Biopolymers (BPs), obtained from urban and agricultural wastes, are known as active principles to manufacture ready-for-use finished products in several sectors of the agriculture and chemical industries. These findings prospect a biowaste-based refinery producing chemical specialities to replace products derived from fossil feedstock. The present paper reports new materials containing BPs. Composite granules containing Poly(Butylene Adipate-Co-Terephthalate (PBAT) as a matrix and BPs as fillers are manufactured by twin-screw extrusion. The granules are used to make single-layer PBAT-BP mulch films by single-screw extrusion and three-layer Starch-PBAT-BP films by blown co-extrusion. The films are tested for mechanical properties, and for structural stability and effects in the in vitro cress germination and the in-field horticulture. The results show that both the films' effects on plant performance and the films' structural degradation are regulated by the BP and polymeric matrix release kinetics in the operational germination medium or the field soil, and in turn, that the kinetics depend on the mulch film structural features. The horticulture trials prove that the three-layer mulch films have adequate mechanical strength (25 MPa maximum tensile strength and 520% elongation at break) and about 6 months lifespan to maintain and/or improve the soil protection and crop production (17 t/ha) over the plant seasonal cycle. These findings widen the range of renewable chemical specialities potentially producible by the envisioned biowaste-based refinery.
Understanding the aqueous solvation of simple ions, small molecules, and complex biopolymers is fundamental in the physical and life sciences. Terahertz spectroscopy allows one to directly interrogate the underlying collective hydrogen-bond network dynamics by probing the corresponding intermolecular vibrations in the THz frequency regime. Most notably, this provides crucial insights into how the dynamical hydrogen-bonded water network gets perturbed by hosting solute species, for instance in terms of solvation shells or extended hydration layering. Here, we present a comprehensive, critical survey of recent developments in theoretical THz spectroscopy, rigorously anchored in statistical mechanics and electronic structure theory, while keeping our focus on bulk water and aqueous solutions when it comes to applications. At the heart of our review are those methods that assign THz spectral features to specific molecular motion in terms of low-frequency intermolecular dynamics, thereby greatly extending the paradigm established decades ago for interpreting mid-infrared spectra based on high-frequency intramolecular modes. We classify these approaches systematically into two families─mode-based and topological/spatial decomposition schemes─and compare their respective assumptions, strengths, limitations, and computational cost to provide a practical roadmap for choosing the appropriate method for a given problem.
Extracellular polymeric substances (EPSs) are high-molecular-weight biopolymers secreted by microorganisms, showing great potential for bioremediation. However, comprehensive analyses of the development context and quantitative research on the overall trends of EPSs in bioremediation are lacking. This study conducted a systematic bibliometric analysis of microbial EPS research using VOSviewer and CiteSpace. Keyword burst and thematic evolution analysis indicate a distinct thematic shift: early research focused on "structural characterization and adsorption mechanisms of EPSs", whereas current hotspots highlight interactions with emerging pollutants (e.g., microplastics, antibiotics, and antibiotic resistance genes (ARGs)). EPSs significantly influence the environmental fate and removal efficiency of emerging pollutants through multiple pathways, including physical adsorption, chemical complexation, photocatalytic degradation, and electron transfer. For microplastic remediation, EPSs mediate hetero-aggregation, surface modification, and biodegradation processes. In antibiotic removal, EPSs function through biosorption, biodegradation, and photosensitized degradation. Regarding the mitigation of ARGs, EPSs can either suppress or facilitate their horizontal gene transfer, depending on their composition and environmental conditions. Additionally, as electroactive medium, EPSs play a crucial role in facilitating electron transfer, enhancing nitrogen removal, and promoting heavy metals reduction. This study systematically reviewed the current status and research hotspots of EPSs in bioremediation. However, practical applicability remains constrained by challenges such as low production yield and high costs. Future directions to address these limitations are also outlined to guide further development.
