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1.
Molecules ; 28(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37959670

RESUMEN

Potato peel waste (PPW) was utilized as a bio-template for the production of valuable compounds such as reducing sugars (RS), total sugar (TS) and total phenolic compounds (TPC). Two methods of alkali treatments, i.e., chemical (NaOH) and thermochemical (NaOH assisted with autoclaving) processes, were employed for the deconstruction of PPW. Response surface methodology (RSM) was used to study the effects of alkali concentration (0.6-1.0 w/v), substrate concentration (5-15 g) and time (4-8 h) on the extraction of RS, TS and TP from PPW. The application of alkali plus steam treatment in Box-Behnken design (BBD) with three levels yielded the optimum releases of RS, TS and TP as 7.163, 28.971 and 4.064 mg/mL, respectively, corresponding to 10% substrate loading, in 0.6% NaOH for 8 h. However, the alkali treatment reported optimum extractions of RS, TS and TP as 4.061, 17.432 and 2.993 mg/mL, respectively. The thermochemical pretreatment was proven a beneficial process as it led to higher productions of TP. FTIR and SEM were used to analyze the deterioration levels of the substrate. The present work was used to explore the sustainable management of PPW, which is a highly neglected substrate bioresource but is excessively dumped in open environment, raising environmental concerns. The cost-effective methods for the breakdown of PPW starch into fermentable sugars might be utilized to extract valuable compounds.


Asunto(s)
Solanum tuberosum , Solanum tuberosum/química , Azúcares/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Hidróxido de Sodio , Almidón/metabolismo
2.
Molecules ; 28(14)2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37513183

RESUMEN

Trans-p-hydroxycinnamic acid and its esters in the leaves of Ligustrum robustum might be a new resource to prevent diabetes and its complications. In the present study, a new HPLC-UV method using hydrolyzation with sodium hydroxide for quantitation of trans-p-hydroxycinnamic acid and total trans-p-hydroxycinnamic acid esters in the leaves of L. robustum was developed, since it was difficult and troublesome to analyze no less than 34 trans-p-hydroxycinnamic acid esters by usual HPLC. The extract of L. robustum was hydrolyzed with sodium hydroxide at 80 °C for 2 h, and then, hydrochloride was added. HPLC analysis was performed in reverse phase mode using a C-18 column, eluting with methanol-0.1% acetic acid aqueous solution (40:60, v/v) in isocratic mode at a flow rate of 1.0 mL·min-1 and detecting at 310 nm. The linear range for trans-p-hydroxycinnamic acid was 11.0-352.0 µg·mL-1 (r2 = 1.000). The limit of detection and limit of quantification were 2.00 and 6.07 µg·mL-1, respectively. The relative standard deviations of intra-day and inter-day variabilities for trans-p-hydroxycinnamic acid were less than 2%. The percentage recovery of trans-p-hydroxycinnamic acid was 103.3% ± 1.1%. It is the first HPLC method using hydrolyzation for quantification of many carboxylic esters. Finally, the method was used successfully to determine trans-p-hydroxycinnamic acid and total trans-p-hydroxycinnamic acid esters in various extracts of the leaves of L. robustum. The 60-70% ethanol extracts of L. robustum showed the highest contents of free trans-p-hydroxycinnamic acid (3.96-3.99 mg·g-1), and the 50-80% ethanol extracts of L. robustum displayed the highest contents of total trans-p-hydroxycinnamic acid esters (202.6-210.6 mg·g-1). The method can be applied also to the quality control of the products of L. robustum.


Asunto(s)
Ligustrum , Hidróxido de Sodio , Cromatografía Líquida de Alta Presión/métodos , Ésteres , Extractos Vegetales , Hojas de la Planta
3.
Toxicol Rep ; 10: 104-116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36685271

