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2.
Physiol Rep ; 7(2): e13982, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30653856

RESUMO

This study investigated the effects of acute and chronic beetroot juice (BRJ) supplementation on submaximal exercise oxygen uptake (VO2 ), time trial (TT) performance, and contractile properties of the plantar flexors in females. Study 1: Using a double blind, randomized, crossover design, 12 recreationally active females using hormonal contraceptives supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d (~26 mmoles nitrate [ NO3- ]) or a NO3- -free placebo (PLA). On days 1 and 8, participants cycled for 10 min at 50% and 70% VO2peak and completed a 4 kJ/kg body mass TT. Plasma [ NO3- ] and nitrite ([NO2- ]) increased significantly following BRJ supplementation versus PLA. There was no effect of BRJ supplementation on VO2 at 50% or 70% VO2peak , or TT performance. Study 2: 12 recreationally active females (n = 7 from Study 1) using hormonal contraceptives participated in a baseline visit and were supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d. Maximum voluntary strength (MVC) of the plantar flexors was assessed and a torque-frequency curve performed. BRJ had no effect on MVC, voluntary activation, peak twitch torque, time to peak torque, or half relaxation time. Following both acute (46.6 ± 4.9% of 100 Hz torque) and chronic (47.2 ± 4.4%) supplementation, 10 Hz torque was significantly greater compared to baseline (32.9 ± 2.6%). In summary, BRJ may not be an effective ergogenic aid in recreationally active females as it did not reduce submaximal exercise VO2 or improve aerobic TT performance despite increasing low frequency torque production.


Assuntos
Antioxidantes/farmacologia , Desempenho Atlético/fisiologia , Beta vulgaris/química , Exercício Físico/fisiologia , Sucos de Frutas e Vegetais , Músculo Esquelético/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Adulto , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Adulto Jovem
3.
Environ Sci Pollut Res Int ; 26(3): 2026-2037, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28589276

RESUMO

The study focuses on the estimation of health risk from nitrate present in the drinking water and vegetables in Nagpur and Bhandara districts in the state of Maharashtra, India. Drinking water samples from 77 locations from the rural as well as urban areas and 22 varieties of vegetable were collected and analyzed for the presence of nitrate for a period of 1 year (two seasons). The daily intake of nitrate from these water and vegetable samples was then computed and compared with standard acceptable intake levels to assess the associated health risk. The mean nitrate concentration of 59 drinking water samples exceeded the Bureau of Indian Standards limit of 45 mg/L in drinking water. The rural and urban areas were found to have mean nitrate concentration in drinking water as 45.69 ± 2.08 and 22.53 ± 1.97 mg/L, respectively. The estimated daily intake of drinking water samples from 55 study sites had nitrate concentration far below the safety margin indicating serious health risk. The sanitation survey conducted in 12 households reported contaminated source with positive E. coli count in 20 samples as the major factor of health risk. The average nitrate concentration was maximum in beetroot (1349.38 mg/kg) followed by spinach (1288.75 mg/kg) and amaranthus (1007.64 mg/kg). Among the samples, four varieties of the vegetables exceeded the acceptable daily intake (ADI) with an assumption of 0.5 kg consumption of vegetables for an average of a 60-kg individual. Therefore, irrigation of these locally grown vegetables should be monitored periodically for nitrogen accumulation by the crop above the ADI limit. The application of nitrogenous fertilizers should also be minimized in the rural areas to help protect the nitrate contamination in groundwater sources.


Assuntos
Água Potável/química , Exposição Ambiental/análise , Nitratos/análise , Verduras/química , Poluentes Químicos da Água/análise , Amaranthus/química , Beta vulgaris/química , Ingestão de Líquidos , Água Potável/microbiologia , Ingestão de Alimentos , Escherichia coli/crescimento & desenvolvimento , Fertilizantes , Análise de Alimentos , Água Subterrânea/química , Humanos , Índia , Nitratos/efeitos adversos , Saúde Pública , Medição de Risco , População Rural , Saneamento , Spinacia oleracea/química , População Urbana , Poluentes Químicos da Água/efeitos adversos
4.
Microb Cell Fact ; 17(1): 190, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30501633