Natural rubber is an important biopolymer utilized in more than 4,000 commercial products. Nevertheless, the accumulation of waste rubber poses a significant environmental challenge due to its resistance to natural degradation. The present study sought to isolate and identify fungi from discarded rubber materials and assess their potential involvement in the early-stage surface deterioration of natural rubber. An initial screening of 69 fungal strains for extracellular enzyme production, including esterases, lipases, proteases, and laccases, was conducted. Following preliminary qualitative assays, 36 enzyme-producing isolates were further assessed for their capacity to modify natural rubber using rubber disc assays. Four isolates (L-12A, L-25, L-33, and T-21) showed measurable surface alterations associated with early-stage deterioration, as evidenced by limited mass loss, positive Schiff's reagent staining, and surface alterations observed through scanning electron microscopy (SEM). After 2 months of incubation, rubber mass loss ranged from 0.77% ± 0.27% to 1.24% ± 0.25%. Schiff's reagent staining indicated oxidative modification of the rubber surface, and SEM analysis revealed surface cracking, erosion-like features, and fungal colonization. Combined morphological characteristics and multilocus phylogenetic analyses identified these strains as Neocosmospora bostrycoides (L-12A), Neocosmospora sp. (T-21), Paracremonium laticis (L-25), and Schizophyllum commune (L-33). Descriptions, illustrations, and phylogenetic analyses of the four species are presented. This study provides preliminary evidence that these fungi may contribute to early-stage surface deterioration and oxidative modification of natural rubber.
Bees are social insects belonging to the Apidae family, which includes stingless bees, honeybees, and related groups. Their ability to produce various products, such as bee bread, bee pollen, propolis, beeswax, and royal jelly, has attracted scientific interest due to their nutritional composition, biological activities, and potential therapeutic value. Bee bread is a fermented mixture of pollen, honey, and salivary bee enzymes, rich in bioactive compounds with potential benefits for reproductive health and other biological activities. However, bee bread remains one of the least explored bee products in relation to reproductive health. This narrative review summarises the potential health benefits of bee bread from stingless bees for male and female reproductive function. Evidence from animal studies shows that bee bread has promising effects on reproductive function, possibly through its antioxidant properties, support of spermatogenesis and steroidogenesis, improvement of pregnancy outcomes, enhancement of ovarian function, regulation of metabolism, and modulation of inflammatory activity. Findings from animal studies suggest potential benefits for both male and female reproductive health. However, well-designed randomised controlled trials are needed to evaluate its efficacy, optimal dosage, safety profile, and long-term effects on reproductive outcomes in both males and females.
The increasing demand for sustainable bio-resources has spurred interest in underutilized species like Sonneratia apetala, a mangrove with traditionally consumed fruits. This study provides a comprehensive biochemical and microbiological profile of S. apetala fruit and its derived products (jam, jelly, and pickle), integrating nutritional valorization with safety assessment. Pectin was extracted via acid hydrolysis and ethanol precipitation, yielding 2% with high purity (99.9%), confirmed by FT-IR and NMR spectroscopy. Vitamin C was isolated with a 1% yield and 99.9% purity, verified by HPLC and NMR. Amino acid profiling revealed the raw fruit was rich in essential amino acids, notably histidine (26.6 mg/g). Processing significantly degraded most amino acids, though histidine showed remarkable stability (16.4-17.8 mg/g). Antioxidant analysis demonstrated exceptional activity; the ethyl acetate root extract exhibited a potent DPPH IC₅₀ of 0.74 µg/mL, surpassing many synthetic antioxidants, alongside high Total Phenolic and Flavonoid Contents (555.8 mg GAE/100g DW and 240.6 mg QE/100g DW, respectively). A strong correlation was observed between phenolic content and antioxidant capacity. Crucially, fungal screening showed no detectable growth (<10 CFU/mL) in all samples, indicating product safety and stability. In conclusion, S. apetala fruit is a promising source of high-quality pectin, vitamin C, and potent antioxidants, with processed products being microbiologically stable. This research positions S. apetala as a valuable, multi-purpose species for nutraceutical and food industrial applications, with recommendations for further investigation into specific root antioxidants and scaled-up pectin extraction.
