RESUMEN
Nanoparticles of green materials have gained enormous interest due to their broad range of applications in several disciplines since they have significantly improved multifunctional activities. This article attempts a sustainable green approach to synthesize sodium lignosulfonate nanoparticles (SLS NPs) using another biomolecule, i.e., chitosan. The synthesized SLS NPs (with an average diameter of ~125 nm to 129 nm) have demonstrated synergetic efficacy by exhibiting outstanding multifunctional properties due to the presence of two types of biomolecules (i.e., lignosulfonate as well as chitosan) in their structure. The synthesized SLS NPs have bestowed excellent antibacterial activity against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. Moreover, SLS NPs have displayed ~92% antioxidant property. Having polyphenolic entities in the structure of SLS NPs, they have shown UV-visible absorption peak at 224 nm, which directly indicates that they can act as an outstanding UV protective agent which has also been proven experimentally.
Asunto(s)
Quitosano , Nanopartículas del Metal , Nanopartículas , Antibacterianos/química , Antibacterianos/farmacología , Quitosano/química , Escherichia coli , Tecnología Química Verde , Lignina/análogos & derivados , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Sodio , Staphylococcus aureusRESUMEN
The worldwide resurgence of natural dyes in all fields is due to the carcinogenic effects of effluent loads shed by synthetic industries. Coconut coir (Cocos nucifera) containing tannin as a source of natural colorants has been selected for coloration of bio-mordanted silk under the influence of ultrasonic radiations at various dyeing conditions. For extraction of tannin dye from cocos powder, different media were employed, and dyeing variables such as dyeing time, dye bath pH, dyeing bath temperature, and the effect of salts on dyeing were optimized. For achieving new shades with excellent color characteristics, bio-mordants in comparison with chemical mordants were employed. It has been found that acid-solubilized extract after ultrasonic treatment for 45 min has yielded high color strength, when coconut coir extract of 4 pH from 6g of cocos powder, containing 5g/100mL salt solution as exhaust agent, was used to dye silk at 75°C for 65 min. Among bio-mordants turmeric (K/S=13.828) and among chemical mordants iron has shown excellent results (K/S=2.0856). Physiochemical analysis of fabric before and after US treatment shows that there is no change in the chemical structure of the fabric. It is found that ultrasonic waves have excellent potential to isolate the colorant followed by dyeing and environmental friendly mordanting at optimal conditions, but also the usage of herbal-based plant anchors, i.e., bio-mordants, has made the natural dyeing process more sustainable and clean.
Asunto(s)
Colorantes , Seda , Cocos , Lignina/análogos & derivados , Extractos VegetalesRESUMEN
Lignosulfonate (LS) is a by-product obtained during sulfite pulping process and is commonly used as a growth enhancer in plant growth. However, the underlying growth promoting mechanism of LS on shoot growth remains largely unknown. Hence, this study was undertaken to determine the potential application of eco-friendly ion-chelated LS complex [sodium LS (NaLS) and calcium LS (CaLS)] to enhance recalcitrant indica rice MR 219 shoot growth and to elucidate its underlying growth promoting mechanisms. In this study, the shoot apex of MR 219 rice was grown on Murashige and Skoog medium supplemented with different ion chelated LS complex (NaLS and CaLS) at 100, 200, 300 and 400 mg/L The NaLS was shown to be a better shoot growth enhancer as compared to CaLS, with optimum concentration of 300 mg/L. Subsequent comparative proteomic analysis revealed an increase of photosynthesis-related proteins [photosystem II (PSII) CP43 reaction center protein, photosystem I (PSI) iron-sulfur center, PSII CP47 reaction center protein, PSII protein D1], ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), carbohydrate metabolism-related proteins (glyceraldehyde-3-phosphate dehydrogenase 3, fructose-bisphosphate aldolase) and stress regulator proteins (peptide methionine sulfoxide reductase A4, delta-1-pyrroline-5-carboxylate synthase 1) abundance in NaLS-treated rice as compared to the control (MSO). Consistent with proteins detected, a significant increase in biochemical analyses involved in photosynthetic activities, carbohydrate metabolism and protein biosynthesis such as total chlorophyll, rubisco activity, total sugar and total protein contents were observed in NaLS-treated rice. This implies that NaLS plays a role in empowering photosynthesis activities that led to plant growth enhancement. In addition, the increased in abundance of stress regulator proteins were consistent with low levels of peroxidase activity, malondialdehyde content and phenylalanine ammonia lyase activity observed in NaLS-treated rice. These results suggest that NaLS plays a role in modulating cellular homeostasis to provide a conducive cellular environment for plant growth. Taken together, NaLS improved shoot growth of recalcitrant MR 219 rice by upregulation of photosynthetic activities and reduction of ROS accumulation leading to better plant growth.
