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1.
J Environ Sci (China) ; 87: 24-38, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791497

RESUMO

Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands, but phytoremediation without economic revenue is unfeasible for land owners and farmers. The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities. Sunflower (Helianthus annuus L.) is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages (biomass and oil). In this study, 40 germplasms of sunflower were screened in field conditions for phytoremediation with the possibility for oil and meal production. The study was carried out to the physiological maturity stage. All studied germplasms mopped up substantial concentrations of Pb, with maximum amounts in shoot > root > seed respectively. The phytoextraction efficiency of the germplasm was assessed in terms of the Transfer factor (TF), Metal removal efficiency (MRE) and Metal extraction ratio (MER). Among all assessed criteria, GP.8585 was found to be most appropriate for restoring moderately Pb-contaminated soil accompanied with providing high biomass and high yield production. The Pb content in the oil of GP.8585 was below the Food safety standard of China, with 59.5% oleic acid and 32.1% linoleic acid. Moreover, amino acid analysis in meal illustrated significant differences among essential and non-essential amino acids. Glutamic acid was found in the highest percentage (22.4%), whereas cysteine in the lowest percentage (1.3%). Therefore, its efficient phytoextraction ability and good quality edible oil and meal production makes GP.8585 the most convenient sunflower germplasm for phytoremediation of moderately Pb-contaminated soil, with fringe benefits to farmers and landowners.


Assuntos
Biodegradação Ambiental , Helianthus/fisiologia , Chumbo , Poluentes do Solo/análise , Agricultura , Animais , Asteraceae , Biomassa , China , Produtos Agrícolas , Poluentes Ambientais , Helianthus/química , Humanos , Metais Pesados , Sementes/química , Solo
2.
Sensors (Basel) ; 18(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134620

RESUMO

This study considers whether a relationship exists between response to lithium (Li) exposure and select vegetation indices (VI) determined from reflectance spectra in each of four plant species: Arabidopsis thaliana, Helianthus annuus (sunflower), Brassica napus (rape), and Zea mays (corn). Reflectance spectra were collected every week for three weeks using an ASD FieldSpec Pro spectroradiometer with both a contact probe (CP) and a field of view probe (FOV) for plants treated twice weekly in a laboratory setting with 0 mM (control) or 15 mM of lithium chloride (LiCl) solution. Plants were harvested each week after spectra collection for determination of relevant physical endpoints such as relative water content and chlorophyll content. Mixed effects analyses were conducted on selected endpoints and vegetation indices (VI) to determine the significance of the effects of treatment level and length of treatment as well as to determine which VI would be appropriate predictors of treatment-dependent endpoints. Of the species considered, A. thaliana exhibited the most significant effects and corresponding shifts in reflectance spectra. Depending on the species and endpoint, the most relevant VIs in this study were NDVI, PSND, YI, R1676/R1933, R750/R550, and R950/R750.


Assuntos
Arabidopsis/efeitos dos fármacos , Brassica napus/efeitos dos fármacos , Helianthus/efeitos dos fármacos , Cloreto de Lítio/farmacologia , Zea mays/efeitos dos fármacos , Arabidopsis/química , Brassica napus/química , Clorofila/análise , Helianthus/química , Água/análise , Zea mays/química
3.
J Biol Chem ; 292(30): 12398-12411, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28536266

RESUMO

Seed storage proteins are both an important source of nutrition for humans and essential for seedling establishment. Interestingly, unusual napin-type 2S seed storage albumin precursors in sunflowers contain a sequence that is released as a macrocyclic peptide during post-translational processing. The mechanism by which such peptides emerge from linear precursor proteins has received increased attention; however, the structural characterization of intact precursor proteins has been limited. Here, we report the 3D NMR structure of the Helianthus annuus PawS1 (preproalbumin with sunflower trypsin inhibitor-1) and provide new insights into the processing of this remarkable dual-destiny protein. In seeds, PawS1 is matured by asparaginyl endopeptidases (AEPs) into the cyclic peptide SFTI-1 (sunflower trypsin inhibitor-1) and a heterodimeric 2S albumin. The structure of PawS1 revealed that SFTI-1 and the albumin are independently folded into well-defined domains separated by a flexible linker. PawS1 was cleaved in vitro with recombinant sunflower HaAEP1 and in situ using a sunflower seed extract in a way that resembled the expected in vivo cleavages. Recombinant HaAEP1 cleaved PawS1 at multiple positions, and in situ, its flexible linker was removed, yielding fully mature heterodimeric albumin. Liberation and cyclization of SFTI-1, however, was inefficient, suggesting that specific seed conditions or components may be required for in vivo biosynthesis of SFTI-1. In summary, this study has revealed the 3D structure of a macrocyclic precursor protein and provided important mechanistic insights into the maturation of sunflower proalbumins into an albumin and a macrocyclic peptide.


