Search Results (121)

Background/Objectives: Postprandial hyperglycemia is a risk factor for diabetes and cardiovascular diseases, even in healthy individuals. Kanzaki mulberry leaf and water chestnut tea (MW tea), a blend of mulberry (Morus alba) leaves and water chestnut (Trapa japonica) leaves and husks, is rich in polyphenols and 1-deoxynojirimycin (DNJ) and may suppress postprandial glucose spikes, but evidence regarding its short-term daily intake is limited. This study aimed to evaluate the postprandial glycemic response and safety of two-week MW tea consumption using continuous glucose monitoring (CGM). Methods: We conducted a randomized, double-blind, placebo-controlled, two-period crossover trial involving 31 participants. Each intervention period lasted two weeks, separated by a one-week washout. Participants consumed either MW tea or a placebo before meals. Interstitial glucose levels were measured every 15 min using CGM. Postprandial glucose responses were recorded every 15 min for 180 min after a standardized meal on the first day of each period. The primary outcome was the coefficient of variation (CV) in glucose levels, calculated using data from the central 10 days of each intervention period. Safety was assessed using CGM-derived hypoglycemia metrics and blood test results. Results: The CV of glucose levels during the MW tea period was significantly lower than during the placebo period (mean difference: 0.02, p = 0.0006). A significant reduction in 1 h postprandial glucose area under the curve was also observed. No significant differences were found in hypoglycemia occurrence, liver/renal/inflammatory markers, or self-reported adverse symptoms. Notably, 1,5-anhydroglucitol (1,5-AG) levels significantly increased during MW tea intake, suggesting improved glycemic control. Conclusions: Short-term consumption of Kanzaki MW tea effectively suppressed postprandial glucose variability without safety concerns. These findings support MW tea as a promising natural supplement for glycemic management and the prevention of diabetes. Full article

Dual-physical modification is an eco-friendly and waste-free approach for enhancing the functionality of native starches compared with a single modification. In the present study, the individual and combined interrelating effects of hydrothermal (heat moisture (HM) with 15%, 20%, and 25% moisture) and non-thermal (ultrasonication (US) with 200, 400, and 600 power (W)) on the physical modification of Eleocharis tuberosa (Chinese water chestnut (CWCS)) starch were studied. Furthermore, their effects on the morphology, FTIR, XRD, crystallinity, thermal, pasting, swelling power, solubility, rheological characteristics, and in vitro digestibility of native and modified starches were investigated. The results indicated a consistent B-type structure of CWCS, with a significant decrease in the crystallinity (22.32 ± 0.04–28.76 ± 0.02%), which was linked with ΔH (19.65 ± 0.01–12.18 ± 0.06 Jg⁻¹) and amylose content (34.67 ± 0.07–40.73 ± 0.11%). The absorbance ratio 1048/1025 specified that the combination of HM-US compacted the short-range order degree up to 1.30 for HM25–US600-CWCS. The starch treated with HM, followed by the US, considerably amplified the setback, peak, and final viscosities compared with the HM-treated starch. The rheological analysis demonstrated that the fluidity of CWCS was enhanced (G′ > G″, tan δ < 1) by the synergistic effect of HM and US, increasing the resistivity toward deformation during paste development. The dual-modified starch exhibited a slower glucose release rate with increasing moisture (25%) during HM and 600 W during the US, with higher RS contents of 45.83 ± 0.28% and 43.09 ± 0.12%, respectively. Dual-physical modification exhibited a significant aptitude for modifying native starches structurally and functionally as a substitute for product formulation with a low glycemic index. Full article