Asunto(s)
Lignina/análogos & derivados , Oryza/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Brotes de la Planta/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Sodio/farmacología , Antioxidantes/metabolismo , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Clorofila/metabolismo , Lignina/farmacología , Oryza/metabolismo , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Proteínas de Plantas/metabolismo , Brotes de la Planta/metabolismo , Proteómica/métodos , Ribulosa-Bifosfato Carboxilasa/metabolismo , Azufre/metabolismoRESUMEN
Basal diets supplemented with 4 kg Ca-LS/ton of diet. Pellet quality characteristics (per cent fines, the present study was conducted to evaluate the influence of wheat middlings (WM) and calcium lignosulfonate (Ca-LS) as pellet binders on the pellet quality characteristics, growth performance, blood parameters, nutrients digestibilities, lipid peroxidation and muscle fatty acids profile in Egyptian broiler strain. A total of 3,120 broiler chicks at 1-day of age were divided randomly into three experimental treatments with eight replicates (130 each). The first treatment was fed the basal pelleted diets without any additives, the second treatment was fed diets including 50 kg WM/ton of diet and the third treatment was fed per cent pellets, and pellet durability index) were significantly improved in WM and Ca-LS treatments compared with the control. Body weight gain was significantly increased, while feed intake was significantly decreased resulting in improving of feed conversion ratio significantly in WM group in comparison with control and Ca-LS groups (p < .05). Nutrients apparent digestibility (dry matter, crude protein and crude fibre) were significantly improved by inclusion of WM compared with control and Ca-LS. Plasma total cholesterol, and uric acid concentrations were significantly decreased by dietary WM in comparison with control and Ca-LS experimental groups. Furthermore, linoleic, alpha-linolenic and arachidonic acids contents in breast muscle were significantly increased by WM and Ca-LS, while, muscle malondialdehyde concentration was significantly decreased. It could be concluded that inclusion of WM and Ca-LS can improve pellet quality characteristics, and WM (at a level of 50 kg/ton) had positive effects on growth performance, nutrients digestibilities, lipid peroxidation and fatty acids profile in Egyptian broiler strain.
Asunto(s)
Alimentación Animal/análisis , Pollos/fisiología , Lignina/análogos & derivados , Peroxidación de Lípido/efectos de los fármacos , Triticum/química , Animales , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Lignina/administración & dosificación , Lignina/metabolismo , Distribución AleatoriaRESUMEN
Hibiscus Rosasinensis L. extract mediated biosynthesis of Pd nanoparticles (NPs) and their deposition on the magnetic calcium lignosulfonate (MCaLig), as a simple and eco-friendly process for the preparation of Pd NPs@Fe3O4-lignin, is reported. The Pd NPs@Fe3O4-lignin was characterized by TEM, XRD, EDS, FE-SEM, FT-IR, VSM, and UV-Vis. The magnetic NPs were employed as exceptional catalysts in the catalytic reduction of Cr(VI) and Suzuki-Miyaura reaction between PhB(OH)2 and substituted aryl halides in EtOH:H2O as well as under ligand free conditions in the presence of K2CO3 with satisfactory product yields. Regeneration of the Pd NPs@Fe3O4-lignin was carried out by a magnet after the preparation of biphenyls. Catalytic efficiency retention was achieved after seven cycles.
