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1.
Molecules ; 24(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510066

RESUMO

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.


Assuntos
Carboidratos/química , Ácidos Graxos/química , Gracilaria/química , Valor Nutritivo , Carboidratos/isolamento & purificação , Fibras na Dieta/análise , Ácidos Graxos/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Malásia , Minerais/química , Minerais/isolamento & purificação , Extratos Vegetais/química , Proteínas/química , Proteínas/isolamento & purificação , Estações do Ano
2.
Molecules ; 24(12)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31197120

RESUMO

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.


Assuntos
Gracilaria/química , Micronutrientes/química , Valor Nutritivo , Alga Marinha/química , Aminoácidos/química , Aminoácidos/isolamento & purificação , Carboidratos/química , Carboidratos/isolamento & purificação , Carotenoides/química , Carotenoides/isolamento & purificação , Clorofila A/química , Clorofila A/isolamento & purificação , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Humanos , Micronutrientes/isolamento & purificação , Oligoelementos/química
3.
J Biosci Bioeng ; 128(3): 296-301, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30962100

RESUMO

Soybean meal has been intensively used as a substrate in culture media for several microorganisms. However, the fermentable sugar containing the soybean needs to be released from the solid matrix through different processes. Against this backdrop, the present study explores the use of high-energy ball milling as a one-step treatment method for expedited production of fermentable sugars of textured soybean. The best result is observed after only 5 min of milling, obtaining 34.1 times more fermentable sugars than untreated textured soybean, and 2.5 times more than commercially used soybean meal. Notably, the textured soybean ball-milled has been used as a substrate for Bacillus thuringiensis var. kurstaki HD-73 fermentation. The cell and spore production is also compared with a standard Rowe media. The maximum cell concentration obtained in the entire fermentation process using ball-milled textured soybean media is found to be higher than the concentration obtained using the standard Rowe media. In addition, it is observed that there is a direct correlation between maximum cell production and reducing sugar concentration generated by the high-energy ball milling treatment. No fermentation inhibitors or by-products are generated during the physical treatment.


Assuntos
Bacillus thuringiensis/citologia , Biomassa , Fracionamento Químico/métodos , Meios de Cultura/química , Técnicas Microbiológicas/métodos , Soja/química , Açúcares/isolamento & purificação , Carboidratos/isolamento & purificação , Fermentação , Ondas de Choque de Alta Energia , Açúcares/química
4.
Molecules ; 24(7)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30979080

RESUMO

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.


Assuntos
Aminoácidos/química , Carboidratos/química , Nucleosídeos/química , Trichosanthes/química , Aminoácidos/isolamento & purificação , Carboidratos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Difusão Dinâmica da Luz , Frutas/química , Humanos , Medicina Tradicional Chinesa , Nucleosídeos/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Raízes de Plantas/química , Sementes/química , Espectrometria de Massas em Tandem
5.
Food Funct ; 10(5): 2278-2289, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-30968919

RESUMO

Marine molluscs and their bioactive compounds are of particular relevance to the growing pool of nutraceutical resources under global investigation. A number of extraction techniques have been developed to isolate bioactive compounds according to their chemical characterization, such as proteins, carbohydrates and lipids. We briefly reviewed those methods in general. Bioactive molecules are 'concealed' in the primary structures of tissue samples of molluscs as amino acids, lipids or carbohydrates which are released by mechanical and chemical processes. The major health benefits of extracts of molluscs include antioxidant, anticancer, and anti-infectious disease activities and cardiovascular protection, which have been reviewed in detail. This review provides a novel view into the efficacy of isolation techniques and subsequent bioactivity analysis of compounds under investigation. Future development in extraction-bioactivity has also been discussed.


Assuntos
Carboidratos/isolamento & purificação , Análise de Alimentos/métodos , Lipídeos/isolamento & purificação , Moluscos/química , Proteínas/isolamento & purificação , Frutos do Mar/análise , Animais , Carboidratos/química , Lipídeos/química , Proteínas/química
6.
Int J Biol Macromol ; 123: 201-209, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30439423

