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This study investigated cellobionate production from a lignocellulosic substrate using Neurospora crassa HL10. Utilizing NaOH-pretreated wheat straw as the substrate obviated the need for an exogenous redox mediator addition, as lignin contained in the pretreated wheat served as a natural mediator. The low laccase production by N. crassa HL10 on pretreated wheat straw caused slow cellobionate production, and exogenous laccase addition accelerated the process. Cycloheximide induced substantial laccase production in N. crassa HL10, enabling the strain to yield approximately 57 mM cellobionate from pretreated wheat straw (equivalent to 20 g/L cellulose), shortening the conversion time from 8 to 6 days. About 92% of the cellulose contained in the pretreated wheat straw is converted to cellobionate. In contrast to existing methods requiring pure cellobiose or cellulase enzymes, this process efficiently converts a low-cost feedstock into cellobionate at a high yield without enzyme or redox mediator supplementation.

BACKGROUND: Sepsis-associated destruction of the pulmonary microvascular endothelial glycocalyx (EGCX) creates a vulnerable endothelial surface, contributing to the development of acute respiratory distress syndrome (ARDS). Constituents of the EGCX shed into circulation, glycosaminoglycans and proteoglycans, may serve as biomarkers of endothelial dysfunction. We sought to define the patterns of plasma EGCX degradation products in children with sepsis-associated pediatric ARDS (PARDS), and test their association with clinical outcomes. METHODS: We retrospectively analyzed a prospective cohort (2018-2020) of children (≥1 month to 60% of the severe PARDS patients (test for trend, p = 0.04). Higher total heparan sulfate and N-sulfated disaccharide levels were independently associated with fewer 28-day ventilator-free days in children with sepsis-associated PARDS (all p

The subtle structural variations among carbohydrate isomers pose significant challenges for their identification and quantification. Here, we propose a strategy for rapid identification and quantification of isomeric disaccharides via derivatization with 4-(3-methyl-5-oxo-pyrazolin-1-yl) benzoic acid (CPMP) and analysing by ion mobility spectrometry (IMS). After derivatization, the ionization efficiency of disaccharides was significantly improved. The disaccharide isomers were distinguished by determining the different ion mobilities of CPMP-labelled disaccharides. Among them, [M + 2CPMP + H]+ was separated with a resolution of 1.484, almost achieving baseline separation. Subsequently, [M + CPMP + Na]+ was used for the relative quantification of lactose and maltose, showing a good linear relationship with R2 > 0.990. Finally, the method was successfully applied to the identification of lactose and maltose in beer and milk. The method is fast, accurate and effective for the identification of disaccharide isomers in complex samples. [ABSTRACT FROM AUTHOR]

Synthesis of Galβ1 → 3GlcNAc-repeating saccharides is limited mainly by the formation of less-reactive oxazolines. We herein report an expeditious approach that requires trichloroacetyloxazolines as reactive glycosyl donors. Using only two disaccharide building blocks, the iterative oxazoline formation and glycosylation synthesized hexa- and octasaccharides with overall yields of 47% and 26% in four and six steps, respectively. [ABSTRACT FROM AUTHOR]

A divergent synthetic route to chondroitin sulfate (CS) disaccharide precursors, including rarer subtypes such as CS−D, has been developed. From common intermediates, a series of thioglycoside D‐glucosyl donors and 4,6‐O‐benzylidene protected D‐galactosamine acceptors are utilised in a robust glycosylation reaction, achieving β‐selectivity and consistent yields (60–75 %) on scales >2.0 g. A post‐glycosylation oxidation to D‐glucuronic acid and orthogonal protecting groups delivers access to CS−A, CS−C, CS−D, CS−E and CS−O precursor subtypes. Of further note is a 4‐O‐benzyl regioselective reductive ring opening of a 4,6‐O‐benzylidene protected disaccharide using dichlorophenylborane (PhBCl2) and triethylsilane (Et3SiH) to access a CS−D precursor, in 73 % yield over two steps. Finally, synthesis of a 6‐O‐sulfated CS−C disaccharide containing a conjugable anomeric allyl tether is completed. These materials will provide a benchmark to further synthesise and study chondroitin sulfates. [ABSTRACT FROM AUTHOR]

Lipophosphoglycans (LPGs) are found on the surface of Leishmania, a protozoan parasite, and are immunologically important. Herein, disaccharide 1‐phosphate repeating units of LPGs were successfully synthesized on a solid support with high anomeric purity using a disaccharide α‐1‐phosphoramidite building block. To enhance solubility in the reaction solvent, hydroxy‐protecting groups in the form of para‐t‐butylbenzoyl were introduced to the building block. The saccharide chain was elongated via stable glycosyl boranophosphate linkages, followed by the conversion of inter‐sugar linkages to phosphodiester counterparts using an oxaziridine derivative. The addition of a silylating reagent post‐reaction with the oxaziridine derivative efficiently facilitated the conversion of boranophosohodiesters to phosphodiesters. This method enabled the α‐selective synthesis of up to 15 repeating units, marking the longest homogeneous repeating units of LPGs synthesized chemically. Given the chain length equivalence to native LPGs, the method developed herein holds promise for advancing anti‐Leishmanial pharmaceuticals and vaccines. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion The implementation of the fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet for irritable bowel syndrome (IBS) can be effectively delivered by dietitians in group settings. The initial FODMAP restriction phase is recommended to be followed for 4 weeks; however, limited efficacy data exist for 4‐week FODMAP restriction in group education clinical practice.We aimed to compare 4‐week versus 8‐week FODMAP group treatment pathways on clinical outcomes using a prospective service evaluation design of IBS patients attending FODMAP restriction (baseline) and reintroduction (follow‐up) group sessions (between 2015 and 2019). Clinical outcomes included global symptom question (GSQ) measuring satisfactory relief, gastrointestinal symptom rating scale (GSRS), stool frequency (SF), stool consistency using Bristol stool form scale (BSFS), diet acceptability, patient satisfaction with group sessions and dietary adherence. Logistic regression was used to test for differences in treatment effects when clinical outcomes were compared between groups.Patients (n = 284) included were aged 18 to 86 years (mean ± SD [standard deviation], 44.6 ± 15.5), 80% female, and were split into 4‐week (41%, 117/284) versus 8‐week (59%, 167/284) pathways with no differences in baseline characteristics. Mean ± SD time gap between baseline and follow‐up was 4.6 ± 0.9 weeks in the 4‐week pathway and 9.6 ± 3.3 weeks in the 8‐week pathway. When groups were compared at follow‐up, no statistical differences were observed in any measures (GSQ, GSRS, SF, BSFS, dietary adherence, diet acceptability and patient satisfaction).A 4‐week dietitian‐led group FODMAP treatment pathway is as clinically effective and maintains patient acceptability when compared to 8‐weeks and should be considered as part of routine clinical practice. [ABSTRACT FROM AUTHOR]

Knölker complexes have been recently used to perform the catalytic C1‐oxidation of unprotected sugars into sugar lactones. This oxidation method remained limited by the stability of the catalyst with the polyhydroxylated substrates. Our objective is now to overcome these limitations and extend this method to more challenging substrates such as disaccharides. We proposed in this paper two original designs of Knölker‐type complexes conceived to promote secondary H‐bond interactions with the OH groups of the substrates to stabilise the system and favour the transformation. In total, 8 novel pre‐catalysts were synthesised, fully characterised and applied in the anomeric oxidation of several sugar derivatives. Two of these new complexes proved to be more efficient than the Knölker complex for the oxidation of disaccharides. Moreover, a preliminary DFT study revealed the presence of H‐bonds interactions between the substrate and the oxygen atom on the ligand arm of the best complexes suggesting a beneficial role of this heteroatom on the catalytic efficiency. [ABSTRACT FROM AUTHOR]