RESUMEN

Despite the widespread use of silver nanoparticles (NPs), these NPs can accumulate and have toxic effects on various organs. However, the effects of silver nanostructures (Ag-NS) with alginate coating on the male reproductive system have not been studied. Therefore, this study aimed to investigate the impacts of this NS on sperm function and testicular structure. After the synthesis and characterization of Ag-NS, the animals were divided into five groups (n = 8), including one control group, two sham groups (received 1.5 mg/kg/day alginate solution for 14 and 35 days), and two treatment groups (received Ag-NS at the same dose and time). Following injections, sperm parameters, apoptosis, and autophagy were analyzed by the TUNEL assay and measurement of the mRNA expression of Bax, Bcl-2, caspase-3, LC3, and Beclin-1. Fertilization rate was assessed by in vitro fertilization (IVF), and testicular structure was analyzed using the TUNEL assay and hematoxylin and eosin (H&E) staining. The results showed that the NS was rod-shaped, had a size of about 60 nm, and could reduce sperm function and fertility. Gene expression results demonstrated an increase in the apoptotic markers and a decrease in autophagy markers, indicating apoptotic cell death. Moreover, Ag-NS invaded testicular tissues, especially in the chronic phase (35 days), resulting in tissue alteration and epithelium disintegration. The results suggest that sperm parameters and fertility were affected. In addition, NS has negative influences on testicular tissues, causing infertility in men exposed to these NS.

4.
Saudi J Biol Sci ; 29(3): 1644-1652, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35280576

RESUMEN

This study aimed to evaluate the efficacy of chitosan-silver nanocomposites in the treatment of experimentally infested pigeons with Pseudolynchia canariensis (P. canariensis) with evaluation of different immunological parameters before and after treatment. Therefore, fourteen birds were divided into 2 groups; group1(infested group including 12 birds) which subdivided into 6 sub-groups experimentally infested pigeons 2 pigeons each, and five group of them were treated with chitosan-silver nanocomposites and sub-group number 6 was treated with deltamethrin while, group 2 including two pigeons were kept as control negative ones. P. canariensis flies distributed under the wing and /or under the tail in infested group and these pigeons showed significantly lower RBCs and higher WBCs than that in non-infested pigeons. The cell mediated immune response against experimentally infested pigeons with P. canariensis was studied. P. canariensis infestation in pigeons have a negative impact on pigeon's blood parameters, increase TNF-α and IL-1ß cytokines levels. This study cleared out the role of P. canariensis in the induction of a case of oxidative stress indicated by high level of nitric oxide and malondialdehyde (MDA) with low antioxidant capacity in shape of reduced zinc concentration in the sera of experimentally infested pigeon. Chitosan-silver nanocomposite has a promising effect in the elimination of P. canariensis infestation in pigeons.

5.
Mater Sci Eng C Mater Biol Appl ; 130: 112450, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34702529

RESUMEN

Chitosan/poloxamer-based thermosensitive hydrogels containing zinc gluconate/recombinant human epidermal growth factor (ZnG/rhEGF@Chit/Polo) were developed as a convenient, safe and effective dressing for skin wound treatment. Their fabrication procedure and characterization were reported, and their morphology was examined by a scanning electron microscope. Antibacterial and biofilms activities were evaluated by in vitro tests to reveal the inhibitory effects and scavenging activity on the biofilms of Staphylococcus aureus and Pseudomonas aeruginosa. ZnG/rhEGF@Chit/Polo was also investigated as a potential therapeutic agent for wound healing therapy. In vivo wound healing studies on rats for 21 days proves that ZnG/rhEGF@Chit/Polo supplements the requisite Zn2+ and rhEGF for wound healing to promote the vascular remodeling and collagen deposition, facilitate fibrogenesis, and reduce the level of interleukin 6 for wound basement repair, and thus is a good wound therapy.


Asunto(s)
Quitosano , Animales , Antibacterianos/farmacología , Quitosano/farmacología , Factor de Crecimiento Epidérmico , Gluconatos , Humanos , Hidrogeles/farmacología , Poloxámero , Ratas , Cicatrización de Heridas
6.
Food Chem ; 365: 130528, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34325350

RESUMEN

Mango bagasse (MB) is an agro-industrial by-product rich in bioactive polyphenols with potential application as a functional ingredient. This study aimed to delineate the metabolic fate of monomeric/polymeric MB polyphenols subjected to simulated gastrointestinal digestion. The main identified compounds by LC/MS-TOF-ESI were phenolic acids [gallic acid (GA) and derivates, and chlorogenic acid], gallotannins and derivatives [di-GA (DA) and 3GG-to-8GG], benzophenones [galloylated maclurins (MGH, MDH)], flavonoids [Quercetin (Quer) and (QuerH)] and xanthones [mangiferin isomers]. The bioaccessibility depended on the polyphenols' structure, being Quer, 5G to 8G the main drivers. The results suggested that the gastrointestinal fate of MB polyphenols is mainly governed by benzophenones and gallotannins degalloylation and spontaneous xanthone isomerization in vitro to sustain GA bioaccessibility.


