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Abstract A series of different eggshell membrane (ESM) and chitosan (CS) blend films (ESM/CS) were prepared for wound-care dressing. The appearance, transparency and microstructure of the films were characterized. Several wound care-related properties such as the film integrity in solution, pH, protein (BSA) and wound fluid absorption capacity as well as the antibacterial property of ESM/CS films were evaluated. The blend films were more stable than CS film after 95 h of incubation in solution. The integrity of the blend films improved significantly at the cost of a small insignificant decrease in wound fluid absorption capacity. Besides, the blend films provided an acidic environment (pH = 5.86) for wound healing. The swelling properties of ESM contributed significantly to the increase of BSA absorption capacity of the blend films (from 46.57 mg/g of CS film to 61.07 mg/g of blend film) and helped absorb more nutrients to promote the proliferation and migration of fibroblasts. Addition of CS to ESM also enhanced the antibacterial activity of the films significantly. The results indicated that the EMS/CS blend films with 0.01 g ESM/mL CS solution showed the highest high potential to be used as a wound-care dressing for humans as well as animals. Highlights • We successfully prepared a new type of blend films with an outstanding wound-care properties. • The wound healing dressing of the blend film composed of chitosan and eggshell membrane was prepared for the first time. • Several wound care-related properties were improved with the incorporation of ESM and glycerol into chitosan film. [ABSTRACT FROM AUTHOR]

An efficient one-step grafting approach was developed to modify ovalbumin (OVA) by phosphorylation through selective reaction with the hydroxyl group of Ser and Thr residues present in OVA. The site-specific phosphorylated conjugates were characterized by Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry (MALDI-TOF/MS) and the results indicated that the Ser residue could be more readily phosphorylated, and the typical phosphopeptides 264 LTEWTSSNVMEER 276 and 340 EVVGSAEAGVDAASVSEEFR 359 demonstrated the formation of monophosphoester. Moreover, 13 C NMR analysis showed that the βCH 2 of Ser acted as a hydroxyl donor to react with sodium tripolyphosphate (STPP), and the conjugates with variable phosphorylation sites could improve the weak network and the resulting poor mechanical properties of ovalbumin-based hydrogels. Furthermore, small-amplitude oscillatory measurements, creep recovery tests and texture profile analysis of hardness and stickiness indicated that phosphorylation can strengthen the intermolecular cross-linking of protein molecules and produce significant influence on the rheological behavior and texture properties, suggesting that a suitable conjugation site is essential for the best gelation properties at a different pH. The integrated results indicate that phosphorylation change significantly modify the viscoelastic and mechanical properties of OVA-based hydrogels by changing molecular dynamics upon heating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acylation of OVA significantly improved the gel properties of hydrogels. • Acylation modification effectively promoted the formation of network structures in OVA hydrogels. • Acylation modification effectively enhanced hydrophobic interactions during thermal gelation. • Acylated OVA hydrogels exhibited a delayed drug release of curcumin. In this paper, the effects of acylation modification on the gel behavior of ovalbumin (OVA) under heating induction have been investigated. From the obtained results, the acylated OVA hydrogels exhibited superior gelation properties than the native OVA hydrogels (NOVA-G) in terms of light transmission, gel hardness, resilience and water holding capacity. SEM revealed acylation modifications effectively promoted the formation of uniform and dense network structure of OVA hydrogels. The main intermolecular forces of the acylation-modified OVA hydrogels were hydrophobic interactions and hydrogen bonding. FTIR showed that acylation modifications caused 26.2% decrease in α-helix and 59.2% increase in β-sheet content compared to NOVA-G. Furthermore, in-vitro release experiments showed that the release rate of curcumin from acylated OVA hydrogels was significantly delayed. Moreover, the above results have shown that acylation modifications can be considered as an effective method to improve the gelation as well as drug release properties of protein hydrogels. [ABSTRACT FROM AUTHOR]

