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1.
Fish Shellfish Immunol ; 129: 170-181, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36057429

RESUMEN

A meticulous understanding of the immune characteristics of aquaculture animals is the basis for developing precise disease prevention and control strategies. In this study, four novel C-type lectins (PtCTL-5, PtCTL-6, PtCTL-7 and PtCTL-8) including a single carbohydrate-recognition domain (CRD), and four novel crustins (Ptcrustin-1, Ptcrustin-2, Ptcrustin-3 and Ptcrustin-4) with a single whey acidic protein (WAP) domain were identified from the swimming crab Portunus trituberculatus. Tissue distribution analysis indicated that most of the target genes were predominantly expressed in the hepatopancreas in all examined tissues, except for Ptcrustin-1 which were mainly expressed in the gills. Our results showed that the eight genes displayed various transcriptional profiles across different tissues. In hemocytes, the PtCTL-7 responded quickly to Vibrio alginolyticus and exhibited much more strongly up-regulation than other three PtCTLs. The Ptcrustin-1 rapidly responded to V. alginolyticus within 3 h in all the three tested tissues. Furthermore, recombinant proteins of PtCTL-5 and PtCTL-8 were successfully obtained, and both of them displayed bacterial binding activities toward V. alginolyticus, V. harveyi and Staphylococcus aureus, and only showed antibacterial activity against V. harveyi. These findings provided new insights into the diverse immune response of P. trituberculatus and laid theoretical foundations for the development of precise disease prevention and control strategies in P. trituberculatus farming. Moreover, the specific anti-V. harveyi activities exhibited by rPtCTL-5 and rPtCTL-8 suggested their promising application prospects for controlling diseases caused by V. harveyi.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/inmunología , Braquiuros/inmunología , Lectinas Tipo C/fisiología , Secuencia de Aminoácidos , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Acuicultura , Proteínas de Artrópodos/química , Secuencia de Bases , Braquiuros/clasificación , Braquiuros/genética , Carbohidratos/aislamiento & purificación , Inmunidad Innata/genética , Lectinas Tipo C/química , Lectinas Tipo C/inmunología , Filogenia , Proteínas Recombinantes/genética , Alineación de Secuencia
2.
Molecules ; 26(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802601

RESUMEN

Annually, millions of tons of foods are generated with the purpose to feed the growing world population. One particular eatable is orange, the production of which in 2018 was 75.54 Mt. One way to valorize the orange residue is to produce bioethanol by fermenting the reducing sugars generated from orange peel. Hence, the objective of the present work was to determine the experimental conditions to obtain the maximum yield of reducing sugars from orange peel using a diluted acid hydrolysis process. A proximate and chemical analysis of the orange peel were conducted. For the hydrolysis, two factorial designs were prepared to measure the glucose and fructose concentration with the 3,5-DNS acid method and UV-Visible spectroscopy. The factors were acid concentration, temperature and hydrolysis time. After the hydrolysis, the orange peel samples were subjected to an elemental SEM-EDS analysis. The results for the orange peel were 73.530% of moisture, 99.261% of volatiles, 0.052% of ash, 0.687% of fixed carbon, 19.801% of lignin, 69.096% of cellulose and 9.015% of hemicellulose. The highest concentration of glucose and fructose were 24.585 and 9.709 g/L, respectively. The results highlight that sugar production is increased by decreasing the acid concentration.


Asunto(s)
Carbohidratos/química , Citrus sinensis/metabolismo , Residuos/análisis , Carbohidratos/aislamiento & purificación , Citrus sinensis/química , Fermentación , Hidrólisis , Temperatura
3.
Molecules ; 24(7)2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30979080