Asunto(s)
Cromo/química , Compuestos Férricos/química , Hibiscus/química , Lignina/química , Nanopartículas/química , Paladio/química , Extractos Vegetales/química , Compuestos de Bifenilo/química , Catálisis , Tecnología Química Verde/métodos , Lignina/análogos & derivados , Magnetismo/métodos , Hojas de la Planta/química , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
This study aimed to evaluate the metabolic, productive, and carcass parameters of feedlot lambs fed high-concentrate diets with cottonseed associated with calcium lignosulfonate. Treatments consisted of diets including whole cottonseed, crushed cottonseed, whole cottonseed with lignosulfonate (100 g/kg), crushed cottonseed with lignosulfonate (100 g/kg), and a control diet without cottonseed. Thirty ½ Dorper ½ Santa Inês, non-castrated male lambs with an average live weight of 24.9 ± 3.6 kg and an average age of 3.5 months were evaluated in a completely randomized design. There was no effect (P > 0.05) on the intakes of dry matter, organic matter, crude protein, and non-fibrous carbohydrates. The crushing of cottonseed and association with lignosulfonate increased (P < 0.01) the intake and digestibility of ether extract. No effect was observed (P > 0.05) for the concentrations of urine and plasma urea N, which averaged 616.2 and 108.6 mg/dL, respectively. There was a change (P < 0.01) in nitrogen balance for digested N in g/day. There was no effect (P > 0.05) on the urinary concentration of purine derivatives, except for uric acid excretions (P < 0.05). Lignosulfonate associated with cottonseed provided an average daily gain of 0.293 kg/day, which was higher than the 0.226 kg/day obtained without lignosulfonate, but lower than control (0.302 kg/day), which also showed higher values of carcass yield. High-concentrate diets formulated without cottonseed improve lamb production performance. The use of high-concentrate diets with cottonseed associated with calcium lignosulfonate provides greater weight gains in lambs.
Asunto(s)
Dieta/veterinaria , Gossypium , Lignina/análogos & derivados , Semillas , Oveja Doméstica/crecimiento & desarrollo , Alimentación Animal/análisis , Animales , Nitrógeno de la Urea Sanguínea , Aceite de Semillas de Algodón , Masculino , Ovinos , Oveja Doméstica/metabolismo , Aumento de PesoRESUMEN
In this study, a technology for obtaining functional inorganic-organic hybrid materials was designed using waste polymers of natural origin, i.e., kraft lignin and magnesium lignosulfonate, and alumina as an inorganic component. Al2O3-lignin and Al2O3-lignosulfonate systems were prepared by a mechanical method using a mortar grinder and a planetary ball mill, which made it possible to obtain products of adequate homogeneity in an efficient manner. This was confirmed by the use of Fourier transform infrared spectroscopy and thermogravimetric analysis. In the next step, the developed hybrid materials were used as functional admixtures in cement mixtures, thus contributing to the formation of a modern, sustainable building material. How the original components and hybrid materials affected the mechanical properties of the resulting mortars was investigated. The admixture of biopolymers, especially lignin, led to cement composites characterized by greater plasticity, while alumina improved their strength properties. It was confirmed that the system containing 0.5 wt.% of alumina-lignin material is the most suitable for application as a cement mortar admixture.
Asunto(s)
Lignina/química , Materiales Manufacturados/análisis , Óxido de Aluminio/química , Biopolímeros/química , Lignina/análogos & derivados , Magnesio/química , Espectroscopía Infrarroja por Transformada de Fourier , TermogravimetríaRESUMEN
Two experiments were conducted to evaluate the effects of different types and levels of mixer-added fat (soybean oil: SO and calcium fat powder: CFP) and pellet binders (PBs: calcium lignosulfonate (CaLS) and bentonite (Ben)) on physical pellet quality (PPQ) parameters. PPQ included pellet durability index (PDI), pellet hardness, and pellet length of broiler diets processed under short-term conditioning. The first experiment had 4 treatments arranged as a 2 × 2 factorial with 2 types (SO and CFP) and 2 levels (1.5 and 3%) of mixer-added fat. In the second experiment, 22 treatments, combinations of 2 types of mixer-added fat (SO and CFP) at 3 levels (0, 1.5 and 3%) and 2 types of PB (CaLS = 0, 0.5, and 1% and Ben = 0, 1, and 2%), were arranged by a completely randomized design. PDI was measured by 2 devices: Pfost Tumbling box (PDIT) and Holmen NHP tester (PDIH). The results showed that the diets containing 1.5% CFP without PB had significant differences in all PPQ parameters. The results revealed that adding 0.5% CaLS to the 3% SO diets significantly enhanced PDIH, pellet hardness, and pellet length compared to other treatments. Moreover, 1.5% CFP diets with 2% Ben had significantly higher PDIT, PDIH, and pellet hardness among the treatments. Based on contour plots, different levels of Ben in the diets containing SO failed to create optimum PDIT values (>96%). However, 1.5 to 2.50% CFP diets without Ben had the optimum PDIT values. The optimum PDIT value was achieved by the diets containing 3% SO in the range of 0.21 to 0.56% CaLS. Furthermore, adding 0.5% CaLS to the diets containing less than 2.86% SO resulted in suboptimal PDIT values (<96%). The diets containing 1.5 to 2.50% CFP without CaLS had the optimum PDIT values. However, increasing CaLS levels more than 0.38% led to suboptimal PDIT values. Overall, these results indicated that the selection of appropriate PBs should be based on type and level of mixer-added fat.