Assuntos
Helianthus/química , Peptídeos Cíclicos/química , Pré-Albumina/química , Peptídeos Cíclicos/metabolismo , Pré-Albumina/metabolismo , Conformação Proteica , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo
4.
Environ Sci Pollut Res Int ; 23(22): 22633-22646, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27557966

RESUMO

The land disposal of waste and wastewater is a major source of N2O emission. This is due to the presence of high concentrations of nitrogen (N) and carbon in the waste. Abattoir wastewater contains 186 mg/L of N and 30.4 mg/L of P. The equivalent of 3 kg of abattoir wastewater-irrigated soil was sieved and taken in a 4-L plastic container. Abattoir wastewater was used for irrigating the plants at the rates of 50 and 100 % field capacity (FC). Four crop species were used with no crop serving as a control. Nitrous oxide emission was monitored using a closed chamber technique. The chamber was placed inside the plastic container, and N2O emission was measured for 7 days after the planting. A syringe and pre-evacuated vial were used for collecting the gas samples; a fresh and clean syringe was used each time to avoid cross-contamination. The collected gas samples were injected into a gas chromatography device immediately after each sampling to analyse the concentration of N2O from different treatments. The overall N2O emission was compared for all the crops under two different abattoir wastewater treatment rates (50 and 100 % FC). Under 100 % FC (wastewater irrigation), among the four species grown in the abattoir wastewater-irrigated soil, Medicago sativa (23 mg/pot), Sinapis alba (21 mg/pot), Zea mays (20 mg/pot) and Helianthus annuus (20 mg/pot) showed higher N2O emission compared to the 50 % treatments-M. sativa (17 mg/pot), S. alba (17 mg/pot), Z. mays (18 mg/pot) and H. annuus (18 mg/pot). Similarly, pots with plants have shown 15 % less emission than the pots without plants. Similar trends of N2O emission flux were observed between the irrigation period (4-week period) for 50 % FC and 100 % FC. Under the 100 % FC loading rate treatments, the highest N2O emission was in the following order: week 1 > week 4 > week 3 > week 2. On the other hand, under the 50 % FC loading rate treatments, the highest N2O emission was recorded in the first few weeks and in the following order: week 1 > week 2 > week 3 > week > 4. Since N2O is a greenhouse gas with high global warming potential, its emission from wastewater irrigation is likely to impact global climate change. Therefore, it is important to examine the effects of abattoir wastewater irrigation on soil for N2O emission potential.


Assuntos
Nitrogênio/análise , Óxido Nitroso/análise , Solo/química , Águas Residuárias/análise , Matadouros , Irrigação Agrícola , Dióxido de Carbono/análise , Mudança Climática , Helianthus/química , Helianthus/crescimento & desenvolvimento , Medicago sativa/química , Medicago sativa/crescimento & desenvolvimento , Sinapis/química , Sinapis/crescimento & desenvolvimento , Zea mays/química , Zea mays/crescimento & desenvolvimento
5.
J Biosci Bioeng ; 121(1): 66-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26149719

