Search Results (9,170)

This study evaluated the performance of Fourier-transform infrared (FTIR) spectroscopy for identifying spectral signatures associated with two key traits of Listeria monocytogenes: serogroup classification and biofilm-forming capacity. A total of 100 strains, previously serogrouped by PCR and categorized as high, intermediate, or low biofilm producers, were analyzed. Whole-genome sequencing was performed, and comparative genomics was conducted at core-genome, pangenome, and whole-genome (k-mer) levels to determine which genomic representation best reflected the phenotypes. Strains were typed using Fourier-Transform Infrared (FTIR Biotyper^® system from Bruker Daltonics GmbH and Co., Bremen, Germany) with five technical replicates. Spectral data from the polysaccharide region (1300–800 cm⁻¹) were extracted and used to train twelve statistical models within a machine learning pipeline combined with cross-validation to predict four serogroups and three biofilm clusters from 501 spectral variables. Genomic analyses showed strong concordance between population structure and serogroup, whereas biofilm formation displayed only weak genomic association, explaining less than 0.1% of genomic variance (PERMANOVA R² ≤ 0.001). Penalized discriminant analysis achieved the highest performance for serogroup prediction (overall accuracy 97.2%), while the k-nearest neighbor model performed best for biofilm prediction (74.8%). Two dedicated R Shiny applications were developed to facilitate model use. Overall, FTIR spectroscopy coupled with machine learning can provide a rapid and cost-effective alternative to PCR, genomic analyses, and in vitro assays for phenotypic trait prediction. Full article

The high prevalence of biofilm-associated multidrug-resistant (MDR) Escherichia coli infections in older adults calls for novel control strategies. This study compared fecal E. coli carriage, antimicrobial resistance, and biofilm formation among community-dwelling older adults with different self-reported immune statuses (lower vs. normal), and evaluated the antibiofilm activity of five Lactobacillus cell-free supernatants (CFSs). Fecal samples from 20 older adults were analyzed. E. coli was enumerated, and isolates were characterized for antimicrobial susceptibility and biofilm formation. Five Lactobacillus strains were screened for antibiofilm activity using crystal violet assay, with further evaluation of extracellular polymeric substance (EPS) production and biofilm morphology. After removing the redundant isolates, 70 isolates were reported, with significantly higher counts in the lower-immunity group (7.89 vs. 6.04 log MPN/g). The lower-immunity group had significantly higher antimicrobial resistance (97.3% vs. 60.6%), and higher MDR prevalence (91.7% vs. 24.2%). Biofilm formation was observed in 62.9% of isolates, with significantly higher prevalence among MDR isolates and in the lower-immunity group. L. paracasei L475 CFS showed the strongest antibiofilm activity against a representative MDR isolate (L5-1), with inhibition and eradication rates of 82.9% and 75.0%, respectively. Mechanistically, L475 CFS reduced extracellular polymeric substance components, with a 92.3% reduction in proteins and 41.3% in polysaccharides. Microscopy confirmed disrupted biofilm architecture, membrane damage, and cell lysis. In conclusion, these preliminary findings indicate a potential association between self-reported immune function and E. coli resistance/biofilm formation in older adults. L. paracasei L475 CFS demonstrates promising in vitro antibiofilm activity against an MDR E. coli isolate from this population, supporting its potential as a postbiotic candidate. Full article

Heat-induced softening of apple fruit varies markedly among cultivars; however, the biochemical factors underlying these differences remain incompletely understood. This study investigated the relationship between cell wall modifications and thermal flesh breakdown in three apple cultivars (‘Bramley’s Seedling’, ‘Fuji’, and ‘Toki’). Fruit flesh samples were heated under controlled conditions and analyzed for changes in texture properties, cell structure, cell wall composition, and molar mass distribution. Heating increased water-soluble pectin in all cultivars, with a markedly greater increase in ‘Bramley’s Seedling’, indicating pronounced pectin solubilization during thermal treatment. A pronounced shift from high- to low-molar-weight polymers in the Na₂CO₃-soluble fraction was also observed only in ‘Bramley’s Seedling’, suggesting extensive depolymerization of the Na₂CO₃-soluble pectic polymers. A decrease in hemicellulose and cellulose content following heating was observed exclusively in ‘Bramley’s Seedling’. Consistently, this cultivar exhibited significantly lower gumminess and chewiness compared with the other cultivars. Beyond compositional changes, ‘Bramley’s Seedling’ exhibited severe tissue disintegration and distinctive rheological behavior indicative of extensive cell rupture. In contrast, ‘Fuji’ and ‘Toki’ retained relatively stable cell wall structures and maintained tissue integrity after heating. These findings suggest that cultivar-dependent disassembly of cell wall polysaccharides, particularly pectin depolymerization and solubilization, is strongly associated with heat-induced tissue breakdown. Full article

