The effect of polysaccharide type on dielectric barrier discharge (DBD) plasma glycosylation of sodium caseinate-part I: Physicochemical, structural and thermal properties.

This study aimed to investigate the impact of polysaccharide type on the physicochemical, structural, and thermal properties of dielectric barrier discharge (DBD) plasma glycosylated sodium caseinate (SC). The polysaccharides Quince seed gum (QSG), carboxymethyl cellulose (CMC), and maltodextrin (MD) were mixed with SC and treated with DBD plasma at 18 kV for 10 min. The grafting degree, electrophoresis pattern, FTIR, XRD, carbonyl, sulfhydryl, and di-tyrosine content, FE-SEM, color, and thermal properties of SC and its polysaccharide mixtures before and after plasma treatment were analyzed. Results showed that the SC-QSG conjugate had the highest glycation degree and color change after plasma treatment. The SC-CMC and SC-QSG conjugates exhibited disappearance of distinct SC bands in electrophoresis pattern compared to SC. Also, significant changes in functional group and crystallinity were occurred in SC-CMC conjugate. Plasma treatment caused oxidation of SC, but the presence of polysaccharides offered protection against oxidation. The microstructure of SC was altered by mixing with polysaccharides and exposure to plasma. Also, the mixtures indicated higher thermal stability after plasma treatment. Results confirmed that the generation of protein-polysaccharide conjugates through DBD plasma technique was depended on with SC-MD conjugate unable to form through this method.

Protective effect of PCV13 against all-cause hospitalized pneumonia in children in Beijing, China: real-world evidence.

BACKGROUND: The study evaluated the protective effect of 13-valent pneumococcal polysaccharide conjugate vaccine (PCV13) against all-cause hospitalized pneumonia in children in Beijing. METHODS: Based on the vaccination record and inpatient medical record database of Beijing, children born in 2017 in Beijing, matched by age, gender, and district of the children with the ratio of 1:4, were selected as the vaccinated and unvaccinated groups according whether if vaccinated with PCV13. The incidence rate and 95 % confidence interval (95 %CI), vaccine effectiveness (VE) and direct medical costs of all-cause hospitalized pneumonia were calculated and compared within the same period of 12 months, 18 months, 24 months and 30 months after the birth of the child. RESULTS: The decreased incidence rates of all-cause hospitalized pneumonia were observed at the four points in the PCV13 vaccinated group compared to the unvaccinated group, which were significant at the points of 12 months (0.42 % vs. 0.72 %, P = 0.001), 18 months (0.90 % vs. 1.26 %, P = 0.002) and 24 months (1.37 % vs. 1.65 %, P = 0.046). The VE of PCV13 against all-cause hospitalized pneumonia within 12 months was the highest as 41.9 % (95 % CI 19.6 %, 58.0 %), followed by 29.3 % (95 % CI 11.4 %, 43.5 %) within 18 months, 17.1 % (95 % CI 0.3 %, 31.1 %) within 24 months and it almost disappeared within 30 months. The VE of 4-dose vaccination within 18 months and 24 months were 39.9 % (95 % CI 20.3 %, 54.7 %) and 27.2 % (95 % CI 8.6 %, 42.0 %), respectively. The median hospitalization cost of the children in the vaccinated group was higher at the four points but without significance. CONCLUSIONS: PCV13 had a certain protective effect on all-cause hospitalized pneumonia, and the booster immunization strategy had the best protective effect with great public health significance to enter the immunization program.

Post-marketing safety surveillance for both CRM197 and TT carrier proteins PCV13 in Jiangsu, China.

Background: This study is to evaluate the safety of two kinds of PCV13 carriers by monitoring the occurrence of adverse event following immunization (AEFI) after the launch of two kinds of PCV13 carriers in Jiangsu Province, China. Methods: The AEFI Information System (CNAEFIS) of mainland China was used to monitor the incidence and classification of adverse reactions of the CRM197-carrier protein PCV13 and TT-carrier protein PCV13 vaccines. Results: There was no statistical difference between the cumulative reported incidence of AEFI between the two vaccines from 2020 to 2022 (χ2 = 1.991, p < 0.158). 96.62% of the AEFIs were classified as common reactions; rare reactions and coincidental events only accounted for 2.99 and 0.39% of all the AEFI cases, respectively. Redness (2.6 cm-5 cm) is the commonest symptom at the injection site for both vaccines. More than 97% of AEFIs occurred between 30 min and 3 days after administration for both types of PCV13. Conclusion: Both vaccines perform well in terms of safety. We did not identify any new/unexpected safety concern from the NAEFISS during a 4 years timespan.