RESUMO

BACKGROUND: Efficient microbial production of chemicals is often hindered by the cytotoxicity of the products or by the pathogenicity of the host strains. Hence 2,3-butanediol, an important drop-in chemical, is an interesting alternative target molecule for microbial synthesis since it is non-cytotoxic. Metabolic engineering of non-pathogenic and industrially relevant microorganisms, such as Escherichia coli, have already yielded in promising 2,3-butanediol titers showing the potential of microbial synthesis of 2,3-butanediol. However, current microbial 2,3-butanediol production processes often rely on yeast extract as expensive additive, rendering these processes infeasible for industrial production. RESULTS: The aim of this study was to develop an efficient 2,3-butanediol production process with E. coli operating on the premise of using cost-effective medium without complex supplements, considering second generation feedstocks. Different gene donors and promoter fine-tuning allowed for construction of a potent E. coli strain for the production of 2,3-butanediol as important drop-in chemical. Pulsed fed-batch cultivations of E. coli W using microaerobic conditions showed high diol productivity of 4.5 g l-1 h-1. Optimizing oxygen supply and elimination of acetoin and by-product formation improved the 2,3-butanediol titer to 68 g l-1, 76% of the theoretical maximum yield, however, at the expense of productivity. Sugar beet molasses was tested as a potential substrate for industrial production of chemicals. Pulsed fed-batch cultivations produced 56 g l-1 2,3-butanediol, underlining the great potential of E. coli W as production organism for high value-added chemicals. CONCLUSION: A potent 2,3-butanediol producing E. coli strain was generated by considering promoter fine-tuning to balance cell fitness and production capacity. For the first time, 2,3-butanediol production was achieved with promising titer, rate and yield and no acetoin formation from glucose in pulsed fed-batch cultivations using chemically defined medium without complex hydrolysates. Furthermore, versatility of E. coli W as production host was demonstrated by efficiently converting sucrose from sugar beet molasses into 2,3-butanediol.


Assuntos
Beta vulgaris/química , Butileno Glicóis/química , Escherichia coli/metabolismo , Glucose/metabolismo , Engenharia Metabólica/métodos , Melaço/análise
5.
Regul Toxicol Pharmacol ; 92: 201-206, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29233770

RESUMO

The residual behavior of the systemic fungicide, metalaxyl, in Swiss chard cultivated at two different locations under greenhouse conditions was investigated using high-performance liquid chromatography coupled with an ultraviolet detector (HPLC-UVD). Samples were randomly collected over 14 days and extracted using acetonitrile, partitioned using solid sodium chloride, and a solid-phase extraction (SPE) NH2 cartridge was used for cleanup. The linearity over a concentration range 0.05-50 mg/L was excellent with a coefficient of determination (R2) of 0.9997. The recovery rate ranged from 77.05 to 88.92% with relative standard deviations (RSDs) ≤ 10.74, and the limits of detection (LOD) and quantification (LOQ) were 0.0033 and 0.01 mg/kg, respectively. The initial (2 h after application) deposits were 4.69 and 5.90 mg/kg for sites 1 and 2, respectively, which increased to 4.95 and 6.57 mg/kg, respectively, one day post-application, owing to the systemic properties of the fungicide. The dissipation half-life was 5.3 and 6.0 days for sites 1 and 2, respectively. The pre-harvest residue limit (PHRL) suggested that if 55.38 and 47.23 mg/kg was applied 10 days before harvest or 33.28 and 30.73 mg/kg was applied 5 days before harvest (for sites 1 and 2, respectively) then the concentration will fall below the maximum residue limit (MRL = 20.0 mg/kg) at the time of harvest. The dietary risk assessment, estimated as hazard quotient (RQ%), indicate that metalaxyl can be safely used in/on Swiss chard, with no hazardous effects expected for consumers.