Background and Objectives: Corneal collagen cross-linking (CXL) halts keratoconus progression, yet potential differences between conventional and accelerated protocols at one year remain uncertain. We analyzed the completed 12-month follow-up of a previously reported 6-month cohort to compare conventional (3 mW/cm2 × 30 min; CXL 30) versus accelerated (9 mW/cm2 × 10 min; CXL 10) CXL, interpreting outcomes within the ABCD framework alongside Kmax and curvature radii. Materials and Methods: In this single-center retrospective longitudinal analysis of prospectively collected routine clinical data, 22 eyes were included, with assessments performed at baseline and at 1, 3, 6, and 12 months of follow-up. Evaluated outcomes comprised ABCD stages (A-D), anterior and posterior radius of curvature (ARC and PRC), Kmax, pachymetric and elevation indices, as well as UDVA and BCVA. Within-group change used Friedman with Wilcoxon post hoc; between-group differences used Mann-Whitney (α = 0.05). Results: Both protocols resulted in significant visual improvement and Kmax reduction at 12 months (overall time effect: CXL 30 p < 0.001; CXL 10 p = 0.026). Median Kmax decreased 56.5 → 52.3 D (CXL 30) and 59.3 → 58.3 D (CXL 10). UDVA improved 0.2 → 0.6 (CXL 30) and 0.2 → 0.3 (CXL 10); BCVA 0.4 → 0.8 (CXL 30) and 0.2 → 0.5 (CXL 10). Tomographic analysis showed predominantly anterior changes, with a significant decrease in A stage in the CXL 30 group and an increase in ARC in both groups, more pronounced in CXL 30. In the late 6 → 12-month window, posterior metrics (PRC and posterior elevation) were largely stable; raw PRC change did not reach significance. Conclusions: Conventional and accelerated CXL both stabilized keratoconus at one year with meaningful functional gains. Beyond 6 months, remodeling was predominantly anterior; within-group findings suggested a more pronounced anterior tomographic response in the CXL 30 group. The 12-month visit may be useful for reassessing stability after CXL, although this study was not designed to determine optimal retreatment timing or optical rehabilitation strategy. Longer-term studies with standardized biomechanical and densitometric endpoints are warranted to assess durability and refine protocol selection.
This preliminary study characterises type I collagen in the digestive system of the greater weever (Trachinus draco L.) by integrating histochemical and biochemical techniques. To the best of our knowledge, this study represents the first baseline mapping of type I collagen within the gastrointestinal tract of this species. Mallory staining and indirect immunofluorescence confirmed collagen presence across the oesophagus, stomach, and intestine. The histochemical quantification of the fluorescent area (100 measurements per organ across 15 fish specimens) showed no significant differences (p = 0.1315), indicating a uniform spatial distribution. However, biochemical analysis via hydroxyproline assay and a two-way ANOVA revealed significant differences in collagen content among organs (p = 0.0308). The stomach yielded the highest concentration (4.199 µg/mg), significantly exceeding that of the intestine (1.713 µg/mg; Šídák's post hoc, p = 0.0300). This discrepancy suggests that the higher gastric content is due to greater fibre density rather than distribution area. SDS-PAGE and Western blot confirmed protein molecular weights of 100-130 kDa, corresponding to α1 and α2 chains typical of type I collagen. The combination of these histochemical and biochemical methods effectively detects and characterises collagen in fish gastrointestinal by-products. By introducing T. draco as a novel subject in this context, these findings provide essential baseline anatomical and histological data and offer a clear scientific justification for the biotechnological valorisation of unutilised commercial fishing by-products, fully aligning with sustainable marine circular economy principles.
