Search Results (43)

Water-reducing admixtures are of enormous importance to adjust the workability of alkali-activated materials. Especially in geopolymers activated by highly concentrated alkaline solutions, the polycarboxylate ether (PCE) superplasticizers are less effective than in conventional cementitious systems. The aim of this study was to clarify the reasons for the lower dispersing performance of PCE and the synthesis of alternative dispersing agents based on the biopolymer starch to improve the workability of highly alkaline geopolymers. Furthermore, the focus of investigations was on the role of activator type and concentration as key parameters for geopolymer reaction and interaction of water-reducing agents. Therefore, in this study the conformation of three different types of PCE (MPEG: methacrylate ester, IPEG: isoprenol ether, and HPEG: methallyl ether) and synthesized starch admixtures in sodium and potassium hydroxide solutions (1 mol/L up to 8 mol/L) were studied. Furthermore, the dispersing performance, adsorption behavior, and influence on reaction kinetics in metakaolin-based geopolymer pastes were investigated in dependence on activator type and concentration. While the PCE superplasticizers show coiling and formation of insoluble aggregates at activator concentrations of 3 mol/L and 4 mol/L, the synthesized starch admixtures show no significant change in conformation. The cationic starch admixtures showed a higher dispersing performance in geopolymer pastes at all activator concentrations and types. The obtained adsorption isotherms depend strongly on the activator type and the charge density of the starch admixtures. The reaction kinetics of geopolymer pastes were not significantly influenced using the synthesized starch admixtures. Especially the cationic starch admixtures allow the reduction of liquid/solid ratios, which leads to higher flexural and compressive strengths. Full article

Cooked-rice aroma strongly affects consumer choice, yet the chemical traits distinguishing glutinous rice from normal-amylose japonica rice remain underexplored because earlier studies targeted only a few dozen volatiles using one-dimensional gas chromatography–mass spectrometry (GC-MS). In this study, four glutinous and seven normal Japanese cultivars were cooked under identical conditions, their headspace volatiles trapped with MonoTrap and qualitatively profiled by comprehensive GC × GC-TOFMS. The two-dimensional platform resolved 1924 peaks—about ten-fold previous coverage—and, together with hierarchical clustering, PCA, heatmap visualization and volcano plots, cleanly separated the starch classes (78.3% cumulative PCA variance; Euclidean distance > 140). Volcano plots highlighted 277 compounds enriched in the glutinous cultivars and 295 in Koshihikari, including 270 compounds that were not previously documented in rice. Normal cultivars were dominated by ethers, aldehydes, amines and other nitrogenous volatiles associated with grainy, grassy and toasty notes. Glutinous cultivars showed abundant ketones, furans, carboxylic acids, thiols, steroids, nitro compounds, pyrroles and diverse hydrocarbons and aromatics, yielding sweeter, fruitier and floral accents. These results expand the volatile library for japonica rice, provide molecular markers for flavor-oriented breeding and demonstrate the power of GC × GC-TOFMS coupled with chemometrics for grain aroma research. Full article

In this study, a novel starch-based adhesive (SBA) was proposed, which mainly involved the synthesis of a carboxyl-terminated hyperbranched polymer using bisphenol A diglycidyl ether (DGEBA) and citric acid as raw materials. Subsequently, starch was modified through hyperbranching to enhance the shear strength and water resistance of the SBA. For this purpose, the feasibility of the reaction between DGEBA and citric acid was analyzed using quantum mechanical simulations. Subsequently, both substances were simulated to synthesize carboxyl-terminated hyperbranched polymers with different ratios. Starch was modified through hyperbranching to establish various models of SBAs, and their properties were estimated using molecular dynamics simulations. Theoretical analysis indicates that a DGEBA-to-citric acid ratio of 3:7 yields a SBA with relatively optimal properties. The solubility parameter of this adhesive is 19.05 (J/cm³)¹/², suggesting strong intermolecular interactions between the hyperbranched polymer and starch. The synthesized adhesive exhibits high cohesive strength, with an estimated water contact angle of up to 138°, indicating good hydrophobicity. Furthermore, the system demonstrates favorable mechanical performance, with a shear modulus of 4.34 GPa and a bulk modulus of 8.80 GPa. Additionally, at this ratio, the SBA exhibits a relatively high interaction energy of −408.01 kcal/mol with the cellulose substrate, suggesting that the adhesive possesses favorable shear strength. Full article

