Search Results (103)

This study aimed to investigate the effects of baicalin and citric acid on egg production performance, egg quality, and the intestinal morphology and function of laying hens. A total of 600 Hy-Line Brown laying hens, 59 weeks old, were randomly allocated to four dietary treatments, with 10 replicates per treatment and 15 hens per replicate. The control group was fed a basal diet, while the other three groups were fed the basal diet supplemented with 150 mg/kg baicalin (B), 2000 mg/kg citric acid (CA), or 150 mg/kg baicalin plus 2000 mg/kg citric acid (B + CA), respectively. The experimental period lasted for 12 weeks, and the results indicated that neither the individual addition nor the combined application of baicalin and citric acid had a significant impact on the laying performance. However, compared with the control group, the baicalin and/or citric acid supplementation significantly increased the eggshell strength and Haugh unit. Additionally, the combination of baicalin and citric acid significantly increased the villus height and the villus height/crypt depth ratio in the duodenum and jejunum. It also enhanced the population of beneficial bacteria, such as Lactobacillus and Bifidobacterium, in the cecum and improved the activity of intestinal digestive enzymes, primarily disaccharidases. Furthermore, the addition of baicalin to the diet significantly increased the content of Secretory Immunoglobulin A in the ileum and jejunum after 12 weeks of feeding. These results suggest that the combination of baicalin and citric acid had a synergistic effect on the improvement of egg quality and intestinal morphology and function in laying hens. Overall, our findings provide important insights into the potential benefits of supplementing baicalin and citric acid in the diet of laying hens and may have practical implications for improving egg quality and poultry health status. Full article

Chromium slag sites pose severe environmental risks due to hexavalent chromium (Cr(VI)) contamination, characterized by high mobility and toxicity. This study focused on chromium-contaminated soil from a historical chromium slag site in North China, where long-term accumulation of chromate production residues has led to serious Cr(VI) pollution, with Cr(VI) accounting for 13–22% of total chromium and far exceeding national soil risk control standards. To elucidate Cr(VI) transformation mechanisms and elemental linkages, a combined approach of macro-scale condition experiments and micro-scale analysis was employed. Results showed that acidic conditions (pH < 7) significantly enhanced Cr(VI) reduction efficiency by promoting the conversion of CrO₄²⁻ to HCrO₄⁻/Cr₂O₇²⁻. Among reducing agents, FeSO₄ exhibited the strongest effect (reduction efficiency >30%), followed by citric acid and fulvic acid. Temperature variations (−20 °C to 30 °C) had minimal impact on Cr(VI) transformation in the 45-day experiment, while soil moisture (20–25%) indirectly facilitated Cr(VI) reduction by enhancing the reduction of agent diffusion and microbial activity, though its effect was weaker than chemical interventions. Soil grain-size composition influenced Cr(VI) distribution unevenly: larger particles (>0.2 mm) in BC-35 and BC-36-4 acted as main Cr(VI) reservoirs due to accumulated Fe-Mn oxides, whereas BC-36-3 showed increased Cr(VI) in smaller particles (<0.074 mm). μ-XRF and correlation analysis revealed strong positive correlations between Cr and Ca, Fe, Mn, Ni (Pearson coefficient > 0.7, p < 0.01), attributed to adsorption–reduction coupling on iron-manganese oxide surfaces. In contrast, Cr showed weak correlations with Mg, Al, Si, and K. This study clarifies the complex factors governing Cr(VI) behavior in chromium slag soils, providing a scientific basis for remediation strategies such as pH adjustment (4–6) combined with FeSO₄ addition to enhance Cr(VI) reduction efficiency. Full article

Phytosterols (PS) have specific oxidation rules in different lipid media. After oxidation, PS will form oxidation products, which has potential physiological toxicity to the human body. Camellia seed oil (CSO) is a unique emerging edible oil in China. This oil has a fatty acid composition similar to olive oil, in which oleic acid is dominant. In order to solve the thermal oxidation of PS in CSO at high temperature (180 °C), we studied its antioxidant strategy by evaluating different antioxidants. Four antioxidants—BHA, TBHQ, epigallocatechin gallate (EGCG), and α-tocopherol (VE)—along with one synergist, citric acid (CA), were selected and used in this study. The antioxidant effects of different combinations (single antioxidant, single antioxidant + CA, mixed antioxidant, mixed antioxidant + CA) were compared. After 180 min of heating, the PS and phytosterols oxidation products (7α-hydroxy-, 7β-hydroxy-, 5α,6α-epoxy-, 5β,6β-epoxy-, 7-keto-, and trihydroxy-PS) were estimated by GC-MS. Through comparative analysis, the results showed that the combination of mixed antioxidants and CA had the best antioxidant effect, and the inhibition rate of VE + TBHQ +CA was as high as 42%, which had a breakthrough significance for stabilizing the thermal oxidation of PS in camellia seed oil. At the same time, it also provides a valuable reference for ensuring the edible safety of camellia seed oil in Chinese food heating habits. Full article