There has been recent interest in using the β-galactosidase of Bacillus circulans to produce prebiotic oligosaccharides, including galactooligosaccharides (GOS), lactulose and lactosucrose. The types and amounts of the transgalactosylation products produced depend on the selectivities of the enzyme for the various transgalactosylation and hydrolysis reactions that occur. To date, the selectivities of the β-galactosidase of B. circulans for these reactions have not been adequately characterized. In the current work, we undertake four case studies using literature data for systems in which different product mixtures are produced (i) GOS; (ii) GOS and disaccharides; (iii) GOS and lactulose; and (iv) GOS and lactosucrose. We analyze this data to obtain quantitative estimates of the relevant selectivities. We show that, in the production of GOS, the isoform β-Gal-A is significantly less selective against hydrolysis reactions than the other β-galactosidase isoforms. In the production of lactulose, the β-galactosidase of B. circulans gives high lactulose yields, despite having a 19- to 33-fold preference for producing GOS over lactulose. In the production of lactosucrose, the β-galactosidase of B. circulans also prefers to produce GOS. [Display omitted] • β-galactosidase of B. circulans characterized in four transglycosylation processes. • Isoform β-Gal-A less selective against 1° and 2° hydrolysis than other isoforms. • High lactulose yields, despite preference for producing galactooligosaccharides. • Enzyme prefers producing galactooligosaccharides over lactosucrose. • Method for estimating selectivities unaffected by inhibition or denaturation. [ABSTRACT FROM AUTHOR]

The bacterium Vibrio vulnificus can cause severe infections internally and externally. The mortality rate of V. vulnificus -associated gangrene and septicemia has increased due to antibiotic resistance and the absence of human vaccine. Bacterial carbohydrates have been widely used in the development of bacterial vaccines. Here, a rare l -Gal p NAmA-containing disaccharide that exists in V. vulnificus biotype 2 serovar A O-antigen was synthesized from d -glucose and l -galactose. An investigation on the influence of different linkers on the disaccharide synthetic efficiency indicated that the amine linker has more practicality. Two α-glycosidic linkages were constructed with good stereoselectivity by using nonparticipating C2 azido group and solvent effect. An orthogonal protection strategy allowed introductions of carboxyl and acetamidino (Am) groups at the disaccharide stage. The synthesis of the amine-linked disaccharide will provide a basis for the preparation of the trisaccharide repeating unit and longer fragments of V. vulnificus biotype 2 serovar A O-antigen, as well as other complex glycans. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: N,N,N‐Trimethyl‐D‐glucosamine (TMG)‐chitotriomycin, a naturally occurring chitin related oligosaccharide, is a specific β‐N‐acetylhexosaminidases (HexNAcases) inhibitor for insects and fungi. Although TMG‐chitoriomycin holds great promise as a novel class insecticide and fungicide, the limited accessibility of TMG‐chitotriomycin prevents its further biological evaluation. We report herein a simple and eco‐friendly chemoenzymatic approach for the efficient synthesis of TMG‐chitotriomycin and its analogues. In this strategy, the readily available chitosan was enzymatically hydrolyzed and chemically N‐acetylated to afford the chitooligosaccharides ranging from disaccharide to hexasaccharide. These chitooligosaccharides were selectively deacetylated by two different chitin deacetylases followed by chemical N‐trimethylation to obtain the desired TMG‐chitotriomycin and a total of 13 TMG‐chitotriomycin analogues in the longest linear sequence of 4 steps in over 12% total yields. [ABSTRACT FROM AUTHOR]

We present a practical and convergent synthesis of glycoalkaloids solasonine 1 and its saponin derivative 2, incorporating a {3-O-α- L -rhamnopyranosyl-(1→2)-O-[β- D -glucopyranosyl-(1→3)]-β- D -galactopyranoside} moiety. The key features of this strategy include the following: (1) AuCl3–tBuCN cooperative catalysis enabling 1,2-trans stereoselective glycosidation of 2-branched trisaccharide trichloroacetimidate donors with steroidal aglycons, in the absence of neighboring group participation; (2) "cyanide effect" mediated regioselective benzoylation of the 4- and 6-hydroxyl groups of galactopyranosyl disaccharide; and (3) an effective approach to prevent orthoester byproduct formation. [ABSTRACT FROM AUTHOR]

Intestinal digestion and absorption are complex processes; thus, it is a challenge to imitate them realistically. There are numerous approaches available, with different disadvantages and advantages. The simplest methods to mimic absorption are the non-cell-based transport models but these lack important characteristics of enterocytes of the intestine. Therefore, the most often used method is to measure absorption through viable mammalian cells (most commonly Caco-2 cells, cultured on membrane insert plates), which not only assures the incorporation of brush border enzymes (responsible for the final digestion of peptides and disaccharides), it also simulates the absorption process. This means that influx/efflux transporter-facilitated transport, carrier-mediated transport, endocytosis, and transcytosis is also imitated besides passive diffusion. Still, these also lack the complexity of intestinal epithelium. Organoids or ex vivo models are a better approach if we want to attain precision but the highest accuracy can be achieved with microfluidic systems (gut-on-a-chip models). We propose that more research is necessary, and food absorption should also be studied on gut-on-a-chips, especially with fragmented organoids. Our review supports the choices of a proper intestinal epithelium model, which may have a key role in functional food development, nutrition studies, and toxicity assessment. [ABSTRACT FROM AUTHOR]

Development of elegant, selective, and efficient strategies for the production of value‐added platform chemicals from renewable feedstocks are in high demand to achieve the future needs and sustainable goals. In this context, an efficient acid‐promoted synthesis of highly valuable hydroxymethylfurfural (HMF) has been demonstrated from glucose, a major constituent of lignocellulosic biomass. The major challenge in the conversion of glucose to HMF is the selective isomerization of glucose to ketose, which in the present work has been successfully addressed through the amine‐mediated rearrangement of glucose to aminofructose under Amadori rearrangement. Importantly, subsequent dehydration step affords HMF and regenerates the amine employed in the first step, which could be readily recovered. In addition, scale‐up and successful integration into one‐pot synthesis of HMF proves the efficiency and applicability of the present transformation in large scale application. In addition, the method was also successfully extended to other monosaccharides and disaccharides to produce HMF. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Personalized management strategies are pivotal in addressing irritable bowel syndrome (IBS). This multicenter randomized controlled trial focuses on comparing the efficacy of a microbiome-based artificial intelligence-assisted personalized diet (PD) with a low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet (FODMAP) for IBS management. METHODS: One hundred twenty-one patients participated, with 70 assigned to the PD group and 51 to the FODMAP diet group. IBS subtypes, demographics, symptom severity (IBS-SSS), anxiety, depression, and quality of life (IBS-QOL) were evaluated. Both interventions spanned 6 weeks. The trial's primary outcome was the within-individual difference in IBS-SSS compared between intervention groups. RESULTS: For the primary outcome, there was a change in IBS-SSS of -112.7 for those in the PD group vs -99.9 for those in the FODMAP diet group (P = 0.29). Significant improvement occurred in IBS-SSS scores (P < 0.001), frequency (P < 0.001), abdominal distension (P < 0.001), and life interference (P < 0.001) in both groups. In addition, there were significant improvements in anxiety levels and IBS-QOL scores for both groups (P < 0.001). Importantly, PD was effective in reducing IBS SSS scores across all IBS subtypes IBS-Constipation (IBS-C; P < 0.001), IBS-Diarrhea (IBS-D; P = 0.01), and IBS-Mixed (IBS-M; P < 0.001) while FODMAP diet exhibited comparable improvements in IBS-C (P = 0.004) and IBS-M (P < 0.001). PD intervention significantly improved IBS-QOL scores for all subtypes (IBS-C [P < 0.001], IBS-D [P < 0.001], and IBS-M [P = 0.008]) while the FODMAP diet did so for the IBS-C (P = 0.004) and IBS-D (P = 0.022). Notably, PD intervention led to significant microbiome diversity shifts (P < 0.05) and taxa alterations compared with FODMAP diet. DISCUSSION: The artificial intelligence-assisted PD emerges as a promising approach for comprehensive IBS management. With its ability to address individual variation, the PD approach demonstrates significant symptom relief, enhanced QOL, and notable diversity shifts in the gut microbiome, making it a valuable strategy in the evolving landscape of IBS care. [ABSTRACT FROM AUTHOR]

