstructure was elicited by sonication, which made the structure looser and more microparticles. Pearson correlation analysis suggested that the inhibition in the levels of LAL was most influenced by the increase of sulfhydryl groups and Zeta potential, as well as the reduction of α-helix content, in which the alteration of the total sulfhydryl group content had a great impact on the Zeta potential and the free sulfhydryl group. The principal component analysis demonstrated a notable correlation between the total sulfhydryl group and both the Zeta potential and free sulfhydryl group of RRPI.

Effect of Processing Methods on Amino Acid and Fatty Acid Composition of Parkia biglobosa Seeds

Parkia biglobosa (PB) is among the various underexploited nutritious plants. A comparative study was conducted on the effect processing PB has on the amino and fatty acid composition. Fermented (FPB), defatted (DPB), and protein isolates (PI) samples were prepared from Parkia biglobosa seeds using various processing methods, and evaluated using standard analytical protocols. The PI showed the highest significant total non-essential amino acids, essential amino acids, and conditionally essential amino acids when compared with FPB and DPB. In addition, the PI showed the highest significant (p < 0.05) total neutral amino acids, basic amino acids, total aromatic amino acids, and the lowest percentage cystine ratio of total sulphur amino acids and total amino acids in comparison with FPB and DPB. The PI also showed a better-predicted protein efficient ratio, essential amino acid index, biological value, protein content, and nutritional index than FPB and DPB. Furthermore, PI amino acid composition was compared favourably with the reference scores for a whole hen’s egg, preschool child, and provisional scoring pattern. Arginine and histidine values of PI were higher than the recommended values. The FPB (42.29%) showed the highest polyunsaturated fatty acids compared with the DPB (41.94%) and PI (26.7%). The dominant saturated, monounsaturated, and polyunsaturated fatty acids were stearic acid (15.1 DPB), linoleic acid (42.29 DPB), and oleic acid (14.05 PI). The DPB (1.84) showed a better polyunsaturated to saturated (P:S) ratio than FPB (1.74) and PI (0.91). The results revealed that the processing methods improved the relative amino acid composition, whereas the fatty acid composition improved in DPB. Therefore, PI could serve as an alternative in the formulation of complementary foods.

Antimicrobial Activity of Diffusible Substances Produced by Lactococcus lactis Against Bacillus cereus in a Non-Contact Co-Culture Model

The symptoms of foodborne illness caused by Bacillus cereus often go unreported, complicating the effectiveness of conventional chemical and physical methods used to inhibit its growth in food production. This challenge, combined with the increasing use of lactic acid bacteria (LAB) in the food industry and consumer preference for minimally processed products, prompted this study. The antibacterial activity of diffusible substances produced by Lactococcus lactis ATCC 11454 against Bacillus cereus NC11143 and Escherichia coli K-12 MG1655 was investigated using a non-contact co-culture model utilising deMann Rogosa and Sharpe broth, with glucose as a carbon source. This study employed plate counting and flow cytometry to assess the impact of these substances on bacterial growth and to analyse their composition and antimicrobial efficacy. The co-culture of Lactococcus lactis ATCC 11454 resulted in the production of a stable antimicrobial peptide, which was heat resistant and acid tolerant. Purification was achieved via ammonium sulphate precipitation and preparative HPLC, yielding a peptide with a molecular mass of 3.3 kDa, with daughter ion fractions similar to nisin A. Antimicrobial activity studies demonstrated that the diffusible substances effectively inhibited B. cereus growth over a period of eight days and exhibited bactericidal activity, killing 99% of the B. cereus cells. Additionally, these substances also inhibited Escherichia coli K-12 MG1655 grown under similar conditions. Comparative analysis revealed that in the co-culture assay, L. lactis produced a 50% higher yield of the antimicrobial peptides compared to pure cultures. Similarly, the specific growth rate of L. lactis was four times higher. With respect to protein purification and concentration, ammonium sulphate precipitation coupled with solid phase extraction was most effective in the purification and concentration of the diffusible substances. The findings provide a basis for utilising bacteriocin-producing strains as a preservation method, offering an alternative to traditional chemical and physical control approaches especially for the food industry.