RESUMEN

Trichosanthes kirilowii Maxim. is one of the original plants for traditional Chinese medicines Trichosanthis Fructus, Trichosanthis Semen, Trichosanthis Pericarpium and Trichosanthis Radix. Amino acids, nucleosides and carbohydrates are usually considered to have nutritional value and health-care efficacy. In this study, methods involving high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD), UV-visible spectrophotometry and ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) were established for quantifying carbohydrates (fructose, glucose, stachyose, raffinose and polysaccharide), fourteen nucleosides and twenty one amino acids. Moreover, sixty-three samples from nine different parts, including pericarp, seed, fruit pulp, stem, leaf, main root, main root bark, lateral root and lateral root bark of T. kirilowii from different cultivated varieties were examined. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. The results showed that the average content of total amino acids in roots (15.39 mg/g) and root barks (16.38 mg/g) were relatively higher than for others. Contents of nucleosides in all parts of T. kirilowii were below 1.5 mg/g. For carbohydrates, fruit pulp has a higher content than others for glucose (22.91%), fructose (20.63%) and polysaccharides (27.29%). By using partial least-squared discriminate analysis (PLS-DA), Variable importance in the projection (VIP) plots and analysis of variance (ANOVA) analysis, the characteristic components of the different organs (fruit, stems and leaves, roots) were found. This analysis suggested there were potential medicinal and nutritive health care values in various parts of the T. kirilowii, which provided valuable information for the development and utilization of T. kirilowii.


Asunto(s)
Aminoácidos/química , Carbohidratos/química , Nucleósidos/química , Trichosanthes/química , Aminoácidos/aislamiento & purificación , Carbohidratos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Dispersión Dinámica de Luz , Frutas/química , Humanos , Medicina Tradicional China , Nucleósidos/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Semillas/química , Espectrometría de Masas en Tándem
4.
Molecules ; 24(18)2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31510066

RESUMEN

This study evaluated the effect of seasonal variation on the physicochemical, biochemical, and nutritional composition of Gracilaria manilaensis. Sampling was designed during the main monsoon seasons in Malaysia-the Southwest monsoon (SWM) and Northeast monsoon (NEM)-to understand the intraspecific variation (p < 0.05). Carbohydrates, protein, and dietary fiber were found to be higher in NEM-G. manilaensis, whereas a higher ash content was quantified in SWM-G. manilaensis. No significant differences were found in crude lipid and moisture content (p > 0.05). Vitamin B2 was calculated as (0.29 ± 0.06 mg 100 g-1) and (0.38 ± 0.06 mg 100 g-1) for the NEM and SWM samples, respectively (p < 0.05). The fatty acid profile showed the dominance of saturated fatty acids (SFAs)-palmitic acids, stearic acid, and myristic acid-while the mineral contents were found to be good sources of calcium (1750.97-4047.74 mg 100 g-1) and iron (1512.55-1346.05 mg 100 g-1). Tryptophan and lysine were recorded as the limiting essential amino acids (EAAs) in NEM G. manilaensis, while leucine and phenylalanine were found to be the limiting EAAs in the SWM samples. None of the extracts exhibited antibacterial properties against the screened strains. The study concluded that seasonal changes have a great effect on the biochemical composition of G. manilaensis.


Asunto(s)
Carbohidratos/química , Ácidos Grasos/química , Gracilaria/química , Valor Nutritivo , Carbohidratos/aislamiento & purificación , Fibras de la Dieta/análisis , Ácidos Grasos/aislamiento & purificación , Lípidos/química , Lípidos/aislamiento & purificación , Malasia , Minerales/química , Minerales/aislamiento & purificación , Extractos Vegetales/química , Proteínas/química , Proteínas/aislamiento & purificación , Estaciones del Año
5.
Molecules ; 24(12)2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31197120

RESUMEN

The present study sought to evaluate the nutritional composition and physicochemical properties of two dried commercially interesting edible red seaweeds, Gracilaria corticata and G. edulis. Proximate composition of the dried seaweeds revealed a higher content in carbohydrates (8.30 g/100 g), total crude protein (22.84 g/100 g) and lipid content (7.07 g/100 g) in G. corticata than in G. edulis. Fatty acids profile showed that G. corticata samples contain higher concentrations of saturated fatty acids, such as palmitic and stearic acids, and polyunsaturated ones such as α-linolenic and docosahexaenoic acids. Contrariwise, G. edulis contained higher amounts of monounsaturated oleic acid. Total amino acid content was 76.60 mg/g in G. corticata and 65.42 mg/g in G. edulis, being the essential amino acid content higher in G. edulis (35.55 mg/g) than in G. corticata (22.76 mg/g). Chlorophyll a was found in significantly higher amounts in G. edulis (17.14 µg/g) than G. corticata, whereas carotenoid content was significantly higher in G. corticata (12.98 µg/g) than in G. edulis. With respect to physical properties, both water- and oil-holding capacities were similar in both seaweeds, whereas swelling capacity was higher in G. edulis. In view of the results, the present study suggests that G. corticata and G. edulis contains important nutrients for human health and are possible natural functional foods.