Aquaculture effluents are a growing source of water pollution, releasing suspended solids, organic matter, nitrogen, and phosphorus into aquatic environments. Recirculating aquaculture systems (RASs) have emerged as a more sustainable solution, allowing water to be continuously treated and reused. Within RASs, coagulation–flocculation is a key treatment step due to its simplicity and effectiveness. Tannin-based coagulants have gained attention as natural alternatives to traditional chemical agents. Although natural coagulants have been studied in aquaculture, only a few works explore their use in continuous-flow systems. This study evaluates a chestnut shell-based (CS) coagulant applied in continuous mode for the post-treatment of aquaculture effluent. The performance of CS was compared with Tanfloc, aluminum sulfate, and ferric chloride in removing color and dissolved organic carbon (DOC). At natural pH (6.5) and 50 mg·L⁻¹, CS and Tanfloc achieved color removal of 61.0% and 65.5%, respectively, outperforming chemical coagulants. For DOC, Tanfloc and chemical coagulants removed 45–50%, while CS removed 32%. All coagulants removed over 90% of phosphorus, but nitrogen removal was limited (30–40%). These results highlight the potential of tannin-derived coagulants, particularly from agro-industrial residues, as sustainable solutions for aquaculture wastewater treatment in continuous systems. Full article

The CO₂ capture from flue gas using biomass-derived porous carbons presents an environmentally friendly and sustainable strategy for mitigating carbon emissions. However, the conventional fabrication of porous carbons often relies on highly corrosive activating agents like KOH and ZnCl₂, posing environmental and safety concerns. To address this challenge, in the present work sodium metaborate tetrahydrate (NaBO₂·4H₂O) has been utilized as an alternative, eco-friendly activating agent for the first time. Moreover, a water chestnut shell (WCS) is used as a sustainable precursor for boron-doped porous carbons with varied microporosity and boron concentration. It was found out that pyrolysis temperature significantly determines the textural features, elemental composition, and CO₂ adsorption capacity. With a narrow micropore volume of 0.27 cm³/g and a boron concentration of 0.79 at.% the representative adsorbent presents the maximum CO₂ adsorption (2.51 mmol/g at 25 °C, 1 bar) and a CO₂/N₂ selectivity of 18 in a 10:90 (v/v) ratio. Last but not least, the as-prepared B-doped carbon adsorbent possesses a remarkable cyclic stability over five cycles, fast kinetics (95% equilibrium in 6.5 min), a modest isosteric heat of adsorption (22–39 kJ/mol), and a dynamic capacity of 0.80 mmol/g under simulated flue gas conditions. This study serves as a valuable reference for the fabrication of B-doped carbons using an environmentally benign activating agent for CO₂ adsorption application. Full article

The quality and stability of honeys are strongly influenced by their chemical composition and physicochemical properties, which vary with botanical origin. This study examined the physicochemical and compositional properties of cotton, heather, orange, thyme, Christ’s thorn, and chestnut monofloral honey samples, as well as the kinetics of the creaming–crystallization process by monitoring rheological and color parameters. All samples had moisture content lower than the legislation limit (<20%) and a_w ≤ 0.60. Chestnut and heather honeys exhibited the highest electrical conductivity and darkest color. Fructose was the predominant sugar in all samples, with thyme having the highest content. Viscosity decreased exponentially with increasing moisture, with thyme honey being the most viscous. Principal component analysis showed distinct clustering of samples based on their compositional–physicochemical characteristics. Calorimetry revealed the water’s plasticization effect on honey solids, lowering their glass transition temperature, with the data fitting well to the Gordon–Taylor model. Rheometry indicated a Newtonian-like behavior for liquid honeys, evolving towards a pseudoplastic response upon creaming–crystallization. Cotton honey crystallized rapidly, thyme honey showed moderate crystallization propensity, while samples of heather honey gave a diverse response depending on composition. Overall, high glucose content and/or low fructose/glucose ratio promoted honey crystallization, leading to the formation of highly viscous-creamed honey preparations. Full article