In this study, a hydrogel was developed based on a chondroitin sulfate–iron complex (CSFe) incorporated into a sodium alginate matrix. The CSFe complex was first prepared through the interaction of chondroitin sulfate (CS) with Fe³⁺ ions, achieving an iron content of 2.06%. Structural characterization confirmed that Fe³⁺ coordinated with the carboxyl, sulfate, and N-acetyl groups of CS, resulting in increased molecular weight and altered physicochemical properties. The CSFe complex exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus (S. aureus), and was further incorporated into a sodium alginate matrix to form an injectable hydrogel with favorable physicochemical properties such as spreadability, shear-thinning behavior, and a compact porous microstructure. In a mouse model of S. aureus-infected wounds, the CSFe hydrogel significantly accelerated wound closure, reduced the levels of pro-inflammatory cytokines (TNF-α and IL-6), and increased the anti-inflammatory cytokine IL-10, indicating potent anti-infective and immunomodulatory functions. Overall, this work presents a multifunctional CSFe-incorporated hydrogel system that integrates antibacterial, anti-inflammatory, and tissue-regenerative properties, offering a promising strategy for infected wound healing and highlighting the potential of trivalent iron–polysaccharide coordination complexes in the development of advanced biomedical materials. Full article

Hydrocolloids are an extremely diverse and valuable group of materials, with various sources, properties and applications in many industries. Increasingly, naturally sourced colloids have gained the interest of the scientific world for their bio-availability, eco-friendliness and bio-degradability. This, coupled with emerging “green” extraction methods and modifying techniques, opens a wide range of uses. Pectin is a well-known, natural and abundant biomaterial, a heterogeneous anionic polysaccharide with vast applications in the food and pharmaceutical industries. Traditionally used in the food sector as a gelling agent and thickener, it is considered safe for human consumption. Pectin has found new applications in the pharmaceutical and medical worlds due to its complex structure, and it provides variety in its properties. This paper brings together information about this polysaccharide’s genuine usefulness in the context of growing interest for naturally sourced polymers, the reduction in wasteful industrial practices and environmental protection. Full article

Soil salinization poses an escalating threat to global crop production. Extracellular polysaccharides (EPSs) secreted by plant growth-promoting rhizobacteria have the potential to improve the salt tolerance of crops. Here, we tested the effects of Pantoea alhagi NX-11 EPSs on the growth, physiological traits, and root proteomic profiles of rice under salt stress. We found that NX-11 EPSs effectively increased the salt tolerance of rice in soil, with 50 mg/kg EPS exhibiting the strongest plant growth-promoting effect. This effect was associated with increased the K⁺/Na⁺ ratio and soluble protein content in roots induced by NX-11 EPSs as well as reduced stomatal aperture and transpiration rate in leaves. Proteomic analyses revealed that NX-11 EPSs markedly changed the protein profiles of roots. Specifically, proteins associated with cyanoamino acid metabolism, glycolysis/gluconeogenesis, and fatty acid degradation were downregulated. Together, these results suggest that NX-11 EPSs improve rice performance under salt stress, accompanied by changes in physiological traits and root protein profiles. Full article