Asunto(s)
Gracilaria/química , Micronutrientes/química , Valor Nutritivo , Algas Marinas/química , Aminoácidos/química , Aminoácidos/aislamiento & purificación , Carbohidratos/química , Carbohidratos/aislamiento & purificación , Carotenoides/química , Carotenoides/aislamiento & purificación , Clorofila A/química , Clorofila A/aislamiento & purificación , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Humanos , Micronutrientes/aislamiento & purificación , Oligoelementos/química
6.
Planta ; 247(5): 1077-1087, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29350280

RESUMEN

MAIN CONCLUSION: Six types of lignin-carbohydrate complex (LCC) fractions were isolated from Eucalyptus. The acidic dioxane treatment applied significantly improved the yield of LCCs. The extraction conditions had a limited impact on the LCC structures and linkages. Characterization of the lignin-carbohydrate complex (LCC) structures and linkages promises to offer insight on plant cell wall chemistry. In this case, Eucalyptus LCCs were extracted by aqueous dioxane, and then precipitated sequentially by 70% ethanol, 100% ethanol, and acidic water (pH = 2). The composition and structure of the six LCC fractions obtained by selective precipitation were investigated by sugar analysis, molecular weight determination, and 2D HSQC NMR. It was found that the acidic (0.05-M HCl) dioxane treatment significantly improved the yield of LCCs (66.4% based on Klason lignin), which was higher than the neutral aqueous dioxane extraction, and the extraction condition showed limited impact on the LCC structures and linkages. In the fractionation process, the low-molecular-weight LCCs containing a high content of carbohydrates (60.3-63.2%) were first precipitated by 70% ethanol from the extractable solution. The phenyl glycoside (PhGlc) bonds (13.0-17.0 per 100Ar) and highly acetylated xylans were observed in the fractions recovered by the precipitation with 100% ethanol. On the other hand, such xylan-rich LCCs exhibited the highest frequency of ß-O-4 linkages. The benzyl ether (BE) bonds were only detected in the fractions obtained by acidic water precipitation.


Asunto(s)
Carbohidratos/aislamiento & purificación , Eucalyptus/metabolismo , Lignina/aislamiento & purificación , Metabolismo de los Hidratos de Carbono , Carbohidratos/química , Precipitación Química , Dioxanos/uso terapéutico , Lignina/química , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Peso Molecular
7.
Mar Drugs ; 16(7)2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-29987239

RESUMEN

The oceans harbor a great diversity of organisms, and have been recognized as an important source of new compounds with nutritional and therapeutic potential. Among these compounds, carbohydrate-based compounds are of particular interest because they exhibit numerous biological functions associated with their chemical diversity. This gives rise to new substances for the development of bioactive products. Many are the known applications of substances with glycosidic domains obtained from marine species. This review covers the structural properties and the current findings on the antioxidant, anti-inflammatory, anticoagulant, antitumor and antimicrobial activities of medium and high molecular-weight carbohydrates or glycosylated compounds extracted from various marine organisms.


Asunto(s)
Organismos Acuáticos/química , Carbohidratos/farmacología , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Anticoagulantes/química , Anticoagulantes/aislamiento & purificación , Anticoagulantes/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Carbohidratos/química , Carbohidratos/aislamiento & purificación , Glicosilación , Estructura Molecular , Océanos y Mares , Relación Estructura-Actividad
8.
Molecules ; 23(6)2018 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-29861482

RESUMEN

A modified GC-MS analytical procedure based on trimethylsilyl-dithioacetal (TMSD) derivatization has been established for a simultaneous determination of thirteen carbohydrates. Different from previous approaches, the current GC-MS method was featured by a powerful practicability for simultaneous detection of aldoses, uronic acids, ketoses, and amino sugars; simplifying GC-MS chromatograms and producing a single peak for each derivatized sugar, as well as high resolution, sensitivity, and repeatability. An additional liquid-liquid extraction from derivatization mixtures was performed not only to increase the detection sensitivity of amino sugars but also to decrease the by-products of derivatization. Contrarily, three amino sugars were detected at a very low intensity or not detected at all. The effect of time on monosaccharide- mercaptalated reaction was systematically investigated. The effect of trimethylsilylation on the formation of TMSD was also optimized. The established GC-MS based on TMSD derivatization was suitable for complex carbohydrate analysis and has been successfully applied for the detection of free carbohydrates in water extracts of Anemarrhena asphodeloides roots and determination of monosaccharides in Glossy ganoderma polysaccharides.


