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1.
Int J Biol Macromol ; 277(Pt 3): 134339, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39089558

RESUMEN

Alpinia oxyphylla is famous for its neuroprotective and memory-improving effects. A crude polysaccharide AO70 from A. oxyphylla remarkably ameliorated neuroinflammation and cognitive dysfunction in Alzheimer's disease mice. This study aimed to explore the bioactive component of AO70 and its mechanism of action. A homogeneous polysaccharide (AOP70-1) rich in arabinose and xylose was purified from AO70, which was consisted of α-L-Araf-(1→, →5)-α-L-Araf-(1→, ß-D-Xylp-(1→,→2,4)-ß-D-Xylp-(1→, →2,3,4)-ß-D-Xylp-(1→, α-L-Rhap-(1→, α-D-Manp-(1→, →4)-α-D-Glcp-(1→, →4)-α-D-GlcpA-(1→, ß-D-Galp-(1→, →2)-α-D-Galp-(1→, →6)-α-D-Galp-(1 â†’ and →3,6)-α-D-Manp-(1 →. AOP70-1 (2.5, 5, 10 µM) significantly suppressed NO, IL-1ß, and TNF-α production in a concentration-dependent manner and inhibited the migration of BV2 microglia. AOP70-1 inhibited LPS-mediated activation of Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein (MyD88), and nuclear factor kappa B (NF-κB). Moreover, AOP70-1 exerted neuroprotection on SH-SY5Y cells and primary neurons by reducing neuronal apoptosis (72 %, 44 %), alleviating ROS accumulation (63 %, 55 %), and improving mitochondrial membrane potential (63 %, 77 %). Overall, AOP70-1 is one of the major bioactive components in AO70 from A. oxyphylla, which has great potential in the prevention and treatment of neuroinflammation.


Asunto(s)
Alpinia , Enfermedades Neuroinflamatorias , Transducción de Señal , Xilanos , Animales , Humanos , Ratones , Alpinia/química , Factor 88 de Diferenciación Mieloide/metabolismo , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Xilanos/farmacología , Xilanos/química , Xilanos/aislamiento & purificación
2.
Int J Biol Macromol ; 278(Pt 1): 134153, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39127270

RESUMEN

Hordeum vulgare husk, a cereal grain, is rich in dietary fiber and prebiotics beneficial for the gut microbiota and host organism. This study investigates the effects of barley husk-derived water-soluble xylan (BH-WSX) on gut homeostasis and the microbiome. We enzymatically extracted BH-WSX and evaluated its prebiotic and antioxidant properties. A 40.0 % (w/v) xylan yield was achieved, with the extracted xylan having a molecular mass of 212.0885 and a xylose to glucuronic acid molar ratio of 6:1. Specialized optical rotation research indicated that the isolated xylan is composed of monomeric sugars such as D-xylose, glucose, and arabinose. Fourier Transform Infrared (FTIR) spectroscopy revealed that the xylan comprises ß (1 â†’ 4) linked xylose units, randomly substituted with glucose residues, α-arabinofuranose, and acetyl groups. Nuclear Magnetic Resonance (NMR) analysis showed that the barley husk extract's backbone is substituted with 4-O-methyl glucuronic acid at the O2 position. Thermogravimetric analysis indicated that WSX exhibits a single sharp peak at 266 °C on the Differential Thermal Gravimetry (DTG) curve. Furthermore, a combination of in vitro, in vivo models, and molecular docking analysis elaborated on the anti-adhesion properties of BH-WSX. This study presents a novel approach to utilizing barley husk as an efficient source of functional polysaccharides for food-related industrial applications.


Asunto(s)
Hordeum , Hordeum/química , Polisacáridos/química , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Xilanos/química , Xilanos/farmacología , Xilanos/aislamiento & purificación , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Animales , Simulación del Acoplamiento Molecular
3.
Carbohydr Polym ; 342: 122399, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048235