With the concept of sustainable development gaining increasing traction, the high-value utilization of forest biomass has received growing attention. In this study, an acorn-based wood adhesive was developed using Quercus fagaceae, offering a sustainable alternative that not only supports the multifunctional use of acorn shell resources, but also reduces dependence on fossil-based materials in traditional wood adhesives, a development of significant importance to the wood industry. The effects of various crosslinking agents and phenolic resin (PF) additions on the performance of the acorn-based adhesive (AS) were investigated. Among the crosslinking agents tested, isocyanate (MDI), epoxy resin E51, and trimethylolpropane diglycidyl ether (TTE), PF demonstrated the best bonding performance. The modified AS adhesive with a 30% PF addition showed the highest bonding strength (0.93 MPa) and superior water resistance. These improvements are attributed to the formation of a stable, multi-dimensional crosslinked network structure resulting from the interaction between gelatinized starch molecules and PF resin. Moreover, the AS-PF adhesive exhibited a remarkably low formaldehyde emission of 0.14 mg/L, representing a 90.67% reduction compared to the national E1 standard. The incorporation of PF also enhanced the adhesive’s mildew resistance and toughness. These findings highlight the potential of acorn-based adhesives as a sustainable alternative for applications in the wood and bamboo industries. Full article

Background: Sugarcane is an important sugar crop. Sugarcane stems are mainly used for sugar extraction, while leaves can only be burned as waste. However, sugarcane leaves can also produce a large number of secondary metabolites, and these metabolites have significant nutritional and pharmacological value. At present, there are few studies on sugarcane compounds. Methods: Therefore, the stems and leaves of three sugarcane varieties (Yacheng 89-159, Dianzhe 01-58, ROC22) were selected as experimental materials, and the compounds of stems and leaves of different sugarcane were studied using high-performance liquid chromatography. Results: Metabolomics analysis detected 1197 metabolites that could be broadly divided into 11 categories. Orthogonal partial least squares discriminant analysis identified metabolites that were differentially abundant across groups (stems and leaves within and across the three varieties). Flavonoids, phenolic acids, and lipids were the main differential metabolites. Notably, tricin-4′-O-(guaiacylglycerol)ether-7-O-glucoside, quercetin-3,4-O-di-glucoside, cyanidin-3-O-(6′′-O-malony)glucoside were significantly higher in the stems than in the leaves across all three varieties. The content of methylenesuccinic acid was higher in the leaves of Dianzhe 01-58 and ROC22. In the comparative analysis of the top 20 differential metabolites among different varieties, it was found that the metabolite content of stems and leaves of Yacheng 89-9 and ROC22 was significantly higher than that of Dianzhe 01-58. Next, KEGG analysis showed that these differential metabolites were mainly enriched in pathways related to flavonoid, phenylpropanoid, and isoflavonoid biosynthesis, as well as starch and sucrose metabolism. Leaves also had significantly fewer metabolites involved in starch and sucrose metabolism than stems did. Conclusion: In conclusion, this study provides a scientific basis for utilization of sugarcane compounds, laying a theoretical foundation for further processing of sugarcane by-products into higher-value materials. Full article

Probiotics improve the quality of silage during the planting and fermentation processes. This study was designed to investigate the accumulation of nutritional components in the fresh corn variety Jingkenuo 2000 waxy maize under different fertilization conditions and its effectiveness as silage feed. The nutrient accumulation trends of dry matter (DM), starch, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), and ether extract (EE) in the stems, leaves, grains, and whole plant of Jingkenuo 2000 waxy maize were evaluated during different growth cycles. The relative feed value (RFV) was also assessed, with the results showing that the whole plant of Jingkenuo 2000 waxy maize at the wax stage was most suitable for use as silage. The experiment conducted in the present study was carried out in a completely random block design with two additives and three fertilizer application conditions: no-additive + conventional fertilization treatment (CKCK); no-additive + conventional fertilization + drip irrigation of bacterial solution treatment (CKJJ); no-additive + conventional fertilization + microbial organic fertilizer treatment (CKYJ); additive + conventional fertilization treatment (FJCK); additive + conventional fertilization + drip irrigation of bacterial solution treatment (FJJJ); and additive + conventional fertilization + microbial organic fertilizer treatment (YJFJ). Additionally, the nutrient composition, fermentation quality, and bacterial community structure of the silage fermentation treatments were analyzed. The results indicate that there was significant interaction between the additive and fertilization treatments, with them significantly influencing the parameters CP, EE, NDF, ADF, and RFV (p < 0.01). In particular, the treatment combining additives, conventional fertilization, and drip irrigation of bacterial solution exhibited the highest CP, EE, and starch (p < 0.01) among all the tested treatments, while also displaying the lowest NDF and ADF contents (p < 0.01). Furthermore, this treatment reduced the pH value (p < 0.01), decreased bacterial diversity, and fostered the growth of Lactobacillus. Overall, the findings presented herein demonstrate that, through precise nutritional accumulation monitoring and scientific biological pretreatment methods, Jingkenuo 2000 waxy maize has the potential to become a high-quality silage feed. Full article

