Casein Research Articles

Amino Acid Composition of Dried Bovine Dairy Powders from a Range of Product Streams

The amino acid (AA) content of multiple samples of various dairy powders was determined, providing a comprehensive evaluation of the differences in AA profiles attributable to distinct manufacturing processes. Products examined included whole milk powder (WMP), skim milk powder (SMP), cheese whey protein concentrate (WPC-C), lactic acid casein whey protein concentrate (WPC-L), high-fat whey protein concentrate (WPC-HF), hydrolyzed whey protein concentrate (WPH), whey protein isolate (WPI), and demineralized whey protein (D90). WMP and SMP exhibited broadly similar AA profiles, with minor differences likely due to the minimal milk fat protein content, which is nearly absent from SMP. Comparative analysis of WPC-C and WPC-L indicated higher levels of threonine, serine, glutamic acid, and proline in WPC-C but lower levels of tyrosine, phenylalanine, and tryptophan, attributed to the different methods of separation from casein proteins. WPI and WPC-HF originate from similar sweet whey streams but follow divergent processing methods; consequent on this were variations in the levels of all AAs except histidine. The nanofiltration step in D90 production retains its non-protein nitrogen content and affects its AA profile; consequently, D90 consistently exhibited lower AA levels than WPC-C. These findings underscore the significant impact of manufacturing processes on dairy powder AA composition.

Soy Protein and Safflower-Seed Oil Attenuate Inflammation and Immune Dysfunction in Rats with Hyperuricemia

A plant-based diet is considered a promising approach for managing hyperuricemia (HUA). This study examined the effects of soy protein and plant-based oils on HUA-induced inflammation and immune dysfunction. Male Wistar rats, induced with HUA using oxonic acid and uric acid (UA), were fed casein or soy protein with palm or safflower oil (2 × 2 factorial design) for 8 weeks. HUA rats had lower serum albumin and T cell percentages in peripheral blood leukocytes (PBLs) and splenocytes, along with increased leukocyte counts and spleen weights, compared to healthy rats (p < 0.05). Soy protein improved HUA-induced reductions in albumin, while safflower-seed oil ameliorated reductions in albumin, plasma interleukin (IL)-4, and T-suppressor splenocytes, and mitigated elevated serum UA, plasma IL-6, and B leukocytes (two-way ANOVA, p < 0.05). In PBL, soy protein alleviated HUA-induced decreases in TNF-α, casein and palm oil increased IL-6, and casein further reduced IFN-γ production. Under Con A stimulation, casein and safflower-seed oil alleviated decreases in IL-6 and IL-10, respectively, while under LPS stimulation, casein further increased TNF-α production. In splenocytes, soy protein and safflower-seed oil reduced HUA-induced increases in TNF-α and increased IL-10, and safflower-seed oil increased IL-6 production. Under Con A stimulation, soy protein and safflower-seed oil reduced TNF-α and increased IL-10 production in splenocytes. The findings suggest that soy protein and safflower-seed oil may counteract HUA-related inflammation, alleviate monocyte activation, and enhance Th2 immune response in HUA. A plant-based diet rich in soy protein and safflower-seed oil may help manage HUA and associated inflammation and immune dysfunction.

Improvement of the properties of essential oil-starch film with whey protein isolated fibril and sodium caseinate

Essential oil-starch films are important bioactive films, but their properties are not good enough and need improved. In this work, sodium caseinate (CAS) was utilized to improve the distribution and release of Cinnamon essential oils (CEO), and whey protein isolate fibril (WPIF) of different loadings (0 %, 4 %, 8 % and 12 %, w/w) in starch basis was added to enhance the mechanical properties of starch films. Physical, mechanical, thermal, structural, antibacterial properties, and essential oil release in the films were investigated. CAS-CEO nanoemulsion (190.7±9.4 nm) promoted the compatibility between starch and WPIF. The addition of CAS-CEO nanoemulsion and WPIF synergistically enhanced the tensile strength, stiffness, crystallinity and antibacterial effects, reduced the water vapor permeability of films, and especially delayed the release of essential oil from the films. The starch film composited with CAS-CEO nanoemulsion and appropriate loading of WPIF (8 %) significantly improved the film properties, but the addition of 12 % WPIF disrupted the properties, which might be attributed to the excessive aggregation of WPIF. The work provided useful information for improving the properties of CEO films via adding the emulsifier of CAS and the texture booster of WPIF, which could help to improve the film properties containing oil-soluble bioactive agents.

