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São Carlos, Brazil

Amais R.S.,Federal University of Sao Carlos | Garcia E.E.,State University of Maringa | Monteiro M.R.,Sao Paulo State University | Nogueira A.R.A.,Embrapa Pecuaria Sudeste | Nobrega J.A.,Federal University of Sao Carlos
Microchemical Journal | Year: 2010

An analytical procedure for direct introduction of biodiesel samples into an inductively coupled plasma mass spectrometer (ICP-MS) by using microemulsion for sample preparation was developed here. Cadmium, Co, Cu, Mn, Ni, Pb, Ti, and Zn were determined in biodiesel microemulsified samples prepared from different oleaginous sources (African palm, castor beans, palm, soybeans and an unknown oleaginous). Microemulsions were prepared using 0.25mL Triton X-100, 0.25mL 20% vv-1 HNO3, 0.50mL biodiesel sample and 4.0mL n-propanol. Argon-oxygen mixture was added to the plasma as auxiliary gas for correcting matrix effects caused by the high carbon load due to biodiesel microemulsions. The oxygen gas flow rate was set in 37.5mLmin-1. The accuracy of the developed procedure was evaluated by applying addition-recovery experiments for biodiesel samples from different sources. Recoveries varied from 76.5 to 116.2% for all analytes but Zn in castor beans biodiesel sample (65.0 to 76.2%). Recoveries lower than 86.6% were obtained for palm biodiesel sample, probably due to matrix effects. Detection limits calculated by using oxygen in the composition of the auxiliary gas added to the plasma were higher than those calculated without using it, probably due to the highest formation of oxides. Despite oxides formation, best analytical performance was reached by using oxygen as auxiliary gas and by proper correction of transport interferences. The developed procedure based on microemulsion formation was suitable for direct introduction of biodiesel samples in ICP-MS. © 2010 Elsevier B.V.

Palhares J.C.P.,Embrapa Pecuaria Sudeste
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The study aims to calculate the water footprint of swines slaughter in Santa Catarina State in the decade of 2001-2011, and to evaluate the impact of nutritional strategies in the value of blue and gray water footprint. Five different nutritional strategies were assessed: T1, conventional diet, T2, diet with amino acids, T3, diet with phytase, T4, diet with organic minerals, T5, diet with the technologies (T2, T3 and T4). The values of water footprint showed increasing pattern over the decade, due to an increase in the number of animals slaughtered. Conventional diet had the highest value and the diet with three strategies the lowest. The reduction was 18% among these treatments. The highest value to gray water footprint was found for conventional diet (15, 073 m3 year-1) and lowest for strategy with phytase (11, 307 m3 year-1). For each liter of water used 179 kcal in T1, 200 kcal in T2, 193 kcal in T3, 200 kcal in T4, and 218 kcal in T5 were generated. The macro-region West accounted for 75 to 77% of the total water footprint for a given year and the South macro-region for 9 to 12%. The results support that the use of nutritional strategies provide a swine production more conservationist in water use, reducing their blue and grey water footprints.

Nobrega J.A.,Federal University of Sao Carlos | Pirola C.,Milestone S.r.l. | Fialho L.L.,Federal University of Sao Carlos | Rota G.,Milestone S.r.l. | And 2 more authors.
Talanta | Year: 2012

Advancements in sample preparation for performing trace analysis of inorganic analytes are coming from the dissemination of microwave-assisted procedures, but there is still room for improvements by looking for simple and easily applied procedures. Recently it was proposed a new approach called single reaction chamber with capability for digestions at high pressures and temperatures using simple vials and racks. This was a limitation of former cavity microwave ovens with closed vessels. It was demonstrated here that the use of single reaction chamber approach allows the implementation of efficient digestions using diluted solutions of nitric acid and also allows addressing a critical need of sample preparation for inorganic analysis by running mixed batches of samples. The feasibility of this procedure was demonstrated for organic samples and accuracy was proved by using certified reference materials of apple leaves, bovine liver and whole milk powder. Digestions performed of whole milk powder and bovine liver using 2.0 mol L-1 nitric acid solution plus concentrated hydrogen peroxide at 240°C led to residual carbon contents of 0.825 and 1.50% and residual acidities of 1.04 and 0.618 mol L -1, respectively. These parameters are fully compatible with further measurements using ICP OES or ICP-MS. Al, Cu, Fe, Mn, Mo, Rb, Se, Sr, and Zn were accurately determined by ICP OES or ICP-MS depending on their concentrations in digests. © 2012 Elsevier B.V. All rights reserved.