Troponin T is a molecular marker of cardiomyocyte injury, whereas left ventricular ejection fraction (LVEF) and tricuspid regurgitation velocity (TRV) reflect downstream ventricular and cardiopulmonary measures. This study evaluated whether synchronized troponin T and echocardiographic data can identify mortality risk in critically ill patients with heart failure, while separating statistical association from clinically meaningful incremental discrimination. Adult intensive care unit admissions with heart failure diagnoses were identified from MIMIC-IV and MIMIC-IV-ECHO. The primary endpoint was 28-day all-cause mortality; one-year mortality was secondary. Multivariable Cox models were adjusted for demographics, comorbidity, illness severity, organ support, and laboratory covariates. Restricted cubic splines, proportional hazards diagnostics, variance inflation factors, prespecified subgroup interaction tests, complete-case analyses, and multiple imputation sensitivity analyses were performed. The final cohort included 4362 patients, and 1072 patients (24.6%) died within 28 days. In the primary complete-case Cox model (n = 2087; 659 deaths), higher log-transformed troponin T was associated with higher 28-day mortality (hazard ratio [HR], 1.09; 95% confidence interval [CI], 1.03-1.15; p = 0.003), and higher LVEF was associated with lower mortality (HR per percentage point, 0.99; 95% CI, 0.99-1.00; p = 0.004). After severity and organ-support covariates were entered, troponin T and LVEF produced statistically detectable but very small C-statistic gains. Measurable TRV was available in 1546 patients and was associated with mortality in that subset (HR, 1.28; 95% CI, 1.08-1.52; p = 0.005). Troponin T, LVEF, and TRV were associated with mortality in ICU heart failure. Their contribution was best interpreted as risk enrichment within a clinical severity framework rather than a stand-alone decision rule.
Lignin is an abundant aromatic biopolymer generated as a major by-product in lignocellulosic biorefineries, and its efficient valorization is essential for improving process sustainability and economic viability. Among current upgrading strategies, the conversion of lignin into lignin-derived biochar (LDB) has emerged as a promising route because of its high carbon yield, scalable production, and tunable physicochemical properties. This review examines the relationships between lignin structure, thermochemical conversion pathways, and the resulting properties of LDB materials within biorefinery systems. The influence of different technical lignins and conversion routes, including pyrolysis and hydrothermal carbonization, is critically discussed together with post-functionalization strategies. Particular attention is devoted to emerging applications in contaminant adsorption and controlled release systems for agrochemicals. The adsorption mechanisms governing pharmaceuticals, pesticides, microplastics, and PFAS removal are analyzed, while the dual role of LDB as both adsorbent and delivery platform is highlighted. Current limitations include lignin heterogeneity, lack of standardized evaluation protocols, and insufficient validation under realistic environmental conditions. Overall, LDB represents a versatile and scalable platform for lignin valorization and sustainable material design within circular bioeconomy frameworks.
Diabetes is considered a serious chronic disease that carries a high risk of significant complications. Recently, the utilization of natural hypoglycemic plants has been increasing for the management of diabetes due to their biosafety, low side effects, and economical features. Opuntia ficus-indica (OFI) fruit has various pharmacological properties as a source of bioactive compounds, which have shown effectiveness in diabetes treatment. Fruits peel mucilage (FM) was extracted from OFI fruit for the green synthesis of selenium nanoparticles (SeNPs), which were then encapsulated with chitosan (Ch) to generate nanocomposites (Ch/FM/SeNPs). This study was carried out to evaluate the antidiabetic activity of nanocomposites (Ch/FM/SeNPs) against streptozotocin (STZ)-induced diabetic rats. Accordingly, rats were divided into six groups, namely, normal control (GI), diabetic control (GII), treatment groups (GIII, GIV, and GV) administered nanocomposite powder (Ch/FM/SeNPs) with concentrations 0.1, 0.2, and 0.3 mg/kg, respectively, and (GVI) received glibenclamide at a dose of 5 mg/kg for 28 days. At the end of the treatment, the rats were subjected to analysis including body weight, blood glucose level, lipid profile, and hepatic and renal function tests. The nanocomposite (Ch/FM/SeNPs) had an average particle size (PS) of 81.18 nm and a positive charge (+30.11 mV), with an equivalent ratio of Ch and FM/SeNPs (1:1). The average particle size of FM/SeNPs was 6.34 nm with a negative charge (-25.93 mV). The morphological characteristics indicated semi-spherical shapes of the nanocomposites (NCs) and stabilization and homogenous distribution of SeNPs within the polymer nanocomposites. The results indicated that treatment of diabetic rats with nanocomposite powder (Ch/FM/SeNPs) at a concentration of 0.3 mg/kg resulted in significant increases in body weight, along with significant reductions in blood glucose levels and improvement in biological parameters, lipid profile, and hepatic and renal function. Promisingly, the nanocomposite (Ch/FM/SeNPs) can be used as a hypoglycemic compound; therefore, it could be recommended for the development of antidiabetic drugs.