Encapsulation of Monascus pigments in gel in oil in water (G/O/W) double emulsion system based on sodium caseinate and guar gum

In this study, a gel in oil in water (G/O/W) double emulsion system was developed with the objective of effectively encapsulating Monascus pigments and enhancing its stability. To this end, various formulations were prepared using guar gum co-dissolved with Monascus pigments in the internal phase and sodium caseinate as an outer phase surfactant. Different parameters were examined, including emulsion stability, encapsulation efficiency, rheological and tribological properties, as well as the light and thermal stability of the encapsulated Monascus pigments. The results demonstrated that Monascus pigments were effectively encapsulated in the G/O/W, with an encapsulation efficiency exceeding 90 %. The formulated system exhibited a relatively small particle size, which decreased with increasing guar gum and the external emulsifier contents. This resulted in an increase in viscosity accompanied by the formation of a gel-like structure and improved tribological properties, thereby enhancing the system's stability. The system with 1–1.25 % guar gum and 2.5 % sodium caseinate exhibited the highest stability for Monascus pigments, making them more resistant to heat and light. These findings have the potential to expand applications of Monascus pigments by providing a stable and effective encapsulation and delivery system that can also be utilized in the development of healthier food products.

Gel properties of mung bean protein‑sodium caseinate hybrid yogurt: Physicochemical properties, microstructure, and intermolecular interactions

The study aimed to evaluate the gel properties of mung bean protein (MP)/sodium caseinate (NaCas) hybrid yogurt at various mixing ratios, such as rheology, texture, water holding capacity, microstructure, and formation mechanism. The gel hardness, storage modulus (G′) and water holding capacity of MP/NaCas yogurt increased and subsequently decreased as the NaCas level increased, maximum at a MP/NaCas ratio of 70:30. Meanwhile, as the MP/NaCas ratio was 70:30, the hybrid yogurt gel formed tighter and finer network structure. Moreover, the MP/NaCas hybrid yogurt slowed down the acidification rate with increasing NaCas ratio. Especially when NaCas was added at 50 %, the blend sample presented the longest fermentation time (280 min). Results showed that the optimal physicochemical characteristics of the yogurt gel were obtained when MP/NaCas ratio was mixed at 70:30. The results of the intermolecular forces indicated that hydrophobic interactions were the main factor causing yogurt gel formation.

Preparation and characteristics of sodium caseinate/zein composite coating and its application effect on inhibiting the rancidity of peanut chunks

Sodium caseinate (CN) and zein were used as raw materials to prepare a composite coating applied in air system with mechanical properties, and water vapor and oxygen permeability as evaluation index. Results showed the most suitable conditions were the mass ratio of CN to zein at 0.25: 1, 60% (v/v) aqueous ethanol, polyethylene glycol (0.3 g/g) as the plasticizer, and citric acid (2.5%, w/v) as the crosslinker, and curing temperature at 50 ˚C. Under these conditions, the tensile strength of composite coating was 6.671 MPa, and the elongation at break was 97.596%. The water vapor permeability was 14.236 g·mm/(m2·d·kPa), and the growth rate of peroxide value of tung oils sealed by the composite coating was 71.300%. Results from Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and differential scanning calorimetry revealed that CN and zein were effectively crosslinked by citric acid with improved compatibility and smoother surface of the resulting coating. Results from the accelerated oxidation experiment showed that coating reduced the peroxide value and p-anisidine value of peanut chunks from 1.02 g/100 g and 6.59 to 0.62 g/100 g and 2.24, respectively, indicating that the composite coating prepared effectively inhibited the oxidative rancidity of peanut chunks.