The effects of calving year and season, property, sex of the calf, feeding regime, age of calf and age of dam at calving, maternal and direct additive effects of Charolais breed, and maternal heterosis effects among Charolais and zebu breeds were evaluated by the method of least squares on economical importance traits such as weight, scrotal circumference and visual scores for slaughter conformation, navel score and hair coat at weaning of the Canchim breed. Data from 12,334 Canchim calves born from 1999 to 2005 were used. Calving year and season, property, feeding regime and age of dam (linear and quadratic) had significant effects on all the studied characteristics. There were effects of sex on weaning weight and navel score; of age of the calf on weight, scrotal circumference and slaughter conformation and hair coat scores; and of proportion of Charolais on the calf and on the dam on weaning weight, and on scores of slaughter conformation and hair coat; and of maternal heterozygose on weight, scrotal circumference, slaughter conformation and navel scores. Additive direct effects of the Charolais as deviation of zebu were negative on weight, slaughter conformation and hair coat score at weaning, while the maternal additive effects were positive. Maternal heterotic effects were positive on weight, scrotal circumference, slaughter conformation and navel scores. In general, these sources of variation have to be taken into account on estimates of genetic parameters and on genetic evaluations of Canchim animals for the studied characteristics. © 2011 Sociedade Brasileira de Zootecnia.

Katiki L.M.,Institute Zootecnia SAA APTA | Ferreira J.F.S.,U.S. Department of Agriculture | Gonzalez J.M.,U.S. Department of Agriculture | Zajac A.M.,Virginia Polytechnic Institute and State University | And 3 more authors.
Veterinary Parasitology | Year: 2013

Although tannin-rich forages are known to increase protein uptake and to reduce gastrointestinal nematode infections in grazing ruminants, most published research involves forages with condensed tannins (CT), while published literature lacks information on the anthelmintic capacity, nutritional benefits, and antioxidant capacity of alternative forages containing hydrolyzable tannins (HT). We evaluated the anthelmintic activity and the antioxidant capacity of plant extracts containing either mostly CT, mostly HT, or both CT and HT. Extracts were prepared with 70% acetone, lyophilized, redissolved to doses ranging from 1.0mg/mL to 25mg/mL, and tested against adult Caenorhabditis elegans as a test model. The extract concentrations that killed 50% (LC50) or 90% (LC90) of the nematodes in 24h were determined and compared to the veterinary anthelmintic levamisole (8mg/mL). Extracts were quantified for CT by the acid butanol assay, for HT (based on gallic acid and ellagic acid) by high-performance liquid chromatography (HPLC) and total phenolics, and for their antioxidant activity by the oxygen radical absorbance capacity (ORAC) assay. Extracts with mostly CT were Lespedeza cuneata, Salix X sepulcralis, and Robinia pseudoacacia. Extracts rich in HT were Acer rubrum, Rosa multiflora, and Quercus alba, while Rhus typhina had both HT and CT. The extracts with the lowest LC50 and LC90 concentrations, respectively, in the C. elegans assay were Q. alba (0.75 and 1.06mg/mL), R. typhina collected in 2007 (0.65 and 2.74mg/mL), A. rubrum (1.03 and 5.54mg/mL), and R. multiflora (2.14 and 8.70mg/mL). At the doses of 20 and 25mg/mL, HT-rich, or both CT- and HT-rich, extracts were significantly more lethal to adult C. elegans than extracts containing only CT. All extracts were high in antioxidant capacity, with ORAC values ranging from 1800μmoles to 4651μmoles of trolox equivalents/g, but ORAC did not correlate with anthelmintic activity. The total phenolics test had a positive and highly significant (r=0.826, p≤0.01) correlation with total hydrolyzable tannins. Plants used in this research are naturalized to the Appalachian edaphoclimatic conditions, but occur in temperate climate areas worldwide. They represent a rich, renewable, and unexplored source of tannins and antioxidants for grazing ruminants, whereas conventional CT-rich forages, such as L. cuneata, may be hard to establish and adapt to areas with temperate climate. Due to their high in vitro anthelmintic activity, antioxidant capacity, and their adaptability to non-arable lands, Q. alba, R. typhina, A. rubrum, and R. multiflora have a high potential to improve the health of grazing animals and must have their anthelmintic effects confirmed in vivo in both sheep and goats. © 2012.

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