Search Results (94)

Acidity is a primary factor leading to the deterioration of paper-based cultural heritage, and deacidification treatment is a crucial preventive conservation measure for extending their lifespan. Traditional deacidification techniques, such as the particle suspension method and vapor phase method, have limitations in terms of penetration uniformity, treatment efficacy, or safety. Nanoscale alkaline materials, represented by nano-calcium hydroxide and nano-magnesium hydroxide, offer an innovative solution with the potential to achieve more uniform, efficient, and long-lasting paper deacidification, owing to their high specific surface area, enhanced reactivity, and superior penetration capacity derived from the nanoscale dimension. It is important to note that the realized uniformity and depth of treatment are contingent upon substrate properties (e.g., fiber density, porosity) and application parameters. This paper provides a systematic review of the main types of nanomaterials applied in the deacidification of paper artifacts—including their synthesis and dispersion stabilization methods—application techniques (such as immersion and spraying) and performance evaluation systems (including pH value, alkaline reserve, and mechanical properties). Through comparative analysis and case studies, the advantages and current challenges of nano-deacidification technology are elaborated. Finally, future directions for nano-deacidification technology are discussed, particularly focusing on material optimization, standardized evaluation, and prospects for scalable application tailored to the practical needs of cultural heritage conservation. Full article

The manuscript concerns modern methods of preserving historical papers and presents research focusing on the effectiveness of paper strengthening with gelatin, Klucel G, and Tylose solutions in combination with deacidification using magnesium hydroxide nanoparticles. The aim of these procedures is to extend the durability of historical records on papers, which are an important part of humanity’s cultural heritage. Gelatin and Klucel G dissolved in propyl alcohol were used simultaneously with the dispersion of Mg(OH)₂ nanoparticles, and Tylose dissolved in water was applied after deacidification in a separate step. The experiments were conducted on Whatman model papers, artificially acidified or covered with iron gall ink. The evaluation of the effectiveness was based on tests of breaking length, changes in the DP_visc of cellulose, and pH of the aqueous extracts. Additional information was provided by microscopic examinations (SEM-EDX-SE) and measurements of the optical properties of the tested papers before and after the application of strengthening agents. All the strengthening agents tested increased paper strength—Tylose to the greatest extent, followed by Gelatin, and Klucel G to the least extent. Model papers covered with Klucel G showed good dimensional stability. Gelatin-covered papers showed the greatest changes in optical properties. Full article

Energy production from burning biomass in bioheat plants involves the production of biomass fly ash (BFA). Due to its rich chemical composition, in the era of a circular economy, it should be reused, for example, for environmental purposes as a secondary raw material containing valuable macro- and micronutrients. Due to its alkaline nature, it can also be an alternative to commercial agricultural lime (CAL) for neutralizing the acidic reaction of agricultural soils. The basis for the presented research was a pot experiment with corn (Zea mays L.) as a test plant and increasing doses of BFA (16.20, 32.40, and 48.60 g pot⁻¹), which is equal to 6.99, 13.98, and 20.97 g of CAL pot⁻¹. The above doses were determined based on the neutralization value (NV) of BFA and CAL, calculated to neutralize the hydrolytic acidity of the soil (Hh) to 0.5, 1.0, and 1.5 Hh. The study analyzed the effect of BFA on the leaf greenness index (SPAD), plant height, yield, and chemical composition of corn, as well as macronutrient content. The observations indicate that BFA application positively modified the yield of both fresh mass and dry mass of corn and height of plants, and reduced the dry matter content compared to the effect obtained after CAL use. BFA caused a decrease in the total N and Ca content and a significant increase in P, K, and Na compared to the CAL-fertilized treatments. BFA significantly contributed to a narrowing of the Ca:P, Ca:Mg ratios, and a widening of the K:(Ca + Mg), and K:Ca ratios compared to the ionic balance observed in the CAL-fertilized corn. The obtained results allow us to conclude that fly ash from biomass combustion can be a valuable alternative to conventional soil deacidification agents used till now in agriculture. Full article

It is well-known that EGF binding to EGFR stimulates signal transduction and endocytosis, with the latter leading to lysosomal degradation of EGFR. However, the majority of data on the regulation of endocytosis have been obtained in tumor-derived cells. Here, we perform a comprehensive analysis of the role of endolysosome acidification in the regulation of endocytic pathway in tumor cells and in endometrial MSCs as a model of proliferating, undifferentiated, non-immortalized cells. Using QD-labeled EGF, the dynamics of co-localization of EGF-receptor complexes with endocytic markers in the control and upon inhibition of V-ATPase by Bafilomycin A1 (BafA1) were studied using confocal microscopy. Image analysis showed that in HeLa and A549 cells, BafA1 significantly slowed down EGFR entry into and exit from EEA1-positive early endosomes without disrupting passage through Rab7, CD63, and Lamp1 compartments, but rather shifting it to later times. In enMSCs, only a portion of EGF-containing endosomes entered the degradation pathway, and lysosomal delivery was significantly delayed. Unlike HeLa, in enMSC early endosomes, BafA1 increased the association of EGF-QDs with EEA1, suggesting a lower pH level, which is suboptimal for EEA1-dependent fusions. It is concluded that, unlike HeLa, enMSCs form a population of pH-independent endosomes containing activated EGFR for a long time. Full article