RESUMEN

This work demonstrates that sesame (Sesamum indicum L.) hull, an unexploited food industrial waste, can be used as an efficient source for the extraction of hemicellulose and/or pectin polysaccharides to further obtain functional oligosaccharides. Different polysaccharides extraction methods were surveyed including alkaline and several enzymatic treatments. Based on the enzymatic release of xylose, arabinose, glucose, and galacturonic acid from sesame hull by using different enzymes, Celluclast®1.5 L, Pectinex®Ultra SP-L, and a combination of them were selected for the enzymatic extraction of polysaccharides at 50 °C, pH 5 up to 24 h. Once the polysaccharides were extracted, Ultraflo®L was selected to produce arabinoxylo-oligosaccharides (AXOS) at 40 °C up to 24 h. Apart from oligosaccharides production from extracted polysaccharides, alternative approaches for obtaining oligosaccharides were also explored. These were based on the analysis of the supernatants resulting from the polysaccharide extraction, alongside a sequential hydrolysis performed with Celluclast®1.5 L and Ultraflo®L of the starting raw sesame hull. The different fractions obtained were comprehensively characterized by determining low molecular weight carbohydrates and monomeric compositions, average Mw and dispersity, and oligosaccharide structure by MALDI-TOF-MS. The results indicated that sesame hull can be a useful source for polysaccharides extraction (pectin and hemicellulose) and derived oligosaccharides, especially AXOS.


Asunto(s)
Oligosacáridos , Sesamum , Sesamum/química , Oligosacáridos/química , Hidrólisis , Polisacáridos/química , Xilanos/química , Xilanos/aislamiento & purificación , Pectinas/química , Pectinas/aislamiento & purificación , Residuos Industriales , Arabinosa/química , Xilosa/química
4.
Int J Biol Macromol ; 190: 845-852, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34520781

RESUMEN

The xyloglucanase gene (RmXEG12A) from Rhizomucor miehei CAU432 was successfully expressed in Pichia pastoris. The highest xyloglucanase activity of 25,700 U mL-1 was secreted using high cell density fermentation. RmXEG12A was optimally active at pH 7.0 and 65 °C, respectively. The xyloglucanase exhibited the highest specific activity towards xyloglucan (7915.5 U mg-1). RmXEG12A was subjected to hydrolyze tamarind powder to produce xyloglucan oligosaccharides with the degree of polymerization (DP) 7-9. The hydrolysis ratio of xyloglucan in tamarind powder was 89.8%. Moreover, xyloglucan oligosaccharides (2.0%, w/w) improved the water holding capacity (WHC) of yoghurt by 1.1-fold and promoted the growth of Lactobacillus bulgaricus and Streptococcus thermophiles by 2.3 and 1.6-fold, respectively. Therefore, a suitable xyloglucanase for tamarind powder hydrolysis was expressed in P. pastoris at high level and xyloglucan oligosaccharides improved the quality of yoghurt.


Asunto(s)
Glucanos/biosíntesis , Glicósido Hidrolasas/metabolismo , Oligosacáridos/biosíntesis , Rhizomucor/enzimología , Saccharomycetales/metabolismo , Xilanos/biosíntesis , Yogur , Estabilidad de Enzimas , Glucanos/aislamiento & purificación , Glicósido Hidrolasas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Hidrólisis , Lactobacillus delbrueckii/crecimiento & desarrollo , Peso Molecular , Oligosacáridos/aislamiento & purificación , Streptococcus/crecimiento & desarrollo , Tamarindus/química , Temperatura , Factores de Tiempo , Xilanos/aislamiento & purificación
5.
Nutrients ; 13(6)2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34203983

RESUMEN

Arabinoxylan (AX) is a structural polysaccharide found in wheat, rice and other cereal grains. Diets high in AX-containing fiber may promote gut health in obesity through prebiotic function. Thus, the impact of soluble AX isolated from rice bran fiber on human gut microbiota phylogenetic composition and short-chain fatty acid (SCFA) production patterns from normal-weight and overweight/obese subjects was investigated through in vitro fecal fermentation. Results showed that rice bran arabinoxylan modified the microbiota in fecal samples from both weight classes compared to control, significantly increasing Collinsella, Blautia and Bifidobacterium, and decreasing Sutterella, Bilophila and Parabacteroides. Rice bran AX also significantly increased total and individual SCFA contents (p < 0.05). This study suggests that rice bran AX may beneficially impact gut health in obesity through prebiotic activities.