Structure and functionality of Pleurotus geesteranus protein isolate as a function of pH.

Edible mushroom proteins hold great potential for food applications, but those extracted using the alkaline extraction-acid precipitation method typically exhibit poor solubility in neutral water, with the structural changes during acid precipitation remaining unclear. In this study, Pleurotus geesteranus protein isolate (PGPI) with high water solubility was prepared with alkaline extraction, followed by dialysis and freeze-drying, and the effects of pH on the structural and functional properties of PGPI were systematically investigated. PGPI was enriched in essential and aromatic amino acids, and the molecular weight of bands in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile was mainly distributed below 45kDa. The zeta potential of PGPI changed from +16.84 to 17.58mV when the pH increased from 2 to 9, with a pI of 4.3. At pH 7, PGPI showed a size of 232.7nm. Away from pH 7, the particle size of PGPI increased. When the pH decreased from 7 to 2, PGPI exhibited a lower α-helix structure content and a higher β-sheet content and a gradual decrease in fluorescence intensity. In addition, as the pH approached 4, H0 and the content of SS group increased to a peak. These results indicated that lowering the pH induced the development of more ordered protein structure, which could be the primary reason for the poor water solubility of P. geesteranus protein obtained through alkaline extraction and acid precipitation. Additionally, these structural changes result in alterations to its functional properties, including water-holding capacity, oil-holding capacity, foaming capacity, foaming stability, emulsion activity index, and emulsion stability index.

Glycation of sunnhemp protein with dextran via dry heating: Thermal, micro-structural characterization, and amino acid profiling.

This study aims to obtain sunnhemp protein isolate (SHPI) and dextran conjugates by dry heating method of Maillard conjugation. The effects of different incubation time (0, 1, 3, 5, 7, and 9 days) on the molecular flexibility, available lysine content, antioxidant properties, molecular structure, and thermal and micro-structural properties of conjugates were compared with SHPI (no conjugation) at 60°C and 79% relative humidity. The results indicated the formation of SHPI-dextran conjugates as confirmed by the change in molecular flexibility, lysine content, antioxidant activities, color, and water activity values. The molecular structure revealed the confirmation of covalent bonding between SHPI and dextran. Differential scanning calorimetry and thermo-gravimetric analysis results exhibited improvement in the thermal stability of SHPI when conjugated with dextran. The microstructural characterization showed that Maillard conjugation changed the surface structure of SHPI. The analysis of amino acid composition displayed that lysine, arginine, and phenylalanine were the dominant Maillard reaction sites of SHPI and dextran. Among all the conjugated samples, 5 days of incubation time was selected as an optimum condition for the development of SHPI-dextran conjugates on the basis of the aforementioned characterization. Overall, it was concluded that Maillard conjugation of sunnhemp protein with dextran via dry-heating technique could modify and improve its various attributes. PRACTICAL APPLICATION: The conjugation of plant proteins with polysaccharide through the Maillard reaction under dry heating conditions represents a natural and green technique for improving the techno-functional properties of proteins. The study has the potential to establish framework for the utilization of Sunnhemp protein isolate-dextran conjugates. This approach offers the potential for cost-effective production of emulsifiers and development of effective encapsulating matrices. The investigation expands on an underutilized plant protein source facilitating an alternative to animal-based proteins and contributing to the development of a sustainable circular bioeconomy.

Exploring the Nexus Between Emulsifier Characteristics and Salmonella Typhimurium Viability in Oil‐in‐Water Emulsions