Water pollution by toxic metals, especially by lead ions, is a serious environmental concern due to these metals’ persistence, bioaccumulation, and toxicity. Aiming to reduce metal concentrations to non-toxic levels, this study analyzed the removal of lead from water through adsorption with bio-adsorbents. The adsorbent potential of the following four lignocellulosic byproducts were tested: walnut and chestnut shells, pine wood, and burnt pine wood. Removal rates of 97–99% were achieved at optimized conditions, i.e., at a pH of approximately 7, adsorbent dose of 4 g L⁻¹, and 12 h of reaction. The BET specific surface area was between 1.74 and 4.85 m² g⁻¹. The pore size of the wood bio-adsorbent was 26.54 nm, and those of the remaining materials were between 5.40 and 7.33 nm. With R² = 0.998–1.000, the kinetics fit the pseudo-second-order model better, suggesting that chemisorption is the dominant mechanism. Both Langmuir and Freundlich isothermal models fit the data well, with R² = 0.946–0.999. It can be concluded that all the bio-adsorbents tested have the potential to efficiently remove lead ions from water. Full article

Adsorption is one of the simplest and most cost-effective techniques for water decontamination. In this field, biochar has recently emerged as a promising alternative to traditional adsorbents, exhibiting a high surface area and affinity to metal ions, as well as often being waste-derived. Similarly, reduced graphene oxide (rGO) shows an excellent adsorption capacity. Having self-assembling properties, it has already been employed to obtain self-standing heavy-metal-adsorbing membranes. In this research, a novel self-standing membrane of biochar and rGO is presented. It was obtained through an eco-friendly method, consisting of the simple mechanical mixing of the two components, followed by vacuum filtration and mild drying. Vine pruning biochar (VBC) was employed in different rGO/biochar mass ratios, ranging from 1/1 to 1/9. The best compromise between membrane integrity and biochar content was achieved with a 4/6 proportion. This sample was also replicated using chestnut-shell-derived biochar. The composite rGO–biochar membranes were characterized through XRD, FTIR-ATR, TG-DTG, SEM-EDX, BET, ZP, particle dimension, and EPR analyses. Then, they were tested for metal ion adsorption with 10 mM Cu²⁺ and 100 mM Zn²⁺ aqueous solutions. The adsorption capacity of copper and zinc was found to be in the range of 1.51–4.03 mmol_Cu g⁻¹ and 18.16–21.99 mmol_Zn g⁻¹, respectively, at an acidic pH, room temperature, and contact time of 10 min. Interestingly, the composite rGO–biochar membranes exhibited a capture behavior between that of pure rGO and VBC. Full article

Mead is described as a traditional alcoholic drink produced by fermentation from a solution of honey and water. It has been produced as a refreshing drink. However, in the past, it was more expensive than wine, which led to a decrease in demand. Due to the simple method of production, the mead industry is growing again. The quality and physicochemical properties of mead depend on the type of honey used. The goal of this study is to produce mead from two kinds of honey of different floral origins, chestnut and sunflower, in order to determine the differences using sensory and physicochemical analyses. The fermentation process was monitored until the extract values were consecutively the same. The results obtained in this research indicate that chestnut honey mead took a longer time to ferment, 2 months, while sunflower honey mead took 1.5 months to ferment. The alcohol content in chestnut honey mead was 7.2% v/v, and sunflower honey mead contained 8.6% v/v. Sensory-wise, the chestnut mead was more acceptable to consumers due to a more pronounced color and thus received a one-point higher score (15) than sunflower honey mead (14). Full article

Industrial residues are sources of functional biopolymers with interesting properties for textile applications. This study aims to evaluate the impact of enzymatic pre-treatment on oil yield and phenolic compounds’ content in an aqueous extraction process, as well as the functional properties incorporated into textiles. This research investigated the influence of residue granulometry, biomass percentage, and the application of enzymatic pre-treatment with different enzymes (cellulase, pectinase, xylanase) individually or in combination. Chestnut hedgehog (CH), tobacco plant stems (TPSs), vine shoot trimmings (VSTs), and beer spent grain (BSG) were explored. For textile functionalization, the extracted oils were incorporated into a bio-based formulation and applied on cotton fabric through pad-dry-cure. For CH, the pre-treatment with cellulase and xylanase achieved an oil yield of 149 and 148 mg oil/mL extract, respectively. With the combination of both enzymes, the richest oil in phenolic compounds was extracted: 1967.73 ± 16.86 mg GAE/g biomass. CH and TPS oils presented an antioxidant activity above 60%, and the functionalized textiles also showed the highest antioxidant potential and a UPF of 30. The textiles presented water repellence and washing fastness. This study demonstrates a sustainable oil extraction method and its potential application in the development of functional textiles. Full article