Asunto(s)
Mangifera , Antioxidantes , Celulosa , Extractos Vegetales , Polifenoles
7.
J Insect Sci ; 21(4)2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34280293

RESUMEN

Protein and amino acids in pollen are important nutritional components for larval development in several insect species, especially in Apoidea. The Bradford assay is a widely used method to measure relative protein content of pollen, which can shed light on pollen quality and consequences to fitness. Prior to using the Bradford assay, protein must be released from pollen grains, often using a mixture of chemical and mechanical fracturation methods. In this study, we tested the efficacy of protein extraction without using mechanical fracturation. We used pollen collected by the solitary bee Osmia lignaria Say to compare two known buffers associated with pollen protein analysis: phosphate-buffered saline and sodium hydroxide, and deionized water, and with different pollen weights from which we quantified protein using the Bradford assay. While all buffers and deionized water were useful in releasing protein from pollen grains collected by O. lignaria, the use of sodium hydroxide resulted in significantly higher protein quantification across all pollen weights. This methodological study can inform future studies of pollen nutrition in pollen-foraging species.


Asunto(s)
Conducta Alimentaria , Polen/química , Aminoácidos/química , Aminoácidos/aislamiento & purificación , Animales , Abejas/fisiología , Proteínas/química , Proteínas/aislamiento & purificación , Análisis Espectral/métodos
8.
Carbohydr Polym ; 255: 117383, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33436212

RESUMEN

Cellulose nanofibrils were efficiently produced from eucalyptus fibers using a combined NaOH and enzymatic treatment followed by a pilot scale grinding process. The structural changes of fibers were assessed after NaOH treatments at 5, 10 and 15 wt% concentrations. A progressive shift from a cellulose I to a cellulose II crystalline structure was observed with X-ray diffraction (XRD) and nuclear magnetic resonance (NMR). The further enzymatic hydrolysis was improved for the NaOH treated samples. The increase of crystallinity indices due to enzymatic hydrolysis was of + 4.7 %, + 3.5 %, and +10.3 % for samples treated with NaOH 5, 10 and 15 wt% respectively, and DP values were drastically reduced to 340, 190 and 166 respectively. A morphological analysis underlined an optimum with the combination of NaOH 10 wt% and enzymatic hydrolysis. This treatment followed by the grinding process resulted in CNF with a rigid structure, with diameters ranging from 10 to 20 nm and lengths between 150 and 350 nm. A multi-scale analysis enabled to study the impact of this combined treatment on CNF properties and energy consumption. A decrease in mechanical properties of nanopapers was observed for the combined treatment and NaOH treatment alone compared to enzymatic hydrolysis alone, with Young's modulus of 8.94, 4.84 and 11.21 GPa respectively. However, optical properties were improved, with transmittance values of 42.2, 15.4 and 7.1 % respectively. This new pretreatment can therefore lead to CNF with tunable properties depending on the application, with possible industrialization thanks to the reduction of energy needs.


Asunto(s)
Celulosa/química , Eucalyptus/química , Nanofibras/química , Hidróxido de Sodio/química , Biomasa , Cristalización , Módulo de Elasticidad , Hidrólisis , Ensayo de Materiales/métodos , Nanofibras/ultraestructura
9.
J Microbiol Methods ; 175: 105968, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32479871