Production performance and milk composition of late lactation dairy goats fed diets based on silages of four different forage species

The objective of the current trial was to evaluate the effect of feeding four different forage species on milk yield and composition, including protein and fatty acid profiles, in dairy goats. Two grasses (Timothy; mown at early heading, and Italian ryegrass; mown at 25 cm height) and two legumes (Alfalfa and White clover; both mown at 10% bloom) were harvested and conserved as silage. Twelve dairy goats of three different breeds (4 Alpine, 4 Toggenburg, and 4 Saanen) in late lactation were used in a replicated 4 × 4 Latin square design. Goats were offered ad libitum access to the tested forages supplemented with 180 g/d of concentrates based on rolled barley and heat-treated soybean meal. DM intake was lower with timothy, intermediate with ryegrass and white clover, and greater with alfalfa. Milk yield was lower with timothy as compared with the other three silages. Milk fat yield was similar among treatments. Milk CP yield was lower with timothy as compared with the other three silages. Milk N efficiency (N secreted/N intake) was greater with timothy, intermediate with ryegrass, and lower with the two legume silages. The proportion of true protein as a percentage of CP was lower in milk from goats fed legume as compared with grass silages. Proportions of casein and whey protein expressed as percentages of true protein were greater with timothy, intermediate with ryegrass and white clover, and lower with alfalfa. Among grass silages, intake and milk secretion of cis-9, cis-12 cis-15 18:3 was greater with ryegrass than with timothy. As a result, the transfer efficiency from dietary intake to secretion in milk was not different between these two treatments. Fewer differences were observed regarding legume forages, as cis-9, cis-12, cis-15 18:3 intake and milk secretion were similar with alfalfa and white clover. However, the transfer of cis-9, cis-12, cis-15 18:3 from diet to milk was highest when feeding alfalfa. In conclusion, forage species fed to dairy goats influence milk composition in terms of fatty acids and protein fractions, which can potentially impact the nutritive value and technological properties of milk.

RNAi library screening reveals Gβ1, Casein Kinase 2 and ICAP-1 as novel regulators of LFA-1-mediated T cell polarity and migration.

The αLβ2 integrin LFA-1 plays a key role in T-cell adhesion to the endothelial vasculature and migration into both secondary lymphoid organs and peripheral tissues via interactions with its target protein ICAM-1, but the pathways that regulate LFA-1-mediated T-cell polarity and migration are not fully understood. In this study we screened two RNAi libraries targeting G protein-coupled receptors (GPCR)/GPCR-associated proteins and kinases in a HuT 78 T cell line model of LFA-1-stimulated T-cell migration. Based on staining of the actin cytoskeleton, multiple parameters to measure cell morphology were used to assess the contribution of 1109 genes to LFA-1-mediated T-cell polarity and migration. These RNAi screens identified a number of both novel and previously identified genes that either increased or decreased the polarity and migratory capacity of these cells. Following multiparametric analysis, hierarchical clustering and pathway analysis, three of these genes were characterized in further detail using primary human T cells, revealing novel roles for the heterotrimeric G protein subunit Gβ1 and Casein Kinase 2 in LFA-1-mediated T-cell polarity and migration in vitro. Our studies also highlighted a new role for ICAP-1, an adaptor protein previously described to be associated with β1 integrins, in β2 integrin LFA-1-directed migration in T cells. Knockdown of ICAP-1 expression in primary T cells revealed a role in cell polarity, cell velocity and transmigration towards SDF-1 for this adaptor protein. This study therefore uncovers new roles for GPCR/GPCR-associated proteins and kinases in T-cell migration and provides potential novel targets for modulation of the T-cell immune response.

Variations in Bovine Milk Proteins and Processing Conditions and Their Effect on Protein Digestibility in Humans: A Review of In Vivo and In Vitro Studies.

Bovine milk proteins account for 10% of the global protein supply, which justifies the importance of thoroughly understanding their digestive processes. Extensive research on digestion is being conducted both in vivo and in vitro. However, interpretations and comparisons across different studies require a thorough understanding of the methodologies used. Both the rate and extent of milk protein digestion can be affected by several intrinsic and extrinsic factors with potential implications for overall digestibility and physiological responses. Among intrinsic factors, the impact of genetic variants in native milk proteins has emerged as a growing research area. To these, further complexity is added by the processing conditions frequently applied to milk prior to consumption. The main aim of this work is to provide an overview of the current knowledge on the impact of variations in milk protein profiles (particularly whey: casein ratio and protein polymorphisms), the treatments applied during processing (pasteurisation, homogenisation) and consumption (temperature changes) on protein digestion. To support the interpretation of the current literature, this manuscript also presents a historical perspective into research in this field and summarizes the protocols that are most frequently used, presently, on in vitro digestion studies.