RESUMO

Lignocellulosic biomass and dedicated energy crops such as Jerusalem artichoke are promising alternatives for biobutanol production by solventogenic clostridia. However, fermentable sugars such as fructose or xylose released from the hydrolysis of these feedstocks were subjected to the incomplete utilization by the strains, leading to relatively low butanol production and productivity. When 0.001 g/L ZnSO4·7H2O was supplemented into the medium containing fructose as sole carbon source, 12.8 g/L of butanol was achieved with butanol productivity of 0.089 g/L/h compared to only 4.5 g/L of butanol produced with butanol productivity of 0.028 g/L/h in the control without zinc supplementation. Micronutrient zinc also led to the improved butanol production up to 8.3 g/L derived from 45.2 g/L xylose as sole carbon source with increasing butanol productivity by 31.7%. Moreover, the decreased acids production was observed under the zinc supplementation condition, resulting in the increased butanol yields of 0.202 g/g-fructose and 0.184 g/g-xylose, respectively. Similar improvements were also observed with increasing butanol production by 130.2 % and 8.5 %, butanol productivity by 203.4% and 18.4%, respectively, in acetone-butanol-ethanol fermentations from sugar mixtures of fructose/glucose (4:1) and xylose/glucose (1:2) simulating the hydrolysates of Jerusalem artichoke tubers and corn stover. The results obtained from transcriptional analysis revealed that zinc may have regulatory mechanisms for the sugar transport and metabolism of Clostridium acetobutylicum L7. Therefore, micronutrient zinc supplementation could be an effective way for economic development of butanol production derived from these low-cost agricultural feedstocks.


Assuntos
1-Butanol/metabolismo , Acetona/metabolismo , Etanol/metabolismo , Fermentação , Frutose/metabolismo , Xilose/metabolismo , Zinco/metabolismo , Biomassa , Metabolismo dos Carboidratos/efeitos dos fármacos , Clostridium acetobutylicum/efeitos dos fármacos , Clostridium acetobutylicum/metabolismo , Fermentação/efeitos dos fármacos , Glucose/metabolismo , Helianthus/química , Helianthus/metabolismo , Zea mays/química , Zea mays/metabolismo , Zinco/farmacologia
6.
Int J Mol Sci ; 16(4): 8997-9016, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25913379

RESUMO

Biorefinery applications are receiving growing interest due to climatic and waste disposal issues and lack of petroleum resources. Jerusalem artichoke (Helianthus tuberosus L.) is suitable for biorefinery applications due to high biomass production and limited cultivation requirements. This paper focuses on the potential of Jerusalem artichoke as a biorefinery crop and the most viable products in such a case. The carbohydrates in the tubers were found to have potential for production of platform chemicals, e.g., succinic acid. However, economic analysis showed that production of platform chemicals as a single product was too expensive to be competitive with petrochemically produced sugars. Therefore, production of several products from the same crop is a must. Additional products are protein based ones from tubers and leaves and biogas from residues, although both are of low value and amount. High bioactive activity was found in the young leaves of the crop, and the sesquiterpene lactones are of specific interest, as other compounds from this group have shown inhibitory effects on several human diseases. Thus, future focus should be on understanding the usefulness of small molecules, to develop methods for their extraction and purification and to further develop sustainable and viable methods for the production of platform chemicals.


Assuntos
Helianthus/química , Extratos Vegetais/química , Produtos Agrícolas/química , Humanos , Lactonas/química , Lactonas/economia , Lactonas/isolamento & purificação , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Proteínas de Plantas/química , Proteínas de Plantas/economia , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/química , Sesquiterpenos/química , Sesquiterpenos/economia , Sesquiterpenos/isolamento & purificação
7.
J Appl Microbiol ; 118(3): 609-18, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25494982