Lulo or naranjilla (Solanum quitoense Lam.) is an Andean fruit with a sour and refreshing flavor, widely used in the preparation of juices and sweets. Despite its potential for international markets, it remains largely unknown outside its native regions, and most existing studies have focused on the whole fruit or its juice. This study investigated the nutritional and phenolic profiles of the peel, pulp, and seeds of S. quitoense using official food analysis methods and chromatographic techniques. In addition, the in vitro antioxidant activity and antimicrobial effects against foodborne fungi and bacteria were assessed. The peel was rich in ascorbic acid (25.2 mg/100 g fw), α-tocopherol (7.9 mg/100 g fw), dietary fiber (16.5 g/100 g fw), macrominerals (Na, Ca, K), and flavonoids (14.2 mg/g extract); the pulp contained high levels of citric acid (4.22 g/100 g fw) and sucrose (2.7 g/100 g fw); and the seeds stood out for their contents of trace elements (Zn, Cu, Mn, Fe), oleic acid, and spermidine-derived phenolamides (37.8 mg/g extract). Hydroethanolic extracts showed antioxidant activity by inhibiting lipid peroxidation and oxidative hemolysis, with the seed extract exhibiting the strongest antifungal effect against Aspergillus versicolor, likely due to its high spermidine derivative content. These findings shed light on the potential of S. quitoense fruit for the development of functional foods, antioxidant-rich beverages, and nutraceutical products. Full article

The chemical composition of Aloe vera leaves was investigated by using liquid chromatography–high-resolution tandem mass spectrometry (LC-HRMS/MS). Five A. vera samples were collected across diverse geographical origins and cultivation practices: PO (Botanical Garden of Portici, Italy), CAN (Gran Canaria, Canary Islands), CA, E, and MM (Marine Reserve of Torre Guaceto, Brindisi, Italy). Analysis of hydroalcoholic organic extracts revealed 77 organic compounds, including ubiquitous primary metabolites (i.e., sugars, amino acids, and fatty acids) and natural products (i.e., phenols and aromatics, terpenes, and anthraquinones). Principal component analysis (PCA) on the raw dataset indicated a clear separation of samples depending on their geographical origins. PO samples showed high amounts of citric acid, the anthraquinone aloe-emodin, and the alkaloids tropine and tropinone. CAN samples showed high content of malic, citramalic, citraconic, erucic, and 3-dehydroquinic acids. CAN and PO samples contained high amounts of jasmonic, quinic, and 4-methoxycinnamic acids along with aloesin, tyramine, coumarin, and saponarin. Among the Brindisi samples, MM contained high amounts of limonene and α-linolenic acid. CA, E, and MM samples presented high amounts of eritrose-4-phosphate, glucose-1-phosphate, and fructosyl valine along with ginsenoside, proline, and ascorbic acid. These findings indicate that geographical origins and cultivation practices affect to different extents the metabolite profile of A. vera plants. Full article

The use of chemical stimulants in resin tapping is essential for prolonging the resin flow and enhancing production. Traditional stimulants, primarily composed of sulfuric acid, pose concerns related to workplace safety, environmental impact, and tree health. In this study, we compared alternative stimulant pastes containing ethrel, salicylic acid, and citric acid with the traditional Spanish and Brazilian stimulant pastes with higher contents of sulfuric acid. We tapped Pinus pinaster seedlings with five different stimulants, using untreated and mechanically wounded plants as controls. The resin yield, tree growth, and physiological parameters were compared. The pines stimulated with citric acid released ca. 50% more resin, while ethrel and salicylic acid yielded similar amounts to the traditional paste, suggesting their potential as viable alternatives. Although all stimulants reduced the seedling growth, no significant differences were observed in the midday water potential or stomatal conductance. The internal resin accumulation and resin canal density were strongly correlated with the total resin production, and more-acidic pastes tended to cause xylem damage and resin retention. Our findings suggest that moderate acidity is sufficient to trigger resin biosynthesis and release, and that safer, less corrosive formulations, like citric acid, may provide viable, safer, and more sustainable alternatives to conventional stimulants. While the results from the seedlings provide a rapid and cost-effective screening tool, anatomical and physiological differences from mature trees should be considered when extrapolating findings to operational settings. Full article