The Characterization and Stability of Powdered Oil Loaded with β-Carotene Prepared from a Sodium Caseinate-Carrageenan Complex: The Effect of Vacuum Freeze-Drying and Spray-Drying.

β-carotene (BC) has various biological activities, such as anticancer properties, contributing to the prevention of cardiovascular diseases, etc., while the poor solubility and low bioavailability limit its further development in the food industry. Therefore, how to effectively encapsulate this unstable substance has become a hot topic. Here, different concentrations of sodium caseinate and ι-carrageenan (NaCas-CA) complex emulsions were used as wall materials, and the effect of spray-drying (SD) and vacuum freeze-drying (VFD) on the properties of BC powders loaded with NaCas-CA was investigated. The results showed that the characteristic peaks of BC disappeared in all powdered oils, indicating that BC could be effectively encapsulated. As the wall concentration increased, the surface oil of the powders decreased significantly. At the same concentration, the surface oil content of SD (minimum of 8.34%) was lower than that of VFD (minimum of 10.02%). However, the particle size of SD-reconstituted emulsions was larger than that of VFD. Furthermore, the SD-reconstituted emulsions were more stable than the VFD after storage at 25 °C for 3 h. This study reveals the effect of different drying methods on the structure and stability of powdered oils, providing valuable information for the research of functional active-loaded powdered oils and applications in the food industry.

Dairy sludge characteristics and its degradation during thermal treatment and thermal plasma treatment

ABSTRACT Thermal treatment and thermal plasma treatment processes of dairy sludge were conducted. The thermal treatment was undertaken at temperatures from 200 °C to 1000 °C to establish the chemical composition and thermal degradation of the sludge. These results served as a foundation for interpreting the properties of the vitreous slag obtained from the sludge treated in the DC-transferred arc plasma reactor. The dairy sludge is characterised by a high volatile matter but also presents substantial ash content, with primary elements such as Al, P, Si, Ca, and Fe. The characterisations of the samples were made employing techniques like X-ray fluorescence, X-ray diffraction analysis (XRD), FT-IR spectrometry, Thermogravimetric analysis, and Differential Scanning Calorimetry. The results highlight the degradation of primary milk components like lactose, casein protein, and milk fat, with distinct differential thermogravimetric peaks at 230, 316, and 479 °C. As the temperature of thermal treatments approached 1000°C, silicon dioxide, calcium silicon, dicalcium silicate, and hydroxyapatite were identified in XRD spectra. Plasma-treated sludge features various oxide crystalline structures, including Al2O3, CaO(Al2O3)6, CaO(Al2O3)2, Ca2Al(AlSi)O7, KFeO2, and ZrO1.98. FTIR analysis of sludge identifies a complex organic composition presenting alkanes, amines, amides, hydroxyl groups, and metallic and semi-metallic oxide bond absorption. The FTIR results suggest the degradation of organic compounds and retention of phosphorous and aluminum bonds, especially after 600 °C. The vitreous slag from plasma treatment exhibits distinct composition characteristics without organic compound, presenting a vitreous and metallic/ceramic matrix. This research underscores the potential of thermal plasma treatments to neutralise dairy sludge.