The problem of chromium contamination, especially Cr(VI), in acidic wastewater has drawn significant attention, requiring effective and sustainable remediation measures. In this study, tannic-acid/Fe3O4-modified corn straw biochar (Fe-TA-CSB) is prepared by a grinding-calcination method to remove Cr(VI). The factors influencing the removal effect of Fe-TA-CSB are investigated through static adsorption experiments. The removal mechanism is explored by combining adsorption kinetics, isothermal adsorption, and thermodynamics, as well as characterization methods. The results show that the removal efficiency of Cr(VI) increases with the increase in pH, contact time (t), and solid-liquid ratio (m/v), but decreases with the increase in initial concentration (C0). Under optimal conditions of TA/Fe3O4 mass ratio = 12.5%, pH = 3.0, m/v = 1.0 g/L, and C0 = 10 mg/L, the removal efficiency value is 94.02%, which is approximately 81.44% after four adsorption-desorption cycles. The adsorption behavior is fitted well by the Sips isotherm model and Elovich kinetics model, suggesting the adsorption process of heterogeneous monolayer chemisorption. The removal mechanism of Cr(VI) by Fe-TA-CSB involves electrostatic interaction with Cr(VI), reduction in Cr(VI) to Cr(III) through C-O and Fe(II), and complexation of reduced Cr(III) with the introduced Fe-O and phenolic hydroxyl groups. Fe-TA-CSB is an environmentally friendly and renewable adsorbent with good potential for the treatment of acidic wastewater.
Background: Uridine diphosphate glucose (UDP-Glc) is one of the key substrates for the biosynthesis of gallotannins in plants. UDP-glucose dehydrogenase (UGD) catalyzes the irreversible oxidation of UDP-Glc to UDP-glucuronic acid (UDP-GlcA), thus affecting the biosynthesis and accumulation of gallotannins in the Chinese gallnut. Methods and Results: In this study, we identified three members of the RcUGD family from the Rhus chinensis genome. Protein sequence alignment revealed that all three RcUGDs possess the conserved NAD+ coenzyme binding motif GAGYVGG and the catalytic motif GFGGSCFQKDIL. qRT-PCR analysis revealed that the expression levels of RcUGD3 in stem and root tissues were respectively 10-fold and 13-fold greater than that in the leaves, in which gallotannin accumulation was higher. RcUGD3 expression level declined by 63% during early (24 d) gallnut development, suggesting an inverse relationship between RcUGD3 expression level and gallotannin biosynthesis. In addition, subcellular localization analysis using the tobacco transient transformation system showed that RcUGD proteins are broadly distributed throughout the cell. Moreover, an in vitro enzyme activity assay indicated that the recombinant RcUGD3 protein catalyzed UDP-Glc to produce UDP-GlcA as shown by HPLC. Taken together, our results suggested that RcUGD3 protein is responsible for UDP-Glc degradation and probably plays a regulatory role in gallotannin biosynthesis in the Chinese gallnut. Conclusions: This study lays a foundation for further elucidating the function and expression regulation mechanism of the RcUGD gene family and provides new insights for the super-accumulation mechanisms of gallotannins in Chinese gallnuts.