Asunto(s)
Heces/microbiología , Fermentación , Obesidad/microbiología , Oryza/química , Xilanos/metabolismo , Adulto , Bacterias/clasificación , Dieta , Carbohidratos de la Dieta , Fibras de la Dieta , Grano Comestible , Ácidos Grasos Volátiles , Femenino , Microbioma Gastrointestinal , Humanos , Masculino , Sobrepeso , Filogenia , Prebióticos , Triticum , Xilanos/aislamiento & purificación
6.
Carbohydr Polym ; 269: 118331, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34294341

RESUMEN

This study aimed to extract polysaccharides from citron and analyze their structures and potential bioactivities. Two novel polysaccharides CM-1 and CM-2 were purified from citron by DEAE-Sepharose Fast Flow and Sephadex G-100 column chromatography. Monosaccharide composition, linkage and NMR data were used to infer their sugar chains composition. The anti-breast cancer cells and immunoregulatory activities of CM-1 and CM-2 were investigated. Results indicated that CM-1 (Mw = 21,520 Da), composed of arabinose, xylose, mannose and glucose in a molar ratio of 10.78:11.53:1.00:1.70, was arabinoxylan (AX) with (1 â†’ 4)-linked ß-d-Xylp skeleton monosubstituted with α-l-Araf units at O-3 position. While CM-2 (Mw = 22,303 Da), composed of arabinose, mannose, glucose and galactose in a molar ratio of 25.46:1.45:1.00:6.57, was galactoarabinan (GA) with (1 â†’ 5)-linked α-l-Araf backbone substituted by ß-d-Galp units at O-2 and/or O-3 positions. Both polysaccharides exhibited potential inhibiting cancer and immunostimulatory activities in vitro, especially CM-1. These results provide a basis for further research on citron polysaccharides.


Asunto(s)
Antineoplásicos/farmacología , Citrus/química , Galactanos/farmacología , Factores Inmunológicos/farmacología , Xilanos/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/toxicidad , Secuencia de Carbohidratos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Galactanos/química , Galactanos/aislamiento & purificación , Galactanos/toxicidad , Humanos , Factores Inmunológicos/química , Factores Inmunológicos/aislamiento & purificación , Factores Inmunológicos/toxicidad , Interleucina-6/metabolismo , Ratones , Peso Molecular , Óxido Nítrico Sintasa de Tipo II/metabolismo , Células RAW 264.7 , Factor de Necrosis Tumoral alfa/metabolismo , Xilanos/química , Xilanos/aislamiento & purificación , Xilanos/toxicidad
7.
Molecules ; 26(10)2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-34069493

RESUMEN

Arabinoxylan (HBAX-60) was fractioned from alkaline-extracted arabinoxylan (HBAX) in the whole grain of hull-less barley (Hordeum vulgare L. var. nudum Hook. f. Poaceae) by 60% ethanol precipitation, which was studied for physicochemical properties and structure elucidation. Highly purified HBAX-60 mainly composed of arabinose (40.7%) and xylose (59.3%) was created. The methylation and NMR analysis of HBAX-60 indicated that a low-branched ß-(1→4)-linked xylan backbone possessed un-substituted (1,4-linked ß-Xylp, 36.2%), mono-substituted (ß-1,3,4-linked Xylp, 5.9%), and di-substituted (1,2,3,4-linked ß-Xylp, 12.1%) xylose units as the main chains, though other residues (α-Araf-(1→, ß-Xylp-(1→, α-Araf-(1→3)-α-Araf-(1→ or ß-Xylp-(1→3)-α-Araf-(1→) were also determined. Additionally, HBAX-60 exhibited random coil conformation in a 0.1 M NaNO3 solution. This work provides the properties and structural basis of the hull-less barley-derived arabinoxylan, which facilitates further research for exploring the structure-function relationship and application of arabinoxylan from hull-less barley.