Objective: To compare the outcomes associated with the use of probiotics, prebiotics, and synbiotics for the treatment of chronic constipation in adults. Methods: We searched eight electronic databases from database inception to July 11, 2023, to identify randomized controlled trials (RCTs) that report efficacy and safety for the treatment of chronic constipation. The risk of bias in the included RCTs was evaluated according to the Cochrane tool, and the certainty of the evidence was assessed using the Confidence in Network Meta-Analysis framework. The analysis was conducted using R version 4.3.0. Results: Out of the 37 RCTs, a total of 21 different types of interventions were reported, involving 3,903 patients. This NMA demonstrated that both prebiotics and synbiotics resulted in an increase in frequency of stool movements per week. Compared to placebo, lactulose (Mean difference [MD] = 3.39, 95% Confdence interval [CI] [1.13, 5.65], moderate certainty), mix2 (consisting of Lactulose and Bacillus coagulans) (MD = 3.63, 95% CI [1.37, 5.89], moderate certainty), mix6 (consisting of Lactulose and Bifidobacterium coagulans) (MD = 4.30, 95% CI [1.04, 7.54], low certainty), and mix7 (consisting of Lactulose, Bifidobacterium subtilis, and Enterococcus faecium) (MD = 4.58, 95% CI [1.35, 7.78], moderate certainty) exhibited a significant effect. Notably, mix7 demonstrated the highest probability of being the most effective intervention (94.8%). Furthermore, when compared to L. plantarum, four probiotics and two synbiotics showed significant advantages in the Patient Assessment of Constipation Symptoms (PAC-SYM) score. L. reuteri (MD = -13.74, 95% CI [-22.20, -4.66], very low certainty) exhibited a significant effect in improving the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. In terms of safety, there were no statistically significant differences between the intervention and control groups in all adverse event analyses. Conclusions: Moderate to very low evidence supports the use of lactulose and synbiotics to increase the number of weekly stool movements in patients, particularly highlighting the significant impact of synbiotics in increasing the number of weekly stool movements in patients with constipation. The use of L. paracasei showed improvements in PAC-SYM scores, while L. reuteri demonstrated enhancements in PAC-QoL scores. [ABSTRACT FROM AUTHOR]

To mitigate the losses due to fall armyworm (FAW) infestation in maize, chemical pesticides had been the first choice and widely used as an emergency response. However, it comes with attendant health effect. This necessitates the development of plant based effective and safer pesticides. This research investigate response of fall armyworm larvae when they are exposed to crude and partially purified Tithonia diversifolia leaf extract. Chemical constituent of the extract was identified using NIST08.LIB library spectra provided by the software on a GC-MS system and FTIR analysis was done using KBr pellet technique with a resolution and scanning speed of 4 cm−1 and 2 mm/s. Dose dependent toxicity assay of T. diversifolia extracts on FAW at different growth stages under controlled environment in laboratory, followed by its effect under phytotron were examined against control and azadirachtin from neem. The GC-MS of the butanol eluent revealed 20 compounds out of which the major ones being beta-d-glucopyranoside, methyl (15.225 %) palmitic acid, TMS derivative (10.98 %) and hexadecanoic acid, 2-[(trimethylsily)oxy]-, methyl ester (8.75 %). The FT-IR spectroscopic analysis of the butanol eluent of T. diversifolia leaf extract revealed the presence of alcohols, phenols, aldehydes, ketones, alkanes and primary amines. The butanol eluent and crude extract caused 96 % mortality at neonate and first instar FAW larvae. The toxic and repellant effects revealed by diet bioassay and phytotron experiment respectively suggest that butanol eluent of T. diversifolia leaf extract could be a good and effective target for biopesticide production against FAW. [ABSTRACT FROM AUTHOR]

Glycoconjugate vaccines are based on chemical conjugation of pathogen‐associated carbohydrates with immunogenic carrier proteins and are considered a very cost‐effective way to prevent infections. Most of the licensed glycoconjugate vaccines are composed of saccharide antigens extracted from bacterial sources. However, synthetic oligosaccharide antigens have become a promising alternative to natural polysaccharides with the advantage of being well‐defined structures providing homogeneous conjugates. Haemophilus influenzae (Hi) is responsible for a number of severe diseases. In recent years, an increasing rate of invasive infections caused by Hi serotype a (Hia) raised some concern, because no vaccine targeting Hia is currently available. The capsular polysaccharide (CPS) of Hia is constituted by phosphodiester‐linked 4‐β‐d‐glucose‐(1→4)‐d‐ribitol‐5‐(PO4→) repeating units and is the antigen for protein‐conjugated polysaccharide vaccines. To investigate the antigenic potential of the CPS from Hia, we synthesized related saccharide fragments containing up to five repeating units. Following the synthetic optimization of the needed disaccharide building blocks, they were assembled using the phosphoramidite approach for the installation of the phosphodiester linkages. The resulting CPS‐based Hia oligomers were conjugated to CRM197 carrier protein and evaluated in vivo for their immunogenic potential, showing that all glycoconjugates were capable of raising antibodies recognizing Hia synthetic fragments. [ABSTRACT FROM AUTHOR]

The Gal(α1‐3)Gal is the terminal disaccharide unit of the α‐Gal epitope [Gal(α1‐3)Gal(β1‐4)GlcNAc], an exogenous antigenic determinant with several clinical implications, found in all non‐primate mammals and in several dangerous pathogens, including certain protozoa and mycobacteria. Its absence in humans makes the α‐Gal epitope an interesting target for several infectious diseases. Here we present the development of a macrocyclic tweezers‐shaped receptor, resulting from the combination of the structural features of two predecessors belonging to the family of diaminocarbazole receptors, which exhibits binding properties in the low millimolar range toward the Gal(α1‐3)Gal disaccharide of the α‐Gal antigen. [ABSTRACT FROM AUTHOR]