The textile industry is under increasing pressure to adopt sustainable practices due to the significant environmental impacts associated with fiber production, including high energy consumption, water usage, and substantial greenhouse gas emissions. The recycling of textile waste, particularly cotton, is a promising solution that has the potential to reduce landfill waste and decrease the demand for virgin fibers. However, mechanically recycled cotton fibers frequently demonstrate diminished mechanical properties compared to virgin fibers, which limits their potential for high-quality textile applications. This study explores the use of cross-linking agents (citric acid (CA) and sodium hypophosphite (SHP)), polymers (polyethylene glycol (PEG), chitosan (CH), carboxymethyl cellulose (CMC) and starch (ST)), and silicas (anionic (SA) and cationic (SC)) to enhance the mechanical properties of recycled cotton fibers. The treatments were then subjected to a hierarchical ranking, with the effectiveness of each treatment determined by its impact on enhancing fiber tenacity. The findings of this research indicate that the most effective treatment was starck (ST_50), which resulted in an enhancement of tenacity from 14.63 cN/tex to 15.34 cN/tex (+4.9%), closely followed by CA-SHP_110/110, which also reached 15.34 cN/tex (+4.6%). Other notable improvements were observed with CMC_50 (15.23 cN/tex), PEG_50 (14.91 cN/tex), and CA_50 (14.89 cN/tex), all in comparison to the control. In terms of yarn quality, the CA-SHP_110/110 treatment yielded the most substantial reductions in yarn irregularities, including thin places, thick places, and neps with decreases of 36%, 10%, and 7%, respectively. Furthermore, CA_50 exhibited moderate enhancements in yarn regularity, thin places (−12%), thick places (−6.1%), and neps (−8.9%). The results of this study demonstrate that combining CA with SHP, particularly when preceded by the heating of the solution before the addition of the fibers, results in a substantial enhancement of the structural integrity, strength, and overall quality of recycled cotton fibers. This approach offers a viable pathway for the improvement of the performance of recycled cotton, thereby facilitating its wider utilization in high-quality textile products. Full article

The growth of plants highly depends on the soil’s water availability and properties. Hydrogels (HGs) have been used for decades to enhance soil water retention, whereas developing eco-friendly and sustainable HGs for agricultural applications is still necessary to ensure water and food security. In this study, renewable and cost-effective HGs were prepared from all-lignocellulose fibers of date palm biomass after carboxymethylation followed by citric acid (CA) crosslinking. HGs showed high equilibrium swelling capacity (EWC%), even in salty media, whereas purified HGs showed about 700–400 EWC% in deionized water. Further, HGs’ effect on germination was studied on Chico III tomato, mint, Basilico red, and chia seeds. The results revealed that HGs enhanced the soil properties, with taller and healthier plants observed in HG-amended soil. FTIR, thermal analysis, and microscope imaging were utilized to evaluate HGs’ and raw materials’ characteristics. The findings in this study support the idea that all-lignocellulose could be used for HG production without separation. Full article

Chlorine dioxide (ClO₂) is a powerful sterilizing agent that is widely used to prevent the spoilage of fresh foods during delivery and storage. However, its practical applications are hindered by a short sterilization duration, complex deployment processes, and high treatment costs. To address these challenges, an innovative ClO₂ self-releasing sachet was developed, which was specifically designed for use in retail and wholesale markets. The sachet utilizes polyether block amide (PEBAX^®) as a hydrophilic polymer to facilitate the dissociation of sodium chlorite (NaClO₂) and citric acid (CA), which generates ClO₂. A PEBAX/CA composite film was coated onto kraft paper to construct the sachet. This design extended the ClO₂ release period to over 3 d, with a controllable release rate being achieved by adjusting the concentrations of NaClO₂ and CA. In practical tests, the sachets inhibited fungal growth by >50% over 14 d at 20 °C within a corrugated box. Furthermore, they preserved the quality of the cherry tomatoes for 16 d during storage. These results demonstrate that the newly developed sachet offers an economical and user-friendly solution for fresh-food packaging, effectively preserving product quality. Full article