RESUMO

In this study, three-phase partitioning (TPP) was used to directly extract and separate bioactive exopolysaccharides (EPSs) from a cultured broth of Phellinus baumii. The maximum extraction yield of EPS was 52.09% under the following optimal conditions: 20% (w/v) ammonium sulfate concentration, 1.0:1.5 (v/v) ratio of cultured broth to t­butanol, 30 min, and 35 °C. A multifrequency power ultrasound in a sequential mode coupled with TPP resulted in ~9.12% increment in extraction yield and ~80% reduction in extraction time compared with those of traditional TPP. The carbohydrate (88.21%) and uronic acid (3.37%) contents of partially purified EPS were higher than those of EPS-C obtained through conventional ethanol precipitation and separation methods. EPS and EPS-C exhibited similar preliminary structural characteristics and different monosaccharide compositions and molecular weights. The radical-scavenging abilities, antioxidant capacities, α­amylase and α­glycosidase inhibitory activities, and macrophage stimulation activities of EPS were also higher than those of EPS-C. Therefore, it could be concluded that TPP as a simple and green separation technique could be used to directly extract and separate bioactive EPS from the fermentation broths of mushrooms and other fungi.


Assuntos
Antioxidantes/isolamento & purificação , Carboidratos/isolamento & purificação , Polissacarídeos/isolamento & purificação , Sulfato de Amônio/química , Antioxidantes/química , Antioxidantes/farmacologia , Basidiomycota/química , Carboidratos/química , Carboidratos/farmacologia , Fermentação , Macrófagos/efeitos dos fármacos , Peso Molecular , Polissacarídeos/química , Polissacarídeos/farmacologia , Ácidos Urônicos/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/efeitos dos fármacos
7.
Int J Biol Macromol ; 126: 376-384, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30593808

RESUMO

Isolation of earth abundant biopolymer, Lignin, from Dendrocalamus sinicus and their structural properties were investigated to achieve its large-scale practical applications in value-added products. Two lignin fractions (MWL, DSL) were isolated with successive treatments of dioxane and dimethylsulfoxide (DMSO) from dewaxed and ball milled bamboo (D. sinicus) sample. The two-step treatments yielded 52.1% lignin based on the total lignin content in the dewaxed bamboo sample. Spectroscopy analyses indicated that the isolated bamboo lignin was a typical grass lignin, consisting of p-hydroxyphenyl, guaiacyl, and syringyl units. The major interunit linkages presented in the obtained bamboo lignin were ß-O-4' aryl ether linkages, together with lower amounts of ß-ß', ß-5', and ß-1' linkages. The tricin was detected to be linked to lignin polymer through the ß-O-4' linkage in the bamboo. In addition, phenyl glycoside and benzyl ether lignin-carbohydrate complexes (LCC) linkages were clearly detected in bamboo (D. sinicus), whereas the γ-ester LCC linkages were ambiguous due to the overlapping NMR signals with other substructures. The detailed structural properties of the obtained lignin fraction together with the light-weight will benefit efficient utilization of natural polymers as a possibly large-scale bio-based precursor for making polymeric materials, biochemicals, functional carbon and biofuels, and multifunctional polymer nanocomposites.


Assuntos
Carboidratos/isolamento & purificação , Lignina/química , Poaceae/química , Carboidratos/química , Espectroscopia de Ressonância Magnética , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Food Chem ; 266: 146-154, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30381169

RESUMO

Due to the great interest in obtaining natural bioactive carbohydrates to be used as functional ingredients, a selective microwave assisted extraction (MAE) method was optimized to ensure the exhaustive extraction of inositols and α-galactooligosaccharides (α-GOS) from mung bean. Thereafter, a comprehensive characterization of these compounds was carried out by gas chromatography coupled to mass spectrometry (GC-MS). Apart from free inositols and α-GOS, several glycosyl-methyl-scyllo-inositols and glycosyl-inositols were detected for the first time in this legume. Under optimized MAE conditions (0.5 g dry sample, 2 cycles of 3 min, 50 °C, 10 mL 50:50 ethanol:water, v:v), bioactive carbohydrates yields were similar to those found using solid-liquid extraction (SLE), but with shorter analytical times. Concentrations of bioactive carbohydrates in MAE extracts from samples of different geographical origins ranged between 74.1 and 104.2 mg.g-1 dry sample. MAE was proved a good alternative to SLE to obtain extracts enriched in bioactive carbohydrates.