Piperine‐Loaded Sodium Caseinate Nanoglobules Delivered Transdermally Through Microneedle Patch for Improved Bioavailability at Adipose Tissue

ABSTRACTDespite being a well‐known anti‐obesity chemical, piperine has only found limited therapeutic use because of its poor bioavailability at the site of action. In order to test this hypothesis, we placed piperine sodium caseinate nanoglobules (PSN) in microneedle patches (MNPs), which may enhance piperine transdermal delivery and absorption. Clove oil, sodium caseinate to make nanoglobules, and PEG 400 as a stabilizer were used in a nanoglobules process to create the PSN. The polydispersity index (0.256) and particle size (134.4 nm) of the developed PSN were both smaller, while their zeta potential (−44.4 mV) and encapsulation efficiency (90%–95%) were both greater. Compared to native piperine, the PSN increased solubility, bioaccessibility (6.5 times), and bioavailability (2.8 fold). Moreover, the PSN‐loaded MNPs were created using the micro‐molding (poly‐dimethylsiloxane (PDMS) mold) approach. In both PBS buffer and porcine skin, the PSN‐loaded MNPs were rapidly hydrolyzed, with 50% piperine release in less than 5 min. Also, the produced MNPs demonstrated improved bioavailability of piperine in the plasma (180 ng/mL) and adipose (425 ng/mL) tissue of C57BL6 mice. In conclusion, the work offered a theoretical foundation for utilizing new PSN‐loaded MNPs as a viable piperine delivery method for treating obesity.

Towards hybrid protein foods: Heat- and acid-induced hybrid gels formed from micellar casein and pea protein

Given the rising demand for more sustainable, cookable dairy alternatives, this research explores the formation and characteristics of heat- and acid-induced gels combining micellar casein and pea protein. Protein dispersions (4 % w/w) of commercial micellar casein isolate and pea protein isolate were prepared and preheated (95°C, 30 min) separately before mixing in varying ratios (75:25 %, 50:50 %, and 25:75 % w/w). After emulsifying with milk fat (3.5 % w/w), the protein mixtures were heated to 80 °C and acidified to pH 5.2 (citric acid). The resultant coagula were pressed, drained, and molded to obtain the final gel. It was observed that adding pea protein led to a higher yield of coagula with more serum retained. As the proportion of pea protein increased, the total solids (TS), protein, and fat content of the gels decreased linearly. The micellar casein gel showed significantly higher hardness, elasticity, and chewiness than the gels containing pea protein. Moreover, the micellar casein gel did not show clear fracture behavior under large deformation, while the gels containing pea protein were more prone to rupture. These textural differences were explained by the changes in gel compositions, protein interactions, and gel microstructure. The composition and textural properties of hybrid gels showed a strong linear relationship with pea protein fractions, showing the possibility of customizing gel properties. Notably, the hybrid gel containing 25 % pea protein exhibited promising characteristics, closely resembling those of the commercial dairy paneer product.

Determination of Plasma Metabolites and Basal Ileal Endogenous Amino Acid Losses in Growing Pigs Fed a Nitrogen-Free or Casein Diet.

The nitrogen-free diet (NFD) method for determining basal ileal endogenous losses (BEL) of amino acids (AA) has been associated with different metabolic abnormalities that can affect the accurate determination of BEL. Consequently, the use of highly digestible proteins has been suggested. This study aimed to determine the metabolic status and BEL of AA in pigs fed either an NFD or a casein (CAS) diet. Eight cannulated, castrated male pigs (39.8 kg) were randomly assigned to a 2 × 2 crossover design. An NFD diet based on corn starch, dextrose, cellulose, oil, vitamins and minerals was used. The CAS diet was equivalent, but 18% of the corn starch was replaced with casein. Pigs were fed one of the diets for a 7-day period, and blood samples were collected at the beginning and end of each period to determine plasma metabolites. Ileal digesta samples were collected on Days 6 and 7 to estimate the BEL of the AA. Results indicated that plasma albumin was significantly higher (p < 0.05) in pigs fed the CAS diet, whereas creatinine and LDL levels were higher (p < 0.03) in pigs fed the NFD. No significant differences were observed in the levels of other plasma metabolites. The BEL of protein did not differ between diets. However, in pigs fed the CAS diet, the BEL of glutamic acid, aspartic acid, serine, glycine, histidine, threonine, alanine, tyrosine and valine significantly increased (p < 0.05), while isoleucine showed a tendency to increase (p = 0.06). In conclusion, NFD did not significantly affect energy and lipid metabolism in pigs. However, the decrease in albumin synthesis and increase in plasma creatinine levels indicate that pigs fed NFD have a negative protein balance, affecting the estimation of the BEL of AA. Therefore, it is essential to consider the metabolic state of animals when estimating the BEL of AA.