Aragonite calcium carbonate (CaCO₃), derived from cockle shell waste, was successfully used as a renewable calcium source to synthesize calcium citrate (CCT) using citric acid (C₆H₈O₇). The three CCT products (CCT-2, CCT-3, and CCT-4) were prepared using three different acid concentrations: 2, 3, and 4 M. The physicochemical characteristics of the newly synthesized CCT were investigated. Fourier-transform infrared (FTIR) spectra revealed the vibrational modes of the citrate anionic group (C₆H₅O₇³⁻), which preliminarily confirmed the characteristics of CCT. However, X-ray diffraction (XRD) revealed that the concentration of citric acid altered the structural property and the chemical formula of the synthesized CCT. Employing 2 M citric acid, a pure tetra-hydrated phase (Ca₃(C₆H₅O₇)₂·4H₂O, earlandite mineral) was obtained. However, a mixture of hydrated (Ca₃(C₆H₅O₇)₂·4H₂O) and anhydrous (Ca₃(C₆H₅O₇)₂) phases was precipitated when 3 and 4 M citric acid was used in the preparation process. The lower mass loss observed in the thermogravimetric analysis (TGA) of CCT-3 and CCT-4 compared to that of CCT-2 further confirmed that CCT-3 and CCT-4 were composed of hydrated and anhydrous CCTs. The synthesized CCT decomposed in four major processes: the first dehydration, the second dehydration, CaCO₃ formation, and decarbonization, generating calcium oxide (CaO) as the final product. X-ray fluorescence (XRF) results showed that the CCT mainly consisted of CaO with a quantity of >98%. The scanning electron microscopic (SEM) image revealed the irregular plate-like CCT crystallites. The concentration of citric acid is a key factor that influences the productive parameters of CCT, including production yield, reaction time, and solubility. 2 M citric acid provided the optimal balance between productivity and cost-effectiveness, with the highest yield and soluble fraction and the lowest reaction time. The results suggest that the preparation of CCT from cockle shell waste can potentially replace the use of commercial calcite from mining, which is a limited and non-renewable resource. Full article

Argan oil is known worldwide for its nutritional, therapeutic, and cosmetic benefits. However, the extraction process produces 40–50% of argan press cake (APC), which is rich in protein, fiber, and minerals. Despite its nutritional potential, the high saponin content of APC imparts a bitter taste and anti-nutritional properties, making it unsuitable for human consumption and often wasted. This study addresses this issue by using boiling treatments with citric acid (CA) and distilled water (DW) to reduce the saponin content while evaluating the impact on APC quality. In addition, this study explores, for the first time, the incorporation of treated argan press cake, APC-CA and APC-DW, at different levels (5%, 10%, 15%, and 20%) into whole wheat flour (WWF) for bread production to improve the nutritional profile. The results indicate that both treatments significantly reduce saponin content while maintaining nutritional quality comparable to untreated APC. This includes a 50% reduction in phytic acid levels. The absence of tryptophan fluorescence emission was observed in APC-CA, which may be related to chemical degradation or interactions with other molecules. The substitution of APC-CA and APC-DW increased the protein of composite flours in a level-dependent manner. At substitution levels up to 10%, APC-CA and APC-DW positively influenced the technological properties of the bread. This study demonstrates the potential of APC to improve the nutritional value of bread and supports zero-waste initiatives by reusing by-products. Full article

Carbon dots (CDs) have attracted widespread attention in recent years due to their synthetic simplicity, biocompatibility, and unique photoluminescent behavior. In this work, water-soluble silicon–carbon dots (SiCDs) were synthesized, and their properties were evaluated. First, a series of SiCDs was prepared by using a novel magnetic hyperthermia method from citric acid (CA) and 3-(2-aminoethylamino) propyldimethoxymethylsilane (AEAMPS). Then, based on the Stöber method, silica (SiO₂) was loaded onto the SiCDs in a one-pot reaction to obtain SiCDs@SiO₂ microspheres. This synthesis strategy is safe, efficient, and simple, allowing gram-scale production in a short time. The resulting SiCDs@SiO₂ microspheres exhibited excellent fluorescent performance, along with high water solubility and independence of excitation fluorescence. The SiCDs@SiO₂ microspheres possessed good thermal resistance and acid–base stability. The influence of storage time and different metal ions on the microsphere suspension was minimal. The SiCDs@SiO₂ microspheres show potential applications for water detection in horizontal wells as fluorescent markers. Full article