Duck eggs are nutritious and healthy diet and their properties further increased after being preserved by alkaline treatments. Preserved eggs are widely used as functional food products most probably as an alkalescent food posing several benefits to human health. An alkaline treatment increased their functional properties as a functional food ingredient, as well as their anti-inflammatory and anti-cancer properties are also enhanced. This review was aimed to accumulatively review functional properties of preserved eggs as an excellent food ingredient and as an excellent anti-inflammatory food. Hence, we have deeply reviewed the functional properties of preserved eggs as a functional food product with emphasis on their improved functional properties while preservation. Furthermore, we have given deep insights into rationale for alkaline pH in cell and cancer microenvironment in order to get better understanding about the health benefits of alkalescent food. At last, the detailed knowledge about anti-inflammatory and anti-cancer role of preserved eggs as an alkalescent food has been discussed at cellular level which made us aware of its importance for regular intake in our daily life for better health. However, there is still a lack of knowledge about this aspect in the research field and might rarely reviewed; hence this review will be promising in providing deep insights and further ideas for research conductance. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) is a lethal genitourinary cancer and accounts 3% of total cancers worldwide. Various pleiotropic cytokines, i.e activator of signal transducer and activator of transcription 3 (STAT3), Cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (c-FLIP) and interleukin-6 (IL-6) could act to block the process of apoptosis in renal cancinoma cells, trigering its growth and proliferation. Their over-expression could activate several anti-apoptotic factors, hence it is important to block or down-regulate such factors in order to activate apoptosis in cancer cells. Up till now, several chemo and radiotherapies are being considered to combat renal carcinoma cells; however, there is a strong need to get some dietary therapeutic treatment. Hence, this study has used gastrointestinal digests of preserved eggs (GID-PE) for the apoptosis of Caki-1, ACHN and 786-O cells lines, in order to get insights about apoptosis in their mitochondrial pathway before and after treatment with (GID-PE). Moreover, changes in morphology accompanied by apoptosis analysis with different treatments have been carried out. Furthermore, ELISA analysis and mRNA expression of certain pro-inflammatory and anti-inflammatory cytokines were determined before and after treatment with GID-PE. Furthermore, the specific anti-apoptotic genes, i.e cFlip, Mcl-1, Bcl-XL and STAT3 were examined for their down-regulated expression after different treatments with GID-PE. Moreover, Bax expression acting as a pro-apoptotic gene was up-regulated up to some extent after treatments with GID-PE. Hence, GID-PE was confirmed to give anti-inflammatory effects in renal carcinoma cells could be used as health beneficial food product with anti-cancer properties. [ABSTRACT FROM AUTHOR]

This study aims to enhance the color and microbiological qualities of a raw beef using natural ingredients. Nitroso-hemoglobin (NO-Hb) integrated with vitamin C (VC), calcium lactate, and ginger complexation were used as natural inhibitors against the growth of aerobic and pathogenic bacteria, namely (Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Salmonella. NO-Hb inhibited E. coli , S. aureus , and Salmonella , and enhanced the color stability more than nitrite in the minced beef model. After the multiexponential analysis of relaxation decays, the water component (T 2b) was analyzed using the low-field NMR. The results indicated that, at the 7th d of cold-storage the third component (T 2) was detected. Significant correlations were observed between T 21 and T 22 relaxation times and water-holding capacity in minced beef, implying that the LF-NMR measurements could be an efficient method for the determination and prediction of beef freshness. NO-Hb- ginger mixture, as a novel ingredient, could be used instead of nitrite in terms of meat safety. • NO-Hb, from fresh beef blood and use as a nitrate substitute • NO-Hb, VC, Ca, and ginger addition improve color and inhibit of bacteria. • NO-Hb, used as a novel ingredient used in term of safely • LF-NMR has been clearly established the changes in T2 of water. [ABSTRACT FROM AUTHOR]

Preserved eggs are a type of egg products made from duck eggs and have anti-inflammatory activity. The purpose of this study was to investigate the effects of preserved egg simulated gastrointestinal digests on the apoptosis of HT29 and HepG2 cells. The cells morphology, apoptosis and apoptosis associated genes (Bcl-2, Bax, COX-2) and proteins (caspase-3 and caspase-9) were evaluated. The results showed that preserved egg digests significantly up regulated the expression of genes Bax, caspase-3 and caspase-9, which are involved in cell apoptosis, and up regulated the expression of the pro-apoptotic factors Bcl-2 and COX-2 both in HT29 and HepG2 cells, leading to a reduction in the ratio of Bcl-2:Bax proteins. The results also showed that the apoptosis of HT29 and HepG2 cells was promoted by the PED in a dose-dependent manner. Thus, PED may serve as a potential functional food for cancer treatment. • The anticancer activity of preserved eggs was explored. • Preserved eggs digests promoted HT29 and HepG2 cells apoptosis in a dose dependent manner. • Preserved eggs significantly up regulated the expression of genes Bax, caspase-3 and caspase-9. [ABSTRACT FROM AUTHOR]

As two major proteins of egg white, the interaction between lysozyme (LYZ) and ovalbumin (OVA) has been studied. In the present research, the mechanism and kinetics of the interaction between LYZ and OVA were studied using several methods, including cyclic voltammetry (CV), dual polarization interferometry (DPI) and surface plasmon resonance (SPR), and the effect of their interaction on the activity of LYZ was investigated using a bacteriolytic activity assay. Cyclic voltammograms showed that there was an interaction between these two proteins. DPI results indicated that the interaction is a type of chimeric mode, and the K A and K D of the interaction were 498 and 2.01 × 10−3 mol/L, respectively, calculated from the fitting of the surface plasmon resonance curve. The bacteriolytic activity assay showed that the interaction between these two proteins reduced the bacteriolytic activity of LYZ. [ABSTRACT FROM AUTHOR]