Asunto(s)
Alimentación Animal/análisis , Bentonita/análisis , Pollos , Dieta/veterinaria , Grasas de la Dieta/análisis , Lignina/análogos & derivados , Animales , Calcio/análisis , Lignina/análisis , Polvos/análisis , Aceite de Soja/análisisRESUMEN
The fungi associated with termites secrete enzymes such as laccase (multi-copper oxidase) that can degrade extracellular wood matrix. Laccase uses molecular oxygen as an electron acceptor to catalyze the degradation of organic compounds. Owing to its ability to transfer electrons from the cathodic electrode to molecular oxygen, laccase has the potential to be a biocatalyst on the surface of the cathodic electrode of a microbial fuel cell (MFC). In this study, a two-chamber MFC using the laccase-producing fungus Galactomyces reessii was investigated. The fungus cultured on coconut coir was placed in the cathode chamber, while an anaerobic microbial community was maintained in the anode chamber fed by industrial rubber wastewater and supplemented by sulfate and a pH buffer. The laccase-based biocathode MFC (lbMFC) produced the maximum open circuit voltage of 250 mV, output voltage of 145 mV (with a 1,000 Ω resistor), power density of 59 mW/m2, and current density of 278 mA/m2, and a 70% increase in half-cell potential. This study demonstrated the capability of laccase-producing yeast Galactomyces reessii as a biocatalyst on the cathode of the two-chamber lbMFC.
Asunto(s)
Fuentes de Energía Bioeléctrica/microbiología , Reactores Biológicos , Electrodos/microbiología , Lacasa/metabolismo , Saccharomycetales/metabolismo , Bacterias Anaerobias/crecimiento & desarrollo , Bacterias Anaerobias/metabolismo , Biocatálisis , Fuentes de Energía Bioeléctrica/economía , Reactores Biológicos/economía , Reactores Biológicos/microbiología , Cocos , Conservación de los Recursos Naturales , Electricidad , Diseño de Equipo , Lignina/análogos & derivados , Lignina/metabolismo , Oxígeno/metabolismo , Goma , Saccharomycetales/crecimiento & desarrollo , Aguas del Alcantarillado/microbiología , Sulfatos/metabolismoRESUMEN
This study aimed to evaluate the effect of calcium lignosulfonate associated with whole cottonseed in high-concentrate diets for sheep. Eight Dorper crossbred sheep with an average live weight of 42.5 ± 1.70 kg were assigned to two 4 × 4 Latin squares. The following experimental diets were evaluated: control diet (without calcium lignosulfonate) and diets with inclusion of 50, 100, and 150 g of calcium lignosulfonate/kg fresh matter. Diets were composed of soybean meal, ground corn, and whole cottonseed. Feed intake, digestibility, metabolic characteristics, and feeding behavior were evaluated. The intake of nutritional components did not show significant differences as a function of the lignosulfonate levels in the diet; however, the increase in calcium lignosulfonate levels linearly decreased the dry matter digestibility. Rumen ammonia nitrogen concentrations decreased linearly as the lignosulfonate levels in the diets were increased. There was no effect of lignosulfonate levels on blood parameters or feeding behavior of the animals. The use of lignosulfonate associated with cottonseed decreases the digestibility of dry matter and the concentration of rumen ammonia nitrogen, but does not change the intake of nutritional components, the blood parameters, or the feeding behavior of sheep.