RESUMO

AIMS: Through biodesulphurization (BDS) is possible to remove the sulphur present in fossil fuels to carry out the very strict legislation. However, this biological process is limited by the cost of the culture medium, and thus, it is important to explore cheaper alternative carbon sources, such as Jerusalem artichoke (JA). These carbon sources usually contain sulphates which interfere with the BDS process. The goal of this work was to remove the sulphates from Jerusalem artichoke juice (JAJ) through BaCl2 precipitation viewing the optimization of dibenzothiophene (DBT) desulphurization by Gordonia alkanivorans strain 1B. METHODS AND RESULTS: Using a statistical design (Doehlert distribution), the effect of BaCl2 concentration (0.125-0.625%) and pH (5-9) was studied on sulphate concentration in hydrolysed JAJ. A validated surface response derived from data indicated that zero sulphates can be achieved with 0.5-0.55% (w/v) BaCl2 at pH 7; however, parallel BDS assays showed that the highest desulphurization was obtained with the juice treated with 0.5% (w/v) BaCl2 at pH 8.73. Further assays demonstrated that enhanced DBT desulphurization was achieved using hydrolysed JAJ treated in these optimal conditions. A total conversion of 400 µmol l(-1) DBT into 2-hydroxybiphenyl (2-HBP) in <90 h was observed, attaining a 2-HBP maximum production rate of 28.2 µmol l(-1) h(-1) and a specific production rate of 5.06 µmol(-1) g(-1) (DCW) h(-1) . CONCLUSIONS: These results highlight the efficacy of the treatment applied to JAJ in making this agromaterial a promising low-cost renewable feedstock for improved BDS by the fructophilic strain 1B. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is a fundamental step viewing BDS application at the industrial level as it accounts a cost-effective production of the biocatalysts, one of the main drawbacks for BDS scale-up.


Assuntos
Combustíveis Fósseis , Frutose/metabolismo , Bactéria Gordonia/metabolismo , Helianthus/química , Enxofre/metabolismo , Carbono/metabolismo , Tiofenos/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-23665483

RESUMO

A simple and fast procedure is described for evaluating the antioxidant activity of hydrophilic and hydrophobic compounds by using the peroxyoxalate-chemiluminescence (PO-CL) reaction of Bis(2,4,6-trichlorophenyl) oxalate (TCPO) with hydrogen peroxide in the presence of di(tert-butyl)2-(tert-butylamino)-5-[(E)-2-phenyl-1-ethenyl]3,4-furandicarboxylate as a highly fluorescent fluorophore. The IC50 values of the well-known antioxidants were calculated and the results were expressed as gallic equivalent antioxidant capacity (GEAC). It was found that the proposed method is free of physical quenching and oxidant interference, for this reason, proposed method is able to determine the accurate scavenging activity of the antioxidants to the free radicals. Finally, the proposed method was applied to the evaluation of antioxidant activity of complex real samples such as soybean oil and sunflower oil (as hydrophobic samples) and honey (as hydrophilic sample). To the best of our knowledge, this is the first time that total antioxidant activity can be determined directly in soybean oil, sunflower oil and honey (not in their extracts) using PO-CL reactions.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Radicais Livres/metabolismo , Medições Luminescentes/métodos , Oxalatos/química , Corantes Fluorescentes/química , Helianthus/química , Mel/análise , Peróxido de Hidrogênio/química , Interações Hidrofóbicas e Hidrofílicas , Luminescência , Medições Luminescentes/economia , Óleos de Plantas/química , Óleo de Soja/química
9.
J Agric Food Chem ; 61(14): 3435-42, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23510166

RESUMO

Ray florets (Rf) and disc florets (Df) are agricultural byproducts of sunflower seeds. Their nutrition-related compounds were determined. The dietary fiber contents in Rf and Df were 42.90 mg/100 g and 58.97 mg/100 g. In both florets, palmitic, linoleic, and linolenic acids were identified as the three most abundant fatty acids, and the saturated ones constitute approximately two-thirds (w/w) of the total fatty acids. Lysine was the limiting amino acid in both florets by World Health Organization standards. Sixteen phenolic compounds, nine free and eight bound, mainly depsides, were identified in florets by RP-HPLC-DAD/ESI-TOF-MS. The free and bound phenolic compounds in Df were higher than in Rf. 1,5-di-O-caffeoylquinic acid was the predominant free phenolic compound in both florets. The present study revealed that the florets of sunflower are rich sources of dietary fiber, Fe, and phenols.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Helianthus/química , Inflorescência/química , Fenóis/análise , Agricultura/economia , Antioxidantes/química , Antioxidantes/economia , Antioxidantes/isolamento & purificação , China , Fibras na Dieta/economia , Ferro da Dieta/análise , Ferro da Dieta/economia , Ferro da Dieta/isolamento & purificação , Fenóis/química , Fenóis/economia , Fenóis/isolamento & purificação , Resíduos/análise , Resíduos/economia
10.
Prep Biochem Biotechnol ; 42(3): 249-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22509850