Asunto(s)
Hordeum/química , Xilanos/química , Xilanos/aislamiento & purificación , Espectroscopía de Resonancia Magnética/métodos , Metilación , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier/métodos
8.
Carbohydr Polym ; 263: 117932, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33858566

RESUMEN

According to the high interest in agro-industrial waste reutilisation, underutilised lignocellulosic materials, such as walnut shell (WS) and pea pod (PP), come in focus. The aim of this paper was to evaluate WS and PP as sources for the production of xylooligosaccharides (XOS). Hemicelluloses from WS and PP were recovered by combining varying parameters of delignification and alkaline extraction. At optimal recovery conditions, the fractions were further hydrolysed to XOS using GH11 endo-xylanase, by varying time and enzyme concentration. Xylose was predominant in the monomeric composition of the obtained hemicelluloses, building low-branched (arabino)glucuronoxylan, in WS exclusively, while in PP some xyloglucan as well. Delignification was essential for high recovery of total xylose from the materials, up to at least 70 %. High xylan conversions were obtained for 24 h hydrolysis, resulting in xylobiose and xylotriose when using low enzyme concentration, while in xylose and xylobiose with high enzyme concentration.


Asunto(s)
Fraccionamiento Químico/métodos , Glucuronatos/química , Juglans/química , Juglans/metabolismo , Oligosacáridos/química , Pisum sativum/química , Pisum sativum/metabolismo , Glucuronatos/aislamiento & purificación , Hidrólisis , Juglans/anatomía & histología , Oligosacáridos/aislamiento & purificación , Pisum sativum/anatomía & histología , Extractos Vegetales/química , Polisacáridos/química , Polisacáridos/metabolismo , Azúcares/análisis , Xilanos/química , Xilanos/aislamiento & purificación , Xilosa/análisis , Xilosa/aislamiento & purificación , Xilosa/metabolismo
9.
J Biosci Bioeng ; 131(6): 647-654, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33676868

RESUMEN

Xylan is the major hemicellulose present in sugarcane stem secondary cell walls. Xylan is composed of xylose backbone with a high degree of substitutions, which affects its properties. In the present study, the xylan from sugarcane tops (SCT) was extracted and characterized. Compositional analysis of xylan extracted from SCT (SCTx) displayed the presence of 74% of d-xylose residues, 16% of d-glucuronic acid residues and 10% of l-arabinose. High performance size exclusion chromatographic analysis of SCTx displayed a single peak corresponding to a molecular mass of ∼57 kDa. The Fourier transform infrared spectroscopic analysis of SCTx displayed the peaks corresponding to those obtained from commercial xylan. FESEM analysis of SCTx showed the granular and porous surface structure. Differential thermogravimetric analysis (DTG) of SCTx displayed two thermal degradation temperatures (Td) of 228°C, due to breakdown of the side chains of glucuronic acid and arabinose and 275°C, due to breakdown of xylan back bone. The presence of arabinose and glucuronic acid as a side chains was confirmed by the DTG and thermogravimetric analysis. The CHNS analysis of SCTx showed the presence of only carbon and hydrogen supporting its purity. The recombinant xylanase (CtXyn11A) from Clostridium thermocellum displayed a specific activity of 1394 ± 51 U/mg with SCTx, which was higher than those with commercial xylans. The thin layer chromatography and electrospray ionization mass spectroscopy analyses of CtXyn11A hydrolysed SCTx contained a series of linear xylo-oligosaccharides ranging from degree of polymerization 2-6 and no substituted xylo-oligosaccharides because of the endolytic activity of enzyme. The extracted xylan from SCT can be used as an alternative commercial substrate and for oligo-saccharide production.


Asunto(s)
Saccharum/química , Xilanos/aislamiento & purificación , Arabinosa/aislamiento & purificación , Arabinosa/metabolismo , Pared Celular/química , Pared Celular/metabolismo , Comercio , Industria de Alimentos , Ácido Glucurónico/aislamiento & purificación , Ácido Glucurónico/metabolismo , Hidrólisis , Oligosacáridos/aislamiento & purificación , Oligosacáridos/metabolismo , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Saccharum/metabolismo , Xilanos/química , Xilanos/metabolismo , Xilosa/aislamiento & purificación , Xilosa/metabolismo
10.
Food Chem ; 339: 128093, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33152881

RESUMEN

Hydrolysates of arabinoxylan extracted from wheat chaff were prepared using different enzymatic treatments with an emphasis on improvements in their anti-diabetic, antioxidant and functional characteristics. The extracted arabinoxylan was subjected to enzymatic hydrolysis using individual xylanase, arabinofuranosidase, and feruloyl esterase, and their combinations. In all obtained hydrolysates, peaks corresponding to molecular weight lower than 38 kDa were noticed, while non-hydrolysed arabinoxylan had only peaks corresponding to 580 and 38 kDa. Results indicated that applied enzymes could hydrolyse polymeric arabinoxylan while their synergistic actions successfully modified its structure reflecting in lowered viscosity. Besides, it has been observed that the synergistic actions of enzymes improved the biological activities of arabinoxylan more than twice. Chemometric classification analysis showed that synergistic enzymes' actions were predominantly responsible for the improvement of biological activities. It indicated that they might be a useful tool for diversification and enhancement of biological activities of arabinoxylan from wheat chaff.