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Dieta/veterinaria , Lignina/análogos & derivados , Amoníaco/metabolismo , Alimentación Animal , Animales , Aceite de Semillas de Algodón , Digestión/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Lignina/administración & dosificación , Rumen/efectos de los fármacos , Rumen/metabolismo , Ovinos , Glycine max , Zea maysRESUMEN
Lentinula edodes mycelia solid culture extract (MSCE) is used as a medical food ingredient and provides beneficial effects to patients with cancer and chronic type C hepatitis. Low molecular weight lignin (LM-lignin), which is an active component of MSCE, exhibits hepatoprotective, antitumor, antiviral, and immunomodulatory effects. In this study, we investigated the effect of LM-lignin/lignosulfonic acid on intestinal barrier function. Lignosulfonic acid enhanced transepithelial membrane electrical resistance in human intestinal Caco-2 cell monolayers. In Caco-2 cells treated with lignosulfonic acid, expression of claudin-2, which forms high conductive cation pores in tight junctions (TJs), was decreased. Lignosulfonic acid also attenuated the barrier dysfunction that is caused by tumor necrosis factor (TNF)-α and interferon (IFN)-γ in Caco-2 cells. TNF-α- and IFN-γ-induced activation of NF-κB, such as translocation of NF-κB p65 into the nucleus and induction of gene expression, was inhibited by lignosulfonic acid treatment. Furthermore, lignosulfonic acid decreased the TNF-α- and IFN-γ-induced increase in interleukin (IL)-1ß and IL-6 expression in Caco-2 cells. These results suggest that lignosulfonic acid not only enhances TJ barrier function but also restores TJ barrier integrity impaired by inflammatory cytokines. Therefore, lignosulfonic acid may be beneficial for the treatment of inflammation-induced intestinal barrier dysfunction observed in inflammatory bowel disease.
Asunto(s)
Células Epiteliales/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Lignina/análogos & derivados , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Células CACO-2 , Línea Celular Tumoral , Humanos , Lignina/farmacología , Lignina/uso terapéutico , Transducción de Señal , TransfecciónRESUMEN
We report a novel room-temperature synthesis of selenium nanoparticles, which for the first time uses lignosulfonate as a stabilizer. Various lignosulfonates obtained both from hardwood and softwood were tested. Selenium oxide was used as the precursor of zero-valent selenium. Three different reducers were tested - sodium borohydride, hydrazine and ascorbic acid - and the latter proved most effective in terms of the particle size and stability of the final colloid. The lignosulfonate-stabilized selenium nanoparticles had a negative zeta potential, dependent on pH, which for some lignosulfonates reached -50mV, indicating the excellent stability of the colloid. When spherical silica particles were introduced to the synthesis mixture, selenium nanoparticles were deposited on their surface. Additionally, star-like structures consisting of sharp selenium needles with silica cores were observed. After drying, the selenium-functionalized silica had a grey metallic hue. The method reported here is simple and cost-effective, and can be used for the preparation of large quantities of selenium colloids or the surface modification of other materials with selenium.
Asunto(s)
Lignina/análogos & derivados , Nanopartículas/química , Selenio/química , Dióxido de Silicio/química , Lignina/química , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
A challenge in recent years has been the rational use of forest and agriculture residues for the production of bio-fuel, biochemical, and other bioproducts. In this study, potentially useful compounds from pyrolytic lignins were identified by HPLC-MS/MS and untargeted metabolomics. The metabolites identified were 2-(4-allyl-2-methoxyphenoxy)-1-(4-hydroxy-3-methoxyphenyl)-1-propanol, benzyl benzoate, fisetinidol, phenyllactic acid, 2-phenylpropionic acid, 6,3'-dimethoxyflavone, and vanillin. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH), trolox equivalent antioxidant capacity (TEAC), and total phenolics content (TPC) per gram of pyrolytic lignin ranged from 14 to 503 mg ascorbic acid equivalents, 35 to 277 mg trolox equivalents, and 0.42 to 50 mg gallic acid equivalents, respectively. A very significant correlation was observed between the DPPH and TPC (r = 0.8663, p ≤ 0.0001), TEAC and TPC (r = 0.8044, p ≤ 0.0001), and DPPH and TEAC (r = 0.8851, p ≤ 0.0001). The polyphenolic compounds in the pyrolytic lignins which are responsible for radical scavenging activity and antioxidant properties can be readily profiled with HPLC-MS/MS combined with untargeted metabolomics. The results also suggest that DPPH, TEAC, and TPC assays are suitable methods for the measurement of antioxidant activity in a variety of pyrolytic lignins. These data show that the pyrolytic lignins can be considered as promising sources of natural antioxidants and value-added chemicals.