RESUMO

Vegetable edible oils and fats are mainly used for frying purposes in households and the food industry. The oil undergoes degradation during frying and hence has to be replaced from time to time. Rhamnolipids are produced by microbial cultivation using refined vegetable oils as a carbon source and Pseudomonas aeruginosa (ATCC 10145). The raw material cost accounts for 10-30% of the overall cost of biosurfactant production and can be reduced by using low-cost substrates. In this research, attention was focused on the preparation of rhamnolipids, which are biosurfactants, using potential frying edible oils as a carbon source via a microbial fermentation technique. The use of low-cost substrates as a carbon source was emphasized to tilt the cost of production for rhamnolipids. The yield was 2.8 g/L and 7.5 g/L from waste frying oil before and after activated earth treatment, respectively. The crude product contained mainly dirhamnolipids, confirmed by thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), liquid chromatography-mass spectroscopy (LC-MS), and (1)H-nuclear magnetic resonance (NMR). Hence, the treatment can be used to convert waste frying oil as a low-cost substrate into a cost-effective carbon source.


Assuntos
Glicolipídeos/biossíntese , Óleos de Plantas/química , Pseudomonas aeruginosa/química , Biodegradação Ambiental , Carbono/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Fermentação , Helianthus/química , Temperatura Alta , Ácido Linoleico/química , Espectroscopia de Ressonância Magnética , Peróxidos/análise , Peróxidos/química , Óleos de Plantas/análise , Pressão , Pseudomonas aeruginosa/crescimento & desenvolvimento , Óleo de Girassol , Tensão Superficial , Tensoativos/química , Fatores de Tempo , Viscosidade , Resíduos/análise
11.
Int J Food Sci Nutr ; 63(2): 160-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21854109

RESUMO

Headspace-solid-phase microextraction-gas chromatography (HS-SPME-GC) was used to identify in total 74 volatile lipid oxidation compounds altogether in thermally stressed conventional and high-oleic sunflower (HOSF) oil samples (in accelerated storage conditions for 14 days at 80°C). Out of the volatile compounds identified, six volatile compounds were selected as marker compounds for the assessment of lipid oxidation of sunflower (SF) and HOSF oils due to their low odour threshold values and fatty-rancid odour impression. Additionally, other oxidation parameters such as fatty acid composition, peroxide value (PV), anisidine value and tocopherol and tocotrienol composition were determined. Multivariate statistical methods (principal component analysis and agglomerative hierarchical cluster analysis) were applied to identify sensitive oxidation marker compounds. Preliminary results revealed that hexanal, E-2-heptenal, E-2-decenal and E,E-2,4-nonadienal were the most suitable in differentiating HOSF and SF oil varieties from each other and SF samples with differing oxidative properties. Differentiation of SF samples according to their volatile compound composition was done in accordance with the results from the well-known oil quality parameters (e.g. PV or fatty acid composition). In conclusion, the combination of volatile compound analysis with HS-SPME-GC and multivariate statistical methods provides a sensitive tool in differentiating conventional SF and HOSF oils by means of volatile lipid oxidation marker compounds.


Assuntos
Cromatografia Gasosa/métodos , Helianthus/química , Peroxidação de Lipídeos , Ácido Oleico/metabolismo , Óleos de Plantas/metabolismo , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/metabolismo , Análise por Conglomerados , Gorduras na Dieta/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Temperatura Alta , Análise Multivariada , Odorantes , Oxirredução , Análise de Componente Principal , Reprodutibilidade dos Testes , Estresse Fisiológico , Óleo de Girassol , Tocoferóis/metabolismo , Tocotrienóis/análise , Tocotrienóis/metabolismo
12.
J Sci Food Agric ; 90(9): 1508-12, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20549804

RESUMO

BACKGROUND: The main purpose of this study was to examine the technical efficiency of farms producing sunflower in Erzurum, Turkey and to identify factors that might be causing inefficiency. Stochastic frontier analysis was used to measure technical efficiency. One hundred and seventeen randomly selected farms were interviewed for farm-level data in the 2004-2005 production period. RESULTS: Results revealed that the mean technical efficiency for the sunflower farms, estimated by the stochastic production frontier, is 64%. At full technical efficiency, on average, the farmers could reduce their inputs by around 56% without reducing their sunflower production, simply by improving technical efficiency. In the inefficiency model the parameter estimates showed that older farmers, higher level of farmer's education, more experienced farmers, larger farm size and higher information score resulted in lower technical inefficiency, while bigger family size and more credit usage resulted in higher technical inefficiency. CONCLUSION: This study proposes strategies such as providing better extension services and farmer-training programmes, including more educated people in sunflower farming and also expanding the sunflower-growing area through provision of adequate facilities in order to increase technical efficiency.


