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The determination of Cd, Co, Cr, Cu, Fe, Na, Zn, and Pb by inductively coupled plasma-optical emission spectrometry (ICP OES) was performed on dry matter and decoctions of the medicinal plants Cordia salicifolia, Chiococca alba (L.) Hitchc., and Echites peltata used as an appetite suppressant and diuretic in Brazil. The accuracy of the measurements was analyzed by the spike recovery test. Results showed that the concentration of these seven metals (Cd, Co, Cr, Cu, Fe, Na, and Zn) in dry plant samples is below the oral concentration of elemental impurities established by the United States Pharmacopoeia Convention (USP). However, there are no concentration limits for Fe, Na, and Zn established by the USP in drug substances and excipients. Levels higher than the recommended value by the USP were observed for Pb and the lowest for Cd, Co, Cr, and Cu, both in dried plant samples and their decoctions. In the decoctions prepared from these plants were found elements such as Cd, Co, Cr, Cu, Fe, Na, Zn, and Pb. In the decoction prepared from 40 g C. salicifolia leaves and 40 g C. alba wood, the content of Cd is above the oral daily exposure value set by the USP. Hazard index (HI) for decoctions prepared from these plants exceeded the threshold (1). Given the uncertainties associated with the estimates of toxicity values and exposure factors, futures researches should address the possible toxicity in humans. Uncontrolled selling and long-term ingestion of medicinal plants can cause toxicity and interfere with the effect of drugs. Limited knowledge on the interaction potential of medicinal plants poses a challenge and public health problem in Brazil and other countries.

Several species of Arecaceae are widely distributed in tropical regions and are economically important as a source of vegetable oil and bioactive nutrients beneficial to health and human nutrition. In this work, the physical and chemical characteristics of the oils and fruits from Syagrus romanzoffiana, Attalea phalerata, Mauritia flexuosa and for the first time for Attalea dubia (Mart.) Burret were determined. All fruits were dimensioned according to the biometric analysis (size and mass). Nutritional analysis showed high levels of lipids, proteins, sugars and fibers, as well as Ca, Mg, K, Cu, Mn, Fe and Zn minerals. The composition of fatty acids showed the predominance of short and unsaturated fatty acids carbon chain. All fruits presented high content of polyphenols and carotenoids (except for S. romanzoffiana). Moreover, all fruits demonstrate antioxidant activity by direct capture of free radicals ABTS and DPPH. Finally, our results demonstrate that these fruits have a relevant concentration of nutrients and bioactive compounds with importance for human health. Such data open up promising prospects for the scientific exploration and use of these fruits as an alternative source to combat malnutrition as well as to compose formulations of food products with functional properties. Finally, our results demonstrate that these fruits present a relevant concentration of nutrients and bioactive compounds with importance for human health, with promising perspectives for the scientific exploration and use of these fruits as an alternative source to avoid malnutrition as well as to compose formulations of food products with functional properties.

Metals are chemical contaminants that are not normally biodegradable and accumulate in living organisms. In addition, they may present toxic effects to plants and affect human health causing mutations and adn damage of exposed organisms. The objective of this study was to evaluate the cytotoxicity, genotoxicity and mutagenicity of the aluminum, manganese and lead using A.cepa test. Solutions in three concentrations with the metals and controls were prepared for the genetic analyzes. The seeds of A. cepa were exposed to germination, and evaluation of cytotoxicity, genotoxicity and mutagenicity. The results showed that the concentrations of the metals did not interfere in the growth of the radicle, but the increase in the concentration of the metals was directly proportional to the increase of the number of seeds germinated. For the mitotic index it was observed that the increase in Al concentration provided the increase of cells in cell division, but for Mn and Pb there was reduction. The metals at the concentrations evaluated did not present genotoxic and mutagenic potential for meristematic cells of A. cepa. The A. cepa test it showed to be effective for performed analyzes, however, further studies are needed using other biological assays. DOI: http://dx.doi.org/10.17807/orbital.v10i1.1037