Lentinula edodes (Berk.) Pegler, also known as Shiitake, is one of the most popular edible mushroom species containing high contents of polysaccharides, proteins and unique aroma, widely cultivated in China, Japan and Korea. A series of studies has been carried out on the extraction and active effect of the L. edodes polysaccharides, but the molecular mechanisms involved in the protein expression profiles during the whole life cycle are relatively unclear. This study employed an iTRAQ-MS/MS proteomic approach, combined with real-time quantitative PCR (qRT-PCR) and enzyme activity assays, to systematically analyze the protein expression profiles and their relationship with lignocellulose degradation in L. edodes across four key developmental stages: mycelia (SF), brown film formation (BF), primordia (YF), and fruiting bodies (MF). A total of 2043 proteins were identified, with 1188 being differentially expressed proteins (DEPs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that metabolic processes, carbohydrate metabolism, and related pathways were significantly active during development. The study specifically focused on carbohydrate-active enzymes (CAZymes), identifying 197 CAZyme proteins classified into 78 families. Key families such as glycoside hydrolases (GHs) and carbohydrate esterases (CEs) played crucial roles in lignocellulose degradation. The enzymatic activities of major lignin-degrading enzymes (laccase, manganese peroxidase, and lignin peroxidase) were dynamically regulated across the developmental stages. qRT-PCR results largely corroborated the proteomic data, confirming the reliability of the protein expression profiles. This study provides a comprehensive, stage-resolved proteomic landscape of lignocellulose degradation during L. edodes development, revealing species-specific temporal dynamics, offering a valuable basis for understanding its growth and development, with implications for edible fungus cultivation and biomass conversion applications. Full article

Acidified milk drinks (AMDs) are susceptible to protein aggregation and phase separation during production and storage, and xanthan gum (XG) is limited in application due to poor compatibility with milk proteins under acidic conditions. This study sought to improve the stabilizing performance of XG in AMDs through TEMPO-mediated oxidation. A series of oxidized xanthan gum (OXG) with different oxidation degrees were prepared by the TEMPO/NaClO/NaBr system, whose physicochemical properties were characterized, and the stabilizing effect and mechanism in AMDs were investigated. The results showed that high-degree OXG significantly improved the stability of AMDs, with the centrifugal sedimentation rate reduced from 8.93% to 2.22% and the zeta potential decreased from −32.6 mV to −37.9 mV, achieving a stabilizing effect comparable to that of sodium carboxymethyl cellulose (CMC). OXG could form uniform protein–polysaccharide aggregates with milk proteins, which may help inhibit phase separation. This study confirms that TEMPO oxidation can directionally regulate the structure and physicochemical properties of XG, enhancing its stabilizing effect in AMDs, which provides a new technical approach and theoretical basis for polysaccharide modification and the stabilization of acidic protein drinks. Full article

A new strategy to reduce the morbidity and mortality associated with invasive Streptococcus agalactiae (Streptococcus group B, GBS) diseases encompasses the development of vaccines. Candidate vaccines at different stages of clinical trials have been developed on capsular polysaccharides or protein antigens. We studied 328 GBS isolates identified using routine microbiological tests, latex-agglutination, and PCRs. The samples were categorised into two main groups: vaginal (69.2%) and extra-vaginal (30.8%). The molecular serotyping and target gene factors were determined using singleplex or multiplex PCRs. The most common serotypes identified were Ia (24.7%), V (22.0%), and III (18.9%). Serotypes I–V constituted a total of 89.0%. The non-typeable were 9.8%. The frequency of genes included in the recombinant GBS-NN (rib + bca) and GBS-NN2 (epsilon + alp2/3) vaccines were 54.3% and 40.8%. We noted a significant prevalence in the distribution of serotypes II, III, and non-typeable in GBS-NN, whereas serotypes Ia and IV were predominant in GBS-NN2. The serotype prevalence identified in our research was consistent with the data from our region and confirmed the predominance of the six main serotypes included in the hexavalent conjugated vaccine. We highlighted the importance of the combined administration of both protein vaccines, ensuring optimal vaccine coverage. Full article

Brewer’s spent grain (BSG) is an abundant lignocellulosic by-product whose valorization can support circular bioeconomy strategies. This study evaluated BSG bioconversion by Aspergillus oryzae ATCC 10124 under solid-state fermentation (SSF) to produce lignocellulolytic enzymes and release second-generation (2G) sugars relevant to biorefinery applications. SSF was monitored over 0–10 days, and FPase, endo-cellulase, β-glucosidase, xylanase, mannanase, amylase, and ligninolytic enzyme activities were quantified. Enzymatic crude extracts were further assessed in SDS-PAGE analysis. Glucose, cellobiose, xylose and arabinose release and consumption were tracked throughout fermentation, and substrate transformation was supported by FTIR. The secretome exhibited a predominantly hydrolytic profile, with maximal hemicellulolytic and cellulolytic activity around days 2–4, as well as sustained amylase activity. Ligninolytic activity was not detected. Sugar profiles indicated rapid early hydrolysis of glucose, followed by progressive pentose release. The stabilization and decline were consistent with fungal uptake. Changes in the carbohydrate fingerprint and SDS–PAGE banding supported structural polysaccharide remodeling and hydrolytic protein secretion. Thus, this SSF platform confirmed certain potential for low-cost cellulolytic and hemicellulolytic enzyme generation. However, because sugar accumulation was temporary and followed by consumption, this system is best interpreted as a biological pretreatment and enzyme-generation step that supports subsequent downstream valorization. Full article