Assuntos
Carboidratos/análise , Vigna/metabolismo , Carboidratos/isolamento & purificação , Fabaceae/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Inositol/análise , Inositol/isolamento & purificação , Micro-Ondas , Peso Molecular , Oligossacarídeos/análise , Oligossacarídeos/isolamento & purificação , Extratos Vegetais/metabolismo
9.
Fitoterapia ; 131: 23-34, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30304706

RESUMO

In this work, new biotechnological procedures have been optimized on the basis of immobilization in alginate of bionts isolated from the lichen C. substellata. From these immobilizates, soluble and biologically active phenolics can be obtained. During bionts-immobilization, stictic, norstictic and usnic acids were secreted to the medium. The amount produced of each of them differed depending on the immobilization time, the precursor supplied and the type of biont used. Greater amounts of stictic acid were detected and maintained over time in all bioreactors. The opposite occurs in non-immobilized thallus. Virtually, all lichen phenols exhibit antioxidant activity to a greater or lesser degree, so that the antioxidant capacity of stictic acid (82.13% oxidation inhibition) was tested. The soluble extract of immobilized algae co-incubated in sodium acetate with fungal hyphae contained carbohydrates and exhibited a potent antioxidant capacity after 13 days of immobilization (94.87%). Therefore, attempts have been made to relate both parameters. On the other hand, the growth of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae was inhibited by phenolic compounds produced by immobilizates, although the organic extract of the whole lichen showed the highest activity due to a possible synergy with other indeterminate compounds. Thus, C. substellata immobilized bionts are a potential source of different natural antioxidant and antimicrobial compounds.


Assuntos
Antioxidantes/isolamento & purificação , Clorófitas/química , Líquens/microbiologia , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Carboidratos/isolamento & purificação , Células Imobilizadas , Fungos/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia
10.
J Chromatogr A ; 1570: 116-125, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30098734

RESUMO

An extensive characterization of low molecular weight carbohydrates (LMWC) and phenylalkanoid glycosides (PAG) of Sedum roseum root supplements has been carried out for the first time by gas chromatography coupled to mass spectrometry (GC-MS) and by comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-ToF MS). Optimization of the required derivatization procedure for improved determination of PAG showed the combined use of trimethylsilylimidazole and trimethylchlorosilane as the most appropriate reagents. Up to 37 compounds were qualitative- and quantitatively characterized in different dietary supplements of S. roseum by GC-MS. In addition to the well-known rosin, rosarin, rosavin and salidroside, other carbohydrates, polyalcohols, acids, etc. were determined. Among them, several seven-carbon monosaccharides such as coriose and 2,7-anhydro-ß-d-altro-heptulose were detected for the first time in S. roseum root supplements. Sedoheptulose was found to be the most abundant compound (9-151 mg g-1), followed by rosiridin (20-81 mg g-1) and rosavin (11-56 mg g-1). The use of GC × GC-ToF MS allowed the detection and tentative assignation of 48 additional compounds mainly belonging to the phenylalkanoid glycoside, pentosyl-hexose and hexosyl-hexose families.


Assuntos
Carboidratos/análise , Suplementos Nutricionais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicosídeos/análise , Raízes de Plantas/química , Sedum/química , Carboidratos/química , Carboidratos/isolamento & purificação , Glicosídeos/química , Glicosídeos/isolamento & purificação , Peso Molecular
11.
FEMS Microbiol Ecol ; 94(9)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010859

RESUMO

Several species of Trichoderma promote plant growth and help in defense against root pathogens. The role of root-exuded carbohydrates as chemo-attractive stimuli for Trichoderma colonization is attracting considerable interest. In this project, we studied the interaction between Trichoderma atroviride and tomato (Lycopersicon esculentum L. cv. Río Grande) plants in two different stages, before and during root colonization. In addition, the biocontrol capacity of T. atroviride against the phytopathogen Phytophthora cinnamomi in a tripartite interaction system was examined. We found that the beneficial effects of T. atroviride on plant growth were fine-tuned depending on the progress of interaction. Interestingly, the composition of the carbohydrate exudate from plants interacting with T. atroviride was different from that produced by other treatments and probably provided a nutritional source for the fungus. Particularly, sucrose was found only during root colonization by the fungus. Our data show that root-derived sugars enabled a higher Trichoderma growth rate, and that, in the tripartite interaction system with P. cinnamomi, the fungus competes for space and available soil nutrients more efficiently than P. cinnamomi, thereby antagonizing the growth of the phytopathogen.