This study investigated the impact of ultrasound pretreatment and phenolic binding on the structure characteristic and foaming properties of egg white (EW). EW treated without ultrasound (NEW) and with ultrasound (UEW) (power for 28% and time for 25 min: on-time 3 s and off-time 2 s) were incubated separately at 25 °C for 2 h with gallic acid (GA) and epigallocatechin gallate (EGCG) at pH 7.0. Phenolic treatment caused a significant loss of sulfhydryl content, with a more remarkable effect observed in UEW, especially at 120 μmol/g concentration. Both phenolics significantly decreased the surface hydrophobicity and slightly increased the disordered secondary structure of protein. Additionally, the microenvironment polarity of protein molecules was increased by phenolic treatment corroborated by UV absorption blue shift, especially for 240 μmol/g GA-UEW. After ultrasound pretreatment, low EGCG concentration (20 μmol/g) significantly increased the foaming ability. The 240 μmol/g EGCG treatment notably increased the reduced foaming stability by ultrasound from 81.00 to 95.10% (p < 0.05), which was due to high absolute ξ-potential value. This study has shed light on the mechanisms underlying the influence of unfolding structure by ultrasound treatment on phenolic binding. Image 1 • Phenolic treatment especially EGCG significantly decreased sulfhydryl content. • Protein surface hydrophobicity was obviously decreased by phenolic treatment. • EGCG treatment increased the foaming stability of egg white. • EGCG was stronger than GA in binding affinity with egg white. • Ultrasound pretreatment contributed to the binding of phenolic to protein. [ABSTRACT FROM AUTHOR]

Obesity induced by consuming a high-fat diet (HFD) is a major risk for nonalcoholic fatty liver disease, which has become a worldwide health problem. To study the effects of high-density lipoproteins of egg yolk (EYHDL) on mice with HFD induced obesity, lipidomic analyses using ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was done with serum and liver samples on 60 and 100 days. The results showed that EYHDL significantly alleviated mouse obesity by decreasing adipose tissue accumulation, serum low-density lipoproteins cholesterol, total cholesterol, hepatic triglycerides and development of hepatic steatosis. The EYHDL group was separated from HFD on the orthogonal partial least squares-discriminant analysis score plots, suggesting the beneficial effect of EYHDL on dyslipidemia in obese mice. Volcano plots combined with S-plots showed that the potential biomarkers contributing to these differences were diglycerides, phosphatidylcholines, phosphatidylinositols and lysophosphatidylcholines. On the basis of these biomarkers, glycerophospholipid metabolism is probably the main pathway regulated by EYHDL in obese mice. In summary, EYHDL alleviated hyperlipidemia in obese mice by regulating the phosphatidylcholines and neutral glycerolipids composition, and the lipid biomarkers can be used to better assess the mechanism and therapy for HFD-induced obesity. Image 1 [ABSTRACT FROM AUTHOR]

• Phosphorylation improved the calcium chelating ability of collagen peptide. • Both PCP and PCP-Ca could promote MC3T3-E1 cell the mRNA level of ALP, Runx2, OCN, OPN and Col 1. • PCP-Ca had significant effect on mineralization of MC3T3-E1 cellt. In this study, porcine bone collagen peptide (CP) was phosphorylated with sodium tripoly phosphate (STP) in order to improve its calcium binding capacity and osteogenic activity. Firstly, the phosphorylation process were optimized by an orthogonal experiment. Then, the effects of CP, phosphorylated CP (PCP), CP-calcium chelate (CP-Ca) and PCP-Ca on proliferation, differentiation and mineralization of MC3T3-E1 cells were investigated. The results showed that all of the CP, PCP, CP-Ca and PCP-Ca could enhance the proliferation, differentiation and mineralization of MC3T3-E1 cells by increasing the mRNA expression levels of alkaline phosphatase (ALP), Runt-related transcription factor-2 (Runx2), osteocalcin (OCN), osteopontin (OPN) and collagen type I (Col I), as well as the protein expression levels of Runx2 and β-Catenin. Especially, PCP-Ca had the greatest and significant effect on mineralization of MC3T3-E1 cells (P < 0.05). These results suggested that phosphorylation is a promising method to improve the calcium binding capacity and osteogenic activity of collagen peptides. [ABSTRACT FROM AUTHOR]