Background and objective: The disaccharide loading test is a method to assess gastric mucosal damage. Since Trelan-G75, which is used for the sugar tolerance test, contains disaccharide maltose, if maltose is detected at a high sensitivity in the sample blood used in the sugar tolerance test, screening for upper gastrointestinal mucosal damage can be made simultaneously with the sugar tolerance test for the diagnosis of diabetes. Methods: Glucose-6-phosphate is generated by treating maltose with maltose phosphorylase, β-phosphoglucomutase, and glucose-1,6-bisphosphate. Then, change in the absorbance at 405 nm is measured by the enzymatic cycling method using Thio-NADP, β-NADPH, and Glucose-6-phosphate dehydrogenase. After evaluating the optimal condition for this method, it is mounted on an automatic biochemical analyzer, and samples after the sugar tolerance test were assayed. Results: Regarding the performance of this method, the repeatability was 10–50 μmol/L with a CV of ≤1.1%. Concerning the assay range, a curve passing the origin with a range of linearity up to 120 μmol/L was obtained. No effect of dyes or sugars in the blood was noted. As a result of application to patients with gastric mucosal disorders (those who had a health checkup), significant differences were observed depending on the stage of atrophic gastritis. Discussion: This method has a high sensitivity and a high precision and can be used for high-speed analysis on an automatic analyzer. It has the potential to be used as a screening test for gastric mucosal damage. [ABSTRACT FROM AUTHOR]

Summary: We previously demonstrated that among various histological types of human testicular germinal cell tumors (GCTs), embryonal carcinoma (EC) preferentially expresses low-sulfated keratan sulfate (KS) consisting of repeating N -acetyllactosamine (LacNAc) disaccharide units composed of galactose and 6- O -sulfated N -acetylglucosamine (GlcNAc), which is recognized by the R-10G antibody. Recently, we generated another anti-low-sulfated KS monoclonal antibody, 294-1B1. Immunohistochemical analysis of testicular GCTs (n =83) revealed that the low-sulfated KS recognized by 294-1B1 is also preferentially expressed in EC but minimally in other GCT histological types. Moreover, immunolabeling with R-10G and 294-1B1 antibodies was resistant to peptide- N -glycosidase F digestion, and EC was not stained with the MECA-79 antibody, indicating that low-sulfated KS expressed in EC contains mucin-type core 2 O -glycans carrying GlcNAc-6- O -sulfated oligo-LacNAc. Double immunofluorescence staining showed that R-10G and 294-1B1 antibody signals colocalized with those for podocalyxin (PODXL). Furthermore, western blot analysis of recombinant human PODXL•IgG fusion proteins secreted from low-sulfated KS-expressing human embryonic kidney 293T cells revealed that PODXL functions as a core protein for low-sulfated KS. Taken together, these findings strongly suggest that the PODXL glycoform decorated with low-sulfated KS is preferentially expressed in human testicular EC and may therefore serve as a diagnostic marker for this malignancy [ABSTRACT FROM AUTHOR]

Tuberculosis remains a large global disease burden for which treatment regimens are protracted and monitoring of disease activity difficult. Existing detection methods rely almost exclusively on bacterial culture from sputum which limits sampling to organisms on the pulmonary surface. Advances in monitoring tuberculous lesions have utilized the common glucoside [18F]FDG, yet lack specificity to the causative pathogen Mycobacterium tuberculosis (Mtb) and so do not directly correlate with pathogen viability. Here we show that a close mimic that is also positron-emitting of the non-mammalian Mtb disaccharide trehalose – 2-[18F]fluoro-2-deoxytrehalose ([18F]FDT) – is a mechanism-based reporter of Mycobacteria-selective enzyme activity in vivo. Use of [18F]FDT in the imaging of Mtb in diverse models of disease, including non-human primates, successfully co-opts Mtb-mediated processing of trehalose to allow the specific imaging of TB-associated lesions and to monitor the effects of treatment. A pyrogen-free, direct enzyme-catalyzed process for its radiochemical synthesis allows the ready production of [18F]FDT from the most globally-abundant organic 18F-containing molecule, [18F]FDG. The full, pre-clinical validation of both production method and [18F]FDT now creates a new, bacterium-selective candidate for clinical evaluation. We anticipate that this distributable technology to generate clinical-grade [18F]FDT directly from the widely-available clinical reagent [18F]FDG, without need for either custom-made radioisotope generation or specialist chemical methods and/or facilities, could now usher in global, democratized access to a TB-specific PET tracer. Current methods for detection of tuberculosis rely mostly on bacterial culture from sputum. Here, the authors provide preclinical evidence that a positron-emitting mimic of the disaccharide trehalose ([18F]FDT) can be used as a radiotracer for the imaging of tuberculosis-associated lesions and monitoring the effects of treatment. [ABSTRACT FROM AUTHOR]

Glycosaminoglycans (GAGs) are linear and acidic polysaccharides. They are ubiquitous molecules, which are involved in a wide range of biological processes. Despite being structurally simple at first glance, with a repeating backbone of alternating hexuronic acid and hexosamine dimers, GAGs display a highly complex structure, which predominantly results from their heterogeneous sulfation patterns. The commonly applied method for compositional analysis of all GAGs is "disaccharide analysis." In this process, GAGs are enzymatically depolymerized into disaccharides, derivatized with a fluorescent label, and then analysed through liquid chromatography. The limiting factor in the high throughput analysis of GAG disaccharides is the time‐consuming liquid chromatography. To address this limitation, we here utilized trapped ion mobility‐mass spectrometry (TIM‐MS) for the separation of isomeric GAG disaccharides, which reduces the measurement time from hours to a few minutes. A full set of disaccharides comprises twelve structures, with eight possessing isomers. Most disaccharides cannot be differentiated by TIM‐MS in underivatized form. Therefore, we developed chemical modifications to reduce sample complexity and enhance differentiability. Quantification is performed using stable isotope labelled standards, which are easily available due to the nature of the performed modifications. [ABSTRACT FROM AUTHOR]

This article delves into the synthesis and biological evaluation of sulfated and sulfonated disaccharide analogs, exploring their interactions with toll-like receptor 4 (TLR4) and their potential as drug candidates for inflammatory diseases. A significant aspect of the study is the examination of these analogs as inhibitors of heparanase, an enzyme that cleaves glycosidic linkages in heparan sulfate, producing proinflammatory fragments that activate TLR4. The research presents a comparative analysis of sulfate and sulfonate groups in these compounds, evaluating their synthesis, biological activity, and specific roles in TLR4-mediated immune responses, with a particular focus on their ability to modulate heparanase activity. Compound 9 (6,60-disulfonated disaccharide from methyl cellobioside) emerged as a potent TLR4 activator and a promising candidate for inflammatory drug development, exhibiting notable specificity and efficacy. The IC50 values for heparanase inhibition varied, highlighting distinct efficacy profiles for sulfonated and sulfated analogs, with cellobiose derivatives showing notable differences in inhibition capabilities. [ABSTRACT FROM AUTHOR]