Reinforcing alginate matrixes by tea polysaccharide conjugates or their stabilized nanoemulsion for probiotics encapsulation: Characterization, survival after gastrointestinal digestion and ambient storage.

Tea polysaccharide conjugates (TPC) were used as fillers in the form of biopolymer or colloidal particles (TPC stabilized nanoemulsion, NE) for reinforcing alginate (ALG) beads to improve the probiotic viability. Results demonstrated that adding TPC or NE to ALG beads significantly enhanced the gastrointestinal viability of encapsulated probiotics when compared to free cells. Moreover, the survivability of free and ALG encapsulated probiotics markedly decreased to 2.03 ± 0.05 and 2.26 ± 0.24 log CFU/g, respectively, after 2 weeks ambient storage, indicating pure ALG encapsulation had no effective storage protective capability. However, adding TPC or NE could greatly enhance the ambient storage viability of probiotics, with ALG + NE beads possessing the best protection (8.93 ± 0.06 log CFU/g) due to their lower water activity and reduced porosity. These results suggest that TPC and NE reinforced ALG beads have the potential to encapsulate, protect and colonic delivery of probiotics.

Analysis of 13-valent pneumococcal polysaccharide conjugate vaccine among children born in Hangzhou from 2017 to 2021.

Background: 13-valent pneumococcal polysaccharide conjugate vaccine (PCV13) has been introduced in Hangzhou since 2017, whereas its current immunization state in children is not clear. Therefore, this study aims to describe the PCV13 vaccination distribution among children born in Hangzhou from 2017 to 2021 to provide data for reducing vaccination differences among different populations. Methods: Descriptive epidemiology was used for data analysis and PCV13 vaccination related information of children was collected from children vaccination management system of Zhejiang Province (ZJCVMS). Results: Among the 649,949 children born in Hangzhou from 2017 to 2021, 169,230 were vaccinated with an average full course vaccination rate of 26.0%. The full course vaccination rates in 5 years were different (P = 0.000) with an increasing trend (P fortrend < 0.01). The first dose vaccination rates were different in 5 years (P = 0.000) with an increasing trend (P fortrend < 0.01). The distribution of age when first dose PCV13 was administered varied, most people at 2 months and least people at 5 months. The full course vaccination rate varied by areas, highest in central urban areas and lowest in remote areas respectively (all P-value < 0.05). Overall, the full course vaccination rate of PCV13 was higher in the registered residence population than the non-registered residence population, which was 136,693 (31.4%) and 32,537 (15.1%) respectively (P = 0.000). The full course vaccination rates were the same between men and women (P = 0.502), which was 87,844 for men (26.0%) and 81,386 for women (26.1%). Conclusion: Although the number of people who received PCV13 full course vaccination and received the first dose vaccination showed yearly increasing trends in Hangzhou, the full course vaccination rate for the whole population was relatively low. In addition, the PCV13 vaccination rates also differed by geography and household registration status. Measures such as expanding vaccination publicity or including national immunization should be taken to increase vaccination rates and reduce the differences in vaccination among groups with different characteristics.

Regulating effects of phytosterol esters-loaded emulsions stabilized with green tea polysaccharide conjugates and Tween on lipids in KKAy mice.