Asunto(s)
Carbohidratos/análisis , Carbohidratos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Monosacáridos/análisis , Monosacáridos/aislamiento & purificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Biochemistry ; 56(17): 2247-2250, 2017 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-28418636

RESUMEN

Two protocols that allow for the comparison of Raman spectra of planktonic cells and biofilm formed from these cells in their growth phase have been developed. Planktonic cells are washed and flash-frozen in <1 min to reduce the time for metabolic changes during processing, prior to freeze-drying. Biofilm is formed by standing cells in 50 µL indentations in aluminum foil in an atmosphere of saturated water vapor for 24-48 h. The results for Escherichia coli type K12 cells, which do not readily form biofilm, are compared to those for Staphylococcus epidermidis cells, which prolifically synthesize biofilm. For E. coli, the Raman spectra of the planktonic and biofilm samples are similar with the exception that the spectral signature of RNA, present in planktonic cells, could not be detected in biofilm. For S. epidermidis, major changes occur upon biofilm formation. In addition to the absence of the RNA features, new bands occur near 950 cm-1 and between 1350 and 1420 cm-1 that are associated with an increase in carbohydrate content. Unlike the case in E. coli biofilm, the intensity of G base ring modes is reduced in but A and T base ring signatures become more prominent. For S. epidermis in the biofilm's amide III region, there is evidence of an increase in the level of ß-sheet structure accompanied by a decrease in α-helical content. The presence of biofilm is confirmed by microscope-aided photography and, separately, by staining with methyl violet.


Asunto(s)
Biopelículas , Escherichia coli K12/fisiología , Plancton/fisiología , Staphylococcus epidermidis/fisiología , Métodos Analíticos de la Preparación de la Muestra , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Carbohidratos/biosíntesis , Carbohidratos/aislamiento & purificación , Escherichia coli K12/química , Escherichia coli K12/citología , Escherichia coli K12/crecimiento & desarrollo , Liofilización , Microtecnología , Plancton/crecimiento & desarrollo , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , ARN Bacteriano/biosíntesis , ARN Bacteriano/aislamiento & purificación , Reproducibilidad de los Resultados , Espectrometría Raman , Staphylococcus epidermidis/química , Staphylococcus epidermidis/citología , Staphylococcus epidermidis/crecimiento & desarrollo
10.
Anal Biochem ; 527: 49-62, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28209457

RESUMEN

Thyme as a perennial herb has been recognized globally for its antimicrobial, antiseptic and spasmolytic effects. In this investigation, we have used non-targeted metabolite and volatile profiling combined with the morpho-physiological parameters in order to understand the responses at the metabolite and physiological level in drought sensitive and tolerant thyme plant populations. The results at the metabolic level identified the significantly affected metabolites. Significant metabolites belonging to different chemical classes consisting amino acids, carbohydrates, organic acids and lipids have been compared in tolerant and sensitive plants. These compounds may take a role through mechanisms including osmotic adjustment, ROS scavenging, cellular components protection and membrane lipid changes, hormone inductions in which the key metabolites were proline, betain, mannitol, sorbitol, ascorbate, jasmonate, unsaturated fatty acids and tocopherol. Regarding with volatile profiling, sensitive plants showed an increased-then-decreased trend at major terpenes apart from alpha-cubebene and germacrene-D. In contrast, tolerant populations had unchanged terpenes during the water stress period with an elevation at last day. These results suggesting that the two populations are employing different strategies. The combination of metabolite profiling and physiological parameters assisted to understand precisely the mechanisms of plant response at volatile metabolome level.