Neutrophil-activating protein in Bacillus spores inhibits casein allergy via TLR2 signaling.

Milk allergy commonly occurs in children, mainly caused by bovine-derived casein (CAS) protein. Neutrophil-activating protein (NAP) of Helicobacter pylori plays an immunomodulatory role with potential to suppress Th2-type immune responses. Bacillus subtilis (B. subtilis) spores are commonly used as oral vectors for drug delivery. To investigate whether recombinantly expressed NAP on B. subtilis spores could be an effective treatment for CAS allergy in mouse. After CAS sensitization, mice were orally administered B. subtilis spores expressing recombinant NAP for 6 weeks. Allergic symptoms and parameters were evaluated after CAS challenge oral gavage, including allergic inflammation, splenic cytokines, and serum-specific antibodies. Protein levels of Toll-like receptor 2 (TLR2) and c-JUN in the jejunum tissue were measured by western blot. Bone marrow-derived macrophages (BMDMs) were stimulated with inactivated NAP spores to measure the influence on cytokine profiles in vitro. NAP recombinant spore treatment significantly reduced allergic symptoms and intestinal inflammation. Interleukin-12 and interferon-gamma levels increased, whereas serum CAS-specific IgG1 and IgE levels decreased. TLR2 and c-JUN expression levels were elevated in the jejunal tissue. Inactivated NAP spores polarized BMDMs to the M1 phenotype and enhanced cytokine expression, which were inhibited by a TLR2 neutralizing antibody. NAP offers a new strategy in the treatment of CAS allergy by inhibiting the Th2 response, while eliciting macrophages to promote Th1 immune responses.

Functional, structural, and rheological properties of the complexes containing sunflower petal extract with dairy and plant-based proteins

This study aims to investigate the impact of sunflower petal extract (SFE) on the functional and structural properties of sodium caseinate and chickpea proteins. For this purpose, 3.5 % of sodium caseinate solution and 3.5 % of protein extracted from chickpea powder were prepared in phosphate buffer (pH = 7). SFE was used at different concentrations, from 1 to 3 % in different protein solutions and functional, structural and rheological properties were measured. The results revealed that complexation of SFE with different proteins can enhance the antioxidant, foaming properties, solubility, emulsion activity, emulsion stability, viscoelastic behavior, and can decrease surface hydrophobicity. FTIR and docking results showed that the most bonding type was non-covalent bonds. Major phenolic compounds containing heliannone A, B, and kaempferol had strong affinity with sodium caseinate, and then chickpea protein. Therefore, the results demonstrated that SFE and its complexes had appropriate emulsifying properties that reduces interfacial tension in the water/oil interface.

Casein and acryl amide complexation and bio-adhesive polymeric nano micelles influence on vortioxetine dissolution, penetration enhancement and in vivo absorption

Vortioxetine (VTX) is a new atypical antidepressant used to treat major depression and other mental disorders. Due to its low water solubility, oral absorption, and fast metabolism, VTX has been commercially manufactured and sold as a hydrobromide. Long-term VTX hydrobromide therapy is frequently associated with respiratory irritation and digestive dysfunction. Two techniques were developed for dissolution, swelling, adherence, and penetration enhancements. The techniques were the VTX and casein (CAS) complexation using the maximum loading capacity, and VTX-polymeric nano micelle using the “Sandwich Technique”. This study includes the maximum VTX-CAS binding capacity determination, VTX-CAS complex preparation, polymeric nano micelle encapsulating VTX-CAS complex optimizations, physiochemical characterisations, solubility assessment, VTX release analysis, swelling analysis and mucus-penetrating study of the VTX-CAS complex and VTX polymeric nano micelle in comparison to the VTX raw material. The optimum VTX-polymeric nano micelle dissolution, swelling, adherence, and penetration enhancements were supported by the results of 91.10±16.34 nm, +19 mV zeta-potential, structural arrangements, and enhanced amorphic character with the morphology and size distribution (50–100 nm). The VTX-polymeric nano micelle could serve as an oral alternative to the VTX hydrobromide therapy based on the results of the biocompatibility and in vivo absorption studies for the VTX-polymeric nano micellar system.