Near-infrared spectroscopy (NIRS) is an efficient, non-destructive method for evaluating the chemical composition of various compounds. This study aimed to assess both the proximate composition, fibres, and fatty acid (FA) content of Total Mixed Rations (TMRs) in dairy buffalo nutrition. A total of 240 TMR samples were collected from ten dairy buffalo farms across four seasons to develop predictive models using Partial Least Squares Regression (PLSR). Calibration models for dry matter (DM), crude protein (CP), ether extract (EE), and starch demonstrated good predictive accuracy, with coefficients of determination in cross-validation (R²cv) around 0.90 and Residual Predictive Deviation (RPDcv) values exceeding 3.0. Fatty acid models showed slightly lower R²cv values, ranging from 0.80 to 0.90. A good predictive performance was observed for linoleic acid (18:2 n-6) and α-linolenic acid (18:3 n-3), with RPDp values above 3.0, indicating reliable predictions. The inclusion of omega-3-rich compounds in the diet provides significant benefits for both animal health and product quality, highlighting the importance of ration monitoring. The findings confirm that while NIRS is effective for assessing chemical composition, further refinement is needed to improve FA prediction accuracy. These results support the use of NIRS as a practical tool for nutritional monitoring in lactating buffaloes. Full article

Monensin and essential oils have antimicrobial properties that may impact silage fermentation. The present study was divided into two trials to evaluate the effects of monensin (MON) and essential limonene oils (ELO) as additives in the ensiling of total mixed ration (TMR). In the first assay, TMR was tested with sheep in growth (65% dry matter—DM) using the following treatments: control (no additive), MON35 (35 mg of monensina per kg of DM), MON45 (45 mg of monensina per kg of DM), ELO300 (300 mg of essential limonene oil per kg of DM), and ELO600 (600 mg of essential limonene oil per kg of DM). In the second assay, the same treatments were used in TMR for lactating cows under two moisture conditions (30% and 40% DM). The parameters assessed included fermentative losses, short-chain fatty acid profiles, aerobic stability (hours needed for silage to reach 2 °C above ambient), chemical composition, and in vitro DM digestibility of the silages. Treatment averages were compared using the Scott–Knott test at 5% significance. In the first assay, the treatments with ELO had the lowest (p < 0.05) pH values and the highest (p < 0.05) lactic acid concentrations, with treatment ELO600 leading to the highest (p < 0.05) aerobic stability (297.88 h). Only the starch contents of the ELO treatments were lower (p < 0.05) than the others. In the second assay, the silages with the highest moisture contents and ELO600 exhibited the lowest (p < 0.05) values of DM recovery, lactic acid, and pH. The highest (p < 0.05) lactic acid:acetic acid ratios were observed in the silages with the most moisture added with MON35 and MON45. The use of MON and ELO increased aerobic stability, with the highest (p < 0.05) values observed for ELO600 and MON35. The treatments with MON and ELO resulted in silages with the lowest (p < 0.05) fiber contents and highest ether extract and starch contents when compared with control. Thus, MON and essential oils improve fermentative quality but ELO should be used in lower doses in humid silages to avoid negative fermentation impacts. Full article