Assuntos
Agentes de Controle Biológico/metabolismo , Carboidratos/isolamento & purificação , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/parasitologia , Phytophthora/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Doenças das Plantas/parasitologia , Raízes de Plantas/metabolismo , Trichoderma/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Raízes de Plantas/parasitologia , Sacarose/metabolismo , Trichoderma/metabolismo
12.
J Chromatogr A ; 1567: 147-154, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-29983168

RESUMO

The effects of co-eluents and additives on separation and signal-to-noise ratio in analyses of monosaccharides by graphitised carbon chromatography (GCC) in combination with charged aerosol detection were studied. Design of experiments was used to model and predict the elution of two monosaccharide isomers, galactose and glucose and the corresponding amine at varying isocratic conditions, including concentration of water-soluble co-eluent, flow and temperature. The study confirmed the well-known order of eluent strength of the co-eluents investigated but showed that the eluent strength of MeOH was significantly lower than that of ACN, and at co-eluent concentrations ≥5% (v/v) IPA approached that of THF. Addition of NH3 increased retention and improved both peak shape and separation but the detector response decreased with increasing NH3 concentration lowering the signal-to-noise ratio. The best combination of response, retention and separation was obtained at 0.1% NH3. Increasing column temperature in the range of 15-50°C resulted in decreased retention times and resolution. The corresponding Van't Hoff correlations showed negative adsorption enthalpies indicating an exothermic adsorption process driven by a decrease in entropy minimising the surface energy of the system. Isocratic elution with MeOH as co-eluent offered limited possibilities for optimisation of resolution due to the opposite effects of changes in co-eluent concentration and changes in flow rate. Elution with acetonitrile as co-eluent showed possibilities for optimisation of the resolution within the range of flow rates of 0.6-0.95mL/min and co-eluent concentrations of 0.1-0.3%, with the highest resolution predicted at 0.1% acetonitrile and a flow rate of 0.81mL/min. Saccharides in the size range DP1-4, including amino, acetamido, and deoxy sugars, were separated using a binary gradient method. Higher retention was observed for increasing degree of polymerisation (DP) and N-acetylated saccharides were retained longer than non-substituted saccharides of corresponding DP. Partial resolution of two lacto-N-tetrasaccharide positional isomers was obtained.


Assuntos
Aerossóis/análise , Carboidratos/análise , Carboidratos/química , Cromatografia Líquida de Alta Pressão/métodos , Grafite/química , Razão Sinal-Ruído , Acetonitrilos/química , Aerossóis/química , Análise de Variância , Carboidratos/isolamento & purificação , Glucose/análise , Isomerismo , Metanol/química , Solventes/química , Termodinâmica
13.
Mar Drugs ; 16(7)2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29987239

RESUMO

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.


Assuntos
Organismos Aquáticos/química , Carboidratos/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Carboidratos/química , Carboidratos/isolamento & purificação , Glicosilação , Estrutura Molecular , Oceanos e Mares , Relação Estrutura-Atividade
14.
Molecules ; 23(6)2018 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-29861482

RESUMO

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.


Assuntos
Carboidratos/análise , Carboidratos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Monossacarídeos/análise , Monossacarídeos/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Food Res Int ; 109: 455-471, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29803472

RESUMO

The aim of this work was to produce an extract rich in different bioactive compounds from Arbutus unedo L. fruits to enhance its possible valorization and commercialization. The conditions of the main variables of maceration, microwave, and ultrasound assisted extractions (MA, MAE and UAE, respectively) were optimized and compared in terms of its composition (based on the total material extracted, total content in carbohydrates, phenolic and flavonoid compounds) and its preservative potential (based on the response of four in vitro antioxidant assays). The key variables of each extraction technique (time, temperature or power and hydroalcoholic mixture) were evaluated by specific experimental designs using response surface methodology. Mathematical models were developed and numerical optimal values for each extraction technique and response were achieved. Regarding the extraction of target compositional compounds, MAE was the most efficient, closely followed by MA. In terms of its preservative potential, MAE was the most suitable solution, but MA gave similar results at lower temperatures (~90 °C). Globally, MA and MAE were the best options conducting to optimal solutions using reduced amounts of ethanol. UAE required higher ethanol contents (~60%). The results showed alternatives to obtain extracts of A. unedo fruits, supporting their potential to be exploited at industrial level.


Assuntos
Ericaceae/química , Manipulação de Alimentos/métodos , Frutas/química , Micro-Ondas , Compostos Fitoquímicos/isolamento & purificação , Ultrassom , Carboidratos/isolamento & purificação , Simulação por Computador , Flavonoides/isolamento & purificação , Modelos Teóricos , Fenóis/isolamento & purificação , Solventes/química , Temperatura Ambiente , Fatores de Tempo
16.
Food Chem ; 258: 284-294, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29655735

RESUMO

Fifty-six cocoa bean samples from different origins and status of fermentation were analyzed by a validated hydrophilic interaction liquid chromatography-electrospray ionization-time of flight-mass spectrometry (HILIC-ESI-TOF-MS) method. The profile of the low molecular weight carbohydrate (LMWC) was analyzed by high resolution and tandem mass spectrometry, which allowed the identification of mono-, di-, tri- and tetrasaccharides, sugar alcohols and iminosugars. This study provides, for the first time in a large set of samples, a comprehensive absolute quantitative data set for the carbohydrates identified in cocoa beans (fructose, glucose, mannitol, myo-inositol, sucrose, melibiose, raffinose and stachyose). Differences in the content of carbohydrates were observed between unfermented (range of 0.9-4.9 g/g DM) and fermented (range 0.1-0.5 g/g DM) cocoa beans. The use of multivariate statistical tools allowed the identification of biomarkers suitable for cocoa bean classification according to the status of fermentation, procedure of fermentation employed and number of days of fermentation.