Chestnut is one of China’s traditional export commodities in the international market and enjoys a positive reputation. Its key quality attributes are closely linked to changes in the physicochemical properties of chestnut starch after thermal processing. This study investigated the effects of different temperatures (100 °C, 160 °C, and 200 °C) and times (10, 20, and 30 min) of dry heat treatment (DHT) on the physicochemical and structural properties, as well as the functional properties of chestnut starch. The results demonstrated that DHT increased the solubility (S) and water absorption capacity (WAC), but reduced the swelling power (SP), transmittance, and gelatinization characteristics. DHT modified the starch’s functional properties, increasing its digestibility. This was reflected in the rise in rapidly digestible starch (RDS) and the decline in resistant starch (RS) content. Scanning electron microscopy (SEM) revealed that cracks, crevices, and pores appeared on the starch granule surfaces after DHT. X-ray diffraction (XRD) analyses revealed that the relative crystallinity (RC) of starch decreased with higher temperatures and longer treatment times. The ability of DHT to alter the physicochemical and functional properties of starch provides foundational data for the possible modification of chestnut starch and its application in starch-based food products. Full article

The aim of this paper was to obtain activated biocarbons from the natural biomass of horse chestnut seeds (Aesculus hippocastanum) by physical activation with two different activating agents, carbon dioxide and water vapor, and to evaluate their structural and adsorption properties. The effect of the pyrolysis atmosphere on the surface development and porosity as well as the structure and adsorption properties of the materials in relation to the selected organic adsorbates (tetracycline (TC), naproxen (NPX), and methyl orange (MO)), which may constitute a potential contamination of the aquatic environment, was evaluated. Activated biocarbons were characterized using N₂ low-temperature adsorption/desorption, Raman and FT-IR spectroscopy, and thermogravimetric analysis (TGA). The nature of the surface (pH_pzc and Boehm titration) was also studied. Micro/mesoporous biocarbons were obtained with an S_BET area in the range of ~534 to 646 m²/g, in which micropores constituted ~70%. It was proved that the obtained materials are characterized by high adsorption values (~120 mg/g, ~150 mg/g, and ~252 mg/g) and removal rates %R (~80%, ~95%, and ~75%) for TC, NPX, and MO, respectively. The results indicate that chestnut-derived activated biocarbons are a promising, cost-effective and environmentally friendly alternative for removing organic contaminants from aqueous solutions. Future research should focus on optimizing activation parameters and assessing the long-term performance of adsorbents. Full article

Wood, a vital material for both modern and heritage objects, is particularly susceptible to degradation caused by water due to its hydrophilic nature and porous structure. Therefore, developing sustainable strategies to protect wood is of significant importance. This study aims to produce a highly hydrophobic coating for the protection of wood following a straightforward procedure and using materials that are compatible with wood. First, nano/sub-microlignin (NL) is isolated and produced from beech wood through a one-step tailored organosolv process. Next, NL is incorporated into Sivo 121, a water-borne and solvent-free silane system recommended by the manufacturer for protecting wood surfaces. Composite coatings containing various concentrations of NL and Sivo 121 are applied to chestnut (Castanea spp.) and oak (Quercus spp.). The impact of NL concentration on the contact angles of water drops (CAs) and colour changes (ΔE) of the treated wood specimens is investigated. The coating with 4% w/w NL demonstrates enhanced hydrophobicity (CA = 145°) and has a negligible effect on the colour of pristine oak (ΔE < 3). The wetting properties of coated oak are not affected after 100 tape peeling cycles. However, the coating exhibits poorer performance on chestnut, i.e., CA = 135°, which declines after 80 peeling cycles, and ΔE > 5. The drop pH does not have any noticeable effect on CA. The latter remains stable even after prolonged exposure of coated oak and chestnut samples to artificial UV radiation and outdoor environmental conditions. Finally, the composite coating offers good and comparable protection for both wood species in the biological durability soil burial test Full article

