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31.
Ricardo Brandes Letícia de Souza Daniel V. F. Vanin Claudimir A. Carminatti Eliana M. Oliveira Regina V. Antônio Derce O. S. Recouvreux 《Fibers and Polymers》2018,19(2):297-306
Bacterial Cellulose (BC) biosynthesized under agitated conditions can produce hydrogels with spherical shapes and the processing parameters govern this formation of BC hydrogels. The variations of these parameters cause different results in the formation of spherical BC and it is relevant to evaluate these effects. Carbon source, inoculum concentration, volume of the culture medium, stirring speed and incubation temperature were the processing parameters evaluated in this work. Therefore, the results obtained were characterized in terms of dry mass production, water uptake and sphericity of the spherical BC. To do so, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were employed as tools for morphological and chemical evaluations. Among the parameters analyzed, the carbon source had the greatest effect on the production of dry mass and water uptake. Glycerol had the greatest growing rate, generating a higher dry mass production with spherical and homogeneous bodies with excellent water absorption indexes. Furthermore, the morphological analysis of BC revealed a typical structure, with high crystallinity index and the presence of typical functional groups. These results indicate a path for the optimized and controlled production of spherical BC, allowing it to be used in many applications, such as enzyme immobilization, water treatment, bone regeneration, spherical cancer model, as adsorption agent and drug delivery. 相似文献
32.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
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Soil microbial activity and crop sustainability in a long-term experiment with three soil-tillage and two crop-rotation systems 总被引:1,自引:0,他引:1
Mariangela Hungria Julio Cezar Franchini Osvaldino Brando-Junior Glaciela Kaschuk Rosinei Aparecida Souza 《Applied soil ecology》2009,42(3):288-296
Reduction in soil disturbance can stimulate soil microbial biomass and improve its metabolic efficiency, resulting in better soil quality, which in turn, can increase crop productivity. In this study we evaluated microbial biomass of C (MB-C) by the fumigation-extraction (FE) or fumigation-incubation (FI) method; microbial biomass of N (MB-N); basal respiration (BR) induced or not with sucrose; metabolic quotient (obtained by the ratio BR/MB-C) induced (qCO2(S)), or not with sucrose (qCO2); and crop productivity in a 14-year experiment in the state of Paraná, southern Brazil. The experiment consisted of three soil-tillage systems [no-tillage (NT), conventional tillage (CT) and no-tillage using a field cultivator every 3 years (FC)] and two cropping systems [a soybean–wheat-crop sequence (CS), and a soybean–wheat–white lupin–maize–black oat–radish crop rotation (CR)]. There were six samplings in the 14th year, starting at the end of the winter crop (wheat in the CS and lupin in the CR plots) and finishing at full flowering of the summer crop (soybean in the CS and maize in the CR). Differences in microbiological parameters were greater than those detected in the total C (TCS) and total N (TNS) contents of the soil organic matter (SOM). Major differences were attributed to tillage, and on average NT was higher than the CT in the following parameters: TCS (19%), TNS (21%), MB-C evaluated by FE (74%) and FI (107%), and MB-N (142%). The sensibility of the microbial community and processes to soil disturbance in the tropics was highlighted, as even a moderate soil disturbance every 3 years (FC) affected microbial parameters but not SOM. The BR was the parameter that most promptly responded to soil disturbance, and strong differences were perceived by the ratio of qCO2 evaluated with samples induced and non-induced with sucrose. At plowing, the qCO2(S):qCO2 was five times higher under CT, indicating a C-starving low-effective microbial population in the C-usage. In general, crop rotation had no effect on microbial parameters or SOM. Grain yield was affected by tillage and N was identified as a limiting nutrient. Linear regressions between grain yields and microbial parameters showed that soybean was benefited from improvements in the microbial biomass and metabolic efficiency, but with no significant effects observed for the maize crop. The results also indicate that the turnover of C and N in microbial communities in tropical soils is rapid, reinforcing the need to minimize soil disturbance and to balance inputs of N and C. 相似文献
36.
Medium Light and Medium Roast Paper-Filtered Coffee Increased Antioxidant Capacity in Healthy Volunteers: Results of a Randomized Trial 总被引:1,自引:1,他引:0
TA Corrêa MP Monteiro TM Mendes DM Oliveira MM Rogero CI Benites CG Vinagre BM Mioto D Tarasoutchi VL Tuda LA César EA Torres 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):277-282
We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482?±?61?ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids-(CGA; 334?mg/150?mL) and less caffeine (231?mg/150?ml) than MR had (210 and 244?mg/150?ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26?% in TAS, 13 and 13?% in CAT, 52 and 75?% in SOD, and 62 and 49?% in GPx after MLR and MR consumption (P?0.001), respectively. ORAC increased after MLR (P?=?0.004). No significant alteration in lipid peroxidation biomarkers was observed. Both coffees had antioxidant effects. Although MLR contained more CGA, there were similar antioxidant effects between the treatments. MRP may have contributed as an antioxidant. These effects may be important in protecting biological systems and reducing the risk of diseases related to oxidative stress. 相似文献
37.