Bacterial biofilms are structured microbial communities enclosed within a self-produced extracellular polymeric substance matrix composed of polysaccharides, proteins, extracellular DNA, and lipids. This matrix promotes adhesion, structural stability, and the development of heterogeneous microenvironments that restrict antimicrobial penetration and shield bacteria from host immune responses. As a result, biofilms are major contributors to chronic, recurrent, device-related, and difficult-to-treat infections, posing a major challenge for clinical management and antimicrobial stewardship. This review summarizes current understandings of biofilm biology, its clinical relevance, including the stages of biofilm development, the composition and protective roles of the matrix, and the physiological heterogeneity that arises during maturation. It also examines key mechanisms underlying biofilm tolerance and resistance, such as limited antibiotic diffusion, and sequestration, enzymatic inactivation, efflux pump upregulation, persister cell formation, and horizontal gene transfer. In addition, it highlights important clinical settings in which biofilms are implicated, including cystic fibrosis, chronic wounds, osteomyelitis, implant- or device-associated infections, and breast implant illness, in which persistent implant-associated biofilms and the resulting chronic inflammatory milieu have been hypothesized to contribute to local and systemic manifestations in a subset of patients. The review further discusses conventional and emerging approaches for biofilm detection alongwith real-time monitoring. Biofilm-associated infections remain difficult to eradicate because persistence is driven by multiple interconnected protective mechanisms. Effective management therefore requires integrated strategies that combine accurate detection with multifaceted therapies, including antibiotics alongside matrix-disrupting enzymes, quorum-sensing inhibitors, bacteriophages, metabolic reactivators, and nanotechnology-based delivery systems. Advances in multi-omics and system-level modeling will be essential for developing next-generation strategies to prevent, monitor, and treat biofilm-associated disease. Full article

Background: Beets are enriched in bioactive compounds with beneficial effects on cardiovascular function. Nitrate is a precursor for nitric oxide synthesis, exhibiting an effect on cardiomyocytes and myocardial ischemia/reperfusion, improving endothelial function and reducing arterial stiffness. Betanin, saponins and phenolic compounds, other beet compounds, can limit the generation of reactive oxygen species and modulate gene expression. However, it has been a challenge to develop beetroot formulations for the oral administration of these compounds while preserving pleasant sensory characteristics. Objective: The objective of this study was to develop an innovative dairy–beetroot powder drink, microencapsulated in polysaccharides, i.e., maltodextrin, cassava starch or a combination of both, that could be easily reconstituted. Key Results: The microencapsulated formulation following freeze-drying displayed low water activity (<0.30) and high solubility (>90%), with rapid dispersion in aqueous medium. Fourier transform infrared spectroscopy confirmed the preservation of functional groups from the dairy base and sugar beetroots. Thermogravimetry analyses pointed out a slight increase in thermal stability for the powder formulation. The microencapsulation efficiency of betalains reached 81% in the powder formulation that combined cassava starch and maltodextrin as encapsulation agents. The novel dairy–beetroot powder drink can be stored at room temperature, ensuring microbiological safety and preserving good sensory acceptance. Conclusions: Dairy–beetroot powder microcapsules emerge as an efficient food strategy to provide bioaccessible dietary nitrate and antioxidant compounds, overcoming flavor and stability limitations but still aiding in terms of its vascular and hemodynamic-protective effects. Full article