ABSTRACTMolecular characteristics of emulsifiers such as their molecular weight (MW) and surface charge, not only affect the stability of the emulsion but also can have an impact on its capacity to either inhibit or promote microbial proliferation. These characteristics can affect the behavior of pathogens such as Salmonella Typhimurium in emulsion systems. The growth and thermal resistance of S. Typhimurium were monitored at different oil content levels (20%, 40%, and 60%) in emulsions stabilized by three whey protein‐based emulsifiers: whey protein isolate (WPI), whey protein hydrolysate (WPH), and a modified WPI with an alteration of charge (WPI+). Our study revealed that emulsifier itself with different MW and surface charge had no effect on bacterial growth and inactivation without oil inclusion (p > 0.05). However, it was found that higher bacterial growth rate at 60% oil content emulsion stabilized with WPI+ (0.65 ± 0.03 log CFU/h) than WPI (0.19 ± 0.04 log CFU/h), which showed the charge of emulsifiers has different effects on microbial dynamics in oil‐in‐water emulsion. Interestingly, WPI+ in emulsions also seemed to convey protection against thermal inactivation of bacteria. These data describe a complex interrelationship between the physicochemical characteristics of the emulsifier and its interacting nature with bacterial cells. They throw even more light on the insight about the importance of a strategic approach toward emulsifier selection in food formulations. This is crucial for the food safety and stability of products.

Antibacterial and wound healing stimulant nanofibrous dressing consisting of soluplus and soy protein isolate loaded with mupirocin

Severe cutaneous injuries may not heal spontaneously and may necessitate the use of supplementary therapeutic methods. Electrospun nanofibers possess high porosity and specific surface area, which provide the necessary microenvironment for wound healing. Here in, the nanofibers of Soluplus-soy protein isolate (Sol-SPI) containing mupirocin (Mp) were fabricated via electrospinning for wound treatment. The fabricated nanofibers exhibited water absorption capacities of about 300.83 ± 29.72% and water vapor permeability values of about 821.8 ± 49.12 g/m2 day. The Sol/SPI/Mp nanofibers showed an in vitro degradability of 33.73 ± 3.55% after 5 days. The ultimate tensile strength, elastic modulus, and elongation of the Sol/SPI/Mp nanofibers were measured as 3.61 ± 0.29 MPa, 39.15 ± 5.08 MPa, and 59.11 ± 1.94%, respectively. Additionally, 85.90 ± 6.02% of Mp loaded in the nanofibers was released in 5 days in vitro, and by applying the Mp-loaded nanofibers, 93.06 ± 5.40% and 90.40 ± 5.66% of S. aureus and E. coli bacteria were killed, respectively. Human keratinocyte cells (HaCat) demonstrated notable biocompatibility with the prepared nanofibers. Furthermore, compare to other groups, Sol-SPI-Mp nanofibers caused the fastest re-epithelialization and wound healing in a rat model. The findings of this study present a novel nanofiber-based wound dressing that accelerates the healing of severe skin wounds with the risk of infection.

Pecan (Carya illinoinensis (Wangenh.) K. Koch) nuts as an emerging source of protein: extraction, physicochemical and functional properties.

The increasing demand for sustainable alternatives to traditional protein sources, driven by population growth, underscores the importance of protein in a healthy diet. Pecan (Carya illinoinensis (Wangenh.) K. Koch) nuts are currently underutilized as plant-based proteins but hold great potential in the food industry. However, there is insufficient information available on pecan protein, particularly its protein fractions. This study aimed to explore the physicochemical and functional properties of protein isolate and the main protein fraction glutelin extracted from pecan nuts. The results revealed that glutelin (820.67 ± 69.42 g kg-1) had a higher crude protein content compared to the protein isolate (618.43 ± 27.35 g kg-1), while both proteins exhibited amino acid profiles sufficient for adult requirements. The isoelectric points of protein isolate and glutelin were determined to be pH 4.0 and pH 5.0, respectively. The denaturation temperature of the protein isolate (90.23 °C) was higher than that of glutelin (87.43 °C), indicating a more organized and stable conformation. This is further supported by the fact that the protein isolate had a more stable main secondary structure than glutelin. Both proteins demonstrated improved solubility, emulsifying, and foaming properties at pH levels deviating from their isoelectric points in U-shaped curves. Compared to the protein isolate, glutelin displayed superior water and oil absorption capacity along with enhanced gelling ability. The protein isolate and glutelin from pecan nuts exhibited improved stability and competitive functional properties, respectively. The appropriate utilization of these two proteins will support their potential as natural ingredients in various food systems. © 2024 Society of Chemical Industry.