Assuntos
Agricultura/métodos , Helianthus/química , Helianthus/crescimento & desenvolvimento , Óleos de Plantas , Sementes/química , Sementes/crescimento & desenvolvimento , Agricultura/economia , Agricultura/educação , Escolaridade , Características da Família , Humanos , Modelos Econômicos , Óleos de Plantas/economia , Processos Estocásticos , Óleo de Girassol , Turquia
13.
Appl Microbiol Biotechnol ; 82(5): 847-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19122999

RESUMO

2,3-Butanediol is one of the promising bulk chemicals with wide applications. Its fermentative production has attracted great interest due to the high end concentration. However, large-scale production of 2,3-butanediol requires low-cost substrate and efficient fermentation process. In the present study, 2,3-butanediol production by Klebsiella pneumoniae from Jerusalem artichoke tubers was successfully performed, and various technologies, including separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF), were investigated. The concentration of target products reached 81.59 and 91.63 g/l, respectively after 40 h in batch and fed-batch SSF processes. Comparing with fed-batch SHF, the fed-batch SSF provided 30.3% higher concentration and 83.2% higher productivity of target products. The results showed that Jerusalem artichoke tuber is a favorable substrate for 2,3-butanediol production, and the application of fed-batch SSF for its conversion can result in a more cost-effective process.


Assuntos
Butileno Glicóis/metabolismo , Helianthus/química , Klebsiella pneumoniae/metabolismo , Butileno Glicóis/química , Fermentação , Helianthus/metabolismo , Hidrólise , Microbiologia Industrial/economia , Microbiologia Industrial/métodos , Inulina/metabolismo , Fatores de Tempo
14.
Z Naturforsch C J Biosci ; 62(5-6): 367-72, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17708442

RESUMO

Phytotoxicity of parthenin, a sesquiterpene lactone, was evaluated against four weedy species (Amaranthus viridis, Cassia occidentalis, Echinochloa crus-galli, and Phalaris minor) through a series of experiments conducted under laboratory or greenhouse conditions to assess its herbicidal potential. Under laboratory conditions, parthenin (0.5-2 mM) severely reduced seedling growth (root and shoot) and dry weight of test weeds. However, the effect was greater on root growth. Parthenin (1 mM) suppressed the mitotic activity in the onion root tip cells that could possibly be responsible for the reduction in seedling growth. Both pre- and post-emergent application of parthenin caused a significant loss of chlorophyll pigments and affected photosynthesis. Parthenin ( > or =1 mM) caused an excessive electrolyte leakage in the plant tissues which was light-dependent. The root inhibition was associated with swelling and blackening of the root tip, shriveling and damage to the epidermal tissue and non-formation of root hairs. The study concludes that parthenin possesses weed-suppressing potential (both pre- and post-).


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Helianthus/química , Células Vegetais , Sesquiterpenos/toxicidade , Alérgenos/toxicidade , Clorofila/fisiologia , Helianthus/fisiologia , Cebolas/citologia , Cebolas/efeitos dos fármacos , Fotossíntese , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Plantas/efeitos dos fármacos
15.
J Hazard Mater ; 147(3): 900-5, 2007 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-17321679

RESUMO

In this paper, the potential of two low-cost adsorbents such as sunflower seed shells (SS) and mandarin peelings (MP) in the removal of the synthetic anionic dye Reactive Black 5 (RB5) from aqueous solutions was investigated. SS led to a percentage of dye removal higher than MP (85% and 71% after 210min, respectively, for an initial RB5 concentration of 50mgL(-1) and an initial pH of 2.0). The rate of adsorption followed a pseudo-second-order kinetic model and the intra-particle diffusion was found to be the rate-controlling stage. In addition, the equilibrium data fitted well both the Freundlich and multilayer adsorption isotherm equations indicating the heterogeneity of the adsorbent surface. This was also corroborated by the SEM photographs. On the whole, the results in this study indicated that SS were very attractive materials for removing anionic dyes from dyed effluents.