Oxygen reduction reaction (ORR) is greatly affected by the morphology as well as the elemental composition of the nitrogen-doped carbon-based electrocatalysts. Thus, this work focuses on: (i) nitrogen doping of different graphene-based materials (two-dimensional materials: chemically converted graphene, graphene oxide, and commercially available graphene, and one-dimensional material: graphene nanoribbons) that differ from each other by morphology as well as elemental composition and (ii) studying the ORR performance of these N-doped carbonaceous catalysts in alkaline medium. The nitrogen doping is achieved by low-cost synthetic method based on hydrothermal treatment at mild conditions. The results indicate that: (i) nitrogen doping is dependent on the carbonaceous substrate used and (ii) these N-doped graphene-based catalysts vary drastically by the electrocatalytic activity for ORR as well as the selectivity for HO2− and OH− production in alkaline medium. Roughly, predominantly HO 2 − was produced on two-dimensional graphene-based catalysts enriched with low nitrogen content (0.9–1.4 at.%) and mostly OH− was formed on graphene nanoribbons as one-dimensional catalyst containing low amount of nitrogen (2.1 at.%). This work is valuable for giving further insights into the ORR performance on N-doped graphene-based nanocarbons.

Influence of different foliar fertilizers (phosphite, micronutrients, biostimulant, phosphite + micronutrients, phosphite + biostimulant, micronutrients + biostimulant and phosphite + micronutrients + biostimulant) on yield of sugarcane was evaluated after fertilization at 30, 90 and 150 days after harvesting two-year-old sugarcane. The experiment was carried out in a commercial crop employing a randomized block design in four replicates. Higher stalk masses were observed for fertilization at 30 days after harvest, and the higher content of sucrose, total recoverable sugar and Brix degrees were observed for sugarcane fertilized after 150 days. Statistical analysis (Duncan's test) revealed no significant variation (P < 0.05) in Brix degree, sucrose content and total recoverable sugar. For total recoverable sugar x stalk weight (the main payment type for sugarcane producers), the following sequence (time treatment, fertilizer composition) 30-days, micronutrient + biostimulant; 150-days, biostimulant; and 90...

Made available in DSpace on 2022-04-28T22:37:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-01 The usefulness of the side pixel registration approach and molecular absorption was investigated for the determination of phosphorus (P) and potassium (K) in liquid fertilizers by highresolution continuum source flame atomic absorption spectrometry. The phosphorus oxide (PO) lines at 246.400 nm, 247.620 nm, 247.780 nm, 324.616 nm, and 327.040 nm were evaluated. The influence of side pixel registration to extend the linear working range was also investigated by measuring at wings (404.402 nm, 404.406 nm, 404.410 nm, 404.418 nm, 404.422 nm and 404.426 nm) of the secondary line for K at 404.414 nm. For the lines 327.040 nm and 404.422 nm, analytical curves in the 100-5000 mg L.1 P and 50-1000 mg L-1 K ranges were obtained with linear correlations better than 0.999 and 0.995, respectively. The proposed method was applied to six liquid fertilizer samples. The found concentrations for K and P were in agreement with those obtained by inductively coupled plasma optical emission spectrometry (ICP-OES), spectrophotometry, and flame atomic emission spectrometry at the 95% confidence level. UNESP University Estadual Paulista Analytical Chemistry Department, Rua Prof. Francisco Degni, s/n, 14801-970, Araraquara - SP UNESP University Estadual Paulista Analytical Chemistry Department, Rua Prof. Francisco Degni, s/n, 14801-970, Araraquara - SP

A direct immersion solid-phase microextraction coupled with gas chromatography-electron capture detection (SPME-GC-ECD) method was optimized and validated for the quantitative determination of 18 organochlorine pesticides in ground water. Ionic strength, stirring speed, adsorption and desorption time and pH were some of the parameters investigated in order to select the optimum conditions for SPME with a 50/30 DVB/CAR/PDMS fiber coating. The SPME-GC/ECD method showed good linear response below 10 ng L(-1) with R(2) values in the range of 0.9950-0.9997. The repeatability of the measurements were lower than 10%. Values of relative recoveries located within the acceptable range (80-120%). Limits of quantification (LOQ) from 4.5x10(-3) to 1.5 ng L(-1) were obtained. On average 8 organochlorines were found per sample, even so all the 18 organochlorines were quantified among them. Substances such as endrin ketone, gamma-BHC and beta-BHC were the pesticides determined in larger concentration (0.06-305 ng L(-1)), while methoxychlor and aldrin in smaller amounts (0.151-1.55 ng L(-1)). Measured levels of organochlorine pesticides were above the limits established by Brazilian regulations.