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Antioxidantes/química , Antioxidantes/farmacología , Lignina/química , Lignina/farmacología , Biopolímeros/química , Biopolímeros/farmacología , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , Lignina/análogos & derivados , Metaboloma , Metabolómica/métodos , Fenoles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Análisis de Componente Principal , Espectrometría de Masas en TándemRESUMEN
Four new compounds, a dibenzylbutane lignin, plasiaticine F (1), an acetylenic glycoside, plasiaticine G (2), an indole alkaloid, plasiaticine H (3), and an ionone derivative, plasiaticine I (4), were isolated from the seeds of Plantago asiatica. The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data. Compounds 1-3 were tested for their cytotoxicity, but lacked significant activity.
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Lignina/análogos & derivados , Plantago/química , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Lignina/química , Lignina/aislamiento & purificación , Células MCF-7 , Estructura Molecular , Semillas/químicaRESUMEN
Microbial oil is drawing increasing interest worldwide as an alternative non-food oil feedstock for biodiesel industry. Nowadays researchers have been increasingly focused on the improvement of microbial oil production process. Oleaginous yeast Rhodosporidium toruloides (R. toruloides) is considered an important candidate due to its excellent capabilities of lipid accumulation, broad adaptabilities to various carbon substrates, and the potential of co-production of some pigments. In present work, the individual effects of non-ionic, cationic, and anionic surfactant on cell growth and lipid accumulation of R. toruloides were investigated for the first time. Interesting results were noticed when some anionic surfactants were supplemented. The most significant effect was observed with addition of 0.2 % (w/v) sodium lignosulfonate, that biomass concentration, lipid concentration, and lipid yield was increased by 25.1, 44.9, and 15.7 %, respectively. The fatty acid compositions of R. toruloides lipids remained unchanged, which is similar to that of vegetable oils, and is considered potential feedstock for biodiesel preparation.
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Basidiomycota/efectos de los fármacos , Basidiomycota/metabolismo , Lípidos/biosíntesis , Tensoactivos/farmacología , Basidiomycota/crecimiento & desarrollo , Biomasa , Carbono/metabolismo , Ácidos Grasos/metabolismo , Fermentación , Lignina/análogos & derivados , Lignina/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Pigmentos Biológicos/biosíntesis , Tensoactivos/químicaRESUMEN
The macromolecule sodium lignosulfonate (SL) has been investigated as dispersing agent for aqueous alumina colloids as a renewable alternative to usual petrochemical stabilizing agents. Optimization of the SL concentration necessary to stabilize the alumina suspension at different pH values was determined by viscometer. The results showed that addition of 250 ppm of the total suspension mass led to about 70% viscosity reduction of the suspension, whereas zeta potential analysis revealed negative values for the SL suspensions throughout the pH range investigated, suggesting that the alumina particles were covered by negatively charged SL molecules. Particle size investigation informed that the average particle diameter of the SL suspensions was smaller compared to that of the pristine particles. Sedimentation time for the SL suspensions was dramatically longer than that for the pristine one. The reported data strongly corroborated that SL is a suitable renewable dispersing agent for aqueous alumina colloids.
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Óxido de Aluminio/química , Lignina/análogos & derivados , Concentración de Iones de Hidrógeno , Lignina/química , Tamaño de la Partícula , Porosidad , ViscosidadRESUMEN
A method to enumerate labile hydrogens in all constituents of molecular ensemble of natural organic matter (NOM) based on our previously developed simple hydrogen/deuterium (H/D) exchange (electrospray ionization (ESI) ion source (Kostyukevich et al. Anal. Chem. 2013, 85, 5330) and ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry is presented. The method was applied for analysis of Suwannee River fulvic acid (SRFA), which is an International Humic Substances Society standard, as well as Siberian crude oil; and lignosulfonate. We found that SRFA and lignosulfonate molecules contain 2-5 labile hydrogens, and their number increases with the number of oxygens in the molecule. Also, we observed that compounds of Siberian crude oil ionizing in positive-ESI mode do not have labile hydrogens, while compounds ionizing in negative-ESI mode have one labile hydrogen that detaches during ESI ionization.