Malolactic fermentation (MLF), a key enological process for wine deacidification and aroma and flavor development, is predominantly mediated by lactic acid bacteria. This study characterized 342 indigenous Lactiplantibacillus plantarum (L. plantarum) isolates, a potential starter species underexploited for MLF, from China’s Jiaodong Peninsula wine regions through polyphasic analysis. Thirty strains with high tolerance to wine stress conditions and efficient malate metabolism were selected. Among these, two high-performance strains, P101 and J43, exhibited superior MLF kinetics. Their applications had almost no effect on the wine’s basic physicochemical parameters, color parameters, and individual phenolic contents. Solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) analysis revealed that these strains significantly enhance key aroma compound contents in wines, including ethyl acetate, ethyl lactate, ethyl 2-methylbutyrate, and nerol, contributing more floral and fruity aroma characteristics. These indigenous L. plantarum strains, novel microbial starter cultures, demonstrate dual functionality in enhancing wine quality through controlled fermentation while supporting microbial biodiversity through the development of region-specific strain resources. Full article

As the principal dietary source of lipids, edible oils (notably vegetable oils) exist in crude form predominantly as triacylglycerols (about 95%), with the remainder comprising impurities and diverse minor components. Therefore, the refining processes of vegetable oil are particularly important. The application potential of safflower seed oil (SSO) in both nutraceutical and pharmaceutical domains is attributed to its exceptionally high linoleic acid concentration and abundant polyphenolic constituents. However, a systematic analysis of SSO during physical refining has yet to be conducted. This study aims to investigate the effects of refining processes on the fatty acids of SSO compared with flaxseed oil (FSO). In this study, chemical analysis, gas chromatography and ultra-high-performance liquid chromatography were used to analyze and compare the physicochemical indexes, fatty acid composition, and the lipidomics of SSO and FSO. Results indicated that optimized refining significantly enhances quality parameters in both SSO and FSO. A total of 40 and 43 fatty acids were identified in SSO and FSO, respectively. Deacidification significantly altered their fatty acid profiles, particularly polyunsaturated fatty acids, with C18:2 and C18:3 being the most affected. A total of 20 significantly different lipids were screened (variable importance in projection > 1.5, p < 0.05) and were mainly classified as glycerophospholipids and glycerolipids, of which two lipids (C18:2 and C18:3 (9, 12, 15)) demonstrated particularly marked differences, suggesting that these lipid species represent significant discriminators between SSO and FSO groups; these two lipids exhibited significant alterations during the refining processes of SSO and FSO, respectively. Full article

The scientific community’s interest in natural compounds with antiviral properties has considerably increased after the emergence of the severe acute respiratory syndrome coronavirus (SARS-CoV-2), especially for their potential use in the treatment of the COVID-19 infection. From this perspective, bovine coronavirus (BCoV), member of the genus β-CoV, represents a valuable virus model to study human β-CoVs, bypassing the risks of handling highly pathogenic and contagious viruses. Pimarane diterpenes are a significant group of secondary metabolites produced by phytopathogenic fungi, including several Diplodia species. Among the members of this class of natural products, sphaeropsidin A (SphA) and its analog sphaeropsidin B (SphB) are well known for their bioactivities, such as antimicrobial, insecticidal, herbicidal, and anticancer. In this study, the antiviral effects of SphA and SphB were evaluated for the first time on bovine (MDBK) cells infected with BCoV. Our findings showed that both sphaeropsidins significantly increased cell viability in infected cells. These substances also caused substantial declines in the virus yield and in the levels of the viral spike S protein. Interestingly, during the treatment, a cellular defense mechanism was detected in the downregulation of the aryl hydrocarbon receptor (AhR) signaling, which is affected by BCoV infection. We also observed that the presence of SphA and SphB determined the deacidification of the lysosomal environment in infected cells, which may be related to their antiviral activities. In addition, in silico investigations have been performed to elucidate the molecular mechanism governing the recognition of bovine AhR (bAhR) by Sphs. Molecular docking studies revealed significant insights into the structural determinants driving the bAhR binding by the examined compounds. Hence, in vitro and in silico results demonstrated that SphA and SphB are promising drug candidates for the development of efficient therapies able to fight a β-CoV-like BCoV during infection. Full article