Asunto(s)
Hidrolasas/metabolismo , Triticum/química , Xilanos/química , Xilanos/metabolismo , Hidrólisis , Peso Molecular , Viscosidad , Xilanos/aislamiento & purificación , Xilanos/farmacología
11.
Int J Biol Macromol ; 165(Pt A): 842-848, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33022347

RESUMEN

Many native plant biopolymers or derivatives thereof have interesting biological effects and therefore the search for additional biological activities is important to map their overall effects. A low molecular weight (Mw = 7600 g/mol) hemicellulose polymer α-L-arabino(4-O-methyl-α-D-glucurono)-ß-D-xylan (AGX) was isolated from the crushed roots of the Rudbeckia fulgida medicinal plant by alkaline extractions and anion-exchange chromatography. Analysis of neutral sugars revealed a predominance of xylose (82.3 wt%) and arabinose (6.8 wt%), while other neutral sugars were found only in small amounts as contaminants. The uronic acid content in Rudbeckia AGX was determined to be 8.8 wt%. Pharmacological tests showed that Rudbeckia AGX effectively suppressed cough and the initial amplitude of histamine/methacholine-induced bronchoconstriction in healthy OVA-sensitive guinea pigs. In addition, its effect at a dose of 100 mg/kg was similar to or greater than that of the positive control bronchodilator salbutamol and the antitussive codeine agent. These findings support the fact that Rudbeckia AGX could be a suitable candidate for alternative treatment of allergic asthma.


Asunto(s)
Antiasmáticos , Asma/tratamiento farmacológico , Raíces de Plantas/química , Rudbeckia/química , Xilanos , Animales , Antiasmáticos/química , Antiasmáticos/aislamiento & purificación , Antiasmáticos/farmacología , Asma/metabolismo , Asma/patología , Secuencia de Carbohidratos , Modelos Animales de Enfermedad , Cobayas , Humanos , Masculino , Xilanos/química , Xilanos/aislamiento & purificación , Xilanos/farmacología
12.
Carbohydr Polym ; 250: 116916, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33049888

RESUMEN

This study demonstrates the potential of feruloylated arabinoxylan (AX) from wheat bran for the preparation of bioactive barrier films with antioxidant properties. We have comprehensively evaluated the influence of the structural features and chemical acetylation of feruloylated AX extracted by subcritical water on their film properties, in comparison with alkaline extracted AX and a reference wheat endosperm AX. The degree of substitution (DS) of AX had a large influence on film formation, higher DS yielded better thermal and mechanical properties. The barrier properties of AX films were significantly enhanced by external plasticization by sorbitol. Chemical acetylation significantly improved the thermal stability but not the mechanical or barrier properties of the films. The presence of bound ferulic acid in feruloylated AX films resulted in higher antioxidant activity compared to external addition of free ferulic acid, which demonstrates their potential use in active packaging applications for the preservation of oxygen-sensitive foodstuff.


Asunto(s)
Ácidos Cumáricos/química , Fibras de la Dieta/análisis , Endospermo/química , Agua/química , Xilanos/química , Xilanos/aislamiento & purificación , Acetilación , Xilanos/metabolismo
13.
Int J Biol Macromol ; 163: 1897-1907, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32946939