Asunto(s)
Adaptación Fisiológica , Sequías , Metaboloma , Hojas de la Planta/metabolismo , Thymus (Planta)/metabolismo , Aminoácidos/biosíntesis , Aminoácidos/aislamiento & purificación , Carbohidratos/biosíntesis , Carbohidratos/aislamiento & purificación , Ácidos Carboxílicos/aislamiento & purificación , Ácidos Carboxílicos/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Lípidos/biosíntesis , Lípidos/aislamiento & purificación , Metabolómica , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Análisis de Componente Principal , Estrés Fisiológico , Terpenos/aislamiento & purificación , Terpenos/metabolismo , Thymus (Planta)/química , Thymus (Planta)/crecimiento & desarrollo
11.
Faraday Discuss ; 206: 93-112, 2017 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-28936499

RESUMEN

Biomass based biofuels are already an important energy source, and will increasingly be so in the future as the need for renewable energy rises. Due to their fast multiplication rates, algae can provide a sustainable supply of biomass, and are attractive because they do not compete with food crops for habitat. Here we show that biomass derived from Chlorella vulgaris and Spirulina platensis can be pretreated with low cost choline amino acid based ionic liquids to effectively yield lipids (30.6% and 51% total lipids) and sugars (71% and 26% total sugars). The ionic liquids dissolve the lipids, leaving behind a carbohydrate rich solid. The lipids were extracted with hexane, and the solid was subjected to enzyme hydrolysis to release fermentable sugars. These results open new pathways towards the dual production of biodiesel and bioethanol from algae, using low cost ionic liquids.


Asunto(s)
Carbohidratos/aislamiento & purificación , Chlorella vulgaris/química , Líquidos Iónicos/química , Lípidos/aislamiento & purificación , Agua/química , Aminoácidos/química , Biomasa , Carbohidratos/química , Colina/química , Líquidos Iónicos/economía , Lípidos/química , Estructura Molecular , Spirulina/química
12.
An Acad Bras Cienc ; 89(3 Suppl): 2113-2117, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28876382

RESUMEN

Freshwater algae are rich sources of structurally biologically active metabolites, such as fatty acids, steroids, carotenoids and polysaccharides. Among these metabolites, lectins stand out. Lectins are proteins or glycoproteins of non-immune origin which bind to carbohydrates or glycoconjugates, without changing ligand structure. Many studies have reported on the use of Spirogyra spp. as effective bioindicators of heavy metals; however, reports on Spirogyra molecular bioprospecting are quite limited. Therefore, this study aimed to detect, isolate, purify and characterize a lectin present in the freshwater green algae Spirogyra. Presence of the lectin protein in the extract was detected by hemagglutination assays. Subsequently, the protein extract was subjected to a sugar inhibition assay to identify the lectin-specific carbohydrate. Following this, the extract was applied to a guar gum column to afford the pure lectin. The lectin was inhibited by N-acetyl-glucosamine and N-acetyl-beta-D-mannose, but more strongly by D-galactose. The apparent molecular mass of the purified lectin was evaluated by Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). Electrophoretic analysis revealed a single protein band with an apparent molecular mass of 56 kDa. Thus, it could be concluded that a lectin was purified from Spirogyra spp.


Asunto(s)
Lectinas de Plantas/aislamiento & purificación , Spirogyra/química , Carbohidratos/clasificación , Carbohidratos/aislamiento & purificación , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Agua Dulce , Pruebas de Hemaglutinación , Lectinas de Plantas/química
13.
Molecules ; 22(12)2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-29261155

RESUMEN

The quality control of Polygala tenuifolia Wild. is a major challenge in its clinical application. In this paper, a new strategy for the quality evaluation of P. tenuifolia extracts was verified through reverse-phase ultra-performance liquid chromatography (UPLC). The quantitative analysis of multi-components by a single marker (QAMS) was conducted with 3,6'-disinapoyl sucrose as an internal reference substance. Eight components (i.e., sibiricose A5, sibiricose A6, glomeratose A, tenuifoliside A, tenuifoliside B, tenuifoliside C, sibiricaxanthone B, and polygalaxanthone III) were determined based on the relative correction factors. The concentrations of these components were also determined by applying a conventional external standard method. The cosine value confirmed the consistency of the two methods (cosine ratio value >0.999920). Hierarchical cluster analysis, radar plots, and discriminant analysis were performed to classify 23 batches of P. tenuifolia extracts from Shanxi, Hebei, and Shaanxi in China. Results revealed that QAMS combined with radar plots and multivariate data analysis could accurately measure and clearly distinguish the different quality samples of P. tenuifolia. Hence, QAMS is a feasible and promising method for the quality control of P. tenuifolia.