Phytosterol esters (PSE) have been shown to have cholesterol-lowering effects, but their insolubility in water limits their applications. Green tea polysaccharide conjugates (gTPC) have hypoglycemic and emulsifying effects. To address lipid dysregulation in diabetic patients, we developed PSE-loaded emulsions stabilized with gTPC and Tween-20 (gTPC-PSE emulsions) and evaluated their physicochemical properties. We subsequently investigated the lipid-regulating potential of these emulsions to in KKAy mice. The KKAy mice were randomly assigned to eight groups: the model group, the Lipitor (10 mg·kg-1)-acarbose (30 mg·kg-1) combination group, two gTPC groups, two PSE groups, and two gTPC-PSE groups with a 1:2 mass ratio of gTPC to PSE. The administered doses were 90 and 270 mg kg-1, respectively. Administration of a 270 mg·kg-1 dose of gTPC-PSE emulsions led to the most significant effects including increased levels of liver and serum high-density lipoprotein cholesterol (HDL-CH), reduced serum leptin and insulin, and improved liver superoxide dismutase (SOD) and reduced malondialdehyde (MDA). In general, gTPC and PSE demonstrated a synergistic effect on lipid regulation in mice. Our results indicate that gTPC-PSE emulsions hold potential as a nutritional intervention for diabetes by modulating lipid levels.

Zeaxanthin Dipalmitate-Enriched Emulsion Stabilized with Whey Protein Isolate-Gum Arabic Maillard Conjugate Improves Gut Microbiota and Inflammation of Colitis Mice.

In the present study, protein-polysaccharide Maillard conjugates were used as novel emulsifiers and bioactive carriers. Effects and potential mechanisms of zeaxanthin dipalmitate (ZD)-enriched emulsion stabilized with whey protein isolate (WPI)-gum Arabic (GA) conjugate (WPI-GA-ZD) and ZD-free emulsion (WPI-GA) on gut microbiota and inflammation were investigated using a model of dextran sulfate sodium (DSS)-induced colitis in mice. As a result, supplementation with WPI-GA and WPI-GA-ZD improved the serum physiological and biochemical indicators, decreased the expression of pro-inflammatory cytokines and related mRNA, as well as increased the tight junction proteins to a certain extent. 16S rDNA sequencing analyses showed that supplementation with WPI-GA and WPI-GA-ZD presented differential modulation of gut microbiota and played regulatory roles in different metabolic pathways to promote health. Compared with WPI-GA, the relative abundances of Akkermansia, Lactobacillus and Clostridium_IV genera were enriched by the intervention of WPI-GA-ZD. Overall, the designed carotenoid-enriched emulsion stabilized with protein-polysaccharide conjugates showed potential roles in promoting health.

Gellan gum conjugation with soy protein via Maillard-driven molecular interactions and subsequent clustering lead to conjugates with tuned technological functionality.

Soy proteins are frequently used in the food industry; however, they have rigid and compact structure with relatively poor interfacial properties and solubility. This study was therefore aimed to modify techno-functional characteristics of soy protein isolate (SPI; 0.1% w/v) by conjugating to low acyl gellan gum (LAGG; 0.1, 0.2, and 0.3% w/v), through the Maillard reaction (at 90 °C for 90 min). The SPI-LAGG conjugates were confirmed by changes in pH, glycation degree (DG; up to 48%), Fourier transform infrared spectroscopy, and sodium dodecyl sulphate polyacrylamide electrophoresis. The conjugates were then classified into three clusters of low, medium, and high DG, via K-means clustering method. The low DG conjugate had lower surface hydrophobicity and foaming capacity, and higher thermal stability, solubility, emulsifying properties, foam stability, and antioxidant activity compared to the other clusters. This indicated that a low DG is required to enhance the functional properties of proteins.

A phase II, single-center, randomized, double-blind, parallel control clinical study evaluating the immunogenicity and safety of a two-dose schedule of serogroups ACYW meningococcal polysaccharide conjugate vaccine.