RESUMEN

Xylan extracted from neem sawdust gave 22.5%, (w/w) yield. The extracted xylan was composed of xylose and glucuronic acid at a molar ratio of 8:1 and with a molecular mass, ~66 kDa. FTIR and NMR analyses indicated a backbone of xylan substituted with 4-O-methyl glucuronic acid at the O-2 position. FESEM analysis showed a highly porous and granular surface structure of xylan. A thermogravimetric study of xylan showed thermal denaturation at 271 °C. The hydrolysis of xylan by recombinant endo-ß-1,4-xylanase produced a mixture of xylooligosaccharides ranging from degree of polymerization 2-7. Xylooligosaccharides inhibited cell growth of human colorectal cancer (HT-29) cells but did not affect the mouse fibroblast cells confirming its biocompatibility. Western blotting, DNA laddering and flow cytometric analysis displayed inhibition of HT-29 cells by xylooligosaccharides. FLICA staining and mitochondrial membrane potential analyses confirmed the activation of the intrinsic pathway of apoptosis. The study amply indicated that the xylooligosaccharides produced from neem xylan could be potentially used as an antiproliferative agent.


Asunto(s)
Azadirachta/química , Proliferación Celular/efectos de los fármacos , Oligosacáridos/aislamiento & purificación , Xilanos/aislamiento & purificación , Neoplasias Colorrectales/tratamiento farmacológico , Células HT29 , Humanos , Hidrólisis , Oligosacáridos/química , Oligosacáridos/farmacología , Madera/química , Xilanos/química , Xilanos/farmacología , Xilosa/química
14.
Carbohydr Polym ; 246: 116544, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32747233

RESUMEN

Structurally different polymers were derived from Picea abies foliage by successive extraction with water (PAW), HCl solution (PAA) and (NH4)2C2O4 solution (PAO). The P. abies foliage was found to contain basically low-methoxyl pectin extractable with an (NH4)2C2O4 solution. PAW was shown to comprise primarily arabinogalactan-proteins (AGPs); PAA was composed of mixed AGPs and pectic polysaccharides, with the latter prevailing; and polysaccharide PAO isolated in the highest yield included chiefly pectic polysaccharides. The major constituents of PAO were low-methoxyl and low-acetylated 1,4-α-d-galacturonan and partially acetylated RG-I. The sugar side chains of RG-I contained chiefly highly branched 1,5-α-l-arabinan and arabinogalactan type I as a minor constituent. RG-I whose side chains had 1,5-α-l-arabinan represented short regions alternating with non-acetylated and unmethylesterified galacturonan regions. In addition to pectins, polysaccharide PAO contained AGPs, xylanes and glucomannans, indicating that these polysaccharides are in an intimate interaction.


Asunto(s)
Mananos/química , Oxalatos/química , Pectinas/química , Picea/química , Extractos Vegetales/química , Xilanos/química , Espectroscopía de Resonancia Magnética con Carbono-13/métodos , Ácido Clorhídrico/química , Hidrólisis , Mananos/aislamiento & purificación , Mucoproteínas/química , Pectinas/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Proteínas de Plantas/química , Solubilidad , Agua/química , Xilanos/aislamiento & purificación
15.
Biomolecules ; 10(9)2020 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-32854282

RESUMEN

Corn cob is an agricultural byproduct that produces an estimated waste burden in the thousands of tons annually, but it is also a good source of xylan, an important bioactive polysaccharide. Silver nanoparticles containing xylan (nanoxylan) were produced using an environmentally friendly synthesis method. To do this, we extracted xylan from corn cobs using an ultrasound technique, which was confirmed by both chemical and NMR analyses. This xylan contained xylose, glucose, arabinose, galactose, mannose, and glucuronic acid in a molar ratio of 50:21:14:9:2.5:2.5, respectively. Nanoxylan synthesis was analyzed using UV-vis spectroscopy at kmax = 469 nm and Fourier transform infrared spectroscopy (FT-IR), which confirmed the presence of both silver and xylan in the nanoxylan product. Dynamic light scattering (DLS) and atomic force microscopy (AFM) revealed that the nanoxylan particles were ~102.0 nm in size and spherical in shape, respectively. DLS also demonstrated that nanoxylan was stable for 12 months and coupled plasma optical emission spectrometry (ICP-OES) showed that the nanoxylan particles were 19% silver. Nanoxylan reduced Leishmania amazonensis promastigote viability with a half maximal inhibitory concentration (IC50) value of 25 µg/mL, while xylan alone showed no effective. Additionally, nanoxylan exhibited antifungal activity against Candida albicans (MIC = 7.5 µg/mL), C. parapsilosis (MIC = 7.5 µg/mL), and Cryptococcus neoformans (MIC = 7.5 µg/mL). Taken together, these data suggest that it is possible to synthesize silver nanoparticles using xylan and that these nanoxylan exert improved antileishmanial and antifungal activities when compared to the untreated polysaccharide or silver nitrate used for their synthesis. Thus, nanoxylan may represent a promising new class of antiparasitic agents for use in the treatment of these microorganisms.