Made available in DSpace on 2022-04-30T07:05:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-01 A simple and rugged method to determine Ca, K and Mg in a single aliquot of medicinal plants by high-resolution continuum source flame atomic absorption spectrometry is proposed. Secondary lines for Ca (239.856 nm) and K (404.414 nm), and the alternate line measured at wing of the secondary line for Mg at 202.588 nm allowed calibration within the 20 - 500 mg L-1 Ca and K, and 1.0 - 80 mg L-1 Mg. Twenty samples and three plant certified materials were analyzed. Results were in agreement at a 95% confidence level with reference values. Limits of detection were 2.4 mg L-1 Ca, 1.9 mg L-1 K and 0.3 mg L-1 Mg. The RSD (n=12) were ≤ 5.1% and recoveries were between 83 and 108% for all analytes. Instituto de Química Universidade Estadual Paulista, CP 355 Faculdade de Ciências Exatas e Tecnologia Universidade Federal da Grande Dourados, CP 533 Instituto de Química Universidade Estadual Paulista, CP 355

Concentrations of Fe, Mn, Co, Cr, Zn and Cu were determinated using flame atomic absorption spectrometry in nine lichen species of the Sul-Mato-Grossense cerrado. The average metal ion concentrations varied in the following ranges: Fe, 248.41-1568.01; Mn, 98.50-397.33; Co, 10.08-24.81; Cr, 18.24-44.26; Zn, 14.62-34.79 and Cu, 3.23-7.57 mg kg-1. Statistical analysis (Pearson and Cluster) applied to the metal ion concentrations indicated that the accumulation of these ions can be due to several anthropogenic sources including agricultural activities, mineral exploration, biomass burning, soil mineral composition and leather tanning processes by chromium.

The essential oil obtained from the stem bark of Croton urucurana Baillon (Euphorbiaceae) was analysed by GC and GC-MS. 83 compounds were identified and borneol (14.7%), bornyl acetate (5.2%), 1-isopropyl-7-methyl-4-methylene-1,3,4,5,6,8-hexahydro-2H-naphthalen-4a-ol (14.7%), sesquicineole (10.5%) and gamma-gurjunene epoxide (5.4%) were the main components. The EC50 value of the crude essential oil in the DPPH free radical scavenging assay was 3.21 mg mL-1. The fraction of the crude essential oil that presented antioxidant activity was purified by prep-TLC on silica gel. GC and GC-MS analysis revealed that alpha-bisabolol (38.3%), alpha-eudesmol (9.3%) and guaiol (8.2%) were the main components of the antioxidant fraction. The EC50 value measured for the bioactive oil fraction in the DPPH assay was 1.05 mg mL-1. The antimicrobial activity of the crude essential oil was assayed against seven Gram-positive and Gram-negative bacteria and three yeasts. Measured MIC values ranged from 1.25 to 10.00 mg mL-1. O óleo essencial obtido a partir das cascas do caule de Croton urucurana Baillon (Euphorbiaceae) foi analisado por CG e CG-EM. 83 compostos foram identificados, sendo borneol (14,7%), acetato de bornila (5,2%), 1-isopropil-7-metil-4-metileno-1,3,4,5,6,8-hexaidro -2H-naftalen-4a-ol (14,7%), sesquicineol (10,5%) e epóxido de gama-gurjuneno (5,4%) os principais componentes. Para o óleo essencial bruto, foi determinada em 3,21 mg mL-1 a EC50 no ensaio de atividade antioxidante frente ao radical livre DPPH. A fração do óleo essencial bruto que apresentou atividade antioxidante foi purificada por CCD sobre sílica gel. Análises de CG e CG-EM revelaram que alfa-bisabolol (38,3%), alfa-eudesmol (9,3%) e guaiol (8,2%) são os principais componentes da fração antioxidante. A EC50 medida no teste frente ao DPPH foi de 1,05 mg mL-1 para a fração bioativa. Foi determinada a atividade antimicrobiana do óleo essencial bruto frente a sete bactérias Gram-positivas e Gram-negativas e três fungos. Os valores de CIM medidos variaram de 1,25 a 10,00 mg mL-1.