RESUMEN

The standard procedure for the improved cultural recovery of viable Mycobacterium spp. from diverse samples mainly depends on reducing the viability of background microbiota using different chemical compounds. This study was designed to i) evaluate the efficacy and comparison between N-Acetyl-l-Cysteine-Sodium hydroxide (NALC-2% NaOH) and hexadecylpyridinium chloride (0.75% HPC) treatment and exposure time on reducing the viability of undesirable microorganisms with minimal impact on colostrum consistency; and ii) assess the impact of NALC-2% NaOH on improved and enhanced recovery of Mycobacterium avium subsp. paratuberculosis (MAP) in spiked postpartum colostrum samples and consistency of colostrum. A total of 40 samples, each treated with NALC-2% NaOH for 15 min or 0.75% HPC for 5 h, were investigated for total mesophilic aerobic bacteria (MAB) and enterobacteria (EB) (CFU mL-1). The results showed that treatment of colostrum samples with NALC-2% NaOH completely eliminated EB and significantly reduced MAB (3.6 log10 CFU mL-1). Conversely, samples treated with 0.75% HPC produced a complex mixture following interaction with the colostrum protein and showed non-significant and variable results. In addition, the spiked colostrum treated with NALC-2% NaOH for 15 min revealed recovery of viable MAP cells with a minimum limit of detection of 1.36 log10 CFU 10 mL-1 where no change in the consistency of colostrum was observed. In conclusion, 15-min NALC-2% NaOH treatment of colostrum may significantly reduce the viability of undesirable microorganisms and help to enhance the efficient recovery of MAP without impacting the consistency of high quality postpartum colostrum. This rapid procedure is suitable for efficient recovery and early detection of MAP as well as preventing its transmission to neonates and young calves in MAP infected herds.


Asunto(s)
Enfermedades de los Bovinos , Calostro/microbiología , Descontaminación/métodos , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis , Acetilcisteína/química , Animales , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Cetilpiridinio/química , Femenino , Viabilidad Microbiana , Paratuberculosis/diagnóstico , Paratuberculosis/microbiología , Embarazo , Hidróxido de Sodio/química
10.
Food Res Int ; 133: 108707, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32466922

RESUMEN

A particular challenge to making wine from Pinot noir grapes is the delicate flavor, light color and poor ageing potential of the wine. Conventional Pinot noir must preparations were compared with those made using a skin-based supplement to assess the impact on non-bleachable (sulfur resistant) pigments in the wine. When supplemented with either fresh grape pomace of Pinot noir, Pinot gris or Chardonnay grapes; Pinot noir grape marc or a commercial liquid grape skin extract, the additional seeds and pulp from the supplements were shown to compromise the development of stable pigments in the wine. To compare the relative merits of tannin derived from grape skins and seeds, the supplements used in a parallel experiment were the skins alone of the same three grape varieties and at six months bottle age, the stable pigment concentration was found to exceed the amount attributable to the supplement. A third experiment used fermented grape skins as the supplement, with 85% of the supplementary anthocyanin recovered as stable pigment complexes in the wine. Notably, this series of experiments showed that supplements containing grape seeds appeared to compromise non-bleachable pigment formation in the wine while skin only supplements stimulated their development.


Asunto(s)
Pigmentación/efectos de los fármacos , Epidermis de la Planta/química , Semillas/química , Vitis , Vino , Antocianinas/análisis , Fermentación , Taninos/análisis
11.
Food Res Int ; 130: 108966, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32156400

RESUMEN

In this work, coated liposome as a novel delivery system assembled from genipin-crosslinked with whey protein isolate (WPI) and sodium alginate (SA) as the second layer on WPI-coated liposomal was developed in order to increase its bioavailability and prolong release for drug and nutraceuticals. Therefore, the influence of GP and SA on physico-chemical properties, long term stability and in vitro release behavior of WPI coated nanoliposomes (NLs) for encapsulation of flaxseed oil were investigated successively. Compared with WPI-NLs and uncoated NLs, GP-WPI-NLs and SA-WPI-NLs displayed more significant changes in average diameter, zeta potential, entrapment efficiency, morphology, FT-IR, thermal properties, with lower n-3 fatty acids released. In terms of physical and oxidative stability during storage at 45 °C for 30 days, the GP was remarkably more effective than the SA. The results suggested that the coating with SA and cross-linking with GP altered the surface properties, and provided more chemical stability for the flaxseed oil as core material.