This study was focused on the differences between three concentrations of four safe bio-active volatile terpenes and natural compounds (trans-cinnamaldehyde, thymol, menthol, and vanillin) on the egg yolk volatile components. In which, Headspace Solid phase Micro Extraction (HS-SPME) followed by GC/MS were used for volatiles analysis, and electronic nose (E-Nose) with 18 sensors was used for the aroma pattern. In the results, a total of 111 different volatile compounds were identified by using GC/MS. Some ketones, amines, nitro and organic acid compounds such as hexanone were significantly reduced after using these compounds. On the other hand, first principal components (PC1) of trans-cinnamaldehyde (0.1%) was decreased significantly (p <.05) to −4.8 ± 0.8, compared to the control with 4.3 ± 2.1. And, it increased benzaldehyde and nonanal peaks area significantly to 46.56 ± 14.46 and 9.22 ± 4.81 MPA. In menthol (0.1%), the content of d-limonene was decreased to 4.65 ± 0.49 MPA, compared to the control with 14.16 ± 4.95 MPA. On the other hand, by E-Nose, vanillin (0.1%) PC1 was decreased significantly to −4.48 ± 0.43. Moreover, thymol (0.1%) decreased hydrocarbon sensation to 0.448 ± 0.005. And, vanillin (0.1%) decreased hydrogen sulfide and ketones sensation to 0.169 ± 0.01 and 0.344 ± 0.01, respectively. In conclusion, this study is providing novel information to understand the effects of bio-active molecules on the biological fatty media volatility. Also, it explains how terpenes can protect egg yolk media from the unacceptable odor formation which results from the degradation of its lipids and proteins. Unlabelled Image • One hundred eleven different volatile compounds were found by HS-SPME-GC/MS. • Hexanal, nonanal, and benzaldehyde showed positive volatiles PC1 and negative PC2. • Trans-cinnamaldehyde and thymol significantly decreased yolk ketones. • Azulene was formed in trans-cinnamaldehyde and thymol (0.1%). • A significant negative correlation was found between PC1 of volatiles and E-nose. [ABSTRACT FROM AUTHOR]

In this study, a proteome analysis of Tibetan chicken egg yolk as well as the comparison to that of lowland chicken were performed by label-free quantitative proteomics. A total of 135 proteins were identified and abundances of 19 of these proteins were significantly different between these two groups. These differential proteins were mainly associated with oxidative stress, defense, energy metabolism and tissue development through bioinformatics analysis. To further verify the species-specific diversity of the antioxidant capacity, the antioxidative activities of egg yolk proteins were further invested in vitro and in Caco-2 cells. It was observed that both Tibetan and lowland chicken egg yolk proteins showed antioxidant activities, but the former exerted a much stronger effect. PIT54 and glutathione peroxidase 3 were considered to be antioxidant-related candidate proteins. These results provide substantial evidence for the molecular mechanisms of enhancing physical activity levels of egg yolk proteins, especially with regard to the cross-species protective mechanisms against oxidative stress. [ABSTRACT FROM AUTHOR]

This experiment was conducted to explore the differences of serum steroid hormones with age and sex in hen eggs during incubation periods for identification of males and females. The concentrations of estrone (E1), estradiol (E2), estriol (E3), testosterone (T), androstenedione (A4), and dihydrotestosterone (DHT) in serum were measured by enzyme-linked immunosorbent assays in chicken embryos on 8, 10, 12, 14, and 16 D, respectively. During the development of chicken embryo, egg weight loss was closely related to age but no sex. However, it was found that both age and sex significantly affected hormones and had obviously more effect on androgens levels. Besides E2 and T, other steroids such as E1, A4, and DHT were also significantly correlated with sex (P < 0.05). Notably, the level of T and the ratio of T to E2 were significantly higher in males than females (P < 0.05). The ratio of E1 to E2 displayed different trends in different sexes, which increased in males but decreased in females. The distribution proportions of androgens and estrogens kept stable level during the late hatching periods of 12 to 16 D. The sex differences of steroids were more obvious at the late hatching stage through PCA. These suggested that the serum hormones differences in male and female embryos played a vital role in sexual differentiation. These findings not only provided the theoretical basis for sex determination of fertilized eggs in egg-laying hen strains, but also contributed to develop a non-invasive way to sex determination of fertilized eggs to meet the modern commercial application. [ABSTRACT FROM AUTHOR]

Phosphorylation of phosvitin has been proved to play an important role in the mineralization, but the active region of phosvitin is still not known yet. Four phosvitin phosphopeptides (PPPs) were obtained after separating from ion exchange column and desalting from gel filtration, and named as PPP0, PPP1, PPP3 and PPP4, respectively. The effect of PPP on the mineralization was investigated by pH-stat system, Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. SDS-PAGE and circular dichroism were applied to study the composition and the structure of PPP. Results showed that the order of promoting mineralization was as follows: PPP3 > phosvitin > PPP4 > PPP1 > control > PPP0. PPP0 and PPP1 was not involved in the mineralization, while the structure of PPP4 was too compact to promote mineralization because of its high β-sheet conformation. PPP3, which contained a 10 kDa peptide, is the most effective promoter for mineralization. LTQ-MS/MS results indicated that the phosphorylated serine clusters of phosvitin was the active region for promoting mineralization. [ABSTRACT FROM AUTHOR]