Assuntos
Beta vulgaris/química , Fungicidas Industriais/análise , Fungicidas Industriais/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Alanina/análogos & derivados , Alanina/química , Dieta/métodos , Alimentos , Meia-Vida , Cinética , Limite de Detecção , Medição de Risco
6.
Biomed Chromatogr ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28731579

RESUMO

Residue analysis of dimethomorph in Swiss chard cultivated at two different locations under greenhouse conditions was conducted using high-performance liquid chromatography-ultraviolet detection and confirmed by tandem mass spectrometry. The randomly collected samples (over 14 days) were extracted with acetonitrile and purified using a Florisil solid-phase extraction cartridge. Linearity over a concentration range of 0.05-50.0 mg/L had an excellent coefficient of determination of 0.9996. Recovery rate ranged from 82.98 to 95.43% with relative standard deviations ≤5.12% and limits of detection and quantification of 0.003 and 0.01 mg/kg, respectively. The initial deposits [day 0 (2 h post-application)] were considerably lower (7.57 and 8.55 mg/kg for sites 1 and 2, respectively) than the maximum residue limit (30 mg/kg) set by the Korean Ministry of Food and Drug Safety. The dissipation half-life was approximately the same, being 5.0 and 5.1 days for sites 1 and 2, respectively. Risk assessment estimated as acceptable daily intake revealed a value of 0.084 or 0.094% (day 0) and 0.014% (10 days post-application), for sites 1 and 2, respectively. The values indicated that dimethomorph can be safely used on Swiss chard, with no hazardous effects expected for Korean consumers.


Assuntos
Beta vulgaris/química , Morfolinas/análise , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Inocuidade dos Alimentos , Limite de Detecção , Modelos Lineares , Morfolinas/química , Resíduos de Praguicidas/química , Reprodutibilidade dos Testes , República da Coreia , Medição de Risco , Espectrometria de Massas em Tandem/métodos
7.
J Microbiol Biotechnol ; 26(4): 675-83, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-26718465

RESUMO

One osmotolerant strain from among 44 yeast isolates was selected based on its growth abilities in media containing high concentrations of sucrose. This selected strain, named SKENNY, was identified as Meyerozyma guilliermondii by sequencing the internal transcribed spacer regions and partial D1/D2 large-subunit domains of the 26S ribosomal RNA. SK-ENNY was utilized to produce high-fructose glucose syrup (HFGS) from sucrose-containing biomass. Conversion rates to HFGS from 310-610 g/l of pure sucrose and from 75-310 g/l of sugar beet molasses were 73.5-94.1% and 76.2-91.1%, respectively. In the syrups produced, fructose yields were 89.4-100% and 96.5-100% and glucose yields were 57.6-82.5% and 55.3-79.5% of the theoretical values for pure sucrose and molasses sugars, respectively. This is the first report of employing M. guilliermondii for production of HFGS from sucrose-containing biomass.


Assuntos
Biomassa , Fermentação , Microbiologia de Alimentos/métodos , Xarope de Milho Rico em Frutose , Sacarose/análise , Leveduras/fisiologia , Beta vulgaris/química , Meios de Cultura , Microbiologia de Alimentos/economia , Frutose/análise , Glucose/análise , Melaço/microbiologia , RNA Ribossômico , Sacarose/metabolismo , Leveduras/genética
8.
Free Radic Biol Med ; 86: 200-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25998421

RESUMO

Dietary nitrate supplementation has been shown to reduce the oxygen (O2) cost of exercise and enhance exercise tolerance in healthy individuals. This study assessed whether similar effects could be observed in individuals with type 2 diabetes (T2DM). In a randomized, double-blind, placebo-controlled crossover study, 48 participants with T2DM supplemented their diet for 4 days with either nitrate-rich beetroot juice (70ml/day, 6.43mmol nitrate/day) or nitrate-depleted beetroot juice as placebo (70ml/day, 0.07mmol nitrate/day). After each intervention period, resting plasma nitrate and nitrite concentrations were measured subsequent to participants completing moderate-paced walking. Pulmonary gas exchange was measured to assess the O2 cost of walking. After a rest period, participants performed the 6-min walk test (6MWT). Relative to placebo, beetroot juice resulted in a significant increase in plasma nitrate (placebo, 57±66 vs beetroot, 319±110µM; P < 0.001) and plasma nitrite concentration (placebo, 680±256 vs beetroot, 1065±607nM; P < 0.001). There were no differences between placebo juice and beetroot juice for the O2 cost of walking (946±221 vs 939±223ml/min, respectively; P = 0.59) and distance covered in the 6MWT (550±83 vs 554±90m, respectively; P = 0.17). Nitrate supplementation did not affect the O2 cost of moderate-paced walking or improve performance in the 6MWT. These findings indicate that dietary nitrate supplementation does not modulate the response to exercise in individuals with T2DM.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Nitratos/administração & dosagem , Idoso , Antioxidantes/análise , Beta vulgaris/química , Terapia Combinada , Estudos Cross-Over , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Nutricionais , Método Duplo-Cego , Terapia por Exercício , Feminino , Sucos de Frutas e Vegetais/análise , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Resultado do Tratamento , Caminhada
9.
Environ Sci Pollut Res Int ; 22(15): 11236-54, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25794577