Asunto(s)
Alginatos/química , Iridoides/química , Aceite de Linaza/química , Liposomas/química , Proteína de Suero de Leche/química , Reactores Biológicos , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
12.
Carbohydr Polym ; 229: 115405, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31826414

RESUMEN

The fruit of Alpinia oxyphylla is often used in traditional Chinese medicine to treat dementia and memory defects. In this study, we isolated a novel acidic polysaccharide (AOP70-2-1) from A. oxyphylla fruit. Structural analysis showed that AOP70-2-1 consists of ß-D-GlcAp-(1→, →2,3,6)-α-D-Galp-(1→, α-L-Araf-(1→, →2,5)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→, →3,4)-α-D-Xylp-(1→, →3,6)-ß-D-Manp-(1→, and α-L-Rhap-(1→. Morphological analysis indicated that AOP70-2-1 had an irregular sheet structure. The crude polysaccharide (AOP70) from A. oxyphylla significantly improved learning and memory ability of Alzheimer's disease (AD) mice, and AOP70 exhibited comparable or even better effects than huperzine A. Most important, AOP70 reduced NO, IL-1ß, TNF-α, and PGE-2 concentrations to normal levels. AOP70-2-1 significantly inhibited NO production in lipopolysaccharide stimulated BV2 microglial cells. Note that the effect of 2.6 µM AOP70-2-1 was superior to indomethacin. AOP70-2-1 also remarkably decreased the values of IL-6 and TNF-α. AOP70-2-1 may be a bioactive component of AOP70 and has the potential for the treatment of AD.


Asunto(s)
Alpinia , Enfermedad de Alzheimer/tratamiento farmacológico , Antiinflamatorios , Fármacos Neuroprotectores , Polisacáridos , Enfermedad de Alzheimer/sangre , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Línea Celular , Dinoprostona/sangre , Frutas , Interleucina-1beta/sangre , Masculino , Ratones , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Óxido Nítrico/sangre , Polisacáridos/química , Polisacáridos/farmacología , Factor de Necrosis Tumoral alfa/sangre
13.
J Environ Manage ; 255: 109824, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31747627

RESUMEN

Phosphorus (P) recovery from sludge has drawn widespread attention across the world to minimize the P load to the watershed, a concern for eutrophication, and to meet the stringent effluent discharge regulations in some countries. Waste activated sludge (WAS) and dewatered sludge (DS) were treated with a wide range of NaOH doses (0-0.75 g g-1 TS). The WAS sludge was diluted to 4.5%-2.25% of TS before the treatment to make comparable amount of TS as of DS (2.25%-1.5%). The kinetic study illustrated that P solubilization reached equilibrium within the first 20 min of treatment duration. Significant positive correlation was found between solution pH and P solubilization, whereas effect of TS was mostly insignificant. The experimental data was well fitted to the exponential models and exhibited maximum P solubilization of about 67% and 56% from the DS and WAS at NaOH doses of 0.71 and 0.27 g g-1 TS, respectively. The optimal NaOH application dose of 0.36 g g-1 TS for DS and 0.20 g g-1 TS for WAS were obtained with 64% and 48% of P solubilization, respectively. The modeling approach and the optimal dose of NaOH illustrated in this study could be utilized for other types of sludges having similar P to TS ratio and P solubilization mechanisms could be further extended to other type of P recovery techniques.


Asunto(s)
Fósforo , Aguas del Alcantarillado , Concentración de Iones de Hidrógeno , Hidróxido de Sodio , Eliminación de Residuos Líquidos
14.
Food Chem ; 295: 449-455, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31174781

RESUMEN

The aroma stability of fresh coffee brew was investigated during storage over 60 min, there was a substantial reduction in available 2-furfurylthiol (2-FFT) (84%), methanethiol (72%), 3-methyl-1H-pyrole (68%) and an increase of 2-pentylfuran (65%). It is proposed that 2-FFT was reduced through reversible chemical binding and irreversible losses. Bound 2-FFT was released after cysteine addition, thereby demonstrating that a reversible binding reaction was the dominant mechanism of 2-FFT loss in natural coffee brew. The reduction in available 2-FFT was investigated at different pH and temperatures. At high pH, the reversible binding of 2-FFT was shown to protect 2-FFT from irreversible losses, while irreversible losses led to the reduction of total 2-FFT at low pH. A model reaction system was developed and a potential conjugate, hydroxyhydroquinone, was reacted with 2-FFT. Hydroxyhydroquinone also showed 2-FFT was released after cysteine addition at high pH.