Carboxymethylglucans (CMGs) are widely used semisynthetic polyelectrolytes, e.g., for pharmaceuticals. They are produced in heterogeneous processes on activated starch granules or cellulose fibers. In contrast to neutral ether derivatives, a lower DS in the range, commonly between 0.6 and 1.2, is sufficient to achieve the water solubility of CM cellulose. The high proportion of unsubstituted domains, which could aggregate and therefore only swell and form gel particles but do not dissolve, places higher demands on the statistical distribution of the substituents. The knowledge of regioselectivity, essential for the interpretation of higher structural-level data, can be obtained by various methods, preferentially by CE/UV after hydrolysis. To study the distribution of substituents at the polymer level by mass spectrometric (MS) analysis, partial random depolymerization is required. Due to the ionic character and acid functionality, all the attempts of the direct depolymerization of CMG and further sample preparation suffered from bias, side reactions, and multiple ion formation in MS. Finally, the transformation of CMGs to the corresponding hydroxyethylglucans (HEGs) by the reduction of the esterified carboxy groups with LiAlH₄ opened the window for quantitative oligomer MS analysis. While the CM amyloses were reduced quantitatively, the transformation of the CMC was only about 60% but without the formation of mixed CM/HE ethers. Full article

This study investigated the effect of gaseous ozone (O₃) on the chemical and microbiological properties of whole-plant corn silage. Conducted on a commercial dairy farm in Brazil, maize was ensiled in experimental bag silos and treated with varying levels of O₃ (0%, 1.25%, 3.12%, 4.15%, and 6.25%). The findings revealed minimal nutrient losses in starch, non-fiber carbohydrates, crude protein, and total digestible nutrients compared to untreated fresh maize. O₃-treated silages exhibited increased levels of ash, ether extract, calcium, and phosphorus. Notably, the application of 3.12% to 4.15% O₃ improved microbiological characteristics, significantly reducing mold and yeast populations, which are common issues in farm-produced silage. This study demonstrated that gaseous ozone is a promising additive for enhancing the microbiological quality of corn silage, offering an effective alternative to traditional chemical preservatives. Full article

Corn silage is widely used in livestock farming; however, its quality is easily altered, and one of the factors that has a high influence in this regard is the region of production. The objective was to evaluate the chemical–bromatological composition of 498 samples of corn silage from mesoregions in Southern Brazil during the 2022/2023 summer harvest. The following were studied in relation to our objective: nutritional composition, dry matter, mineral matter, ether extract, starch, crude protein, neutral detergent fiber, acid detergent fiber, acid detergent lignin, total digestible nutrients, total carbohydrates, and fractions of carbohydrates. The silages from Central South-PR had higher levels of starch and ether extract (30.68% ± 6.24% and 3.41% ± 0.92%, respectively), whereas in West-SC, the silages had higher levels in the A + B1 fraction of carbohydrates (49.59% ± 6.34%). Silages in North-PR had higher concentrations of neutral detergent fiber and acid detergent fiber (49.86% ± 5.92% and 29.70% ± 4.38%, respectively), while in Northwest-RS and West-PR, silages had higher levels of the B2 carbohydrate fractions (46.25% ± 1.98% and 44.55% ± 3.84%, respectively). The nutritional composition differences presented were due to the variables of each mesoregion, interfering in the scenario of formulating diets and animal nutrition. Full article

In the last decade, a growing demand for sustainable cosmetic ingredients has yielded numerous biodegradation protocols. While OECD (Organization for Economic Co-operation and Development) aquatic assays are suitable for water-borne chemicals, it is crucial for the personal care industry to consider the persistence of plastics in soil, compost, and municipal sludge. Adopting this cradle-to-grave holistic approach would strengthen product appeal while increasing the accuracy and ethical integrity of green product labeling. The aim of our study was to employ quantitative CO₂ detection and thermophilic composting protocols specified in ASTM D5338, along with pass level criteria outlined in ASTM D6400, to assess the mineralization of plastics commonly formulated into personal care products. Our results indicate that many cellulose ethers, cationic guars, starches, proteins, and labile polyesters demonstrate satisfactory disintegration, biodegradation, and seed germination rates to secure an ASTM D6400 compostability claim. By contrast, macromolecules designed with carbon–carbon backbones resisted acceptable mineralization in composting experiments, advocating that unadulterated municipal compost lacks the microbial diversity to enzymatically digest many synthetically derived resins. Additionally, polymers that demonstrated acceptable biodegradability in internal and published OECD aquatic studies, including chitosan and polyvinyl alcohol, exhibited limited respiration in local municipal compost; hence, untested correlations between aquatic, soil, and compost testing outcomes should never be assumed. Full article