Asunto(s)
Antifúngicos/síntesis química , Antiprotozoarios/síntesis química , Nanopartículas del Metal/química , Plata/química , Células 3T3 , Animales , Antifúngicos/química , Antiprotozoarios/química , Candida albicans/efectos de los fármacos , Candida parapsilosis/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Estabilidad de Medicamentos , Dispersión Dinámica de Luz , Excipientes/química , Excipientes/aislamiento & purificación , Tecnología Química Verde/métodos , Humanos , Leishmania mexicana/efectos de los fármacos , Nanopartículas del Metal/ultraestructura , Ratones , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Sustancias Reductoras/química , Sustancias Reductoras/aislamiento & purificación , Espectrofotometría , Xilanos/química , Xilanos/aislamiento & purificación , Xilanos/ultraestructura , Zea mays/química
16.
Food Chem ; 333: 127491, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32659672

RESUMEN

A cascade process for the sequential recovery of proteins and feruloylated arabinoxylan from wheat bran is proposed, involving a protein isolation step, enzymatic destarching and subcritical water extraction. The protein isolation step combining lactic acid fermentation and cold alkaline extraction reduced the recalcitrance of wheat bran, thus improving the total yields of the subsequent subcritical water extraction. The time evolution of subcritical water extraction of feruloylated arabinoxylan was compared at two temperatures (160 °C and 180 °C). Longer residence times enhanced the purity of target feruloylated arabinoxylans, whereas higher temperatures resulted in faster extraction at the expense of significant molar mass reduction. The radical scavenging activity of the extracted feruloylated arabinoxylans was preserved after the initial protein isolation step. This study opens new possibilities for the cascade valorization of wheat bran into enriched protein and non-starch polysaccharide fractions, which show potential to be used as functional food ingredients.


Asunto(s)
Fraccionamiento Químico/métodos , Ácidos Cumáricos/química , Fibras de la Dieta/análisis , Proteínas de Plantas/aislamiento & purificación , Xilanos/química , Xilanos/aislamiento & purificación , Calor , Peso Molecular
17.
Int J Biol Macromol ; 162: 1025-1034, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32599238

RESUMEN

A green synthesis of silver nanoparticles was synthesized by AgNO3 with arabinoxylan, isolated from green stem of Andrographis paniculata (Kalmegh). The synthesized Ag NPs-arabinoxylan conjugates were characterized by UV-vis spectroscopy, FE-SEM, TEM, XRD, TGA, EDX, and Zeta potential experiments. The Ag NPs formation was established by the surface plasmon resonance band ~410.25 nm. SEM image showed mostly spherical morphology of Ag NPs. The fcc crystalline nature was identified by XRD, SAED and the size were 24.5 and 25 nm from TEM and XRD analysis respectively. The prepared Ag NPs showed dose-dependent antimicrobial activity against Streptococcus pneumonia, Candida albicans and E. coli. The nanoparciles damage 4% hemolysis to human RBCs at 12.5 µg/mL. MTT assay of Ag NPs showed that half of the cell killed at 10 µg/mL and wound healing assay observed effective inhibition cell proliferation.


Asunto(s)
Acanthaceae/química , Antiinfecciosos , Candida albicans/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Nanopartículas del Metal/química , Streptococcus pneumoniae/crecimiento & desarrollo , Xilanos/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Tecnología Química Verde , Plata/química , Plata/farmacología , Xilanos/aislamiento & purificación
18.
Carbohydr Polym ; 241: 116317, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32507173