Study on solubility and solvation thermodynamics for the advancement of biorelevant activities of l-isoleucine and l-serine in aqueous ammonium chloride solutions in the temperature range of 288.15–308.15 K

This study investigated the dissolution behavior of l-isoleucine and l-serine in an aqueous salt solution (ammonium chloride), examining how variations in temperature and electrolyte concentration affect their solubility. We conducted careful experiments and used mathematical calculations to explore interactions at a molecular level. We observed that the structure of these amino acids and salt concentration in the aqueous medium influence their interactions, which affects dissolution. In the presence of electrolytes, l-isoleucine demonstrated a salting-out effect whereas l-serine showed a salting-in effect. This work examines the solute–solvent interactions of these solutes in aqueous ammonium chloride solutions. l-isoleucine exhibits a nonspontaneous reaction with increasing salt concentrations whereas l-serine shows spontaneous behavior. Gibbs free energy analysis revealed greater stability of l-serine. The pH and conductance measurements showed how these factors influence solution properties. This insight helps us comprehend the nature and behavior of these molecules in different situations, which could be helpful in drug formulation or protein purification in the future.

Identification of Plasma Protein Biomarkers for Predicting Lung Cancer.

Lung cancer remains a leading cause of cancer-related mortality worldwide, necessitating the development of effective early diagnostic strategies. Despite advancements in imaging and screening technologies, late-stage diagnoses remain common, limiting treatment options and reducing survival rates. Thus, there is a critical need for reliable, minimally invasive biomarkers to improve early detection and patient outcomes. Plasma protein biomarkers offer promising potential for early lung cancer detection and continuous disease monitoring. This study explored the potential of specific plasma protein markers as early indicators of lung cancer. Plasma samples were collected from normal healthy individuals and lung cancer patients, and protein purification and analysis were conducted using LC-MS/MS. A mixed-effect model was applied to select lung cancer-related protein markers based on label-free relative quantification values. We identified 29 proteins with potential for early lung cancer diagnosis, including complement proteins (CFB, C3, C8G, C1QA, C1R, C6), orosomucoid proteins (ORM1, ORM2), ceruloplasmin (CP), alpha-1-B glycoprotein (A1BG), and others. These proteins play diverse roles in immune response, inflammation, and cell signaling, suggesting their relevance in lung cancer pathophysiology. Our findings suggest the potential of plasma proteins as early diagnostic biomarkers for lung cancer. Further validation in larger cohorts is needed to confirm their clinical utility. Integrating these biomarkers into existing diagnostic modalities could enhance early detection accuracy, leading to improved patient outcomes.

Physicochemical, techno-functional, biochemical and structural characterization of a protein isolate from groundnut (Arachys hypogaea L.) paste treated with high-intensity ultrasound

The objective of this research was to evaluate the effect of ultrasound (HISound) (200, 400 and 600 W; 15–30 min) on the physicochemical, biochemical and structural techno-functional properties of a groundnut paste protein isolate (GPPI). HISound increased the contents of free sulfhydryls (552.22 %), total sulfhydryls (124.68 %) and α-helix (389.75 %), as well as molecular flexibility (50.91 %), hydrophobic surface (38.99 %), and particle size (171.45 %) of GPPI, which improved protein solubility by 8.05 %, oil holding capacity by 73.54 %, emulsifying stability index by 226.25 % and foaming capacity by 216.00 %, compared with non-sonicated GPPI. Also, the microstructure analysis revealed smooth structures, with molecular weights in the range of 13.88–67.07 kDa. Pearson analysis determined some highly significant correlations (r ≥ 0.90, p < 0.01) between some GPPI protein properties. The improvement of GPPI properties by HISound could contribute to its use as an ingredient for human consumption.