This study investigates the extraction of pectic polysaccharides from rapeseed meal (RSM) using both conventional and enzyme-assisted techniques, and the obtained pectic polysaccharide fractions will be used later to produce prebiotic pectic oligosaccharides (POS). A two-step process was developed, involving enzymatic treatment with Alcalase^® 2.4 L for 2 h and Cellic^® CTec3 HS preparations for 24 h, followed by ammonium oxalate extraction, which effectively isolated two pectic polysaccharide-enriched fractions: PP-EAE (first step) and the resulting Ca-bound pectic polysaccharides fraction (CaPP-EAE) (second step). Both fractions exhibited a bimodal molecular weight profile, indicative of the presence of long-chain polysaccharides alongside oligosaccharides. CaPP-EAE compositional analysis revealed that the fraction contained 56.8% galacturonic acid (GalA), low methyl-esterified (LM) pectins with 53.2% homogalacturonan (HG) and 30.2% rhamnogalacturonan I (RG-I) domains, featuring side chains of arabinan, arabinogalactan, and galactan. Subsequent enzymatic treatment with 0.5% (v/v) of Pectinex^® Ultra Passover for 30 min transformed these fragments into a mixture of short-chain POS. Importantly, the produced short-chain POS fraction demonstrated enhanced prebiotic activity, particularly for bacterial strains of the family Lactobacillaceae, compared to a yeast strain. These findings provide a sustainable, biorefinery-compatible approach for extracting and modifying RSM polysaccharides, supporting the development of structurally defined POS as novel prebiotics. Full article

This study aimed to evaluate how hydration temperature, rotational speed, and screw restriction influence the extraction efficiency, physicochemical characteristics, and monosaccharide composition of chia seed mucilage (CSM). Optimal extraction conditions (43.7 Hz, 100% screw restriction and 50 °C) yielded an extraction efficiency of 65.69% and a mucilage yield of 7.66%, producing a material with an average particle size of 15.28 μm, a ζ-potential of 9.7 mV, and weak-gel rheological behavior. Structural analyses confirmed the absence of insoluble fiber and revealed crystalline phases including MgO, Ca₅P₈, K₂S, K₄P₆, and CaCO₃, along with typical polysaccharide functional groups (–OH, –CH, C=O, COO⁻, C–O). Moderate hydration temperature combined with controlled mechanical conditions favored the release of mucilage enriched in xylose, glucose, and arabinose, which are characteristic of seed coat polysaccharides. In contrast, minimal mechanical action or excessive seed disruption shifted the monosaccharide profile toward cell wall structural carbohydrates, indicating reduced mucilage purity. Elevated hydration temperature (75 °C) enhanced the solubilization of uronic acids and arabinose, suggesting increased extraction of acidic polysaccharide fractions associated with the seed coat matrix. These findings demonstrate that extraction parameters strongly determine CSM composition, structural integrity, and functional attributes. The results provide a basis for tailoring chia-derived polysaccharides for applications in hydrocolloid systems, bio-based materials, and functional polymer formulations. Full article

Background/Objectives: Parkinson’s disease (PD) is a progressive neurodegenerative disorder that poses a substantial threat to global human health. Yam (Dioscorea opposita Thunb.) is a traditional medicinal and edible plant that has long been used in Asia, Africa, and the Caribbean. Its major bioactive components, such as dioscin and polysaccharides, have been reported to exhibit neuroprotective effects; however, the impact of dietary yam on PD progression remains to be elucidated. Therefore, we sought to evaluate its neuroprotective potential and the underlying mechanisms in 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP)-induced PD mice. Methods: Mice received six-week dietary yam supplementation. Behavioral, histological, and neurochemical analyses were performed to assess motor function, dopaminergic neuron integrity, and dopamine levels. Gut microbiota and metabolic profiles were analyzed using 16S rRNA gene sequencing and non-targeted metabolomics. Transcriptomic sequencing and Western blot analysis of the substantia nigra pars compacta (SNc) were conducted to investigate molecular mechanisms, and integrative multi-omics analysis was applied to explore microbiota–metabolite–host interactions. Results: Yam supplementation improved motor function, preserved nigrostriatal dopaminergic neurons, and restored striatal dopamine levels in PD mice. Notably, yam was associated with the maintenance of intestinal homeostasis by strengthening barrier integrity and enriching beneficial taxa, including Ileibacterium, Lachnospiraceae NK4A136 group, and Blautia. Consistently, yam also elevated neuroprotective purines and amino acids, including inosine, xanthine, and succinic acid. At the molecular level, yam treatment modulated mitochondrial oxidative phosphorylation by increasing PGC-1α and COX7c expression, and reduced inflammasome-related neuroinflammatory signaling. Integrative modeling showed significant associations between yam-modulated genes and PD-related indices with microbiota and metabolites. Conclusion: These findings suggest that yam may represent a potential dietary strategy for alleviating PD-related neurodegeneration by modulating the microbiota–gut–brain axis. Full article