4 resultados para revestimento antimicrobiano
em Repositório Institucional da Universidade Tecnológica Federal do Paraná (RIUT)
Resumo:
The use of biopolymers that help to fix pesticides efficiently and degrade easily without harming the environment, and still improve the physiological performance of field soybean seed may bring contributions to the soybean yield. This study aimed to evaluate the effect of cassava starch polymers (AM), sodium alginate (ALG) and polyvinyl alcohol (PVOH), in the concentrations 2, 4 and 6 g / 100 ml of solution, in the physiological attributes of seeds soy, seed speed soaking and performance of soybean seeds after three months of storage. The soybean variety used was the NK 7059 RR. The experimental design used for the three studies was a factorial with 48 experimental units: 3 polymers (AM, ALG and PVOH), 4 different concentrations (0%, 2%, 4% and 6%), with four replications, in a completely randomized design. It was observed the level of significance of the factors and their interactions, applying the test F. The polymers were evaluated by the Tukey test at 5% probability, and the concentrations were evaluated by polynomial regression. The witness obtained better results for most variables studied. Among the polymers, the best coating was observed PVOH because it was the less viscous polymer and visually not served as a substrate for microorganisms. However, also, satisfactory results were obtained for the AM and ALG polymers at a concentration of 2%. There was not interference of the polymers studied with regard to reduction of imbibition rate of soybean seeds. The hydrophilicity of polymers, mainly the AM and ALG accelerated soaking seeds harming germination at concentrations 4% and 6%. In general, the higher the concentration of polymers tended to worse results.
Resumo:
Considering the social and economic importance that the milk has, the objective of this study was to evaluate the incidence and quantifying antimicrobial residues in the food. The samples were collected in dairy industry of southwestern Paraná state and thus they were able to cover all ten municipalities in the region of Pato Branco. The work focused on the development of appropriate models for the identification and quantification of analytes: tetracycline, sulfamethazine, sulfadimethoxine, chloramphenicol and ampicillin, all antimicrobials with health interest. For the calibration procedure and validation of the models was used the Infrared Spectroscopy Fourier Transform associated with chemometric method based on Partial Least Squares regression (PLS - Partial Least Squares). To prepare a work solution antimicrobials, the five analytes of interest were used in increasing doses, namely tetracycline from 0 to 0.60 ppm, sulfamethazine 0 to 0.12 ppm, sulfadimethoxine 0 to 2.40 ppm chloramphenicol 0 1.20 ppm and ampicillin 0 to 1.80 ppm to perform the work with the interest in multiresidues analysis. The performance of the models constructed was evaluated through the figures of merit: mean square error of calibration and cross-validation, correlation coefficients and offset performance ratio. For the purposes of applicability in this work, it is considered that the models generated for Tetracycline, Sulfadimethoxine and Chloramphenicol were considered viable, with the greatest predictive power and efficiency, then were employed to evaluate the quality of raw milk from the region of Pato Branco . Among the analyzed samples by NIR, 70% were in conformity with sanitary legislation, and 5% of these samples had concentrations below the Maximum Residue permitted, and is also satisfactory. However 30% of the sample set showed unsatisfactory results when evaluating the contamination with antimicrobials residues, which is non conformity related to the presence of antimicrobial unauthorized use or concentrations above the permitted limits. With the development of this work can be said that laboratory tests in the food area, using infrared spectroscopy with multivariate calibration was also good, fast in analysis, reduced costs and with minimum generation of laboratory waste. Thus, the alternative method proposed meets the quality concerns and desired efficiency by industrial sectors and society in general.