RESUMO

In the present study, sugar beet mud (SBM) and pulp (SBP) produced as a waste by-products of the sugar industry were mixed with cattle dung (CD) at different ratios on dry weight basis for vermicomposting with Eisenia fetida. Minimum mortality and highest population of worms were observed in 20:80 (SBM20) mixture of SBM and 10:90 (SBP10) ratios. However, increased percentages of wastes significantly affected the growth and fecundity of worms. Nutrients like nitrogen, phosphorus, sodium, increased from initial feed mixture to final products (i.e., vermicompost), while organic carbon (OC), C:N ratio and electrical conductivity (EC) declined in all the products of vermicomposting. Although there was an increase in the contents of all the heavy metals except copper, chromium, and iron in SBM, the contents were less than the international standards for compost which indicates that the vermicompost can be used in the fields without any ill effects on the soil. Allium cepa root chromosomal aberration assay was used to evaluate the genotoxicity of pre- and post-vermicomposted SBM to understand the effect of vermicomposting on the reduction of toxicity. Genotoxicity analysis of post-vermicomposted samples of SBM revealed 18-75% decline in the aberration frequencies. Scanning electron microscopy (SEM) was recorded to identify the changes in texture in the control and vermicomposted samples. The vermicomposted mixtures in the presence of earthworms confirm more numerous surface irregularities that prove to be good manure.


Assuntos
Beta vulgaris/química , Poluentes Ambientais/toxicidade , Resíduos Industriais , Testes de Mutagenicidade , Oligoquetos/metabolismo , Cebolas/efeitos dos fármacos , Solo , Animais , Biodegradação Ambiental , Carboidratos/química , Bovinos , Poluentes Ambientais/metabolismo , Cebolas/genética
10.
J Microbiol Biotechnol ; 25(2): 227-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25433551

RESUMO

Two recombinant arabinosyl hydrolases, α-L-arabinofuranosidase from Geobacillus sp. KCTC 3012 (GAFase) and endo-(1,5)-α-L-arabinanase from Bacillus licheniformis DSM13 (BlABNase), were overexpressed in Escherichia coli, and their synergistic modes of action against sugar beet (branched) arabinan were investigated. Whereas GAFase hydrolyzed 35.9% of L-arabinose residues from sugar beet (branched) arabinan, endo-action of BlABNase released only 0.5% of L-arabinose owing to its extremely low accessibility towards branched arabinan. Interestingly, the simultaneous treatment of GAFase and BlABNase could liberate approximately 91.2% of L-arabinose from arabinan, which was significantly higher than any single exo-enzyme treatment (35.9%) or even stepwise exo- after endo-enzyme treatment (75.5%). Based on their unique modes of action, both exo- and endo-arabinosyl hydrolases can work in concert to catalyze the hydrolysis of arabinan to L-arabinose. At the early stage in arabinan degradation, exo-acting GAFase could remove the terminal arabinose branches to generate debranched arabinan, which could be successively hydrolyzed into arabinooligosaccharides via the endoaction of BlABNase. At the final stage, the simultaneous actions of exo- and endo-hydrolases could synergistically accelerate the L-arabinose production with high conversion yield.


Assuntos
Arabinose/metabolismo , Glicosídeo Hidrolases/metabolismo , Polissacarídeos/metabolismo , Arabinose/economia , Bacillus/enzimologia , Beta vulgaris/química , Escherichia coli/genética , Geobacillus/enzimologia , Hidrólise , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
11.
J Environ Manage ; 144: 93-100, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24929500