The disaccharide (β-D-glucopyranosyluronic acid)-(1→4)-β-D-glucopyranoside represents a repeating unit of the capsular polysaccharide of Streptococcus pneumoniae serotype 3. A conjugate of the disaccharide with BSA (di-BSA conjugate) adjuvanted with aluminum hydroxide induced -- in contrast to the non-adjuvanted conjugate -- IgG1 antibody production and protected mice against S. pneumoniae serotype 3 infection after intraperitoneal prime-boost immunization. Adjuvanted and non-adjuvanted conjugates induced production of Th1 (IFNγ, TNFα); Th2 (IL-5, IL-13); Th17 (IL-17A), Th1/Th17 (IL-22), and Th2/Th17 cytokines (IL-21) after immunization. The concentration of cytokines in mice sera was higher in response to the adjuvanted conjugate, with the highest level of IL-17A production after the prime and boost immunizations. In contrast, the non-adjuvanted conjugate elicited only weak production of IL-17A, which gradually decreased after the second immunization. After boost immunization of mice with the adjuvanted di-BSA conjugate, there was a significant increase in the number of CD45+/CD19+ B cells, TCR+ γδ T cell, CD5+ В1 cells, and activated cells with MHC II+ expression in the spleens of the mice. IL-17A, TCR+ γδ T cells, and CD5+ В1 cells play a crucial role in preventing pneumococcal infection, but can also contribute to autoimmune diseases. Immunization with the adjuvanted and non-adjuvanted di-BSA conjugate did not elicit autoantibodies against double-stranded DNA targeting cell nuclei in mice. Thus, the molecular and cellular markers associated with antibody production and protective activity in response to immunization with the di-BSA conjugate adjuvanted with aluminum hydroxide are IL-17A, TCR+ γδ T cells, and CD5+ В1 cells against the background of increasing MHC II+ expression. [ABSTRACT FROM AUTHOR]

Solution nuclear magnetic resonance (NMR) analysis of polysaccharides can provide valuable information not only on their primary structures but also on their conformation, dynamics, and interactions under physiological conditions. One of the main problems is that non‐anomeric 1H signals typically overlap, and this often hinders detailed NMR analysis. Isotope enrichment, such as with 13C and 15N, will add a new dimension to the NMR spectra of polysaccharides, and spectral analysis can be performed with enhanced sensitivity using isolated peaks. For this purpose, here we have prepared uniformly 13C‐ and/or 15N‐labeled chondroitin polysaccharides –4)‐β‐D‐glucuronopyranosyl‐(1–3)‐2‐acetamido‐2‐deoxy‐β‐D‐galactopyranosyl‐(1– with molecular weights in the range from 310 to 460 k by bacterial fermentation. The enrichment ratios for 13C and 15N were 98.9 and 99.8%, respectively, based on the mass spectrometric analysis of the constituent chondroitin disaccharides. 1H and 13C NMR signals were assigned mainly based on HSQC and 13C‐detection experiments including INADEQUATE, HETCOR, and HETCOR‐TOCSY. The carbonyl carbon signal of the N‐acetyl‐β‐D‐galactosamine residue was unambiguously distinguished from the C6 carbon of the β‐D‐glucuronic acid residue by the observation of 13C peak splitting due to 1JCN coupling in 13C‐ and 15N‐labeled chondroitin. The T2* and T1 were measured and indicate that both rigid and mobile sites are present in the long sequence of chondroitin. The conformation, dynamics, and interactions of chondroitin and its derivatives will be further analyzed based on the results obtained in this study. [ABSTRACT FROM AUTHOR]

In the treatment of experimental neurodegeneration with disaccharide trehalose, various regimens are used, predominantly a 2% solution, drunk for several weeks. We studied the effects of different regimens of dietary trehalose treatment in an amyloid-β (Aβ) 25–35-induced murine model of Alzheimer's disease (AD). Aβ-treated mice received 2% trehalose solution daily, 4% trehalose solution daily (continuous mode) or every other day (intermittent mode), to drink for two weeks. We revealed the dose-dependent effects on autophagy activation in the frontal cortex and hippocampus, and the restoration of behavioral disturbances. A continuous intake of 4% trehalose solution caused the greatest activation of autophagy and the complete recovery of step-through latency in the passive avoidance test that corresponds to associative long-term memory and learning. This regimen also produced an anxiolytic effect in the open field. The effects of all the regimens studied were similar in Aβ load, neuroinflammatory response, and neuronal density in the frontal cortex and hippocampus. Trehalose successfully restored these parameters to the levels of the control group. Thus, high doses of trehalose had increased efficacy towards cognitive impairment in a model of early AD-like pathology. These findings could be taken into account for translational studies and the development of clinical approaches for AD therapy using trehalose. [ABSTRACT FROM AUTHOR]

In an experimental model of Alzheimer's disease in mice, oral administration of trehalose disaccharide reduces neuroinflammation assessed by the expression level of microglia activation marker Iba1 and affects the neutrophil degranulation activity. A potential anti-inflammatory effect of 4% trehalose solution associated with a decrease in the activity of leukocyte elastase in plasma was revealed. [ABSTRACT FROM AUTHOR]

Bothersome gastrointestinal (GI) signs/symptoms, including abdominal pain, distension, nausea, and flatulence, are common in children. A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is frequently recommended for children with GI symptoms. Currently, there are no studies on the effect of FODMAPs in healthy schoolchildren. In this cross-sectional study, schoolchildren reported an association between FODMAPs and GI symptoms through a standardized questionnaire and images of 20 common staples known to be rich in FODMAPs. A total of 208 schoolchildren aged 8–18 years old participated. A proportion of 38.0% of children reported GI symptoms, with abdominal pain (33%) being the most common complaint followed by abdominal distension (24%) and nausea (23%). The majority of children who reported intolerances to FODMAP-containing foods were intolerant to less than two food groups (76%). While vegetables and legumes (26%), particularly black beans (11%) and onions (7%), emerged as the most common group of triggers, milk (12%) stood out as the single food most frequently associated with GI symptoms. In conclusion, there was a high prevalence of FODMAPs intolerance among schoolchildren. Larger studies are recommended to confirm these findings and to inform possible dietary interventions to reduce the effect of FODMAPs on schoolchildren. [ABSTRACT FROM AUTHOR]

Gluten-free foods (GF) availability on supermarket shelves is growing and it is expected to continue expanding in the years ahead. These foods have been linked to a lower content of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), molecules that trigger gastrointestinal symptoms in sensitive persons. In this study, the FODMAP content of 25 cereal-based GF foods in Spain (breakfast cereals, pasta, bread, biscuits, bakery products, and dough and puff pastry) and 25 gluten-containing equivalents (GC) available in the same supermarket were analysed and compared. Lactose, fructose, glucose, sorbitol, mannitol, raffinose, stachyose and fructans were quantified. In a like-by-like analysis, GF foods were found to generally contain fewer FODMAPs than their GC counterparts. The ingredients used in the manufacture of GF cereal-based foods may contribute to this fact. When the individually wrapped size was considered, the proportion of samples classified as high-FODMAPs in GC and GF foods showed a trend towards fewer samples in the GF. However, not all the GF samples were low-FODMAP. Altogether, our findings provide essential information for FODMAP content databases of GF products in Spain. [ABSTRACT FROM AUTHOR]