Resumo:
The Baccharis oreophila Malme belongs to the Asteraceae family. In Brazil are reported 120 species of Baccharis, most located in the South and Southeast regions, the latter presents the highest prevalence, especially in the state of São Paulo. Asteraceae is well known for the production of essential oils, which are liquid, volatile and aromatic substances produced by plants specialized for metabolism possess antibacterial, antifungal, and antioxidant properties. Thus, this study aimed, perform chemical and evaluate the antimicrobial and antioxidant activity of essential oil from dried leaves of B. oreophila collected in winter in Piraquara, Paraná. Obtaining essential oil was given by hydrodistillation in Clevenger apparatus, in triplicate, and the analysis was done using a gas chromatograph coupled to mass spectrometry GC / MS. The identification of the components was made based on retention indices calculated from the co-injection of a series of n-alkanes, followed by comparison of their mass spectra with literature. The antimicrobial activity was assessed by disk diffusion method and microdilution. The antioxidant activity was evaluated by the methods DPPH equivalent Trolox, ABTS and FRAP equivalent Trolox equivalent ferrous sulfate. The essential oil showed 0.47% yield. They identified 57 components (89.38%), 1.51% were classified as hydrogenated monoterpenes, oxygenated monoterpenes 15.14%, 34.84% and 37.87% hydrogenated sesquiterpenes sesquiterpenes oxygenates. As the major components were detected kusimono (16.37%), spathulenol (16.12%), the δ-cadinene (5.68%) and bicyclogermacrene (4.09%). The antimicrobial activity of essential oil was performed for the microorganisms Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Candida albicans ATCC 18804 and Candida tropicalis ATCC 13803, the results showed that the essential oil showed activity against S. aureus Inhibitory Concentration minimum (CIM) 1250 g/mL. In the evaluation of antioxidant activity essential oil showed antioxidant potential for the three methods evaluated, with values of 1,468 m.mol.L-1, 7.126 m.mol.L-1 and 45.515 m.mol.L-1 for ABTS, DPPH and FRAP, respectively. These results demonstrate that the essential oil of B. oreophila showed antimicrobial potential against S. aureus and interesting antioxidant activity, especially for the reducing power of iron ion, demonstrating their potential for future industrial applications. It is important to emphasize that were not observed in the literature reports highlighting such biological properties of B. oreophila oil.
Medidas de concentração de radônio proveniente de argamassas de cimento portland, gesso e fosfogesso
Resumo:
Portland cement being very common construction material has in its composition the natural gypsum. To decrease the costs of manufacturing, the cement industry is substituting the gypsum in its composition by small quantities of phosphogypsum, which is the residue generated by the production of fertilizers and consists essentially of calcium dihydrate and some impurities, such as fluoride, metals in general, and radionuclides. Currently, tons of phosphogypsum are stored in the open air near the fertilizer industries, causing contamination of the environment. The 226 Ra present in these materials, when undergoes radioactive decay, produces the 222Rn gas. This radioactive gas, when inhaled together with its decay products deposited in the lungs, produces the exposure to radiation and can be a potential cause of lung cancer. Thus, the objective of this study was to measure the concentration levels of 222Rn from cylindrical samples of Portland cement, gypsum and phosphogypsum mortar from the state of Paraná, as well as characterizer the material and estimate the radon concentration in an environment of hypothetical dwelling with walls covered by such materials. Experimental setup of 222Rn activity measurements was based on AlphaGUARD detector (Saphymo GmbH). The qualitative and quantitative analysis was performed by gamma spectrometry and EDXRF with Au and Ag targets tubes (AMPTEK), and Mo target (ARTAX) and mechanical testing with x- ray equipment (Gilardoni) and the mechanical press (EMIC). Obtained average values of radon activity from studied materials in the air of containers were of 854 ± 23 Bq/m3, 60,0 ± 7,2 Bq/m3 e 52,9 ± 5,4 Bq/m3 for Portland cement, gypsum and phosphogypsum mortar, respectively. These results extrapolated into the volume of hypothetical dwelling of 36 m3 with the walls covered by such materials were of 3366 ± 91 Bq/m3, 237 ± 28 Bq/m3 e 208 ± 21 Bq/m3for Portland cement, gypsum and phosphogypsum mortar, respectively. Considering the limit of 300 Bq/m3 established by the ICRP, it could be concluded that the use of Portland cement plaster in dwellings is not secure and requires some specific mitigation procedure. Using the results of gamma spectrometry there were calculated the values of radium equivalent activity concentrations (Raeq) for Portland cement, gypsum and phosphogypsum mortar, which were obtained equal to 78,2 ± 0,9 Bq/kg; 58,2 ± 0,9 Bq/kg e 68,2 ± 0,9 Bq/kg, respectively. All values of radium equivalent activity concentrations for studied samples are below the maximum level of 370 Bq/kg. The qualitative and quantitative analysis of EDXRF spectra obtained with studied mortar samples allowed to evaluate quantitate and the elements that constitute the material such as Ca, S, Fe, and others.