Highly selective split intein method for efficient separation and purification of recombinant therapeutic proteins from mammalian cell culture fluid

Biologics and vaccines have been successfully developed over the last few decades to treat many diseases. Each of these drugs must be highly purified for clinical use. Monoclonal antibodies (mAbs), the dominant therapeutic modality on the market, can be easily purified using the standard Protein A affinity platform. However, no generally applicable affinity platforms are available for the manufacture of other therapeutic proteins for clinical use. Thus, multicolumn chromatography processes for widely being used for product purification. These processes demand significant optimization to meet desired product quality attributes, where each step also decreases final yields. In this work, we demonstrate the novel self-removing iCapTagTM affinity tag, which provides a new platform for capturing, concentrating, and purifying recombinant proteins. Importantly, this system provides a tagless target protein, which is suitable for research and clinical use, where the only requirement for tag removal is a small change in buffer pH. No additional proteins, reagents or cofactors are required. We also present case studies demonstrating the use of iCapTagTM for highly efficient purification of untagged interferon alpha 2b, the ML39 single chain variable fragment (scFv), and the receptor binding domain (RBD) of SARS-CoV-2 spike protein. These proteins were expressed and secreted by Expi293 cells with the self-removing tag fused to their N-terminus. We were able to obtain highly pure (> 99%) tagless protein in a single purification step with high clearance of host cell DNA, tagged precursor, higher and lower molecular weight impurities. Based on these preliminary results, we propose the iCapTagTM as a universal capture platform for diverse classes of recombinant therapeutic proteins.

Isolation of ice structuring proteins from winter wheat in frigid region (Dongnongdongmai1) and the effect on freeze–thaw stability of dough

In this study, ice structuring proteins (WISPs) extracted from winter wheat in a frigid region were prepared and added to frozen-thawed dough. The WISPs were characterized, revealing that they contained a higher proportion of hydrophilic amino acids and had a molecular weight of approximately 15 kDa. The highest thermal hysteresis activity (THA) observed was 0.62 °C. The secondary structure of WISPs was determined to be as follows: β-sheet: 49.33 %, random coil: 13.87 %, α-helix: 16.35 %, β-turn: 20.45 %. The study investigated the effects of different additions of WISPs on the water mobility, glass transition temperature, microstructure, rheological properties, and texture analysis of frozen-thawed dough. The results demonstrated that the inclusion of WISPs reduced the fluidity of water and water migration in the dough during the frozen-thawed cycle. This protective effect preserved the internal structure and gluten network of the dough, leading to increased viscosity, elasticity, and improved texture properties of the frozen-thawed dough. Furthermore, the addition of WISPs at concentrations ranging from 0 % to 0.7 % resulted in a 1.8 °C increase in the glass transition temperature (Tg). Overall, these findings suggest that WISPs can serve as a beneficial additive for enhancing the freeze–thaw stability of dough.

Hybrid nano-biocomposite based on polysaccharide and graphene oxide for the practical separation of proteins in a fixed bed adsorption column

Proteins and amino acids are essential to humans and all living beings. Moreover, these compounds are present in the pharmaceutical, food, and cosmetic industries. Proteins need to be purified for use in industry. This work aims to synthesize and apply a nano-biocomposite based on graphene oxide (GO) and agar (polysaccharide) for protein separation and purification. The hydrogel composite was tested for myoglobin (Mb) adsorption, the effect of changing the initial pH in Mb adsorption, and the ionic strength was evaluated. The adsorptive capacity values were higher at pH=5 and 6 and decreased at higher pH values. The increase in NaCl concentration did not affect the adsorptive capacity significantly. The composite exhibited a notorious value of maximum experimental adsorption capacity in the equilibrium of over 790 mg g−1 at pH=5 and 25 °C. As GO interacts with the polymeric agar matrix, resulting in a 3D material, the material developed could adsorb Mb in a fixed bed column and single and binary (BSA+Mb) systems. There are indications that the GO-based composite possibly forms a complex with the peptide ligands of myoglobin, forming a protein corona, making Mb desorption difficult.