RESUMEN

Feruloylated arabinoxylans demonstrate great potential in developing natural materials through oxidative crosslinking. However, the common alkaline method to extract arabinoxylans causes heavy losses of feruloyl esters thus hinders the crosslinking activity. Highly feruloylated arabinoxylans were fractionated from wheat bran by an alternative method using subcritical water extraction (SWE) and were compared with water- and alkali-extracted arabinoxylans. Various yields, chemical compositions, and molecular weights were obtained as the SWE conditions changed. Methylation analysis showed that the SWE arabinoxylans had a similar linkage pattern as the water-extracted arabinoxylan. Laccase-induced oxidative crosslinking was investigated through dynamic rheology, finding a broad spectrum of gelling ability for the SWE arabinoxylans. Finally, the optimal condition (160 °C, pH 7 for 10 min) was used in a repeated SWE procedure to maximize the yield and crosslinking properties. The combination of subcritical water and enzymatic crosslinking presents as a promising green approach for preparing hydrogels from herbaceous hemicelluloses.


Asunto(s)
Fibras de la Dieta/análisis , Hidrogeles , Polisacáridos , Xilanos , Tecnología Química Verde , Hidrogeles/química , Hidrogeles/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Xilanos/química , Xilanos/aislamiento & purificación
19.
Carbohydr Polym ; 240: 116328, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32475586

RESUMEN

Feruloylated arabinoxylan (AX) is one of the most predominant dietary fiber in cereal grains. In recent decades, soluble AX has gained interest, as a result of its well-established health benefits. Apart from enzymatic degradation during cereal storage, food processing causes AX degradation. These reactions lead to structural modifications and influence both the AX functionalities and its health promoting effects. The aim of this study was to investigate the structural modifications and related property changes of health promoting water-extractable (WE) wheat bran AX through grain milling and extrusion. Multi-detector HPSEC revealed a correlation between Mw, conformational changes and the related viscosity behaviour depending on the processing type. Processing caused molecular degradation of insoluble high Mw AX, which increased the solubility significantly. Moreover, extrusion leaded to a more heterogenic AX fine structure. The detailed characterization of processed dietary fiber may help to facilitate the optimized incorporation of AX in health-promoting foods.


Asunto(s)
Fibras de la Dieta/análisis , Xilanos/aislamiento & purificación , Conformación de Carbohidratos , Grano Comestible/química , Manipulación de Alimentos , Solubilidad , Agua/química , Xilanos/química
20.
Biomed Pharmacother ; 126: 110064, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32278271

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world and one of the most lethal. MGN-3/Biobran is a natural product derived from rice bran hemicelluloses and has been reported to possess a potent anticancer effect in a clinical study of patients with HCC. The current study examines the mechanisms by which Biobran protects against chemically induced hepatocarcinogenesis in rats. The chemical carcinogen used in this study is N-nitrosodiethylamine (NDEA) plus carbon tetrachloride (CCl4). Rats were treated with this carcinogen, and the animals were pretreated or posttreated with Biobran via intraperitoneal injections until the end of the experiment. Treatment with Biobran resulted in: 1) significant alleviation of liver preneoplastic lesions towards normal hepatocellular architecture in association with inhibition of collagen fiber deposition; 2) arrest of cancer cells in the sub-G1 phase of the cell cycle; 3) increased DNA fragmentation in cancer cells; 4) down-regulated expression of Bcl-2 and up-regulated expression of p53, Bax, and caspase-3; and 5) protection against carcinogen-induced suppression of IkappaB-alpha (IκB-α) mRNA expression and inhibition of nuclear factor kappa-B (NF-κB/p65) expression. Additionally, the effect of Biobran treatment was found to be more significant when supplemented prior to carcinogen-induced hepatocarcinogenesis as compared to posttreatment. We conclude that Biobran inhibits hepatocarcinogenesis in rats by mechanisms that include induction of apoptosis, inhibition of inflammation, and suppression of cancer cell proliferation. Biobran may be a promising chemopreventive and chemotherapeutic agent for liver carcinogenesis.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinogénesis/efectos de los fármacos , Neoplasias Hepáticas Experimentales/prevención & control , Hígado/efectos de los fármacos , Xilanos/farmacología , Animales , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Carcinogénesis/genética , Carcinogénesis/patología , Ciclo Celular/efectos de los fármacos , Quimioprevención , Daño del ADN/efectos de los fármacos , Dietilnitrosamina/toxicidad , Hígado/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Masculino , Oryza/química , Ratas Wistar , Semillas/química , Xilanos/administración & dosificación , Xilanos/aislamiento & purificación
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