Asunto(s)
Carbohidratos/análisis , Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Extractos Vegetales/análisis , Polygala/química , Carbohidratos/química , Carbohidratos/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Control de Calidad
14.
Zhongguo Zhong Yao Za Zhi ; 42(19): 3666-3671, 2017 Oct.
Artículo en Zh | MEDLINE | ID: mdl-29235277

RESUMEN

This study aims to investigate the targets and targets-involved mechanism for the macrophage activation of low molecular weight saccharides from Cistanche deserticola (LMSC). The phagocytic activity and NO release of RAW264.7 cells were detected, and results showed that LMSC exerts immune activation effect by significantly increasing the phagocytic activity and NO release. LMSC-conjugated epoxy-activated sepharose beads were prepared as affinity reagent to capture the target proteins. Twenty-four proteins such as Eef2 were identified by LC-MS/MS analysis. Pathway enrichment analysis showed LMSC activated RAW264.7 cells by regulating Fcgamma receptor dependent phagocytosis, TNF-alpha NF-κB signaling pathway, glycolysis/gluconeogenesis and the citric acid cycle and respiratory electron transport pathway.


Asunto(s)
Carbohidratos/farmacología , Cistanche/química , Activación de Macrófagos/efectos de los fármacos , Animales , Carbohidratos/aislamiento & purificación , Cromatografía de Afinidad , Cromatografía Liquida , Ratones , Peso Molecular , Óxido Nítrico/metabolismo , Fagocitosis , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Células RAW 264.7 , Transducción de Señal , Espectrometría de Masas en Tándem
15.
Planta ; 243(5): 1143-58, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26848983

RESUMEN

MAIN CONCLUSION: Two types of lignins occurred in different lignin-carbohydrate fractions, a lignin enriched in syringyl units, less condensed, preferentially associated with xylans, and a lignin with more guaiacyl units, more condensed, associated with glucans. Lignin-carbohydrate complexes (LCC) were isolated from the fibers of sisal (Agave sisalana) and abaca (Musa textilis) according to a plant biomass fractionation procedure recently developed and which was termed as "universally" applicable to any type of lignocellulosic material. Two LCC fractions, namely glucan-lignin (GL) and xylan-lignin (XL), were isolated and differed in the content and composition of carbohydrates and lignin. In both cases, GL fractions were enriched in glucans and comparatively depleted in lignin, whereas XL fractions were depleted in glucans, but enriched in xylans and lignin. Analysis by two-dimensional Nuclear Magnetic Resonance (2D-NMR) and Derivatization Followed by Reductive Cleavage (DFRC) indicated that the XL fractions were enriched in syringyl (S)-lignin units and ß-O-4' alkyl-aryl ether linkages, whereas GL fractions have more guaiacyl (G)-lignin units and less ß-O-4' alkyl-aryl ether linkages per lignin unit. The data suggest that the structural characteristics of the lignin polymers are not homogeneously distributed within the same plant and that two different lignin polymers with different composition and structure might be present. The analyses also suggested that acetates from hemicelluloses and the acyl groups (acetates and p-coumarates) attached to the γ-OH of the lignin side chains were extensively hydrolyzed and removed during the LCC fractionation process. Therefore, caution must be paid when using this fractionation approach for the structural characterization of plants with acylated hemicelluloses and lignins. Finally, several chemical linkages (phenylglycosides and benzyl ethers) could be observed to occur between lignin and xylans in these plants.