Biopolymers are biodegradable and renewable and can significantly reduce environmental impacts. For this reason, biocomposites based on a plasticized starch and cross-linker matrix and with a microfibrillated OCC cardboard cellulose reinforcement were developed. Biocomposites were prepared by suspension casting with varied amounts of microfibrillated cellulose: 0, 4, 8, and 12 wt%. Polyethylene glycol diglycidyl ether (PEGDE) was used as a cross-linking, water-soluble, and non-toxic agent. Microfibrillated cellulose (MFC) from OCC cardboard showed appropriate properties and potential for good performance as a reinforcement. In general, microfiber incorporation and matrix cross-linking increased crystallization, reduced water adsorption, and improved the physical and tensile properties of the plasticized starch. Biocomposites cross-linked with PEGDE and reinforced with 12 wt% MFC showed the best properties. The chemical and structural changes induced by the cross-linking of starch chains and MFC reinforcement were confirmed by FTIR, NMR, and XRD. Biodegradation higher than 80% was achieved for most biocomposites in 15 days of laboratory compost. Full article

The interaction of microencapsulated phase change materials (PCMs) with polymeric chemical additives in an air lime binding matrix was studied. These polymer-based additives included an adhesion booster (derived from starch) and a superplasticizer (polycarboxylate ether). Two different PCMs with melting points of 18 °C and 24 °C were assayed. The microcapsules were composed of melamine, with paraffin-based PCM cores. Measurements of zeta potential, particle size distribution, adsorption isotherms, and viscosity analyses were performed to comprehend the behavior of the polymer-based additives within the air lime matrix and their compatibility with PCMs. Zeta potential experiments pointed to the absence of a strong interaction between the lime particles and the microcapsules of PCMs. At the alkaline pH of the lime mortar, the negative charge resulting from the deprotonation of the melamine shell of the microcapsules was shielded by cations, yielding high positive zeta potential values and stable dispersions of lime with PCMs. The polycarboxylate ether demonstrated the ability to counteract the increase in mixing water demand caused by the PCM addition in the lime matrix. The dispersing action of the superplasticizer on the lime particles was seen to exert a collateral dispersion of the PCMs. Conversely, despite the positive values of zeta potential, the addition of the starch-based additive resulted in the formation of large PCM-lime clumps. Air lime renders incorporating 5, 10, and 20% PCMs by weight with various dosages of these chemical additives were experimented with until the optimal formulation for the specific application of the mortars as renderings was achieved. This fine-tuned formulation effectively tackled issues commonly associated with the addition of PCMs to mortars, such as poor adhesion, crack formation, and reduced fluidity. Full article

We used published data consisting of 263 treatment mean observations from beef cattle and dairy steers and heifers, in which CH₄ was measured via chambers or head boxes, to evaluate relationships between enteric CH₄ production and dry matter intake (DMI) and dietary components. Daily DMI was positively related (slope = 15.371, p < 0.001) to total daily production (g/d) of CH₄ (r² = 0.821). Among chemical components, dietary neutral detergent fiber (NDF) concentration was the most highly related (r² = 0.696; slope = 0.2001; p < 0.001) to CH₄ yield (g/kg of DMI), with strong relationships also noted for dietary starch:NDF ratio (r² = 0.662; slope = −2.4587; p < 0.001), starch (r² = 0.495; slope = −0.106; p < 0.001), and the proportion of metabolizable energy relative to gross energy (r² = 0.561; slope = −23.663; p < 0.001). The slope (−0.5871) and intercept (22.2295) for the dietary ether extract vs. CH₄ yield were significant (p < 0.001), but the relationship was highly variable (r² = 0.150). For dietary crude protein concentration, the slope for CH₄ yield was not significant (−0.0344; p < 0.381) with an r² value near zero. Decreasing DMI by programming body weight gain or restricting feed intake could decrease CH₄ production in confined cattle, but these approaches might negatively affect growth performance and product quality, potentially negating positive effects on CH₄ production. Feeding higher-quality forages or using grazing management systems that decrease dietary NDF concentrations or substituting grain (starch) for forage should decrease both CH₄ yield from enteric production and manure CH₄ production via increased digestibility. Effects of feeding management and diet formulation strategies should be additive with other mitigation approaches such as feed additives, allowing the cattle industry to achieve maximal decreases in enteric CH₄ production, while concurrently maintaining optimal beef production. Full article