Intracranial aneurysms (IAs) represent a major clinical concern due to their risk of rupture and the resulting morbidity and mortality. Both environmental and genetic factors contribute to IA susceptibility, yet the genetic causes of IA remain poorly understood. We previously identified several single nucleotide variants (SNVs) in collagen XXII (COL22A1) in affected individuals with IA. However, the functional impact of these variants has not been determined, and it remains unclear whether and how they increase IA susceptibility. Here, we tested the functional effect of these variants in a zebrafish embryo model. Inducible overexpression of six human COL22A1 SNVs increased the incidence of cranial hemorrhage in zebrafish embryos, while overexpression of wild-type COL22A1 had no significant effect. Overexpression of DNA construct encoding COL22A1 P989L variant disrupted intracranial vascular architecture, leading to reduced vessel length, altered vascular surface parameters, and abnormal arterial patterning. Overexpression of the P989L SNV also caused pronounced vascular leakage, reduced pericyte number, and decreased expression of the tight junction proteins Claudin-5 and ZO-1. P989L SNV overexpression was also associated with increased expression of the endoplasmic reticulum stress marker hspa5. In silico modeling suggested that the P989L variant likely perturbs triple-helix formation in COL22A1, thereby causing protein misfolding and compromising its function. Together, these findings demonstrate the deleterious effects of IA-associated COL22A1 variants on vascular function and stability and suggest that these variants may increase the incidence of IA in humans.
Citrus processing generates large amounts of peel residues rich in pectic polysaccharides that can be valorized through eco-friendly extraction methods. This study evaluated how citric acid extraction conditions (pH 1.46-2.64, 51-96 °C, 20-70 min) influence the yield, composition, and functional properties of pectin obtained from orange peel. A central composite design (CCD) assessed the effects of pH, temperature, and time on pectin yield, degree of esterification (DE), and galacturonic acid (GalA) content. Pectin obtained under conditions maximizing each response was further characterized by structural, thermal, rheological, and functional properties. The maximum values obtained were 26.5% yield (96 °C, 70 min, pH 1.46), 84.1% GalA (74 °C, 42 min, pH 2.17), and 67.0% DE (50 °C, 70 min, pH 1.46). High yield was favored by high temperature and low pH, whereas GalA was maximized under moderate conditions, although at low recovery (5.6%). GalA-optimized pectin showed higher gel hardness (641 g) and apparent viscosity (0.64 Pa·s) than yield-optimized pectin (122 g; 0.28 Pa·s). This study demonstrates that optimizing for yield, GalA, or DE produces structurally distinct pectin fractions with different functional properties rather than a single optimal extraction condition.
Wound infections due to antibiotic resistance pose a global public health problem. Phage therapy is a promising approach to address this issue. To improve localization, phage stability, delivery, and antibacterial performance, we propose polymer mix gel microbeads encapsulated with phages as a model for the delivery of phiKZ bacteriophage to combat Pseudomonas aeruginosa. Phages were loaded into the alginate pre-gel under magnetic stirring, with further cross-linking by chitosan and/or Ca2+ ions. The obtained gel microbeads were characterized using FTIR and Raman spectroscopy, and their cytotoxicity and antimicrobial properties were evaluated. This study demonstrated the efficient loading of high-titer phage lysate, achieving up to 99% encapsulation efficiency for alginate-chitosan microbeads. The key characteristics of the microbeads include stable physicochemical properties, slow but continuous phage release over 48 h in physiological saline, and low cytotoxicity. The phage-loaded microbeads demonstrated strong in vitro antimicrobial activity against P. aeruginosa PAO1, resulting in mean reductions of 6.9 log10 and 4.8 log10 CFU/mL for alginate and alginate-chitosan formulations, respectively. This corresponded to a decrease in bacterial concentration from approximately 1.1 × 1011 CFU/mL in untreated controls to 1.1 × 105 CFU/mL and 7.7 × 106 CFU/mL for alginate and alginate-chitosan formulations after 3 h of incubation.