RESUMO

The purpose of this study was to evaluate the effects of three agricultural processing wastes (APWs) on aggregate formation and aggregate stability in a sandy loam textured soil (Typic Xerofluvent) in Antalya, Turkey. The effects of APW applications on aggregate formation and aggregate stability were observed for different aggregate size groups (>4; 4-2; 2-1; 1-0.5; 0.5-0.25; 0.25-0.050 and <0.050 mm). Sugar Beet Pulp (SBP), Apple Pomace (AP) and Cotton Gin Waste (CGW) were applied to soil as fresh material (dry weight basis 0, 10, 20 and 40 t ha(-1)), and a greenhouse pot experiment was conducted using a completely randomized design with five replicates of each treatment. The study consisted of two periods. The first period (P1) consisted of a six-month incubation period (1st sample period). The second period (P2) is a six-month period and includes an eight-week green bean (Phaseolus vulgaris L.) growing process (2nd sample period). At the end of the first six months and fourteen months in total, aggregate formation and aggregate stability were determined and their correlation to different C sources was explained. At the end of the experiment, formation of aggregates was increased with increase in the application level of organic wastes in particular intermediate aggregates. Increase in the incubation time significantly enhanced the formation of particular macroaggregates. Soil aggregate stability of all aggregate sizes generally increased with the increasing in the level of implementation. In addition, incubation time effects on aggregate stability for macroaggregates were not significant, but significant for macro and microaggregates.


Assuntos
Agricultura , Phaseolus/efeitos dos fármacos , Phaseolus/crescimento & desenvolvimento , Poluentes do Solo/química , Beta vulgaris/química , Gossypium/química , Malus/química , Distribuição Aleatória , Turquia
12.
ChemSusChem ; 6(9): 1625-30, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24039080

RESUMO

As part of a long-term strategy toward renewable feedstock, a feasibility study into options for the production of bioethylene by integrating the sugar beet-to-ethanol-to-ethylene value chain. Seven business cases were studied and tested for actual economic feasibility of alternative sugar-to-ethanol-to-ethylene routes in comparison to fossil-fuel alternatives. An elaborate model was developed to assess the relevant operational and financial aspects of each business case. The calculations indicate that bioethylene from sugar beet is not commercially viable under current market conditions. In light of expected global energy and feedstock prices it is also reasonable to expect that this will not change in the near future. To consider biorenewable sources as starting material, they need to be low in cost (compared to sugar beets) and also require less capital and energy-intensive methods for the conversion to chemicals. In general, European sugar prices will be too high for many chemical applications. Future efforts for in sugar-to-chemicals routes should, therefore, focus on integrated process routes and process intensification and/or on products that contain a significant part of the original carbohydrate backbone.


Assuntos
Beta vulgaris/química , Etilenos/química , Química Verde/economia , Estudos de Viabilidade
13.
J Agric Food Chem ; 61(39): 9401-11, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24004410

RESUMO

Effects of biomass types (bark mulch versus sugar beet pulp) and carbonization processing conditions (temperature, residence time, and phase of reaction medium) on the chemical characteristics of hydrochars were examined by elemental analysis, solid-state ¹³C NMR, and chemical and biochemical oxygen demand measurements. Bark hydrochars were more aromatic than sugar beet hydrochars produced under the same processing conditions. The presence of lignin in bark led to a much lower biochemical oxygen demand (BOD) of bark than sugar beet and increasing trends of BOD after carbonization. Compared with those prepared at 200 °C, 250 °C hydrochars were more aromatic and depleted of carbohydrates. Longer residence time (20 versus 3 h) at 250 °C resulted in the enrichment of nonprotonated aromatic carbons. Both bark and sugar beet pulp underwent deeper carbonization during water hydrothermal carbonization than during steam hydrothermal carbonization (200 °C, 3 h) in terms of more abundant aromatic C but less carbohydrate C in water hydrochars.


Assuntos
Beta vulgaris/química , Carboidratos/química , Fertilizantes/análise , Jardinagem/métodos , Casca de Planta/química , Raízes de Plantas/química , Solo/química , Carboidratos/análise , Fertilizantes/economia , Indústria de Processamento de Alimentos/economia , Agricultura Florestal/economia , Jardinagem/economia , Temperatura Alta , Resíduos Industriais/análise , Resíduos Industriais/economia , Esterco , Odorantes , Oxigênio/química , Vapor , Fatores de Tempo , Água/química
14.
J Food Sci ; 77(4): C346-52, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22352766