Fabrication and physicomechanical performance of κ-carrageenan/casein nanofibers

The low molecular weight of casein proteins (19–25 kDa) and their self-aggregation limit the electrospinnability of casein nanofibers. Here, the influence of ethanol content (0–60 %) and temperature (20–80 °C) on the state of κ-carrageenan dispersions and their subsequent influence on the electrospinnability and physicomechanical attributes of casein-based EMs was evaluated. κ-carrageenan/casein dispersions prepared at 50% ethanol, pH 10, and 60 °C resulted in the formation of EMs with few bead defects. These conditions lead to the dissociation of casein aggregates and the transformation of κ-carrageenan conformation. More uniform fibrous morphologies with minimum bead defects (2.0 x 10−3/μm2) were obtained for 1 wt % κ-carrageenan in casein EMs. A maximum strength of ∼0.2 MPa and modulus of ∼12 MPa was obtained for as spun mats with 1 wt% κ-carrageenan in casein. On exposure to a relative humidity of 100% for 48 h, these mats adsorbed 140 % of their weight in water, became solid films, and increased in strength and modulus >10-fold with a 2-fold decrease in elongation at break. This study demonstrates the influence of κ-carrageenan on the electrospinnability of casein proteins to fabricate novel biodegradable casein-based nano-structured mats with potential for food, cosmetic, packaging, and biomedical applications.

Drugs and other substances aggravating acne vulgaris

Introduction and Purpose This review explores several factors exacerbating acne, including the supplementation of vitamins B6 and B12, the impact of red ginseng oil, dairy and whey product consumption, iodine association, anabolic-androgenic steroids, alcohol abuse, and the influence of progestin contraceptives. Material and methods This review is based on articles from the PubMed database, covering the years 2018-2023, using keywords: acne vulgaris, acne vulgaris aggravation, substances aggravating acne vulgaris. Results High doses of B6 and B12 have been reported to worsen acne, potentially linked to their prolonged use. Red ginseng oil, believed to have numerous health benefits, may exacerbate acne symptoms by increasing inflammatory biomarkers. Dairy consumption, specifically casein and whey proteins, is associated with increased insulin-like growth factor 1, contributing to acne aggravation. Iodine has been extensively linked to acneiform eruptions, and its correlation with dairy consumption is hypothesized. Anabolic-androgenic steroids, found in muscle-building supplements, elevate sebum production and may cause acne fulminans. Alcohol abuse further intensifies acne symptoms by impacting testosterone levels, promoting proinflammatory cytokine production, and altering the skin microbiome. Progestin contraceptives, particularly levonorgestrel and etonorgestrel, exhibit androgenic properties that may increase sebum production and potentially aggravate acne. Conclusions Understanding and identifying these exacerbating factors are crucial for healthcare providers to enhance anti-acne therapy outcomes, emphasizing the importance of not only treating but also preventing the escalation of acne manifestations in patients.

Regulation mechanisms of allergenic epitope sites in casein by microbial and plant-derived proteases

Casein (CN) is the primary factor leading to allergic reactions in infants to bovine milk, severely limiting the intake of bovine milk formula by allergic infants. This study investigates the conformational changes and regulation of linear epitopes during the hydrolysis of CN by five proteases derived from microbial and plant sources using multiple spectroscopic techniques combined with LC/MS-MS. The results showed that the IgE inhibition rates for SD (subtilisin hydrolysate), PD (papain hydrolysate), BD (bromelain hydrolysate), KD (proteinase K hydrolysate), and FD (ficin hydrolysate) were 43.19%, 41.99%, 35.45%, 48.15%, and 14.80%, respectively. The differences in antigenic residues remaining after hydrolysis by different proteases mainly result from the varying degrees of structural alteration of CN and the hydrolysis allergic epitope regions. This study provides theoretical basis for understanding the mechanism by which proteases reduce the allergenicity of CN. It also offers new insights into the development of multienzyme combinatorial hydrolysis strategies.