Ring-opening polymerization (ROP) of β-lactones yields biodegradable and bioresorbable polyesters exhibiting potential utility in medicine and environmental protection. β-butyrolactone (BL) is especially interesting, as it yields polymers analogous to natural poly(3-hydroxybutyrates) produced by bacteria, fungi, and enzymes in nature. The biopolymer produced by these microorganisms is isotactic. While it can be synthesized biotechnologically through the bacterial fermentation of substrates, such as sucrose, corn, and sugar, laboratory production typically involves the ring-opening polymerization of BL. However, the latter process is mainly atactic, syndiotactic, or partly isotactic, and other β-substituted β-lactones are less well-known. Ring-opening polymerization is an excellent pathway for the production of poly(β-lactones). This critical review presents the different conditions required to synthesize poly(β-lactones) and a broad overview of the different kinds of ROPs, i.e., anionic, cationic, coordinative, supramolecular-based, and enzymatic processes. A great variety of initiators/catalysts have been studied, covering both metal-based and metal-free systems (organo- and biocatalysts). In this review, several mechanisms of β-lactone polymerization are presented and discussed, especially with regard to the processes' initiation steps.
The synthesis of reactive sucrose derivatives is of significant interest for the development of novel biocompatible polymers. In this study, an octa-substituted sucrose derivative containing isocyanate groups was synthesized via a urethane-forming reaction carried out in an aprotic solvent at the phase interface. This approach exhibits high selectivity and provides a target product yield of up to 60%. Subsequently, using the same reaction mechanism, the isocyanate derivative was converted into an octa-functional methacrylate derivative capable of forming three-dimensional cross-linked networks. The structures of both the intermediate and final products were confirmed by IR, 1H NMR, and mass spectrometry. The sucrose-based prepolymer was further evaluated in the formation of cross-linked structures for potential application as bone-substituting implants. Using various photocuring techniques, including two-photon 3D printing, both plates and microstructured scaffolds were fabricated. These structures exhibited high thermal stability, elastic properties comparable to those of bone tissue, and no toxic effects on cells.
Cyclodextrin glycosyltransferase (CGTase) is a highly valuable biocatalyst in industrial starch conversion, particularly for the synthesis of cyclic oligosaccharides. In this study, a CGTase, designated HfCGT, was cloned from Haloferax sp. and heterologously expressed in Escherichia coli. The recombinant enzyme was purified and biochemically characterized. HfCGT exhibited maximal catalytic activity at 70 °C and pH 8.0, tolerance to metal ions and EDTA, and enhanced activity in the presence of 1 M NaCl and Ca2+. High-performance liquid chromatography (HPLC) and high-resolution mass spectrometry (HRMS) analyses revealed that the starch products by HfCGT degradation were mainly large-ring cyclodextrins (LR-CDs) with polymerization degrees of 9 to 20. Altogether, the thermostability, haloalkaliphilic, and distinctive product profile make HfCGT a promising biocatalyst for pharmaceutical, food, and biotechnological applications.
Microbial community assembly is shaped by the nature of available resources, with labile carbon sources like glucose often expected to support low diversity due to rapid growth and competitive exclusion. In contrast, recalcitrant substrates like cellulose are thought to support higher diversity through slower growth and increased niche partitioning. In previous work, we showed that compost-derived microbial communities propagated on cellulose maintained high diversity over nearly a year. To determine whether such diversity is specific to recalcitrant substrates or reflects more general features of assembly, we tracked community dynamics in three environments-cellulose paper, cellulose broth and glucose-using daily 16S rRNA profiling. Communities maintained through four bi-weekly serial transfers, with five replicates per treatment, yielded a high-resolution dataset of over 800 samples. Despite originating from the same inoculum, communities diverged sharply in both taxonomic and functional composition. Cellulose environments yielded stable communities enriched in specialists, while glucose environments exhibited rapid succession and dominance by generalists. Surprisingly, all environments sustained comparably high levels of taxonomic diversity. Functional inference suggested extensive cross-feeding and resource salvaging in both cases. Our results reveal distinct assembly trajectories under simple carbon regimes and provide a foundation for future mechanistic study.