BackgroundAlterations in gastrointestinal (GI) microbial composition have been reported in patients with systemic sclerosis (SSc). However, it is unclear to what degree these alterations and/or dietary changes contribute to the SSc-GI phenotype.ObjectivesOur study aimed to 1) evaluate the relationship between GI microbial composition and SSc-GI symptoms, and 2) compare GI symptoms and GI microbial composition between SSc patients adhering to a low versus non-low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet.MethodsAdult SSc patients were consecutively recruited to provide stool specimens for bacterial 16S rRNA gene sequencing. Patients completed the UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument (GIT 2.0) and the Diet History Questionnaire (DHQ) II and were classified as adhering to a low or non-low FODMAP diet. GI microbial differences were assessed using three metrics of alpha diversity (species richness, evenness, and phylogenetic diversity), as well as beta diversity (overall microbial composition). Differential abundance analysis was performed to identify specific genera associated with SSc-GI phenotype and low versus non-low FODMAP diet.ResultsOf the 66 total SSc patients included, the majority were women (n = 56) with a mean disease duration of 9.6 years. Thirty-five participants completed the DHQ II. Increased severity of GI symptoms (total GIT 2.0 score) was associated with decreased species diversity and differences in GI microbial composition. Specifically, pathobiont genera (e.g., Klebsiella and Enterococcus) were significantly more abundant in patients with increased GI symptom severity. When comparing low (N = 19) versus non-low (N = 16) FODMAP groups, there were no significant differences in GI symptom severity or in alpha and beta diversity. Compared with the low FODMAP group, the non-low FODMAP group had greater abundance of the pathobiont Enterococcus.ConclusionSSc patients reporting more severe GI symptoms exhibited GI microbial dysbiosis characterized by less species diversity and alterations in microbial composition. A low FODMAP diet was not associated with significant alterations in GI microbial composition or reduced SSc-GI symptoms; however, randomized controlled trials are needed to evaluate the impact of specific diets on GI symptoms in SSc.

Starfish provide important saponins with diverse bioactivities as the secondary metabolites, among which 2‐O‐glycosylated glycosides are commonly found. Preparation of those 1,2‐trans 2‐O‐glycosylated glycosides usually relies on 2‐O‐acyl participation requiring the selective installation and cleavage of 2‐O‐acyl groups. A convergent synthesis using 2‐O‐glycosylated oligosaccharide donors would be more straightforward but also pose greater challenges. Herein, we report a convergent synthesis of a distinctive tetrasaccharide isolated from starfish Asterias rollestoni Bell. Dual 2‐(diphenylphosphinoyl)acetyl (DPPA) groups at O3 and O4 on galactose moiety led to high β‐selectivities (β/α=12/1 or β only) in the challenging [2+2] glycosylation, giving the desired tetrasaccharides in >90 % yields from the 2‐O‐glycosylated disaccharide donors. These synthetic studies have also unambiguously revised the structure of these natural tetrasaccharides. This work would facilitate further studies on new inhibitors of α‐glucosidase as hypoglycemic drugs. [ABSTRACT FROM AUTHOR]

The intestinal anaerobic bacterium Akkermansia muciniphila is specialized in the degradation of mucins, which are heavily O-glycosylated proteins that constitute the major components of the mucus lining the intestine. Despite that adhesion to mucins is considered critical for the persistence of A. muciniphila in the human intestinal tract, our knowledge of how this intestinal symbiont recognizes and binds to mucins is still limited. Here, we first show that the mucin-binding properties of A. muciniphila are independent of environmental oxygen concentrations and not abolished by pasteurization. We then dissected the mucin-binding properties of pasteurized A. muciniphila by use of a recently developed cell-based mucin array that enables display of the tandem repeats of human mucins with distinct O-glycan patterns and structures. We found that A. muciniphila recognizes the unsialylated LacNAc (Galβ1-4GlcNAcβ1-R) disaccharide selectively on core2 and core3 O-glycans. This disaccharide epitope is abundantly found on human colonic mucins capped by sialic acids, and we demonstrated that endogenous A. muciniphila neuraminidase activity can uncover the epitope and promote binding. In summary, our study provides insights into the mucin-binding properties important for colonization of a key mucin-foraging bacterium. Intestinal mucus consists of densely O-glycosylated mucins, serving as a nutrient source for bacteria. Elzinga et al. show that mucin-degrading Akkermansia muciniphila selectively binds to O-glycan structures found on human colonic mucins. [ABSTRACT FROM AUTHOR]

We evaluated changes in hyperhydration and beverage hydration index (BHI, a composite measure of fluid balance after consuming a test beverage relative to water) during resting, induced by the consumption of beverages containing glycerol and sodium supplemented with fast-absorbing sucrose or slow-absorbing isomaltulose. In a randomized crossover, single-blinded protocol (clinical trials registry: UMIN000042644), 14 young physically active adults (three women) consumed 1 L of beverage containing either 7% glycerol + 0.5% sodium (Gly + Na), Gly + Na plus 7% sucrose (Gly + Na + Suc), Gly + Na plus 7% isomaltulose (Gly + Na + Iso), or water (CON) over a 40 min period. We assessed the change in plasma volume (ΔPV), BHI (calculated from cumulative urine output following consumption of water relative to that of the beverage), and blood glucose and sodium for 180 min after initiating ingestion. Total urine volume was reduced in all beverages containing glycerol and sodium compared to CON (all P ≤ 0.002). The addition of isomaltulose increased BHI by ∼45% (3.43 ± 1.0 vs. 2.50 ± 0.7 for Gly + Na, P = 0.011) whereas sucrose did not (2.6 ± 0.6, P = 0.826). The PV expansion was earliest for Gly + Na (30 min), slower for Gly + Na + Suc (90 min), and slowest for Gly + Na + Iso (120 min) with a concomitant lag in the increase of blood glucose and sodium concentrations. Supplementation of beverages containing glycerol and sodium with isomaltulose but not sucrose enhances BHI from those of glycerol and sodium only under a resting state, likely due to the slow absorption of isomaltulose-derived monosaccharides (i.e., glucose and fructose). [ABSTRACT FROM AUTHOR]

Intelectins belong to a family of lectins with specific and transitory carbohydrate interaction capabilities. These interactions are related to the activity of agglutinating pathogens, as intelectins play a significant role in immunity. Despite the prominent immune defense function of intelectins, limited information about its structural characteristics and carbohydrate interaction properties is available. This study investigated an intelectin transcript identified in RNA-seq data obtained from the South American lungfish (Lepidosiren paradoxa), namely LpITLN2-B. The structural analyses predicted LpITLN2-B to be a homo-trimeric globular protein with the fibrinogen-like functional domain (FReD), exhibiting a molecular mass of 57 kDa. The quaternary structure is subdivided into three monomers, A, B, and C, and each domain comprises 11 β-sheets: an anti-parallel β-sheet, a β-hairpin, and a disordered β-sheet structure. Molecular docking demonstrates a significant interaction with disaccharides rather than monosaccharides. The preferential interaction with disaccharides highlights the potential interaction with pathogen molecules, such as LPS and Poly(I:C). The hemagglutination assay inhibited lectins activity, especially maltose and sucrose, highlighting lectin activity in L. paradoxa samples. Overall, our results show the potential relevance of LpITLN2-B in L. paradoxa immune defense against pathogens. [ABSTRACT FROM AUTHOR]