BACKGROUND: This was a single-center, randomized, double-blind, parallel control study evaluating the immunogenicity and safety of a two-dose schedule of serogroups ACYW meningococcal polysaccharide conjugate vaccine with tetanus toxoid (TT) conjugate protein, in infants and toddlers of 3-35 months old. METHOD: 720 participants were stratified according to the age of 3-5 months old, 6-11 months old, and 12-35 months old and randomly assigned with an equal ratio to two different dose groups, i.e., 40- and 20-µg doses. Blood samples were taken from all participants before the first vaccination and 30 days after the full-course vaccination to detect the serogroups ACYW meningococcal antibodies. All adverse events occurred within 30 days after vaccination of each dose, and serious adverse events occurred within six months after full-course vaccination were collected for safety evaluation. This study was registered at the China drug trial registration with the identifier CTR 20182031. RESULTS: After 30 days of full-course vaccination, 92.78 % (95 % CI: 85.70 %-100.00 %) showed the immune response against all serogroups in both high-dose and low-dose groups by rabbit serum bactericidal antibody assay (rSBA) and the geometric mean titer (GMT) of all serogroups showed a high level (74.6-505.8, 95 % CI: 56.4-615.7). However, no significant difference between different dose groups was observed (P > 0.05). The common local and systemic adverse events in both groups were redness (3 %-7%), and fever (26 %-65 %), respectively. In addition, the grade 3 adverse event related to the vaccine was fever (1.67 %-12.50 %). No serious adverse event was reported to be associate with the vaccination. CONCLUSION: The serogroups ACYW meningococcal polysaccharide conjugate vaccine was safe and effective in the population aged 3-35 months. The vaccine efficacy and safety of the 20-µg dose group were not less than that of the 40-µg dose group.

The remarkable history of pneumococcal vaccination: an ongoing challenge.

Although it varies with age and geographical distribution, the global burden of infection with Streptococcus pneumoniae (pneumococcus) remains considerable. The elderly, and younger adults with comorbid conditions, are at particularly high risk of pneumococcal infection, and this risk will increase as the population ages. Vaccination should be the backbone of our current strategies to deal with this infection.Main body: This manuscript reviews the history of the development of pneumococcal vaccines, and the impact of different vaccines and vaccination strategies over the past 111 years. It documents the early years of vaccine development in the gold mines of South Africa, when vaccination with killed pneumococci was shown to be effective, even before the recognition that different pneumococci were antigenically distinct. The development of type-specific vaccines, still with whole killed pneumococci, showed a high degree of efficacy. The identification of the importance of the pneumococcal capsule heralded the era of vaccination with capsular polysaccharides, although with the advent of penicillin, interest in pneumococcal vaccine development waned. The efforts of Austrian and his colleagues, who documented that despite penicillin therapy, patients still died from pneumococcal infection in the first 96 h, ultimately led to the licensing first of a 14-valent pneumococcal polysaccharide in 1977 followed by the 23-valent pneumococcal polysaccharide in 1983. The principal problem with these, as with other polysaccharide vaccines, was that that they failed to immunize infants and toddlers, who were at highest risk for pneumococcal disease. This was overcome by chemical linking or conjugation of the polysaccharide molecules to an immunogenic carrier protein. Thus began the era of pneumococcal conjugate vaccine (PCV), starting with PCV7, progressing to PCV10 and PCV13, and, most recently, PCV15 and PCV20. However, these vaccines remain serotype specific, posing the challenge of new serotypes replacing vaccine types. Current research addresses serotype-independent vaccines which, so far, has been a challenging and elusive endeavor.Conclusion: While there has been enormous progress in the development of pneumococcal vaccines during the past century, attempts to develop a vaccine that will retain its efficacy for most pneumococcal serotypes are ongoing.

Development of Millettia speciosa champ polysaccharide conjugate stabilized oil-in-water emulsion for oral delivery of ß-carotene: Protection effect and in vitro digestion fate.

In this study, a natural antioxidant emulsifier, Millettia speciosa Champ polysaccharide conjugates (MSC-PC), was used for fabricating oil-in-water emulsion, and the influences of MSC-PC on ß-carotene stability and bioaccessibility were studied. Results suggested that MSC-PC stabilized emulsion exhibited excellent resistance to a wide range of salt levels (0-500 mM of Na+), thermal treatments (50-90 °C) and pH values (3.0-11.0). MSC-PC also exhibited an outstanding inhibition capacity on lipid oxidation. Besides, MSC-PC stabilized emulsion had a better protective effect on ß-carotene than other systems. Interestingly, in spite of similar lipolysis extent, ß-carotene bioaccessibility in MSC-PC fabricated emulsion (14.75 %) was markedly higher than that in commercial Tween 80 fabricated emulsion (10.08 %), likely due to the steric-hindrance effect and antioxidant ability of MSC-PC, building interfacial layers that prevented ß-carotene from degradation. This work supplied a deep insight into elucidating the mechanisms of emulsifying performance and ß-carotene protection effect of MSC-PC fabricated emulsion.