Phosvitin is a unique highly phosphorylated protein that plays a role in the regulation of mineralization. This study investigated the role of phosphorylation of phosvitin in the phase transformation of calcium phosphate in the mineralization solution. Partially dephosphorylated phosvitins (T1, T2, T3 and T4) were prepared with 2.98, 19.46, 43.39 and 71.07% of phosphate released from native phosvitin, respectively. And their effect on regulating the phase transformation was investigated, the characterization and composition analysis was performed by circular dichroism, Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Results showed that phosvitin in the acceleration effect of phase transformation was dose-concentration effect by pH-stat titration. With lower dephosphorylation degree of phosvitin (<20%), the acceleration effect was weaker than native phosvitin, since phosphorylation and random structure of phosvitin were reduced. However, with higher dephosphorylation degree of phosvitin (>40%), the acceleration effect was enhanced compared to native phosvitin, in which the β-sheet structure was increased and phosvitin was partially hydrolyzed to phosphopeptides. The acceleration effect of phase transformation was as follows: T4 > T3 > phosvitin > T1 > T2 > Control. This study clearly demonstrated that phosphorylation of phosvitin played an important role in the regulation of mineralization. [ABSTRACT FROM AUTHOR]

Chitin is the most abundant natural amino polysaccharide, showing various practical applications owing to its functional properties. However, there are barriers in the development due to the difficulty of chitin extraction and purification, regarding its high crystallinity and low solubility. In recent years, some novel technologies such as microbial fermentation, ionic liquid, electrochemical extraction have emerged for the green extraction of chitin from new sources. Furthermore, nanotechnology, dissolution systems and chemical modification were applied to develop a variety of chitin-based biomaterials. Remarkably, chitin was used in delivering active ingredients and developing functional foods for weight loss, lipid reduction, gastrointestinal health, and anti-aging. Moreover, the application of chitin-based materials was expanded into medicine, energy and the environment. This review outlined the emerging extraction methods and processing routes of different chitin sources and advances in applying chitin-based materials. We aimed to provide some direction for the multi-disciplinary production and application of chitin. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, ovalbumin (OVA) was phosphorylated by dry-heating at three different pH values (5.0, 7.0 and 9.0) and 45 °C for 12 h in the presence of sodium tripolyphosphate (STP). The results indicated that, when compared with native OVA (N-OVA), the zeta potential absolute value of phosphorylated OVA (PP-OVA) increased from 2.13 mv (N-OVA) to 13.57(PP-OVA-pH5.0), 16.00(PP-OVA-pH 7.0) and 11.20 mv (PP-OVA-pH 9.0); the volume-weighted mean diameter (D [4,3])of emulsions stabilized by the N- and PP-OVA decreased from 70.22 μm (N-OVA) to 37.16(PP-OVA-pH 5.0), 16.21(PP-OVA-pH 7.0) and 43.52 μm (PP-OVA-pH 9.0); and PP-OVA emulsions exhibited a more narrow monomodal size distribution and a smaller particle size than those of N-OVA, with the corresponding emulsifying activities index (EAI) increased from 92.71(N-OVA) to 142.51(PP-OVA-pH5.0), 224.88(PP-OVA-pH 7.0), and 150.97(PP-OVA-pH 9.0), respectively. The microscopic observation showed that the emulsion droplets of PP-OVA were more densely and uniformly distributed than those of N-OVA. Furthermore, characterization of PP-OVA by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and 31 P nuclear magnetic resonance ( 31 P NMR) revealed that phosphate groups were bound to the -OH on serine and threonine and the -NH 2 on lysine and arginine, with covalent interactions (C–O–P and C-N-P bounds) formed between OVA and STP. This study demonstrated that the introduction of phosphate groups could increase the amount of negative charge and intermolecular repulsion, decrease the particle size of droplets and improve the emulsifying ability of PP-OVA. [ABSTRACT FROM AUTHOR]