Asunto(s)
Agave/química , Carbohidratos/química , Lignina/química , Musa/química , Conformación de Carbohidratos , Carbohidratos/aislamiento & purificación , Fraccionamiento Químico , Glucanos/química , Glucanos/aislamiento & purificación , Lignina/aislamiento & purificación , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Madera/química , Xilanos/química , Xilanos/aislamiento & purificación
16.
Biotechnol Bioeng ; 113(2): 320-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26222672

RESUMEN

Biofuels derived from microalgae have promise as carbon-neutral replacements for petroleum. However, difficulty extracting microalgae-derived lipids and the co-extraction of non-lipid components add major costs that detract from the benefits of microalgae-based biofuel. Selective fermentation could alleviate these problems by managing microbial degradation so that carbohydrates and proteins are hydrolyzed and fermented, but lipids remain intact. We evaluated selective fermentation of Scenedesmus biomass in batch experiments buffered at pH 5.5, 7, or 9. Carbohydrates were fermented up to 45% within the first 6 days, protein fermentation followed after about 20 days, and lipids (measured as fatty acid methyl esters, FAME) were conserved. Fermentation of the non-lipid components generated volatile fatty acids, with acetate, butyrate, and propionate being the dominant products. Selective fermentation of Scenedesmus biomass increased the amount of extractable FAME and the ratio of FAME to crude lipids. It also led to biohydrogenation of unsaturated FAME to more desirable saturated FAME (especially to C16:0 and C18:0), and the degree of saturation was inversely related to the accumulation of hydrogen gas after fermentation. Moreover, the microbial communities after selective fermentation were enriched in bacteria from families known to perform biohydrogenation, i.e., Porphyromonadaceae and Ruminococcaceae. Thus, this study provides proof-of-concept that selective fermentation can improve the quantity and quality of lipids that can be extracted from Scenedesmus.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Carbohidratos/aislamiento & purificación , Ácidos Grasos/aislamiento & purificación , Proteínas/aislamiento & purificación , Proteínas/metabolismo , Scenedesmus/química , Fermentación , Concentración de Iones de Hidrógeno , Scenedesmus/metabolismo , Factores de Tiempo
17.
Anal Bioanal Chem ; 408(23): 6369-79, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27423193

RESUMEN

The aim of the present study was to optimize a protocol for extracting extracellular polymeric substances (EPS) from biofilms on rocky substrata, as the EPS matrix is considered key to understanding the biofilm mode of life. For this purpose, we tested the extraction efficacy of NaOH and H2SO4 at different concentrations, temperatures and times for obtaining EPS from multi-species subaerial biofilms grown on granite blocks under laboratory conditions. Two experimental designs (Box-Behnken design and full factorial design) were used in testing each extractant. The extraction efficiency was determined by analysing the carbohydrate, protein and DNA contents of the extracts obtained. H2SO4 proved unsuitable as an extractant as it caused excessive cell lysis. However, response surface optimization of NaOH-mediated extraction enabled cell lysis to be minimized. Confirmation experiments were performed under the optimal conditions established and a protocol for extracting EPS is proposed, yielding the first quantitative data on EPS extracted from subaerial biofilms developed on rocky substrata. Graphical abstract Development of a method for extracting EPS from subaerial biofilms on rocky substrata.


Asunto(s)
Biopelículas , Carbohidratos/aislamiento & purificación , Fraccionamiento Químico/métodos , Chlorophyta/química , Cianobacterias/química , ADN/aislamiento & purificación , Proteínas/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Chlorophyta/fisiología , Cianobacterias/fisiología , Sedimentos Geológicos/microbiología , Polímeros/aislamiento & purificación , Dióxido de Silicio/química
18.
Appl Microbiol Biotechnol ; 100(22): 9439-9450, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27687993

RESUMEN

Brown macroalgae are renewable and sustainable biomass resources for the production of biofuels and chemicals, owing to their high levels of carbohydrates and low levels of lignin. To increase the biological usage of brown macroalgae, it is necessary to depolymerize the polysaccharides that generate macroalgal monomeric sugars or sugar derivatives and to convert them into fermentable sugars for the production of biofuels and chemicals. In this review, we discuss the chemical and enzymatic saccharification of the major carbohydrates found in brown macroalgae and the use of the resulting constituents in the production of biofuels and chemicals, as well as high-value health-benefiting functional oligosaccharides and sugars. We also discuss recently reported experimental results, novel enzymes, and technological breakthroughs that are related to polysaccharide depolymerization, fermentable sugar production, and the biological conversion of non-favorable sugars for fermentation using industrial microorganisms. This review provides a comprehensive perspective of the efficient utilization of brown macroalgae as renewable resources for the production of biofuels and chemicals.