Streptococcus pneumoniae serotype 15B polysaccharide conjugate elicits a cross-functional immune response against serotype 15C but not 15A.

Protection conferred by pneumococcal polysaccharide conjugate vaccines (PCVs) is associated with PCV-induced antibodies against vaccine-covered serotypes that exhibit functional opsonophagocytic activity (OPA). Structural similarity between capsular polysaccharides of closely related serotypes may result in induction of cross-reactive antibodies with or without a cross-functional activity against a serotype not covered by a PCV, with the former providing an additional protective clinical benefit. Serotypes 15B, 15A, and 15C, in the serogroup 15, are among the most prevalent Streptococcus pneumoniae serotypes associated with invasive pneumococcal disease following the implementation of a 13-valent PCV; in addition, 15B contributes significantly to acute otitis media. Serological discrimination between closely related serotypes such as 15B and 15C is complicated; here, we implemented an algorithm to quickly differentiate 15B from its closely related serotypes 15C and 15A directly from whole-genome sequencing data. In addition, molecular dynamics simulations of serotypes 15A, 15B, and 15C polysaccharides demonstrated that while 15B and 15C polysaccharides assume rigid branched conformation, 15A polysaccharide assumes a flexible linear conformation. A serotype 15B conjugate, included in a 20-valent PCV (PCV20), induced cross-functional OPA serum antibody responses against the structurally similar serotype 15C but not against serotype 15A, both not included in PCV20. In PCV20-vaccinated adults (18-49 years), robust OPA antibody titers were detected against both serotypes 15B (the geometric mean titer [GMT] of 19,334) and 15C (GMTs of 1692 and 2747 for strains PFE344340 and PFE1160, respectively), but were negligible against serotype 15A (GMTs of 10 and 30 for strains PFE593551 and PFE647449, respectively). Cross-functional 15B/C responses were also confirmed using sera from a larger group of older adults (60-64 years).

Conjugate of structurally reassigned pneumococcal serotype 31 polysaccharide with CRM197 elicited potent immune response.

Around 100 Streptococcus pneumonia (Spn) serotypes have been discovered, 90% of the severe diseases in children are caused by 13 serotypes. With the success of pneumococcal bacterial polysaccharide conjugate vaccines (PCVs), the burden of pneumococcal disease has been significantly reduced. Serotype 31 is a non-vaccine serotype and has increased in prevalence. By using Nuclear Magnetic Resonance (NMR) as the primary tool, we report the revised serotype 31 polysaccharide (s-31-ps) structure as [→3)-ß-D-Galf-(5/6-OAc)-(1 â†’ 3)-ß-D-Galp-(1 â†’ 3)-ß-L-Rhap-(2-OAc)-(1 â†’ 2)-α-L-Rhap-(1 â†’ 4)-ß-D-GlcpA-(1→]n. Furthermore, the reductive amination-conjugate of serotype 31 polysaccharide and cross reacting material (CRM197) protein was prepared in organic solvent (N,N-dimethylformamide, DMF) instead of water. The reaction is faster, and the DMF conjugate elicited comparable immune responses with the aqueous conjugate. S-31-ps conjugate vaccine has the potential of being included in the next-generation PCV vaccines.

Advances towards licensure of a maternal vaccine for the prevention of invasive group B streptococcus disease in infants: a discussion of different approaches.