The aim of this study is to evaluate the effectiveness of deacidifying treatments for the restoration of textiles used as supports for works of art, with particular attention to the chemical stability, colour variation and mechanical resistance of the materials over time. The present study involved the analysis of two products: Bookkeeper^TM, containing magnesium oxide, and Nanorestore^TM, a dispersion of calcium hydroxide in alcoholic solutions of ethanol and 2-propanol. The products were applied to a series of tests on cotton, linen and jute fabrics. The experimental approach comprised an artificial degradation process of the fabrics, followed by the application of the treatments and an accelerated ageing cycle. A series of parameters were monitored throughout the experiment, encompassing surface pH, chromatic shifts ascertained through colorimetric measurements and the morphological transformations of the fabrics, as elucidated by scanning electron microscopy (SEM-EDS). The findings yielded from this study have enabled the delineation of the behaviour exhibited by the treated materials over an extended timeframe. This underscores the significance of a judicious selection of treatments, contingent upon the particular chemical and physical attributes inherent to the fabrics in question. Full article

Macro- and microelements in waste can be returned to the soil as fertilizers and their sustainable use can reduce the need to extract natural resources. For example, the use of carbonate-clay flour, sewage sludge and waste sulfate sulfur to improve soil properties enables the natural recycling of the nutrients contained in these materials. Soil physicochemical properties with the application of waste and the bioavailability of nutrients and trace elements were assessed before and after a 3-month incubation period. This study showed that when carbonate-clay flour was applied alone or together with sewage sludge and waste sulfur, it improved the properties of the soil, inducing a reduction in acidification and an increase in the content of available P, K and Mg. Sewage sludge also provided Zn, Cu, Ni and Cr in addition to organic carbon. Sulfate did not cause soil acidification. The results indicate that the use of carbonate-clay flour alone, as well as with the addition of sewage sludge and sulfate sulfur, can be recommended for the deacidification of soil and serve as a remediation tool for, for example, the precipitation of chemical pollutants. The valorization of the waste used fits into the circular economy approach. Full article

The resource utilization potential and environmental impact of fly ash from municipal solid waste incinerators (MSWIs) have attracted wide attention. In this study, four MSWIs in Hangzhou, Zhejiang Province were selected to systematically evaluate the effects of different incinerator types and flue gas deacidification processes on fly ash’s oxide and heavy metal components and their temporal changes as well as conduct risk assessment. The results showed that the contents of MgO, Al₂O₃, SiO₂, and Fe₂O₃ in the grate furnace fly ash were significantly lower than those in the fluidized bed fly ash, but the compressive strength of its fly ash was high. Chemicals added during the flue gas deacidification process such as CaO and NaHCO₃ significantly affected the contents of CaO and Na₂O. In addition, heavy metals such as Cu, Mn, Cr, and Ni were mainly distributed in the fluidized bed fly ash, while heavy metals such as Pb and Cd were mainly collected in the grate furnace fly ash. The concentrations of various components in the fly ash fluctuated but were not significant under different time dimensions. Risk assessment indicated that heavy metals such as Cd, Pb, and Sb posed a high risk. This study is expected to provide theoretical support for the safe management and resource utilization of fly ash. Full article

This study explored the adsorption of carboxylic acids, especially free fatty acids (FFAs), present in biofuel (distilled fractions of bio-oil such as gasoline-like hydrocarbons, kerosene-like hydrocarbons, and diesel-like hydrocarbons) using red-mud-based adsorbents. The red mud was thermally activated at 40 °C and 600 °C and chemically activated with 0.25M, 1M, and 2M HCl. Analytical techniques were used to characterize the adsorbents’ properties. At the same time, the study examined factors like feed type, adsorbents, FFA contents, adsorbent percentage, activation temperature, acid solution concentration, and contact time to assess adsorption efficiency. The characterization results indicated that chemical activation with 0.25M HCl significantly increased the surface area to 84.3290 m²/g, surpassing that of the thermally activated samples (35.2450 m²/g at 400 °C). Adsorption experiments demonstrated that all chemically activated samples, with 5% adsorbent, adsorbed over 2000 mg of FFAs per gram of adsorbent, with CARM-1M HCl achieving 100% removal of acids from gasoline-like hydrocarbons. Kinetic modeling showed that the pseudo-second-order model best represented the adsorption data, as evidenced by high R² values and close agreement between the experimental and calculated q_e values. Therefore, adsorption with chemically activated red mud efficiently deacidifies biofuels, providing a cost-effective and promising approach for their upgrading. Full article