RESUMO

Three dietary fibers (tomato fiber [TF], beet root fiber [BRF], and inulin) at 3 levels of addition (1%, 2%, and 3%) were assessed for the manufacture of chopped, cooked chicken products and compared with a control product without fiber added. The effect of fiber incorporation on (i) batters, (ii) cooked (30 min at 70 °C), and (iii) cooked and stored (for 10 d at 4 °C) chicken products were studied. The addition of the fiber to chicken meat products reduced the pH of chicken batters in proportional to the level of fiber addition. Fiber incorporation increased water-holding capacity but only the addition of TF reduced cook losses. The color of batters and cooked products was significantly modified by the type and level of fiber added. These changes were more noticeable when TF was added. Texture parameters were affected by the incorporation of TF and BRF; they increased the hardness in proportional to the level of addition. The addition of tomato and BRF to chicken meat products reduced lipid oxidation processes. These changes were dependent on the level of fiber added. The reduction of lipid oxidation processes was more marked in TF meat products than in products with other types of fibers. In contrast, the addition level of inulin increased TBA-RS numbers in chicken meat products. Although the addition of TF increased the redness of the meat products, the use of this fiber was more suitable as it reduced the extent of lipid oxidation processes. INDUSTRIAL APPLICATION: Nowadays, the reduction of fat and the increase of fiber content in meat products is one of the main goals of meat industry. Numerous sources of fiber can be added to the meat products; however, before that it is necessary to study their technological effect on raw and cooked meat products in order to evaluate their suitability for meat products manufacture. In addition, some of them could have beneficial effect on meat products conservation that could also increase their shelf life.


Assuntos
Beta vulgaris/química , Fibras na Dieta/análise , Alimentos Fortificados/análise , Inulina/química , Raízes de Plantas/química , Produtos Avícolas/análise , Solanum lycopersicum/química , Animais , Antioxidantes/análise , Antioxidantes/química , Fenômenos Químicos , Galinhas , Culinária , Dieta com Restrição de Gorduras , Fibras na Dieta/efeitos adversos , Fast Foods/análise , Frutas/química , Concentração de Íons de Hidrogênio , Inulina/efeitos adversos , Fenômenos Mecânicos , Oxirredução , Pigmentação , Refrigeração , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Água/análise
15.
Artigo em Inglês | MEDLINE | ID: mdl-24779784

RESUMO

Different parts of plant foods are generally discarded by consumers such as peel, stalk and leaves, which could however possess a nutritional value. However, few studies have analysed the composition of these marginal foods. The phenolic compound, flavonoid, polyamine, nitrate and pesticide contents of parts of vegetables that are usually discarded--but which were cultivated according to conventional and non-conventional procedures--were analysed to provide suggestions on how to improve the consumption of these parts and to reduce the production of urban solid waste. Few, but significant, differences between the two manuring procedures were observed. Higher nitrate content and the presence of organochlorine pesticides were found in conventional cultivated papaya peel, lemon balm leaves, jack fruit pulp, and beet stalk and peel. Discarded parts of plant foods such as stalk, leaves and peels can be used as a source of antioxidant compounds, such as phenolic compounds.


Assuntos
Antioxidantes/análise , Produtos Agrícolas/química , Fertilizantes , Contaminação de Alimentos/prevenção & controle , Alimentos Orgânicos/análise , Nitratos/análise , Resíduos de Praguicidas/análise , Resíduos/análise , Antioxidantes/economia , Antioxidantes/metabolismo , Artocarpus/química , Artocarpus/crescimento & desenvolvimento , Artocarpus/metabolismo , Beta vulgaris/química , Beta vulgaris/crescimento & desenvolvimento , Beta vulgaris/metabolismo , Brasil , Carica/química , Carica/crescimento & desenvolvimento , Carica/metabolismo , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Cymbopogon/química , Cymbopogon/crescimento & desenvolvimento , Cymbopogon/metabolismo , Poluentes Ambientais/análise , Poluentes Ambientais/metabolismo , Fertilizantes/efeitos adversos , Flavonoides/análise , Flavonoides/economia , Flavonoides/metabolismo , Alimentos Orgânicos/economia , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Ipomoea batatas/química , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Esterco , Nitratos/metabolismo , Agricultura Orgânica/métodos , Resíduos de Praguicidas/metabolismo , Fenóis/análise , Fenóis/economia , Fenóis/metabolismo , Resíduos/economia
16.
Food Sci Technol Int ; 17(6): 517-27, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22049159