Improve the fiber structure and texture properties of plant-based meat analogues by adjusting the ratio of soy protein isolate (SPI) to wheat gluten (WG)

The effects of the ratio change of SPI and WG (11: 1, 10: 2, 9: 3, 8: 4, 7: 5, 6: 6 and 5: 7) on the product characteristics of plant-based meat analogues (PBMAs) were investigated. The results show that the addition of WG significantly reduces the hardness and chewiness of PBMAs, but significantly improves the springiness and brightness of PBMAs. When the ratio of SPI to WG is 9: 3, PBMAs has the best fiber structure, storage modulus and apparent viscosity. Fourier transform infrared spectroscopy (FT-IR) results showed that the transition from α-helix to β-fold was an important reason for PBMAs fibers reinforcement. The intermolecular interaction of protein shows that the enhancement of fiber structure of PBMAs is related to the increase of disulfide bonds. In this study, low cost and high simulation degree PBMAs are provided as a reference for developing PBMAs.

Ultrasound treatment on commercial pea protein isolates systems: Effect on structure, rheology and gelling properties

Pea protein has attracted great attention due to its capability to meet the growing requirements from consumers for desired nutrition and texture from plant protein. Hence, the current study aimed to investigate the effects of different ultrasonic treatment parameters (power and duration) on the gelling characteristics of commercial pea protein isolates (PPIc). The findings demonstrated that by manipulating the ultrasonic power and treatment duration, great enhancement of the solubility, adhesiveness and formation strength of PPIc gel can be realized. The reduction in particle size was positively correlated with higher power and longer treatment durations. Interestingly, no direct correlation between average particle size, solubility, turbidity, and ζ-potential was observed. Additionally, the ultrasound-modified PPIc in this study exhibited comparable characteristics to laboratory-prepared pea protein isolates, in terms of solubility, water-holding capacity, and gel strength. Overall, manipulating ultrasonic parameters presents a feasible method to customize the texture of pea-protein-based substitute.

Characterization and kinetics of whey protein isolate amyloid fibril aggregates under moderate electric fields

Food proteins solutions enable the controlled flow of electrical current when subjected to a Moderate electric field (MEF). This application results in internal heat generation, known as ohmic heating, accompanied by electrochemical reactions. These effects play a significant role in influencing the formation of protein amyloid fibril aggregates (AFA), which have broad applications in food and biomedical fields, ranging from improving food texture to biomedical applications such as drug delivery and disease treatment. This study focused on investigating the formation of β-Lactoglobulin (β-lg) AFA under MEF conditions using WPI as protein source and various characterization techniques (e.g., Thioflavin T fluorescence, circular dichroism, and electron microscopy). The results indicated that MEF prolonged the lag phase of AFA formation. Furthermore, nucleation and fibril growth showed higher activation coefficients and cooperativity level (n > 2) compared to conventional heating method. MEF treatment resulted in unique fibril clustering and the presence of unexpected higher-order AFA networks confirmed by electron microscopy. These findings highlight the significant role of MEF in influencing the aggregation kinetics of β-lg AFA. Exploring further into the electrochemical and thermal effects during protein aggregation processes holds the key to unlocking deeper insights fibril formation process.

Targeted Treatment of Kidney using Intravenous and Intraarterial delivery of Whey Protein Isolate-Based Microgels

Here we report a promising whey protein isolate (WPI)-stabilized emulsion microgels for targeted drug delivery into the kidney. Investigation of stability revealed time-dependent degradation of the microgels starting at 72 h. Cytotoxicity studies showing increased sensitivity in Hek239 and Jurkat cells. A biodegradation assay underscored the role of macrophages in the destruction process of microgel particles. The efficiency of targeting the microgels for the kidney was assessed by biodistribution using intravenous and intraarterial delivery. Tail vein administration demonstrated long-term (minimum 5 days) selective accumulation not only in the liver but also in the kidneys. Renal artery injection of microgels resulted in an expected local increase in fluorescence in the target kidney in the first minutes after injection. In contrast, at 1 and 3 h there was an atypical accumulation of the Cy7 fluorescent signal in the opposite kidney. However, at 1 and 5 d the fluorescent signal predominated in the target kidney again and was higher in comparison with intravenous administration. Histological analysis validated the safety of WPI-based microgels using different methods of administration. By fine-tuning the physicochemical properties and delivery methods, the developed microgels offer an adjusted therapeutic approach with reduced side effects. They present new prospects for the treatment of kidney disorders using both intravenous administration and minimally invasive endovascular approach.