Group B streptococcus (Streptococcus agalactiae, GBS) is an important cause of life-threatening disease in newborns. Pregnant women colonized with GBS can transmit the bacteria to the developing fetus, as well as to their neonates during or after delivery where infection can lead to sepsis, meningitis, pneumonia, or/and death. While intrapartum antibiotic prophylaxis (IAP) is the standard of care for prevention of invasive GBS disease in some countries, even in such settings a substantial residual burden of disease remains. A GBS vaccine administered during pregnancy could potentially address this important unmet medical need and provide an adjunct or alternative to IAP for the prevention of invasive GBS disease in neonates. A hurdle for vaccine development has been relatively low disease rates making efficacy studies difficult. Given the well-accepted inverse relationship between anti-GBS capsular polysaccharide antibody titers at birth and risk of disease, licensure using serological criteria as a surrogate biomarker represents a promising approach to accelerate the availability of a GBS vaccine.

Immunogenicity of meningococcal polysaccharide conjugate vaccine as a replacement for meningococcal polysaccharide vaccine in children in Guangzhou, China.

To assess the durability of antibody persistence after substitution of the MPCV vaccine for the MPSV-A vaccine in children, an observational study was conducted in children who voluntarily received two doses of MPCV-AC instead of MPSV-A between March 2017 and March 2018 in Guangzhou, China. In total, 131 and 47 participants were enrolled in the 3-year-old and 6-year-old groups, respectively. In the 3-year-old group, the seroprotection rate and GMT values for Men A and Men C were raised significantly after 1-month post- dose 1 MPSV booster vaccination. All immune indicators were significantly lower in pre- dose 1 MPSV booster vaccination in the 3-year-old group than after pre- dose 2 MPSV booster vaccination in the 6-year-old group. While no significant differences were found in most immune indicators between the 1-month post- dose 1 MPSV booster vaccination in the 3-year-old group and pre- dose 2 MPSV booster vaccination in 6-year-old group. The substitute meningococcal immunization schedule showed a good immunogenicity in young children, and good sequential immunogenicity with MPSV booster immunization.

Enzymatic synthesis, characterization and properties of the protein-polysaccharide conjugate: A review.

Poor solubility of proteins negatively affects their functional properties and greatly limits their application. Enzymatic cross-linking with polysaccharides can improve solubility and functional properties of proteins. The enzymes used include transglutaminase, laccase and peroxidase. Therefore, this work introduces the cross-linking mechanisms of these enzymes and the characterization techniques, the improved properties and the potential applications of the enzymatically-synthesized protein-polysaccharide conjugate. Transglutaminase catalyzes the formation of a new peptide bond and thus works on amino-containing polysaccharides to conjugate with proteins. However, laccase and peroxidase catalyze oxidation of various compounds with phenol and aniline structures. Therefore, these two enzymes can catalyze the conjugate reaction between proteins and feruloylated polysaccharides which are widely distributed in cereal bran. Compared with the unmodified protein, the enzymatically-synthesized protein-polysaccharide conjugate usually has higher solubility and better functional properties. Thus, it is inferred that enzymatic conjugation with polysaccharide molecules can extend the application of proteins.

Novel Pneumococcal Protein-Polysaccharide Conjugate Vaccine Based on Biotin-Streptavidin.

Pneumococcal disease is a serious public health problem worldwide and an important cause of morbidity and mortality among children and adults in developing countries. Although vaccination is among the most effective approaches to prevent and control pneumococcal diseases, approved vaccines have limited protective effects. We developed a pneumococcal protein-polysaccharide conjugate vaccine that is mediated by the noncovalent interaction between biotin and streptavidin. Biotinylated type IV capsular polysaccharide was incubated with a fusion protein containing core streptavidin and Streptococcus pneumoniae virulence protein and relied on the noncovalent interaction between biotin and streptavidin to prepare the protein-polysaccharide conjugate vaccine. Analysis of vaccine efficacy revealed that mice immunized with the protein-polysaccharide conjugate vaccine produced antibodies with high potency against virulence proteins and polysaccharide antigens and were able to induce Th1 and Th17 responses. The antibodies identified using an opsonophagocytic assay were capable of activating the complement system and promoting pathogen elimination by phagocytes. Additionally, mice immunized with the protein-polysaccharide conjugate vaccine and then infected with a lethal dose of Streptococcus pneumoniae demonstrated induced protective immunity. The data indicated that the pneumococcal protein-polysaccharide (biotin-streptavidin) conjugate vaccine demonstrated broad-spectrum activity applicable to a wide range of people and ease of direct coupling between protein and polysaccharide. These findings provide further evidence for the application of biotin-streptavidin in S. pneumoniae vaccines.