RESUMO

The present work was dedicated to the development of an extraction process for red beet (Beta vulgaris L. var. conditiva) by-products that preserves the high molecular weight of the macromolecules with the primary aim of waste upgrading. Our study concerns the extraction of pectin-enriched products with potential thickening properties for their usage in food formulation, as well as with some healthy physiological effect, by using citrate buffer (pH = 5.2) either alone or with enzymes (hemicellulase or cellulase) active on cell wall polysaccharide networks. Considering that red beet tissue contains ferulic acid, which cross-links pectin macromolecules through arabinose residues to anchor them into the cell wall, an alkaline pretreatment was also evaluated in order to perform polysaccharide hydrolysis in the cell wall network to accomplish higher renderings. Chemical composition and yield, as well as the in vitro glucose retention exerted by the isolated fiber products were finally analyzed.


Assuntos
Beta vulgaris/química , Aditivos Alimentares/química , Aditivos Alimentares/isolamento & purificação , Pectinas/química , Pectinas/isolamento & purificação , Raízes de Plantas/química , Celulase/metabolismo , Diálise , Fibras na Dieta/análise , Fibras na Dieta/economia , Estudos de Viabilidade , Aditivos Alimentares/economia , Indústria de Processamento de Alimentos/economia , Proteínas Fúngicas/metabolismo , Glucose/análise , Glucose/química , Glicosídeo Hidrolases/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Peso Molecular , Pectinas/economia , Pectinas/metabolismo , Solubilidade , Resíduos/análise , Resíduos/economia
18.
J Appl Physiol (1985) ; 110(3): 591-600, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21071588

RESUMO

Dietary supplementation with beetroot juice (BR) has been shown to reduce resting blood pressure and the O(2) cost of submaximal exercise and to increase tolerance to high-intensity cycling. We tested the hypothesis that the physiological effects of BR were consequent to its high NO(3)(-) content per se, and not the presence of other potentially bioactive compounds. We investigated changes in blood pressure, mitochondrial oxidative capacity (Q(max)), and physiological responses to walking and moderate- and severe-intensity running following dietary supplementation with BR and NO(3)(-)-depleted BR [placebo (PL)]. After control (nonsupplemented) tests, nine healthy, physically active male subjects were assigned in a randomized, double-blind, crossover design to receive BR (0.5 l/day, containing ∼6.2 mmol of NO(3)(-)) and PL (0.5 l/day, containing ∼0.003 mmol of NO(3)(-)) for 6 days. Subjects completed treadmill exercise tests on days 4 and 5 and knee-extension exercise tests for estimation of Q(max) (using (31)P-magnetic resonance spectroscopy) on day 6 of the supplementation periods. Relative to PL, BR elevated plasma NO(2)(-) concentration (183 ± 119 vs. 373 ± 211 nM, P < 0.05) and reduced systolic blood pressure (129 ± 9 vs. 124 ± 10 mmHg, P < 0.01). Q(max) was not different between PL and BR (0.93 ± 0.05 and 1.05 ± 0.22 mM/s, respectively). The O(2) cost of walking (0.87 ± 0.12 and 0.70 ± 0.10 l/min in PL and BR, respectively, P < 0.01), moderate-intensity running (2.26 ± 0.27 and 2.10 ± 0.28 l/min in PL and BR, respectively, P < 0.01), and severe-intensity running (end-exercise O(2) uptake = 3.77 ± 0.57 and 3.50 ± 0.62 l/min in PL and BL, respectively, P < 0.01) was reduced by BR, and time to exhaustion during severe-intensity running was increased by 15% (7.6 ± 1.5 and 8.7 ± 1.8 min in PL and BR, respectively, P < 0.01). In contrast, relative to control, PL supplementation did not alter plasma NO(2)(-) concentration, blood pressure, or the physiological responses to exercise. These results indicate that the positive effects of 6 days of BR supplementation on the physiological responses to exercise can be ascribed to the high NO(3)(-) content per se.