Asunto(s)
Biomasa , Metabolismo de los Hidratos de Carbono , Carbohidratos/aislamiento & purificación , Algas Marinas/química , Biotransformación , Fermentación
19.
J Exp Bot ; 66(11): 3085-97, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25821071

RESUMEN

Root parasitic weeds in Orobanchaceae cause serious damage to worldwide agriculture. Germination of the parasites requires host-derived germination stimulants, such as strigolactones, as indicators of host roots within reach of the parasite's radicles. This unique germination process was focused on to identify metabolic pathways required for germination, and to design a selective control strategy. A metabolomic analysis of germinating seeds of clover broomrape, Orobanche minor, was conducted to identify its distinctive metabolites. Consequently, a galactosyl-sucrose trisaccharide, planteose (α-d-galactopyranosyl-(1→6)-ß-d-fructofuranosyl-(2→1)-α-d-glucopyranoside), was identified as a metabolite that decreased promptly after reception of the germination stimulant. To investigate the importance of planteose metabolism, the effects of several glycosidase inhibitors were examined, and nojirimycin bisulfite (NJ) was found to alter the sugar metabolism and to selectively inhibit the germination of O. minor. Planteose consumption was similar in NJ-treated seeds and non-treated germinating seeds; however, NJ-treated seeds showed lower consumption of sucrose, a possible intermediate of planteose metabolism, resulting in significantly less glucose and fructose. This inhibitory effect was recovered by adding glucose. These results suggest that planteose is a storage carbohydrate required for early stage of germination of O. minor, and NJ inhibits germination by blocking the supply of essential glucose from planteose and sucrose. Additionally, NJ selectively inhibited radicle elongation of germinated seeds of Orobanchaceae plants (Striga hermonthica and Phtheirospermum japonicum). Thus, NJ will be a promising tool to develop specific herbicides to the parasites, especially broomrapes, and to improve our understanding of the molecular mechanisms of this unique germination.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Orobanchaceae/parasitología , Orobanche/metabolismo , Enfermedades de las Plantas/parasitología , Carbohidratos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Germinación , Metabolómica , Orobanche/crecimiento & desarrollo , Raíces de Plantas/parasitología , Malezas , Semillas/crecimiento & desarrollo , Semillas/metabolismo
20.
Biotechnol Bioeng ; 112(11): 2324-33, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25943383

RESUMEN

Conversion of biomass feedstock to chemicals and fuels has attracted increasing attention recently. Soybean meal, containing significant quantities of carbohydrates, is an inexpensive renewable feedstock. Glucose, galactose, and fructose can be obtained by enzymatic hydrolysis of soluble carbohydrates of soybean meal. Free fatty acids (FFAs) are valuable molecules that can be used as precursors for the production of fuels and other value-added chemicals. In this study, free fatty acids were produced by mutant Escherichia coli strains with plasmid pXZ18Z (carrying acyl-ACP thioesterase (TE) and (3R)-hydroxyacyl-ACP dehydratase) using individual sugars, sugar mixtures, and enzymatic hydrolyzed soybean meal extract. For individual sugar fermentations, strain ML211 (MG1655 fadD(-) fabR(-) )/pXZ18Z showed the best performance, which produced 4.22, 3.79, 3.49 g/L free fatty acids on glucose, fructose, and galactose, respectively. While the strain ML211/pXZ18Z performed the best with individual sugars, however, for sugar mixture fermentation, the triple mutant strain XZK211 (MG1655 fadD(-) fabR(-) ptsG(-) )/pXZ18Z with an additional deletion of ptsG encoding the glucose-specific transporter, functioned the best due to relieved catabolite repression. This strain produced approximately 3.18 g/L of fatty acids with a yield of 0.22 g fatty acids/g total sugar. Maximum free fatty acids production of 2.78 g/L with a high yield of 0.21 g/g was achieved using soybean meal extract hydrolysate. The results suggested that soybean meal carbohydrates after enzymatic treatment could serve as an inexpensive feedstock for the efficient production of free fatty acids.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Carbohidratos/aislamiento & purificación , Escherichia coli/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Glycine max/química , Ingeniería Metabólica/métodos , Biotransformación , Redes y Vías Metabólicas/genética , Plásmidos
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