This paper studies the metabolic pathway of sucrose in pullulan fermentation by Aureobasidium pullulans . Because of its high pullulan production, sucrose proved to be the best carbon source for pullulan synthesis by A. pullulans CGMCC1234 (36.3 g/L). Compared to other carbon sources, A. pullulans cells reached the stationary phase more quickly in the presence of sucrose. The specific sugar types and concentrations occurring during pullulan fermentation were detected using High Performance Liquid Chromatography (HPLC). HPLC results revealed that sucrose did not simply break down into glucose and fructose in the medium employed. Kestose (22.69 g/L) also accumulated during early stages of fermentation (24 h), which reduced the osmotic pressure of the extracellular fluid and diminished the inhibition of cell growth and pullulan production. β-Fructofuranosidase activity strongly depended on the carbon source. Sucrose was the best inducer of β-fructofuranosidase production. However, β-fructofuranosidase production did not directly and/or proportionally correlate with the growth of A. pullulans cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel chitinase EaChi40 was isolated from Exiguobacterium sp., and its gene was expressed in E. coli BL21 (DE3). • Recombinant chitinase EaChi40 showed good cold-adapted catalysis and thermal stability. • Crayfish shell was treated with ball milling and ultrasonic-assisted decolorization to promote enzymatic hydrolysis. • EaChi40 effectively bio-transformed crayfish shell chitin by producing chitin oligosaccharides. Crayfish have become a heavily consumed food and its chitin-rich shell is of great value in terms of waste conversion. This study found a novel chitinase (EaChi40) from a marine bacterium Exiguobacterium antarcticum. The gene was cloned and expressed as a soluble protein of 40 kDa, having optimal activity at pH 6.0 and 30 °C. EaChi40 showed good stability and high specific activity, and kinetic studies found K m and V max were 0.86 mg/mL and 13.66 μmol/min/mg. For conversion crayfish shell into oligosaccharides, ball milling and ultrasound-assisted hydrogen peroxide decolorization were applied to pretreat crayfish shell to facilitate its hydrolysis. After the enzymatic conversion, the hydrolysis products of chitobiose and N-acetyl-D-glucosamine were 9.09 mg/mL and 9.21 mg/mL, respectively. EaChi40 efficiently degraded crayfish with a high hydrolysis rate of 76.1%. It is expected to be a good candidate for the production of chitin oligosaccharides in the food and biological fields. [ABSTRACT FROM AUTHOR]

Metal–protein interaction for regulating the function and structure of proteins is of major interest. We demonstrate here that the addition of 9 μmol Mg 2+ per mg ovomucin resulted in a 2.0-fold increase in the adhesion capacity of ovomucin to New Disease Virus (NDV) using ELISA method. The hemagglutinin inhibition rate of 100 μg/mL ovomucin–Mg 2+ mixture (9 μmol Mg 2+ per mg ovomucin) to NDV increased to 55.61%, which is significantly higher than that of the pure ovomucin ( P < 0.01). Binding characteristics of ovomucin to Mg 2+ were then evident by fluorescence and FT-IR spectroscopy as well as dynamic light scattering (DLS) technology. Fluorescence and FT-IR spectroscopy results suggest that Mg 2+ prefers to interact with the carbohydrate moiety of ovomucin without significant changes in the secondary structure when Mg 2+ concentration is less than 9 μmol/mg ovomucin. When Mg 2+ increases to 16 μmol/mg ovomucin, it gives rise to changes in secondary structure, and forms a more compact configuration. This is supported by the hydrodynamic radius of ovomucin with and without Mg 2+ binding as examined by DLS. The Mg 2+ bound in regulating the structure and activity of ovomucin provided important insight into the effect of metal ions on ovomucin binding to pathogens. [ABSTRACT FROM AUTHOR]

The aim of this paper was to demonstrate a rapid and selective fluorescence-linked immunoassay method based on quantum dots as the fluorescent marker for the detection of Salmonella Enteritidis on eggshell. Highly-fluorescent and water-soluble CdTe quantum dots were prepared by using thioglycolic acid and 1-thioglycerol as ligands and were then conjugated with anti-Salmonella antibodies. As a result of specific interaction, Salmonella Enteritidis were specifically captured by bioconjugated CdTe quantum dots which led to the detection of a fluorescent signal. The bacterial cell images were obtained using fluorescence microscopy. Under optimal conditions, the quenched fluorescence intensity increased linearly with the log total count of Salmonella Enteritidis ranging from 3 × 102 to 3 × 107 CFU/mL within 1–2 h. The low detection limit was 1 × 102 CFU/mL without sample enrichment. This method was satisfactorily applied to the analysis of egg samples, which was demonstrated as a simple scheme for quick and selective detection of Salmonella Enteritidis on eggshell. [ABSTRACT FROM AUTHOR]

[Display omitted] • SEW improved the texture properties of steamed bread. • SEW is utilised as a sustainable ingredient in steamed bread formulations. • Micromorphology showed a compact and smooth structure after adding SEW. • Enrichment of steamed bread with 15% SEW shows significant acceptability. Steamed bread has long been an important part of Chinese cuisine. This study investigated the effects of salted egg white (SEW) (5, 10, 15, and 20% w/w) on the quality of steamed breads. Findings revealed that SEW notably enhanced the bread's volume and texture, with a 20% inclusion significantly boosting water retention and rheological properties, albeit reducing bread's lightness. In addition, the H-bond absorption band intensity in the Fourier transform infrared spectroscopy (FTIR) analysis showed increased peak intensities with higher SEW levels, indicative of protein structure alterations. X-ray diffraction confirmed the presence of an amylose–lipid complex. Scanning electron microscope (SEM) and Confocal laser scanning microscope (CLSM) imaging depicted a smooth, consistent protein network with SEW addition. Consumer sensory evaluation responded favourably to the SEW15 steamed bread, suggesting its potential for food industry application. Overall, the study considers SEW an effective ingredient for improving steamed bread quality. [ABSTRACT FROM AUTHOR]