Assuntos
Beta vulgaris/química , Suplementos Nutricionais , Nitratos/administração & dosagem , Consumo de Oxigênio/fisiologia , Extratos Vegetais/administração & dosagem , Corrida/fisiologia , Caminhada/fisiologia , Administração Oral , Bebidas , Marcha/efeitos dos fármacos , Marcha/fisiologia , Humanos , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Adulto Jovem
19.
J Sci Food Agric ; 90(13): 2188-94, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20607794

RESUMO

BACKGROUND: Recycling of organic byproducts for use as soil amendments or fertilisers may enhance the productivity of soils. The aim of this study was to investigate the potential of sugar beet vinasse to correct iron chlorosis in crops when applied in conjunction with Fe fertilisers such as vivianite and ferrous sulfate (FS). An experiment involving two factors (Fe source and dialysed sugar beet vinasse (DBV) rate) was performed using white lupin (Lupinus albus L.) and calcareous sand as growing medium. RESULTS: Although vivianite provided lower chlorophyll contents than Fe-chelate, dry matter production was not significantly different between the two Fe sources. Vivianite was more effective than FS in preventing iron chlorosis in white lupin, but not when DBV was applied. DBV significantly increased chlorophyll content in plants treated with FS after 3 weeks of growth. CONCLUSION: DBV increased the effect of FS in preventing iron deficiency chlorosis in white lupin. This was due, at least in part, to the inhibition of the precipitation of Fe oxides by organic compounds and to the increase in the content of Fe complexed by organic compounds in the growing medium, as revealed by sequential Fe fractionation.


Assuntos
Beta vulgaris/química , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes/análise , Resíduos Industriais/análise , Ferro/análise , Lupinus/química , Lupinus/crescimento & desenvolvimento , Clorofila/análise , Produtos Agrícolas/química , Produtos Agrícolas/economia , Diálise , Sacarose Alimentar , Etilenodiaminas , Compostos Ferrosos , Indústria de Processamento de Alimentos/economia , Resíduos Industriais/economia , Ferro/química , Fosfatos , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/crescimento & desenvolvimento , Dióxido de Silício , Fatores de Tempo
20.
Ultrason Sonochem ; 16(6): 782-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19410496

RESUMO

There is a growing demand for eco-friendly/non-toxic colorants, specifically for health sensitive applications such as coloration of food and dyeing of child textile/leather garments. Recently, dyes derived from natural sources for these applications have emerged as an important alternative to potentially harmful synthetic dyes and pose need for suitable effective extraction methodologies. The present paper focus on the influence of process parameters for ultrasound assisted leaching of coloring matter from plant materials. In the present work, extraction of natural dye from beetroot using ultrasound has been studied and compared with static/magnetic stirring as a control process at 45 degrees C. The influence of process parameters on the extraction efficiency such as ultrasonic output power, time, pulse mode, effect of solvent system and amount of beetroot has been studied. The use of ultrasound is found to have significant improvement in the extraction efficiency of colorant obtained from beetroot. Based on the experiments it has been found that a mixture of 1:1 ethanol-water with 80W ultrasonic power for 3h contact time provided better yield and extraction efficiency. Pulse mode operation may be useful in reducing electrical energy consumption in the extraction process. The effect of the amount of beetroot used in relation to extraction efficiency has also been studied. Two-stage extraction has been studied and found to be beneficial for improving the yield for higher amounts of beetroot. Significant 8% enhancement in % yield of colorant has been achieved with ultrasound, 80W as compared to MS process both using 1:1 ethanol-water. The coloring ability of extracted beet dye has been tested on substrates such as leather and paper and found to be suitable for dyeing. Ultrasound is also found to be beneficial in natural dyeing of leather with improved rate of exhaustion. Both the dyed substrates have better color values for ultrasonic beet extract as inferred from reflectance measurement. Therefore, the present study clearly offers efficient extraction methodology from natural dye resources such as beetroot with ultrasound even dispensing with external heating. Thereby, also making eco-friendly non-toxic dyeing of fibrous substances a potential viable option.


Assuntos
Beta vulgaris/química , Produtos Biológicos/isolamento & purificação , Vestuário , Corantes/isolamento & purificação , Química Verde/métodos , Curtume/métodos , Ultrassom , Produtos Biológicos/química , Cor , Corantes/química , Química Verde/economia , Magnetismo , Raízes de Plantas/química , Solventes/química , Fatores de Tempo
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