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Ciclotrones , Deuterio/química , Análisis de Fourier , Agua Dulce/análisis , Sustancias Húmicas/análisis , Hidrógeno/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Benzopiranos/análisis , Lignina/análogos & derivados , Lignina/análisis , Petróleo/análisisRESUMEN
With the aim to establish a novel nanocarrier system with relatively high payload and high photoprotection capacity for photo-labile active compounds, in this work, deltamethrin (photo-labile compound) was encapsulated into corn oil-nanoemulsions (NE) by a hot high pressure homogenization technique followed by coating with chitosan as the first coating layer (CH-NE) and lignosulfonate as the second coating layer to form a double-layer coated NE (L-CH-NE). The optimal conditions for preparation of NE, chitosan coating and lignosulfonate coating were investigated. The results indicate that polymer coating and the number of coating layers significantly affected the release profile and photoprotection capacity of nanocarriers. In particular, after coating, the release rate became slower and photoprotection capacity became higher. Moreover, in the case of L-CH-NE after 24h of UV exposure in direct photolysis and 2.5h of UV exposure in indirect photolysis, the non-degraded amount of deltamethrin was approximately 4.5 times and 2.1 times, respectively, higher than that of the free-from deltamethrin. In the future, this novel nanocarrier system will show great potential and be widely applied to many fields related to protection of photo-labile compounds against photo-degradation.
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Quitosano/química , Insecticidas/química , Lignina/análogos & derivados , Nanopartículas/química , Nitrilos/química , Piretrinas/química , Protectores contra Radiación/química , Aceite de Maíz/química , Emulsiones , Insecticidas/efectos de la radiación , Lignina/química , Nitrilos/efectos de la radiación , Tamaño de la Partícula , Fotólisis , Piretrinas/efectos de la radiación , Rayos UltravioletaRESUMEN
Hemp, hay, straw for animal litters, raffia and sisal stems, abaca and jute bleached pulp fibres, miscanthus stems and flax fibres were mixed to lignosulfonate at 70% filler concentration and compressed in the form of 5 cm-thick boards. Flax was found to give the best mechanical properties measured in bending mode and used for all tests. Several methods able to improve adhesion between matrix and flax fibres were studied. A treatment of flax fibres with NaOH-water was found to decrease the mechanical properties of composites. Ethanol or dichloromethane solvents that are known to dewax flax fibre surfaces improve the mechanical properties of final board. The addition of pectin to the lignosulfonate matrix was found to improve the mechanical properties in the same order of magnitude as with the ethanol treatment. Both methods improve the flexural strength by 60% while keeping the elastic modulus constant. Mechanical improvement shows that these two methods are increasing the lignosulfonate/flax fibre interfacial adhesion. The best compositions have mechanical properties above the normalized minimum required for wood-based boards.
Asunto(s)
Celulosa/química , Lino/química , Lignina/análogos & derivados , Madera/química , Fenómenos Biomecánicos , Cannabis/química , Celulosa/análisis , Módulo de Elasticidad , Etanol/química , Lino/anatomía & histología , Lignina/química , Microscopía Electrónica de Rastreo , Pectinas/química , Tallos de la Planta/anatomía & histología , Tallos de la Planta/químicaRESUMEN
The structure of the isolated milled "wood" lignin from coconut coir has been characterized using different analytical methods, including Py-GC/MS, 2D NMR, DFRC, and thioacidolysis. The analyses demonstrated that it is a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin, with a predominance of G units (S/G ratio 0.23) and considerable amounts of associated p-hydroxybenzoates. Two-dimensional NMR indicated that the main substructures present in this lignin include ß-O-4' alkyl aryl ethers followed by phenylcoumarans and resinols. Two-dimensional NMR spectra also indicated that coir lignin is partially acylated at the γ-carbon of the side chain with p-hydroxybenzoates and acetates. DFRC analysis showed that acetates preferentially acylate the γ-OH in S rather than in G units. Despite coir lignin's being highly enriched in G-units, thioacidolysis indicated that ß-ß' resinol structures are mostly derived from sinapyl alcohol. Finally, we find evidence that the flavone tricin is incorporated into the coconut coir lignin, as has been recently noted for various grasses.