This study prepared emulsion gels by modifying ovalbumin (OVA)-flaxseed oil (FSO) emulsions with transglutaminase (TGase) and investigated their properties, structure and oxidative stability under different enzyme reaction times. Here, we found prolonged reaction times led to the transformation of α-helix and β-turn into β-sheet and random coil. The elasticity, hardness and water retention of the emulsion gels increased significantly, but the water-holding capacity decreased when the reaction time exceeded 4 h. Confocal laser scanning microscope (CLSM) indicated extended enzyme reaction time fostered oil droplet aggregation with proteins. Emulsion gel reduced FSO oxidation, especially after 4 h of the enzyme reaction, the peroxide value (PV) of the emulsion gel was reduced by 29.16% compared to the control. In summary, the enzyme reaction time of 4 h resulted in the formation of a dense gel structure and enhanced oxidative stability. This study provides the potential applications in functional foods and biomedical fields. [Display omitted] • A novel FSO - encapsulated emulsion gel was constructed by inducing OVA with TGase. • Extended enzymatic reaction time improved emulsion gel properties and structure. • TGase - treated OVA aggregated more on the surface of the oil droplets. • Emulsion gel enhanced the oxidative stability of FSO during storage. [ABSTRACT FROM AUTHOR]

The foaming property of egg white (EW) is essential in food processing. In this study, we investigated the effect of ultrasound combined with adding different concentrations (0, 0.4, 0.5, 0.6, 0.7, and 0.8 %, m/v) of flaxseed gum (FG) on EW foaming. The results showed that the cooperation of ultrasound treatment and FG significantly improved the foaming stability. Regarding details, FG reduced the sulfhydryl content and surface hydrophobicity of EW proteins while increasing the average particle size and PDI value. Despite the ultrasound treatment, FG significantly improved the foaming stability from 62.83% to 99.82% (p < 0.05). Based on the analysis of ξ-potential, surface tension, rheology, etc., FG improved the EW microenvironment, which is conducive to foaming stability. As a new type of polysaccharide, FG combined with ultrasound can significantly improve the foaming properties. This research could solve the problem of reduced foaming stability of EW treated by ultrasound alone, making promising applications in the food industry. [Display omitted] • Ultrasound combined with flaxseed gum improved the foaming of egg white. • Flaxseed gum overcame the problem that ultrasound reducing the foaming stability. • Flaxseed gum formed a viscoelastic interfacial film to increase surface tension. • Egg white protein's structure was more compact and increased foaming stability. [ABSTRACT FROM AUTHOR]

Respiration plays a crucial role in the physiological development of embryos throughout the entire incubation process and serves as a vital indicator for discerning unfertilized eggs and embryos that have stopped development. This article explores the relationship between egg respiration, fertilization status, and chicken embryo viability. First, it studied the changes in respiration of fertilized and unfertilized eggs during the early stages of incubation (Day 1–3) and found that the CO 2 production of fertilized eggs gradually increased, while those of unfertilized eggs gradually decreased. Moreover, significant differences in respiration between fertilized and unfertilized eggs were observed on the second day of incubation. Next, we employed Random Forest (RF), Logistic Regression (LR), and Support Vector Machine (SVM) models to differentiate between fertilized and unfertilized eggs. Notably, the SVM algorithm exhibited exceptional performance in discriminating between fertilized and unfertilized eggs, achieving a remarkable test set accuracy of 98.41 %. Finally, a Bayesian algorithm was applied to classify embryos as either dead, weak, or viable in middle and later stages of incubation. Bayesian discriminant analysis yielded compelling results, achieving a 100 % detection rate for deceased embryo eggs. The outcomes of this study provide a robust theoretical foundation and empirical data to advance non-destructive testing methodologies for poultry eggs. Graphic abstract. [Display omitted] • Identification of weak and dead embryo based on respiration. • Respiration analysis of fertilized and unfertilized eggs. [ABSTRACT FROM AUTHOR]

Abstract: Purification of ovomucin is still an empirical technique and sometimes insufficient quantities of ovomucin are purified to allow characterization. Here we aimed to investigate the effect of MgCl2 on the purity and bioactivity of ovomucin during isoelectric precipitation process and to develop an effective protocol to prepare pure ovomucin with high bioactivity. It was found that addition of MgCl2 is an alternative approach to remove lysozyme from ovomucin, and that the hemagglutination inhibition (HI) activity of ovomucin with MgCl2 against New Disease Virus (NDV) was about two times higher than the protein without salts. Thus, an improved procedure comprises a precipitation with 0.05mol/L CaCl2 followed by precipitation with 0.05mol/L MgCl2 was developed for the isolation of ovomucin. Better adhesion property of ovomucin was observed when low concentration of MgCl2 was added in the designed ELASA test, whereas the adhesion property of the pure ovomucin without salts to NDV was lower. Thus, magnesium (II) plays an important role in the activity of ovomucin, and the alternative method developed in this study may significantly facilitate the further research on the mechanism of ovomucin activity. [Copyright &y& Elsevier]