Assuntos
Cacau/metabolismo , Carboidratos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas por Ionização por Electrospray , Cacau/química , Carboidratos/isolamento & purificação , Análise Discriminante , Interações Hidrofóbicas e Hidrofílicas , Análise dos Mínimos Quadrados , Limite de Detecção , Peso Molecular , Monossacarídeos/análise , Monossacarídeos/isolamento & purificação , Análise de Componente Principal , Extração em Fase Sólida
17.
Int J Biol Macromol ; 111: 1238-1244, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29337104

RESUMO

Marine seaweeds contain a valuable source of functional bioactive polysaccharide and it plays main role for effective anticancer activity. The structural feature of SPs was studied through FT-IR and 1H NMR spectra analysis. The isolated SPs from A. spicifera contain 63.3% of total sugar, 21.9% of total sulfate and 12.6% of total uranic acid was found. The active F2 fraction molecular weight of SP was found to be 420 kDa. The sugar was composed of galactose (73.5%), xylose (9.2%), mannose (1.9%) and arabinose (10.9%). Further the SP showed DPPH free radical scavenging activity of 55.55% at 150 µg/mL and reducing power activity of 91.3% at 125 µg/mL. In the present study, the purified sulfated polysaccharide (fraction F2) were extracted, purified and characterized for red seaweed and evaluated for their potential anticancer activity of in A549 cell lines under in vitro condition. These polysaccharide fractions exhibited potential apoptotic effects on A549 cell lines.


Assuntos
Antioxidantes/química , Depuradores de Radicais Livres/química , Polissacarídeos/química , Rodófitas/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Compostos de Bifenilo/isolamento & purificação , Carboidratos/química , Carboidratos/isolamento & purificação , Depuradores de Radicais Livres/isolamento & purificação , Galactose/química , Galactose/isolamento & purificação , Peso Molecular , Polissacarídeos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química , Xilose/química
18.
Planta ; 247(5): 1077-1087, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29350280

RESUMO

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.


Assuntos
Carboidratos/isolamento & purificação , Eucalyptus/metabolismo , Lignina/isolamento & purificação , Metabolismo dos Carboidratos , Carboidratos/química , Precipitação Química , Dioxanos/uso terapêutico , Lignina/química , Lignina/metabolismo , Espectroscopia de Ressonância Magnética , Peso Molecular
19.
Trends Biotechnol ; 36(2): 216-227, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29132753

RESUMO

Although microalgae are a promising biobased feedstock, industrial scale production is still far off. To enhance the economic viability of large-scale microalgae processes, all biomass components need to be valorized, requiring a multi-product biorefinery. However, this concept is still too expensive. Typically, downstream processing of industrial biotechnological bulk products accounts for 20-40% of the total production costs, while for a microalgae multi-product biorefinery the costs are substantially higher (50-60%). These costs are high due to the lack of appropriate and mild technologies to access the different product fractions such as proteins, carbohydrates, and lipids. To reduce the costs, simplified processes need to be developed for the main unit operations including harvesting, cell disruption, extraction, and possibly fractionation.


Assuntos
Biotecnologia/economia , Filtração/métodos , Extração Líquido-Líquido/métodos , Microalgas/química , Proteínas de Algas/isolamento & purificação , Biocombustíveis/economia , Biomassa , Biotecnologia/métodos , Carboidratos/isolamento & purificação , Filtração/economia , Floculação , Humanos , Líquidos Iônicos/química , Lipídeos/isolamento & purificação , Extração Líquido-Líquido/economia , Microalgas/crescimento & desenvolvimento , Microalgas/isolamento & purificação , Micro-Ondas , Sonicação/economia , Sonicação/métodos
20.
Molecules ; 22(12)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29261155

RESUMO

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.


Assuntos
Carboidratos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Extratos Vegetais/análise , Polygala/química , Carboidratos/química , Carboidratos/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Controle de Qualidade
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