The FeZn-MOFs@Al₂O₃ catalyst was synthesized under solvothermal conditions. Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), temperature-programmed desorption of ammonia (NH₃-TPD), and specific Brunauer–Emmett–Teller (BET) surface area and pore volume were used to systematically investigate the effects of different parameters such as molar ratio of iron to zinc, synthesis temperature, and synthesis time on the properties of the materials. The results showed that the optimum synthesis conditions of FeZn-MOFs@Al₂O₃ composites were 140 °C for 1 h, and the optimum molar ratio of Fe³⁺ and Zn²⁺ was 1.3:0.7. Under the aforesaid conditions, FeZn-MOFs@Al₂O₃ had the deacidification rate of vacuum gas oil (VGO) up to 96.3%. The optimum esterification parameters were as follows: the amounts of catalyst and ethylene glycol were, respectively, 2.5 wt% and 4.0 wt% of the sample oil, the reaction temperature was 250 °C, and the reaction time was 1 h. Full article

Malolactic fermentation (MLF), an essential enological process for wine deacidification and aroma development, is predominantly mediated by Oenococcus oeni (O. oeni). This investigation characterized 170 indigenous O. oeni isolates from two principal Chinese viticultural regions (Yinchuan, Ningxia, and Changli, Hebei) through polyphasic analysis. Forty-nine strains demonstrating genetic potential for efficient malate metabolism and biosafety compliance (absence of ethyl carbamate and biogenic amines genes) were subjected to adaptive laboratory evolution under enologically relevant stress conditions. Comparative evaluation with the superior indigenous strain SD-2a revealed eight stress-adapted isolates exhibiting superior MLF kinetics, completing L-malic acid degradation in Marselan wine. Solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) profiling identified three isolates’ (3-31, 9-10, and 9-50) significant enhancement of key fermentation aromas in experimental fermentations. These oenologically adapted indigenous strains demonstrate promising potential as regional-specific starter cultures, providing a scientific foundation for developing terroir-expressive winemaking practices and optimizing microbial resources in China’s wine industry. Full article

Paper-based cultural relics experience aging and deterioration during their long-term preservation, which poses a serious threat to their lifetime. The development of conservation materials with high compatibility and low intervention has been expected to extend the lifetime of paper artifacts. As a new type of biological macromolecule, nanocellulose has been extensively utilized in paper conservation, attributed to its excellent paper compatibility, high optical transparency, outstanding mechanical strength, and large specific surface area with abundant hydroxyl groups. This review systematically summarizes the latest development of three kinds of nanocellulose (cellulose nanofibril, cellulose nanocrystal, and bacterial nanocellulose) and their composites used for the multifunctional conservation of paper relics. Owing to the strong hydrogen bond interactions between hydroxyls of nanocellulose and paper fibers, nanocellulose can effectively consolidate paper without adding adhesives. The composite of nanocellulose with other functional materials greatly expands its application scope, and the superior performance has been emphasized in paper deacidification, consolidation, antimicrobial effect, antioxidation, UV resistance, self-cleaning, promotion of printing property, reduction in air permeability, and flame retardancy. The application characteristics and future prospects of nanocellulose composites are highlighted in the conservation of paper-based cultural relics. Full article

Oil extracted from tiger nut is a good, edible source owing to its richness in unsaturated fatty acids. This study investigated the effects of the refining processes on the flavor components of crude tiger nut oil by GC-MS and focused on the thermal stability of the refined oil under high-temperature conditions. Three different refining processes were evaluated: citric acid-assisted hydration degumming, alkali deacidification and bleaching. In the present study, the neutralization refining resulted in 11.67% losses. The refined oil had higher brightness and transparency. Moreover, 109 volatiles were identified, mainly including aldehydes, alcohols, pyrazines and furans, the characteristic flavor compounds of which present a fatty, fresh and nutty flavor. Hence, the refining processes have a significant effect on the flavor components of tiger nut oil, and the accumulated information can be helpful in increasing the tiger nut oil quality to meet the market value. The results of the thermal properties indicated the significant degradation of oleic acid and linoleic acid with prolonged heating, leading to increases in the acid value by 17 times and the peroxide value by 31 times after prolonged heating at 210 °C for 10 h compared with those without heating. When the refined tiger nut oil was heated at 210 °C for 4 h, the carbonyl value (62.6 meq/kg) exceeded the recommended value, and after heating for 8 h, the total polar compound percentages (50%, the instrument limit value) also exceeded the national standard. In order to extend the cooking heating time, it is necessary to appropriately decrease the heating temperature. This study provides a scientific reference for the frying of tiger nut oil in food and the high-temperature treatment of food containing tiger nut oil. Full article