Letícia Aparecida de Moraes Julio Massaharu Marubayashi Valdir Atsushi Yuki Murad Ghanim Vinicius Henrique Bello Bruno Rossitto De Marchi Leonardo da Fonseca Barbosa Laura M. Boykin Renate Krause-Sakate Marcelo Agenor Pavan 《Phytoparasitica》2017,45(4):517-525
In Brazil, the first major invasion event of Bemisia tabaci was that of Middle East–Asia Minor 1 (MEAM1) species, formerly termed as B biotype, which commenced in the 1990s mainly by ornamental plants in São Paulo State. More than two decades after this invasion, the presence of the Mediterranean (MED) species of B. tabaci, formerly Q biotype, was reported in Rio Grande do Sul, the southernmost State of Brazil, and now in São Paulo and Paraná States, in southeastern Brazil. Specimens of whiteflies collected from commercial begonia, hydrangea, petunia and poinsettia greenhouses in São Paulo, and also from begonias and poinsettias collected in flower shops in Paraná, were all identified as belonging to MED species. Furthermore, the secondary endosymbionts Arsenophonus, Hamiltonella and Rickettsia of MED from São Paulo and Paraná were detected by PCR and their presence confirmed by sequencing and FISH analysis, and those results differed from MED detected in Rio Grande do Sul that harbored only Hamiltonella and Cardinium. Our results suggest a new MED invasion into Brazil and is associated with ornamental plants. The two MED populations are genetically different and suggest that they are separate invasions. 相似文献
38.
C. Eliana Gattullo Andreina Traversa Nicola Senesi Elisabetta Loffredo 《Water, air, and soil pollution》2012,223(9):6035-6044
The objective of this study was to assess the removal of the endocrine disruptor 4-nonylphenol (NP) at a concentration of 1?mg?L?1 by ryegrass and radish during germination and growth. The decontamination process was evaluated in water only or in water containing two organic fractions, a soil humic acid (HA) and a river natural organic matter (NOM) at concentrations of 10 and 200?mg?L?1. The addition of these fractions aimed to simulate the organic content of real aqueous systems. At the end of germination and growth, residual NP was measured by chromatographic analysis. Also, NP phytotoxicity was evaluated during germination. In germination experiments, NP in water only was not toxic for ryegrass and radish which removed, respectively, 37 and 51?% of the initial NP added. In water added with HA or NOM at both doses, in general, NP did not influence or inhibited seed germination. Both doses of HA in water promoted the removal of NP by germinating seeds, whereas NOM exerted differentiated results in the two species as a function of the dose applied. After 2?days of growth, in all treatments both species almost completely removed NP and accumulated a very little fraction of product. This study demonstrated that both ryegrass and radish possess a relevant capacity to remove the endocrine disruptor NP from water also in the presence of different organic fractions, thus suggesting their use in the decontamination of real aquatic systems. 相似文献
39.
Custódio L Escapa AL Fernandes E Fajardo A Aligué R Alberício F Neng N Nogueira JM Romano A 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(1):78-84
This work aimed to evaluate the phytochemical content and to determine the antioxidant and cytotoxic activities of methanol
extracts of the carob tree (Ceratonia siliqua L.) germ flour. The extracts were rich in phenolic compounds, had considerable antioxidant activity, and reduced the viability
of cervical (HeLa) cancer cells. The chemical content and the biological activities of the extracts were significantly affected
by gender and cultivar. Female cultivar Galhosa had the highest levels of phenolic compounds, and the highest antioxidant
activity. Extracts from the hermaphrodite trees and from the female cultivars Galhosa and Costela/Canela exhibited the highest
cytotoxic activity. The most abundant compound was theophylline. The phenolic content was correlated to both antioxidant and
cytotoxic activities. Our findings provide new knowledge about the health implications of consuming food supplemented with
carob germ flour. 相似文献
40.
Eliana L. Tassi Francesca Pedron Meri Barbafieri 《Water, air, and soil pollution》2011,216(1-4):275-287
Assessment of native plants and laboratory-scale phytoextraction tests are fundamental and preliminary steps in checking the feasibility and practice of low-cost and low-impact phytoremediation. In this study, we investigated the absorption of B by plants as a tool to remove boron in sediments from different areas of the Cecina River basin in Tuscany, Italy. The investigation was performed analyzing total and available B fraction in sediment samples as well as the B content in different tissues of native plants colonizing the contaminated areas. In laboratory scale, a phytoextraction screening test was performed. Selected high biomass crops (Brassica juncea, Zea mays, and Helianthus annuus) were evaluated in the most contaminated sample in two consecutive growing cycles. Results from field survey showed no hyperaccumulator native plant was present in the investigated areas although, high accumulation levels were found in native species from Bulera dump (Rumex crispus??259 mg?kg?1 and Poa spp??203 mg?kg?1). Results from laboratory phytoextraction tests showed a higher ability of B. juncea which removed about 18.5 mg?B?kg?1 sediment in after the two consecutive growing cycles, representing on the whole 45% of the initial available B fraction. The sediment characteristics affected by the phytoextraction processes were also discussed. 相似文献