Uric acid (UA), the final metabolic product of purines, plays a crucial role in human health monitoring. The UA concentration in biological fluids serves as a diagnostic marker for various disorders, particularly kidney diseases, and represents a potential therapeutic target. Given the growing emphasis on preventive healthcare, developing methods for real-time UA detection has become increasingly significant. Here, we demonstrate the synthesis of novel tumbleweed-like molybdenum diselenide (MoSe₂) nanostructures through a single-step hydrothermal process. The synthesized MoSe₂ was subsequently hybridized with reduced graphene oxide (rGO) to construct electrodes for UA sensing. Differential pulse voltammetry (DPV) measurements revealed that the MoSe₂/rGO-modified glassy carbon electrode (GCE) exhibited excellent UA detection capabilities under optimized conditions. The sensor demonstrated a remarkably low limit of detection (LOD) of 28.4 nM and maintained linearity across a wide concentration range (40 nM to 200 μM). Notably, the sensor showed high selectivity for UA detection even in the presence of common interfering species, including citric acid (CA), dopamine (DA), ascorbic acid (AA), cysteine (Cys), glucose (Glu), oxalic acid (OA), sodium ions (Na⁺), and potassium ions (K⁺). The developed sensor displayed outstanding selectivity, stability, and reproducibility characteristics. This synthetic approach offers promising opportunities for developing MoSe₂-based electrochemical sensing platforms suitable for diverse bioanalytical applications. Full article

Meringue has limited the use of meringue for personalization because of its thermally unstable system. Citric acid (CA) enhancement of egg white protein (EWP) foaming properties is proposed for the preparation of 3D-printed meringues. The results showed that CA increased the viscosity, exposure of hydrophobic groups (79.8% increase), and free sulfhydryl content (from 5 µmol/g to 34.8 µmol/g) of the EWP, thereby increasing the foaminess (from 50% to 178.2%). CA treatment increased the rates of adsorption, stretching, and orientation of EWP at the air–water interface to form multiple layers, resulting in a delay in foam thinning. The secondary structure of CA-treated EWP remained intact, and the exposure of amino acid residues in the tertiary structure increased with the expansion of the hydrophobic region. CA-treated EWP-prepared protein creams had a suitable viscosity (from 233.4 Pa·s to 1007 Pa·s at 0.1 s⁻¹), shear thinning, structural restorability, and elasticity, which ensured good fidelity of their printed samples. Experiments involving 3D printing of CA-treated EWP showed that CA could significantly enhance the 3D printing fidelity of EWP. Our study could provide new ideas for the development of customizable 3D-printed foam food products. Full article

This work demonstrates the preparation of fast-swelling hydrogels based on poly(vinyl alcohol) (PVA) and tamarind xyloglucan (XG), utilizing freeze-drying to achieve an interconnected macroporous structure. Although XG is non-toxic and abundant, it has poor mechanical properties. Therefore, XG was mixed with PVA and crosslinked with citric acid (CA). Without XG, the crosslinked PVA sample contained partially aligned channels several hundred microns wide. The addition of XG (25% w/w) reduced the structural order of the hydrogels. However, the addition of XG improved the swelling ratio from 308 ± 19% in crosslinked PVA to 533.33% in crosslinked PVA/XG. XG also increased the porosity, as the porosity of the crosslinked PVA, XG, and PVA/XG samples was 56.09 ± 2.79%, 68.99 ± 2.06%, and 66.49 ± 1.62%, respectively. Resistance to compression was decreased by the incorporation of XG but was increased by CA crosslinking. The determination of the gel fraction revealed that CA crosslinking was more effective for the PVA component than the XG component. The swelling of all hydrogels was very rapid, reaching equilibrium within 10 s, due to the interconnected macroporous structure that allowed for capillary action. In conclusion, the prepared hydrogels are non-cytotoxic and well suited for biomedical applications such as drug delivery, wound dressings, and hygienic products. Full article