Asunto(s)
Café/química , Almacenamiento de Alimentos/métodos , Furanos/química , Odorantes/análisis , Compuestos de Sulfhidrilo/química , Furanos/análisis , Concentración de Iones de Hidrógeno , Compuestos de Sulfhidrilo/análisis , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química
15.
Food Chem ; 290: 125-134, 2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31000028

RESUMEN

To unravel prospective lactic acid bacteria (LAB) and yeasts with potential application in potato-based products, the microbial diversity of fermented potato was studied. High-throughput sequencing revealed that the 5 samples differ in microbial compositions resulting from nutrients modification by the pretreatment methods adopted. Weisella and Saccharomyces cerevisiae were found to be the dominant LAB and yeast in fermented potato respectively. The high abundance of Weisella (35.84%) and Gluconobacter (20.80%) in steamed fermented potato (SFP) resulted in lowering of pH (4.39 ±â€¯0.09) and inhibition of undesirable bacteria and fungi. Fermentation increased protein and dietary fiber contents of boiled fermented potato (BFP) and SFP, with highest protein content (8.18 ±â€¯0.22%) recorded in BFP. The dietary fiber contents of BFP and SFP are 9.68 ±â€¯0.68% and 9.48 ±â€¯0.37% respectively with no observable significant difference. This study provides information on microorganisms with potential benefits in quality enhancement of potato-based products.


Asunto(s)
Bacterias/genética , Biodiversidad , Fermentación , Hongos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Solanum tuberosum/metabolismo , Solanum tuberosum/microbiología , Bacterias/aislamiento & purificación , Fibras de la Dieta , Hongos/aislamiento & purificación
16.
Food Chem ; 289: 351-359, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30955623

RESUMEN

The ultrasound-microwave assisted HCl extraction of pectin from potato pulp was optimized using the response surface methodology. Effects of extraction temperature, pH, and time on the yield were evaluated, and structural characteristics of pectin extracted under optimal conditions were determined. The yield was 22.86 ±â€¯1.29% under optimal conditions of temperature 93 °C, pH 2.0, and time 50 min. The obtained pectin was rich in branched rhamnogalacturonan I (61.54 mol%). Furthermore, the pectin was a low-methoxyl (degree of methylation, 32.58%) but highly acetylated (degree of acetylation, 17.84%) pectin and the molecular weight was 1.537 × 105 g/mol. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance indicated that pectin had a linear region of α-1, 4-linked galacturonic acids which could be methyl and acetyl-esterified, and rhamnose linked with galacturonic acid to form rhamnogalacturonan which was branched with side chains. Scanning electron microscopy showed most of pectin had a lamellae structure.


Asunto(s)
Pectinas/aislamiento & purificación , Extractos Vegetales/química , Solanum tuberosum/química , Acetilación , Ácidos Hexurónicos/química , Metilación , Microscopía Electrónica de Rastreo , Microondas , Pectinas/análisis , Pectinas/química , Tubérculos de la Planta/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Ultrasonido
17.
Food Chem ; 286: 1-7, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30827581

RESUMEN

Surfactant and microwave assisted extraction (S-MAE) was used for pectin extraction from orange peel. First, we optimized the conditions of microwave assisted extraction (MAE), e.g., irradiation time, liquid-to-solid ratio (LSR), and pH on pectin yield (PY), galacturonic acid (GA) content, and degree of esterification (DE) using a Box-Behnken design. Under optimal conditions (pH 1.2, 7.0 min, and 21.5 v/w LSR), we obtained a PY of 28.0 ±â€¯0.5%, which was close to the predicted value (31.1%). Second, we analyzed the effect of surfactant on microwave extraction of pectin. Among the surfactants investigated, Tween-80 (8 g/L, w/v) increased PY by 17.0%. Compared with conventional solvent extraction, S-MAE is a novel and efficient method for pectin extraction, which generated a higher (p < 0.05) PY (32.8%), GA content (78.1%), DE (69.8%), and Mw (286.3 kDa).