Assuntos
Helianthus/química , Naftalenossulfonatos/isolamento & purificação , Sementes/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Custos e Análise de Custo , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Soluções
16.
Pediatr Infect Dis J ; 23(8): 719-25, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15295221

RESUMO

BACKGROUND: Because the therapeutic options for managing infections in neonates in developing countries are often limited, innovative approaches to preventing infections are needed. Topical therapy with skin barrier-enhancing products may be an effective strategy for improving neonatal outcomes, particularly among preterm, low birth weight infants whose skin barrier is temporarily but critically compromised as a result of immaturity. METHODS: We tested the impact of topical application of sunflower seed oil 3 times daily to preterm infants <34 weeks gestational age at the Kasr El-Aini neonatal intensive care unit at Cairo University on skin condition, rates of nosocomial infections and mortality. RESULTS: Treatment with sunflower seed oil (n = 51) resulted in a significant improvement in skin condition (P = 0.037) and a highly significant reduction in the incidence of nosocomial infections (adjusted incidence ratio, 0.46; 95% confidence interval, 0.26-0.81; P = 0.007) compared with infants not receiving topical prophylaxis (n = 52). There were no reported adverse events as a result of topical therapy. CONCLUSIONS: Given the low cost (approximately .20 dollars for a course of therapy) and technologic simplicity of the intervention and the effect size observed in this study, a clinical trial with increased numbers of subjects is indicated to evaluate the potential of topical therapy to reduce infections and save newborn lives in developing countries.


Assuntos
Infecções Bacterianas/prevenção & controle , Infecção Hospitalar/prevenção & controle , Países em Desenvolvimento , Recém-Nascido Prematuro , Óleos de Plantas/uso terapêutico , Administração Tópica , Esquema de Medicação , Custos de Medicamentos , Feminino , Helianthus/química , Humanos , Recém-Nascido , Doenças do Recém-Nascido , Masculino , Excipientes Farmacêuticos , Óleos de Plantas/administração & dosagem , Óleos de Plantas/farmacologia , Óleo de Girassol
17.
J Agric Food Chem ; 50(6): 1362-7, 2002 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11879003

RESUMO

We report on the development of a novel alternative method for the assessment of floral origin in honey samples based on the study of honey proteins using immunoblot assays. The main goal of our work was to evaluate the use of honey proteins as chemical markers of the floral origin of honey. Considering that honeybee proteins should be common to all types of honey, we decided to verify the usefulness of pollen proteins as floral origin markers in honey. We used polyclonal anti-pollen antibodies raised in rabbits by repeated immunization of Sunflower (Elianthus annuus) and Eucalyptus (Eucalyptus sp.) pollen extracts. The IgG fraction was purified by immunoaffinity. These antibodies were verified with nitrocellulose blotted pollen and unifloral honey protein extracts. The antibodies anti-Sunflower pollen, bound to the 36 and 33 kDa proteins of Sunflower unifloral honey and to honey containing Sunflower pollen; and the antibodies anti-Eucalyptus sp. pollen bound to the 38 kDa proteins of Eucalyptus sp. unifloral honey in immunoblot assays. Satisfactory results were obtained in differentiating between the types of pollen analyzed and between Sunflower honey and Eucalyptus honey with less cross reactivity with other types of honey from different origin and also with good sensitivity in the detection. This immunoblot method opens an interesting field for the development of new antibodies from different plants, which could serve as an alternative or complementary method to the usual melissopalynological analysis to assess honey floral origin.


Assuntos
Eletroforese em Gel de Poliacrilamida , Mel/análise , Immunoblotting , Proteínas de Plantas/análise , Pólen/química , Animais , Anticorpos , Biomarcadores , Eucalyptus/química , Helianthus/química , Imunização , Extratos Vegetais/imunologia , Pólen/imunologia , Coelhos , Sensibilidade e Especificidade
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