Glycation of Plant Proteins Via Maillard Reaction: Reaction Chemistry, Technofunctional Properties, and Potential Food Application.

Plant proteins are being considered to become the most important protein source of the future, and to do so, they must be able to replace the animal-derived proteins currently in use as techno-functional food ingredients. This poses challenges because plant proteins are oftentimes storage proteins with a high molecular weight and low water solubility. One promising approach to overcome these limitations is the glycation of plant proteins. The covalent bonding between the proteins and different carbohydrates created via the initial stage of the Maillard reaction can improve the techno-functional characteristics of these proteins without the involvement of potentially toxic chemicals. However, compared to studies with animal-derived proteins, glycation studies on plant proteins are currently still underrepresented in literature. This review provides an overview of the existing studies on the glycation of the major groups of plant proteins with different carbohydrates using different preparation methods. Emphasis is put on the reaction conditions used for glycation as well as the modifications to physicochemical properties and techno-functionality. Different applications of these glycated plant proteins in emulsions, foams, films, and encapsulation systems are introduced. Another focus lies on the reaction chemistry of the Maillard reaction and ways to harness it for controlled glycation and to limit the formation of undesired advanced glycation products. Finally, challenges related to the controlled glycation of plant proteins to improve their properties are discussed.

Physicochemical stability and gastrointestinal fate of ß-carotene-loaded oil-in-water emulsions stabilized by whey protein isolate-low acyl gellan gum conjugates.

This study aimed to examine the effect of whey protein isolate-low acyl gellan gum (WPI-GG) conjugate on the physicochemical properties and digestibility of ß-carotene-loaded oil-in-water emulsions. The WPI-GG conjugate-stabilized emulsions had lower droplet sizes with more homogenous distribution, more negative surface charge, and higher interfacial protein concentration and viscosity, compared to those stabilized by WPI-GG mixture and WPI. The emulsion droplets coated by the conjugate were also generally more stable to environmental stresses (i.e., storage, pH changes, ionic strength, freeze-thaw cycles, and thermal treatment) along with higher ß-carotene retention than other systems. The stability to droplet aggregation during in vitro digestion was remarkably increased for the conjugate-stabilized emulsion. However, the ß-carotene bioaccessibility was significantly affected when the conjugate was used to stabilize the emulsions, likely due to the thick interfacial layer, high viscosity, and negative charge of the corresponding emulsions that could inhibit droplet digestion and mixed micelle formation.

Polyphenolic-polysaccharide conjugates from medicinal plants of Rosaceae/Asteraceae family protect human lymphocytes but not myeloid leukemia K562 cells against radiation-induced death.

The aim of the study was to investigate whether the polyphenolic-polysaccharide conjugates (PPCs), isolated from flowers of Sanguisorba officinalis L. and Erigeron canadensis L., and from leaves of Fragaria vesca L. and Rubus plicatus Whe. Et N. E., can protect human peripheral blood mononuclear cells (PBMCs) against gamma-irradiation damage while maintaining the radiosensitivity of the myeloid leukemia K562 cell line. PPCs isolated from the four plant sources are water-soluble macromolecules (14-50 kDa) that were previously chemically and structurally characterized. Cells were incubated with PPCs (25 µg/ml, 1 h) prior exposure to 15 Gy gamma-irradiation, non-irradiated appropriate samples served as controls. It was found that the PPCs were able to increase the post-radiation viability of PBMCs by inhibiting apoptosis, while they did not protect the leukemic cells against radiation-induced apoptotic death. The PPCs offered an efficient protection of PBMCs through scavenging of intracellular ROS and decreasing DNA damage, while they provided no reduction of the oxidative stress and DNA damage in K562 cells. Our findings strongly suggest that the PPCs, especially these isolated from S. officinalis and E. canadensis, can selectively protect normal lymphocytes against radiation injury, therefore they meet the criteria of radioprotectors for potential use in radiotherapy.