Asunto(s)
Citrus sinensis/metabolismo , Microondas , Pectinas/química , Tensoactivos/química , Cromatografía Líquida de Alta Presión , Esterificación , Ácidos Hexurónicos/química , Concentración de Iones de Hidrógeno , Pectinas/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de Fourier
18.
Waste Manag ; 85: 295-303, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30803583

RESUMEN

Solid alcohols based on waste cooking oil (WCO) and other edible oils (butter or soybean oil) were synthesized by a simple one-step method. The effects of sodium hydroxide (NaOH) dosage and type of oil on the combustion performances were explored. IR spectroscopy and micro-morphologies of the oil based solid alcohols were also studied. Results showed that, for oil based solid alcohol, use of an appropriate excess of NaOH and an oil with lower iodine value produced the solid alcohol with better combustion performance. Centrifugation produced the bottom waste cooking oil (B-WCO) with lower iodine value and the supernatant waste cooking oil (S-WCO) with higher iodine value. The B-WCO afforded solid alcohol with longer combustion time, higher melting temperature and relatively low combustion residue rate, whereas the S-WCO could be used for synthesizing biodiesel.


Asunto(s)
Biocombustibles , Aceites de Plantas , Culinaria , Etanol , Alimentos
19.
Food Chem ; 284: 80-89, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-30744872

RESUMEN

In this study, alcalase and neutrase were used in combination to prepare collagen peptides with high calcium binding ability. The optimal conditions for the preparation of peptide-calcium chelate (mass ratio of peptide/calcium of 4.5:1 for 40 min at 50 °C and pH 9) were determined by response surface methodology (RSM), under which a calcium chelating rate of 78.38% was obtained. The results of Ultraviolet-Visible (UV-Vis), fluorescence and Fourier transform infrared (FT-IR) spectra synthetically indicated that calcium could be chelated by carboxyl oxygen and amino nitrogen atoms of collagen peptides, thus forming peptide-calcium chelate. The chelate was stable at various temperatures and pH values, and exhibited excellent stability in the gastrointestinal environment, which could promote calcium absorption in human gastrointestinal tract. Moreover, Caco-2 cell monolayer model was used to investigate the effect of peptide-calcium chelate on promoting calcium absorption. Results showed that peptide-calcium chelate could significantly improve calcium transport in Caco-2 cell monolayer and reverse the inhibition of calcium absorption by phosphate and phytate. The findings provide a scientific basis for developing new calcium supplements and the high-value utilization of pig bone.


Asunto(s)
Calcio/química , Colágeno/química , Porcinos , Animales , Huesos/química , Células CACO-2 , Humanos , Péptidos , Ácido Fítico , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
20.
Food Chem ; 275: 322-332, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30724203

RESUMEN

The potentialities of front-face fluorescence (FFF) and mid-infrared (MIR) spectroscopies coupled with partial least square regression (PLSR) were compared to predict the lipid oxidation of pound cakes. The level of lipid oxidation in pound cakes determined using classical methods showed some changes. Similarly, the fluorescence emission (305-490 nm) and excitation (252-390 nm) spectra and MIR spectra scanned in the 4000-700 cm-1 region showed some changes in pound cakes as a function of both storage time and the type of oil used in the formulation. The application of PLSR to the MIR spectra, provided excellent predictive results for free fatty acid (R2 = 0.97) and peroxide values (R2 = 0.87). Similar results were obtained from both tryptophan and MIR spectra for the prediction of TOTOX (R2 > 0.86) demonstrating the efficiency of the MIR and FFF spectroscopies to qualify and quantify the level of lipid oxidation in pound cakes.


Asunto(s)
Pan , Almacenamiento de Alimentos/métodos , Lípidos/química , Espectrometría de Fluorescencia/métodos , Espectrofotometría Infrarroja/métodos , Análisis de los Mínimos Cuadrados , Oxidación-Reducción , Aceite de Palma , Aceite de Brassica napus , Espectrometría de Fluorescencia/estadística & datos numéricos , Espectrofotometría Infrarroja/estadística & datos numéricos , Triptófano/química , Vitamina A/química
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