• HPCD process affect liquid whole egg quality as well as disposal of sterilization. • HPCD process promoted interfacial properties of liquid whole egg. • The physicochemical properties of protein were changed by HPCD. • The apparent viscosity of LWE declined after HPCD treatment. In this research, the impact of High Pressure Carbon Dioxide (HPCD) on the physicochemical, interfacial and rheological properties of liquid whole egg (LWE) was investigated. HPCD treatment increased the solubility, free sulfhydryl groups and surface hydrophobicity of LWE. The highest foaming ability (186%) and foaming stability (72%) were obtained at 60 min of HPCD treatment, which were 1.3-fold and 1.4-fold those of the control group (147% and 51%, respectively). Compared with the control group, the LWE emulsion had a minimum particle size (16.3 μm) when the treatment time was 75 min, and the highest absolute value of zeta potential reached 7.66 mV when the processing time was 60 min. HPCD treatment decreased the apparent viscosity of LWE at a low shear rate. Dynamic viscoelastic characteristics indicated that both the G' and G" moduli of LWE under the HPCD process were lower than those of the control group at any frequency. [ABSTRACT FROM AUTHOR]

• The chitosan and eggshell membrane powder composite macroparticles were prepared. • The eggshell membrane powder increased the porosity of chitosan macroparticle. • The eggshell membrane powder improved the activity sites for enzyme immobilization. • The increase in pore size could improve the activity of immobilized protease. Chitosan-based macroparticle is a common carrier for enzyme immobilization applied in food industry. Driven by the requirement of large carrier pores for the biomacromolecular substrates such as protein, the eggshell membrane powder (ESMP) was employed as multifunctional porogen to improve the physicochemical structure of chitosan-based macroparticles. The prepared macroparticles were characterized by SEM, XRD, FTIR, Raman spectroscopy, nitrogen adsorption-desorption isotherms, and thermogravimetric analysis. The results showed that an increase of ESMP percentage could improve the porosity of macro holes in macroparticles, and it also enlarged the size of mesopores. Moreover, the ESMP significantly increased (P < 0.05) the amount of papain immobilization, whereas the specific activity of immobilized papain achieved a maximum value of 871.95 U/mg at CSESM2 and then declined with the increase of ESMP. Therefore, the inclusion of 20 % ESMP in chitosan-based macroparticles gave the highest activity of its immobilized protease. [ABSTRACT FROM AUTHOR]

Preserved egg, a traditional Chinese egg product, is regarded as an anti-inflammatory food in traditional Chinese medicine. This study was aimed to examine anti-inflammatory effect of the simulated gastrointestinal digestive products of whole preserved egg (DWPE), preserved egg white (DPEW), and preserved egg yolk (DPEY) on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results demonstrated that DWPE, DPEW, or DPEY inhibited the LPS-induced secretion of Nitric oxide (NO), without marked cytotoxicity. The DWPE, DPEW, and DPEY significantly suppressed the secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6. Particularly, the inhibition rate of DPEW on NO, IL-6, and TNF-α could reach 25 to 27%, 31 to 42%, and 26 to 38%, respectively (P < 0.05). Furthermore, the DPEW and DPEY downregulated the gene expression of Cyclooxygenase-2 and inducible nitric oxide synthase in a dose-dependent manner. Taken together, this study indicated that DWPE, DPEW, and DPEY, especially DPEW, might serve as functional food for anti-inflammatory therapy. [ABSTRACT FROM AUTHOR]

• Nano-TiO 2 has enhanced properties of the pullulan film. • The WVP value of film was obtained minimally at 6.6 × 10−4 g m/m2 h KPa. • The TS value of film was obtained maximally at 15.99 MPa. • The ability of the blend film to block UV has been significantly improved. In this study, effects of nano-TiO 2 on the microstructural, physical, mechanical and optical properties of pullulan films were investigated. The results showed that the addition of nano-TiO 2 improved the water vapor barrier properties of the film due to the tortuous path formed by nano-TiO 2. When the concentration of nano-TiO 2 was 0.04 g/100 mL, the tensile strength of the film showed a maximum value (15.99 MPa). The elongation at break of the film continued to decrease with the increase of nano-TiO 2. The TEM analysis showed that higher concentration of nano-TiO 2 would cause greater aggregation. Meanwhile, the results of FTIR and low-field NMR indicated that the miscibility between pullulan and nano-TiO 2 was due to the formation of intermolecular hydrogen bonds during film formation. Furthermore, the addition of nano-TiO 2 significantly improved the film barrier properties to ultraviolet light. [ABSTRACT FROM AUTHOR]