This study explores the valorization of non-commercial chestnut waste from the Portuguese chestnut industry to develop biocomposites. The composites were obtained by hot compression molding, and a Box–Behnken Design model was employed to optimize the mechanical, thermal, and water resistance properties of the chestnut-based composite, using fruit and shell fibers, respectively, as the polymeric matrix and reinforcement agent. The optimal formulation, comprising 70% chestnut, no glycerol, a molding temperature of 120 °C, and applying a pressure of 2.93 MPa for 30 min, achieved a Flexural Strength of 9.00 MPa and a Flexural Modulus of 950 MPa. To enhance water resistance, shellac was added as a natural hydrophobic coating. Water interaction tests indicated that shellac-treated biocomposites exhibited superior water resistance, absorbing approximately two times less water than those containing glycerol or untreated samples. Thermal analysis revealed that glycerol acted as a plasticizer, improving flexibility and reducing the glass transition temperature. Additionally, the chestnut-based biocomposite demonstrated an out-of-plane thermal conductivity of 0.79 W/m·K, categorizing it as a thermal insulator. The final prototype application was a candle holder, showcasing the potential for the practical and sustainable use of chestnut-based composite. This research highlights the potential for chestnut waste to be repurposed into eco-friendly products, offering an alternative to conventional plastics and contributing to a circular economy. Full article

Biochar is potentially a functional ingredient in animal nutrition that offers health benefits such as detoxification, while also promoting environmental sustainability through carbon sequestration, emission reduction, and its circular production. However, the heterogeneity of commercially available biochar products requires a detailed assessment of their functional properties for applications in animal feed. This study evaluates chestnut biochar from morphological, chemical, and metabolomic perspectives and assesses its functional properties. Metabolomic analysis of a water extract using QTOF HPLC-MS/MS confirmed the presence of bioactive compounds, such as hydroxybenzoic and succinic acids, highlighting its potential as a functional feed ingredient. The chestnut biochar inhibited the growth of the pathogenic E. coli strains F18+ and F4+, with maximum inhibition rates of 15.8% and 28.6%, respectively, after three hours of incubation. The downregulation of genes associated with quorum sensing (MotA, FliA, FtsE, and HflX, involved in biofilm formation and cellular division) suggests that biochar interferes with several aspects of the pathogenic process. Importantly, biochar was not found to adversely affect beneficial probiotic bacteria, such as Lactiplantibacillus plantarum and Limosilactobacillus reuteri. These findings support the potential of chestnut biochar as a versatile ingredient for sustainable animal nutrition, thus promoting animal welfare while offering environmental benefits. Full article

Fungi can be used as bioindicators to assess the biodiversity and conservation status of different habitats because of their high adaptability and sensitivity to changes in water, air, and soil quality. In this study, records of macrofungi and lichenised fungi were extracted from GBIF, surveyed using GIS software, and used to compare the fungal diversity of the Pyrenean oak and chestnut groves of Castilla y León, analysing the possible implications of their presence for the conservation of these forest habitats. In Quercus pyrenaica forests, a greater number of lichen and macrofungi species and records were recorded than in Castanea sativa forests, although the greater area occupied by the former could have influenced this diversity. The higher presence of ectomycorrhizal macrofungal species in chestnut groves, as well as the higher sensitivity to pollution of lichens in Pyrenean oak-dominated environments, showed the relevance of the analysis of these data for a better understanding of the conservation status of forest habitats. However, in order to obtain more accurate results, it would be necessary to carry out specific studies on a smaller scale. Full article