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Rapid methods to determine the physiological quality of seeds are demands of the productive chain of this sector, in order to identify lots of low germinative potential already in its reception and/or processing. Thus, the objective was to investigate the pH test of exudate to estimate the viability of wheat seeds and to verify if it has a correlation with the standard germination test by the correlation with the germination test. It was used 10 lots of wheat seeds, from three cultivars, evaluated for the initial quality by determining the water content and viability by the germination test. The pH test of exudate was conducted with four repetitions of 50 seeds, soaked in individual cells containing 1.5 mL of deionized water, in the periods of two, three and four hours, at 20, 25 and 30 °C. After each period, a drop of indicator solution phenolphthalein was added and read the results according to the staining of the exudate present in each cell. For greater reliability, after reading the results of each tested combination, the seeds were placed to germinate. Low correlation of the exudate pH test with germination was verified for wheat, in all tested combinations, even exhibiting negative coefficients depending on the temperature/soaking period used. It can be inferred that the pH test of exudate is not efficient for a quick evaluation of the viability of wheat seeds. [ABSTRACT FROM AUTHOR]

Recently, fish byproducts have been appraised as a source of structurally diverse bioactive compounds. In this context, fish mucus has revealed a myriad of pharmacological activities. This study describes a new bioactive molecule release system composed of protein nanoparticles from pacamã (Lophiosilurus alexandri) mucus, an endemic fish to the São Francisco River (Brazil). The process of obtaining and applying these nanoparticles, composed of proteins present in the pacamã mucus, as biocompatible carriers of bioactive molecules is also addressed herein. Therefore, the external mucus of the fish was collected, lyophilized and hydrated in deionized water containing the template molecule. After pH adjustment to 7.5, followed by sonication and centrifugation, the formed nanoparticles were collected in the supernatant. Additionally, the mucus and the particles were characterized, and pharmacological effects were evaluated regarding their antifungal, antibacterial, anticancer, anti or pro-inflammatory and antinociceptive proprieties. NP-Mucus did not exhibit antibacterial activity against Pseudomonas aeruginosa or Staphylococcus aureus. However, it showed potential effects against Candida albicans with a minimum inhibitory concentration (MIC) of 1 µg/mL, and significant pro-inflammatory role, reflected by cellular recruitment activity and healing effects. Therefore, future studies are now needed in order to identify specific compounds in NP-mucus responsible for the observed effects in order to provide new pharmacological and therapeutic strategies. [ABSTRACT FROM AUTHOR]

This work proposes a new method for the determination of phenanthrene (FEN) in aqueous medium with a cobalt phthalocyanine modified glassy carbon electrode (ECV / CoPc), using Differential Pulse Voltammetry (VPD), whose oxidation of FEN occurs between 1,3 and 1,4 V. The electrode was modified with a 1x10-3 mol∙L-1 CoPc methanolic solution containing 10% Nafion. For voltammetric measurements in Differential Pulse mode, an amplitude of 0.7V and a scan rate of 0.04V s-1 were used. Experimental parameters were optimized for the purpose of determination of FEN in groundwater collected in a water well of a São Luis-MA fuel station. Under these optimized conditions, an analytical curve was obtained in the 0.49 to 2,4 μM concentration range, with a detection limit of 1,2 x 10-10 mol∙L-1. The method was applied to a real groundwater sample from a water well located at a fuel station, and an average concentration of 0.037 μM FEN was found (n = 5), presenting a variation coefficient of 0.88, indicating good precision. Accuracy was assessed by the recovery test, whose average value was 99.9%. These results indicate that the proposed procedure is a good alternative for the analysis of FEN in natural water. [ABSTRACT FROM AUTHOR]

The objective of the present study was to use the bootstrap method to construct confidence intervals for limit detection in radiochemical studies. For that, a computer program was developed in the C ++ language that was called boot limit. To test the boot limit, the concentration of 210Pb under background conditions (white) was determined using the ion exchange resin method in deionized water samples. In this case, the limit of detection ranged from 26.7 to 140.7 mBq.L-1, with a mean of 70.34 mB.L-1. The results showed that the bootstrap method is a very efficient statistical tool to construct confidence intervals in determining the limit of detection in radiochemistry. [ABSTRACT FROM AUTHOR]

The germination process begins with the imbibition, during the available water, which triggers a sequence of metabolic changes that culminate in the protrusion of the primary root into viable seeds. By the organization of the cell membrane system, a method that can indicate the level of seed vigor is the conductivity. The objective of this study was to evaluate and model the process of imbibition of chickpea seeds, in addition to establishing an efficient methodology for water volume, imbibition time and number of seeds in the electric conductivity test. Eight lots were used, four of the BRS Aleppo cultivar and four of the Cícero cultivar, which were submitted to the germination and vigor test for initial characterization. The electrical conductivity was conducted with 50 and 75 seed subsamples using 75 and 100 mL of deionized water, and the periods 2, 4, 8, 12, 18, 24 and 30 h were maintained at 25 °C. The experiment of electrical conductivity was in a completely randomized design with four replicates. The Peleg model was adjusted for imbibition kinetics. The most appropriate methodology was the use of 75 seeds, volume of 100 mL of water for 30 h. The Peleg model was efficient in describing the process of water absorption, although there were differences in the physiological potential of the lots. [ABSTRACT FROM AUTHOR]

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The purification of water used in laboratories and healthcare facilities should be performed by different methods, depending on your purpose. The presence of micro-organisms is allowed on the same, provided they are within the limits specified in legislation and are not pathogenic. Thus, this study evaluated the quality of water from scrubbers equipment (distillators and deionizeds) agents forming biofilms. Also examined were interfering factors (hose, resin and water supply equipment) and sanitizing ozone action on micro-organisms isolated. Pseudomonas were investigated, mesophilics aerobics (AM) and filamentous fungi and yeasts (FFY). It was found that all water samples showed deionizeds quantification AM outside the recommended standards. Additionally, 60% of the samples had FYF and Pseudomonas aeruginosa. Only one sample of distilled water (stored for more than 24 hours) showed values of AM > 10 CFU/ml, and P. aeruginosa. Resins were detected AM (m=1,75×102CFU/cm²), P. aeruginosa (m=2,03×102CFU/100cm²) and FFY (m=2,5×101CFU/cm²). We found high amounts of AM (m =7,0×101CFU/cm²), FFY (m=2,5×103CFU/cm²) and P. aeruginosa (m=1,0 ×103CFU/100cm²) in 66,67% of the hoses from the distillators. There was water contamination after the purification process (passing through resin), mainly in deionizeds, since the analysis of water quality that was supplied to the extent permitted by law. As for the micro-organisms isolated, ozone was able to decrease 9 cycles log in 5 seconds. Therefore, the use of ozonated and purified water becomes an attractive option as sanitizing and practical alternative. [ABSTRACT FROM AUTHOR]