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The burgeoning issue of landfill leachate, exacerbated by urbanization, necessitates evaluating its biological impact, traditionally overshadowed by physical and chemical assessments. This study harnesses Caenorhabditis elegans, a model organism, to elucidate the physiological toxicity of landfill leachate subjected to different treatment processes: nanofiltration reverse osmosis tail water (NFRO), membrane bioreactor (MBR), and raw leachate (RAW). Our investigation focuses on the modulation of sugar metabolism, particularly trehalose—a disaccharide serving dual functions as an energy source and an anti-adversity molecule in invertebrates. Upon exposure, C. elegans showcased a 60–70% reduction in glucose and glycogen levels alongside a significant trehalose increase, highlighting an adaptive response to environmental stress by augmenting trehalose synthesis. Notably, trehalose-related genes in the NFRO group were up-regulated, contrasting with the MBR and RAW groups, where trehalose synthesis genes outpaced decomposition genes by 20–30 times. These findings suggest that C. elegans predominantly counters landfill leachate-induced stress through trehalose accumulation. This research not only provides insights into the differential impact of leachate treatment methods on C. elegans but also proposes a molecular framework for assessing the environmental repercussions of landfill leachate, contributing to the development of novel strategies for pollution mitigation and environmental preservation. [ABSTRACT FROM AUTHOR]

Rare sugars are known for their ability to suppress postprandial blood glucose levels. Therefore, oligosaccharides and disaccharides derived from rare sugars could potentially serve as functional sweeteners. A disaccharide [α-d-allopyranosyl-(1→2)-β-d-psicofuranoside] mimicking sucrose was synthesized from rare monosaccharides D-allose and D-psicose. Glycosylation using the intermolecular aglycon delivery (IAD) method was employed to selectively form 1,2-cis α-glycosidic linkages of the allopyranose residues. Moreover, β-selective psicofuranosylation was performed using a psicofuranosyl acceptor with 1,3,4,6-tetra-O-benzoyl groups. This is the first report on the synthesis of non-reducing disaccharides comprising only rare d-sugars by IAD using protected ketose as a unique acceptor; additionally, this approach is expected to be applicable to the synthesis of functional sweeteners. [ABSTRACT FROM AUTHOR]

Sugar transport proteins (STPs) are high‐affinity H+‐coupled hexose symporters. Recently, the contribution of STP13 to bacterial and fungal pathogen resistance across multiple plant species has garnered significant interest. Quantitative PCR analysis of source leaves, developing embryos, and seed coats of Phaseolus vulgarisL. (common bean) revealed that PvSTP13.1 was expressed in source leaves and seed coats throughout seed development. In contrast, PvSTP13.1 transcripts were detected at exceedingly low levels in developing embryos. To characterize the transport mechanism, PvSTP13.1 was expressed in Xenopus laevis oocytes, and inward‐directed currents were analyzed using two‐electrode voltage clamping. PvSTP13.1 was shown to function as an H+‐coupled monosaccharide symporter exhibiting a unique high affinity for hexoses and aldopentoses at depolarized membrane potentials. Specifically, of the 31 assessed substrates, which included aldohexoses, deoxyhexoses, fructose, 3‐O‐methyl‐D‐glucose, aldopentoses, polyols, glycosides, disaccharides, trisaccharides, and glucuronic acid, PvSTP13.1 displayed the highest affinity (K0.5) for glucose (43 μM), mannose (92 μM), galactose (145 μM), fructose (224 μM), xylose (1.0 mM), and fucose (3.7 mM) at pH 5.6 at a depolarized membrane potential of −40 mV. The results presented here suggest PvSTP13.1 contributes to retrieval of hexoses from the apoplasmic space in source leaves and coats of developing seeds. [ABSTRACT FROM AUTHOR]

Glycans are central to information content and regulation in biological systems. These carbohydrate molecules are active either as oligo‐ or polysaccharides, often in the form of glycoconjugates. The monosaccharide entities are joined by glycosidic linkages and stereochemical arrangements are of utmost importance in determining conformation and flexibility of saccharides. The conformational preferences and population distributions at the glycosidic torsion angles φ and ψ have been investigated for O‐methyl glycosides of three disaccharides where the substitution takes place at a secondary alcohol, viz., in α‐l‐Fucp‐(1→3)‐β‐d‐Glcp‐OMe, α‐l‐Fucp‐(1→3)‐α‐d‐Galp‐OMe and α‐d‐Glcp‐(1→4)‐α‐d‐Galp‐OMe, corresponding to disaccharide structural elements present in bacterial polysaccharides. Stereochemical differences at or adjacent to the glycosidic linkage were explored by solution state NMR spectroscopy using one‐dimensional 1H,1H‐NOESY NMR experiments to obtain transglycosidic proton‐proton distances and one‐ and two‐dimensional heteronuclear NMR experiments to obtain 3JCH transglycosidic coupling constants related to torsion angles φ and ψ. Computed effective proton‐proton distances from molecular dynamics (MD) simulations showed excellent agreement to experimentally derived distances for the α‐(1→3)‐linked disaccharides and revealed that for the bimodal distribution at the ψ torsion angle for the α‐(1→4)‐linked disaccharide experiment and simulation were at variance with each other, calling for further force field developments. The MD simulations disclosed a highly intricate inter‐residue hydrogen bonding pattern for the α‐(1→4)‐linked disaccharide, including a nonconventional hydrogen bond between H5′ in the glucosyl residue and O3 in the galactosyl residue, supported by a large downfield 1H NMR chemical shift displacement compared to α‐d‐Glcp‐OMe. Comparison of population distributions of the glycosidic torsion angles φ and ψ in the disaccharide entities to those of corresponding crystal structures highlighted the potential importance of solvation on the preferred conformation. [ABSTRACT FROM AUTHOR]

Phospholipids, PLs, are interesting and highly abundant amphiphilic molecules, which self‐assemble into 3D nanostructures that have big interest as formulation excipients in, for example, pharma industry. However, the structures that are formed by naturally occurring PLs usually suffer from rigidity problems, and the nanostructures have to be modified in various ways for improved stability. One such approach is by the conjugation of saccharides to the PL head group. In this study, we investigate reaction conditions for the scalable phospholipase D–catalyzed transphosphatidylation reaction for the synthesis of glycophospholipids. Biphasic reaction systems with different solvents are compared with a purely aqueous system with PLs dispersed as vesicles. The investigations showed that use of the biphasic system containing chloroform and a glucose/phosphatidylcholine ratio of 50, in combination with carefully selected enzyme concentration and reaction time, led to an optimized process without any hydrolytic side reaction for the synthesis of phosphatidyl glucose. The reaction system was then applied to a variety of different mono‐ and disaccharides for the synthesis of a range of different glycophospholipids, resulting in yields up to 85% of phosphatidyl monosaccharides and 35% of disaccharides. Practical Application: Phospholipids and other polar lipids are of great scientific interest as formulation excipients. The chemical structures of lipids used for such applications have major impact on the properties of the self‐aggregated systems. Synthesis of new phospholipids with modified head groups can tremendously widen the portfolio of available choices of formulation excipients and make it possible to make customized formulations with the desired properties. The introduction of saccharides in the hydrophilic part of the phospholipid alters the chemistry of head group and its interaction with surrounding water in vesicle systems and should therefore have a significant effect on its formulating properties compared to natural phospholipids. [ABSTRACT FROM AUTHOR]

Reducing sugars can spontaneously react with free amines in protein side chains leading to posttranslational modifications (PTMs) called glycation. In contrast to glycosylation, glycation is a non-enzymatic modification with consequences on the overall charge, solubility, aggregation susceptibility and functionality of a protein. Glycation is a critical quality attribute of therapeutic monoclonal antibodies. In addition to glucose, also disaccharides like maltose can form glycation products. We present here a detailed NMR analysis of the Amadori product formed between proteins and maltose. For better comparison, data collection was done under denaturing conditions using 7 M urea-d4 in D2O. The here presented correlation patterns serve as a signature and can be used to identify maltose-based glycation in any protein that can be denatured. In addition to the model protein BSA, which can be readily glycated, we present data of the biotherapeutic abatacept containing maltose in its formulation buffer. With this contribution, we demonstrate that NMR spectroscopy is an independent method for detecting maltose-based glycation, that is suited for cross-validation with other methods. [ABSTRACT FROM AUTHOR]

This study investigated the effects of 7 days of 600 mg/day anthocyanin-rich blackcurrant extract intake on small intestinal permeability, enterocyte damage, microbial translocation, and inflammation following exertional heat stress. Twelve recreationally active men (maximal aerobic capacity = 55.6 ± 6.0 ml·kg−1·min−1) ran (70% VO2max) for 60 min in an environmental chamber (34 °C, 40% relative humidity) on two occasions (placebo/blackcurrant, randomized double-blind crossover). Permeability was assessed from a 4-hr urinary excretion of lactulose and rhamnose and expressed as a ratio of lactulose/rhamnose. Venous blood samples were taken at rest and 20, 60, and 240 min after exercise to measure enterocyte damage (intestinal fatty acid-binding protein); microbial translocation (soluble CD14, lipopolysaccharide-binding protein); and interleukins 6, interleukins 10, and interleukins 1 receptor antagonist. Exercise increased rectal temperature (by ∼2.8 °C) and heart rate (by ∼123 beats/min) in each condition. Blackcurrant supplementation led to a ∼12% reduction in lactulose/rhamnose ratio (p <.0034) and enterocyte damage (∼40% reduction in intestinal fatty acid-binding protein area under the curve; p <.0001) relative to placebo. No between-condition differences were observed immediately after exercise for lipopolysaccharide-binding protein (mean, 95% confidence interval [CI]; +80%, 95% CI [+61%, +99%]); soluble CD14 (+37%, 95% CI [+22%, +51%]); interleukins 6 (+494%, 95% CI [+394%, +690%]); interleukins 10 (+288%, 95% CI [+105%, +470%]); or interleukins 1 receptor antagonist (+47%, 95% CI [+13%, +80%]; all time main effects). No between-condition differences for these markers were observed after 60 or 240 min of recovery. Blackcurrant extract preserves the GI barrier; however, at subclinical levels, this had no effect on microbial translocation and downstream inflammatory processes. [ABSTRACT FROM AUTHOR]

The enzyme‐resistant thioglycosides are highly valuable immunogens because of their enhanced metabolic stability. We report the first synthesis of a family of thiooligosaccharides related to the capsular polysaccharides (CPS) of Campylobacter jejuni HS:4 for potential use in conjugate vaccines. The native CPS structures of the pathogen consist of a challenging repeating disaccharide formed with β(1→4)‐linked 6‐deoxy‐β‐D‐ido‐heptopyranoside and N‐acetyl‐D‐glucosamine; the rare 6‐deoxy‐ido‐heptopyranosyl backbone and β‐anomeric configuration of the former monosaccharide makes the synthesis of this family of antigens very challenging. So far, no synthesis of the thioanalogs of the CPS antigens have been reported. The unprecedented synthesis presented in this work is built on an elegant approach by using β‐glycosylthiolate as a glycosyl donor to open the 2,3‐epoxide functionality of pre‐designed 6‐deoxy‐β‐D‐talo‐heptopyranosides. Our results illustrated that this key trans‐thioglycosylation can be designed in a modular and regio and stereo‐selective manner. Built on the success of this novel approach, we succeeded the synthesis of a family of thiooligosaccharides including a thiohexasaccharide which is considered to be the desired antigen length and complexity for immunizations. We also report the first direct conversion of base‐stable but acid‐labile 2‐trimethylsilylethyl glycosides to glycosyl‐1‐thioacetates in a one‐pot manner. [ABSTRACT FROM AUTHOR]

To further understand the specificity of muramyl dipeptide (MDP) sensing by NOD2, we evaluated the compatibility of synthetic MDP analogues for cellular uptake and NAGK phosphorylation, the pre-requisite steps of intracellular NOD2 activation. Our results revealed that these two prior steps do not confer ligand stereoselectivity; yet NAGK strictly discriminates against the disaccharide NOD2 agonists for phosphorylation in vitro, despite it being indispensable for the cellular NOD2-stimulating effects of these analogues, implying potential glycosidase cleavage as a novel intermediate step for cellular activation of NOD2. [ABSTRACT FROM AUTHOR]

Disaccharides are composed of two monosaccharide subunits joined by a glycosidic linkage in an α or β configuration. Different combinations of isomeric monosaccharide subunits and different glycosidic linkages result in different isomeric disaccharide products. Thus, direct discrimination of these disaccharide isomers from a mixture is extremely difficult. In this paper, a hetero‐octameric Mycobacterium smegmatis porin A (MspA) nanopore conjugated with a phenylboronic acid (PBA) adapter was applied for disaccharide sensing, with which three most widely known disaccharides in nature, including sucrose, lactose and maltose, were clearly discriminated. Besides, all six isomeric α‐D‐glucopyranosyl‐D‐fructoses, differing only in their glycosidic linkages, were also well resolved. Assisted by a custom machine learning algorithm, a 0.99 discrimination accuracy is achieved. Nanopore discrimination of disaccharide isomers with different glycosidic linkages, which has never been previously demonstrated, is inspiring for nanopore saccharide sequencing. This sensing capacity was also applied in direct identification of isomaltulose additives in a commercial sucrose‐free yogurt, from which isomaltulose, lactose and L‐lactic acid were simultaneously detected. [ABSTRACT FROM AUTHOR]

Water is essential for all active life processes. Despite this, there are a number of organisms that can survive prolonged desiccation. The vitrification hypothesis posits that such organisms survive desiccation by forming non-crystalline amorphous (vitrified) solids, often through the accumulation of protective disaccharides. In line with this theory, vitrification has been shown to be essential for desiccation tolerance in many organisms that survive extreme drying. However, it is known that not all vitrified materials are protective and that certain physio-chemical properties correlate with the protection in the glassy state. Furthermore, recent evidence suggests that the physio-chemical properties that correlate with protection can vary depending on the chemical nature of similarly sized protectants. While the chemistry of protectants has been probed in relation to the protective properties they induce when vitrified, the effect of protectant size on glassy properties and protection during drying has not been investigated. Here, we study the effect of the polymer size of sucrose on glassy properties associated with protection in the vitrified state. The monomer sucrose, and the polymers polysucrose 70 and polysucrose 400 (70 and 400 refer to the molecular weight of the polymers in kDa). Using these three different-sized sucrose polymers, we find that each of the glassy properties we investigated including; enzyme protection, water content, glass transition temperature, and glass former fragility, were affected by polymer size. However, only one vitrified property, glass transition temperature, correlated with protection during drying. This correlation is heavily dependent on sucrose polymer size. Increased glass transition midpoint temperature correlated positively with protection conferred by monomeric sucrose (p-value = 0.009, R2 = 0.840), whereas this correlation was bi-phasic for polysucrose 70, and had an inverse relationship for polysucrose 400 (p-value = 0.120, R2 = 0.490). Our results indicate that the size of vitrifying protectants can have a profound effect on glassy properties as well as on how these properties correlate with protection in the dry state. Beyond desiccation tolerance, these findings provide insights for the development of new technologies for the stabilization of biological material in the dry state. [ABSTRACT FROM AUTHOR]