This work reports the development of a certified reference material (CRM) of holmium(III) oxide Ho2O3 in acidic solution for the wavelength scale calibration of UV-Vis spectrophotometers. A 4.0% Ho2O3 solution was gravimetrically prepared in 10% perchloric acid and bottled in 5.0 mL glass ampoules. Homogeneity, stability and characterization were assessed according to ISO 17034 and ISO Guide 35. The material certification was undertaken by two laboratories by using UV-Vis spectrophotometry for characterization of the 14 peaks of minimum transmittance of Ho2O3, using a spectral bandwidth of 1.00 nm and a scanning speed of 30.0 nm min‒1. The material property values in wavelength (nm) were obtained for these 14 peaks, together with the expanded uncertainty (U) of 0.12 nm, for a coverage factor (k = 2.00) corresponding to a probability of approximately 95%, which took into account the standard uncertainties obtained in each study performed for the certification of the produced reference material.

ABSTRACT In general, Passiflora species have been reported for their folk medicinal use as sedative and anti-inflammatory. However, P. caerulea has already been reported to treat pulmonary diseases. Severe pulmonary tuberculosis, generally caused by Mycobacterium tuberculosis strains resistant to multiple drugs, can lead to deleterious inflammation and high mortality, encouraging new approaches in drug discovery. Thus, the aim of this work was to evaluate the Passiflora mucronata Lam., Passifloraceae, potential for tuberculosis treatment. Specifically, related to antimycobacterial activity and anti-inflammatory related effects (based on inhibition of nitric oxide, tumor necrosis factor-alpha production and antioxidant potential), as well as the chemical profile of P. mucronata. High performance liquid chromatography coupled with diode-array ultraviolet and mass spectrometer analyses of crude hydroalcoholic extract and ethyl acetate fraction showed the presence of flavonoids. Ethyl acetate fraction showed to be as antioxidant as Ginkgo biloba standard extract with EC50 of 14.61 ± 1.25 µg/ml. One major flavonoid isolated from ethyl acetate fraction was characterized as isoorientin. The hexane fraction and its main isolated compound, the triterpene β-amyrin, exhibited significant growth inhibitory activity against Mycobacterium bovis BCG (MIC50 1.61 ± 1.43 and 3.93 ± 1.05 µg/ml, respectively). In addition, Passiflora mucronata samples, specially hexane and dichloromethane fractions, as well as pure β-amyrin, showed a dose-related inhibition of lipopolysaccharide (LPS)-induced nitric oxide production. In conclusion, Passiflora mucronata presented relevant biological potential and should be considered for further studies using in vivo pulmonary tuberculosis model.

A população de plantas e a adubação com micronutrientes influenciam diretamente o comportamento do feijão-caupi(Vigna unguiculata (L.) Walp.), e dependem das condições de plantação, das características morfológicas e fisiológicas e da capacidade produtiva das cultivares, resultando, assim, na produção de sementes de alta qualidade. Nesse sentido, o objetivo deste trabalho foi verificar os efeitos de doses de molibdénio e densidades de plantas na produção e qualidade de sementes de feijão-caupi, cultivar BRS Novaera. O delineamento experimental foi em blocos casualizados, com quatro repetições, sendo os tratamentos dispostos em esquema fatorial 4 x 4, envolvendo quatro doses de molibdénio aplicadas via semente (0, 40, 80 e 120 g.ha-1) e quatro densidades populacionais (100, 160, 220 e 280 mil plantas.ha-1). Após a colheita, determinou-se a produtividade e as sementes foram submetidas às seguintes avaliações: teor de humidade, massa de mil sementes, germinação, emergência de plântulas, índice de velocidade de emergência, comprimento e massa seca da parte aérea de plântulas. A aplicação de doses de molibdénio via sementes não afetou a produção e a qualidade das sementes da cultivar. Entretanto, o aumento da densidade de plantas por hectare promoveu acréscimos significativos na produtividade e na massa de mil sementes.

The plant population density and fertilization with micronutrients directly influence the cowpea Vigna unguiculata (L.) Walp. performance, depending on the growing conditions, the morphological and physiological characteristics, and productive capacity of the cultivars thus affecting the quality of seeds. The aim of this study is to evaluate the effects of doses of molybdenum and plant density on the yield and quality of cowpea seeds, cultivar BRS Novaera. Randomized block design with four replications was used, with the treatments being 4 x 4 factorial, involving four molybdenum rates applied to seeds (0, 40, 80 and 120 g.ha-1) and four population densities (100, 160, 220 and 280 thousand plants.ha-1). After harvesting, productivity was determined, and the seeds were submitted to the following evaluations: moisture content, mass of one thousand seeds, germination, seedling emergence, emergence speed index, length and dry mass of shoot. The application of molybdenum to seeds did not affect production and the quality of the seeds. However, the increase in plant population density led to significant increases in productivity and mass of a thousand seeds.

A glassy carbon electrode modified with a molecularly imprinted polymer (MIP) containing phenacetin recognition sites is introduced. The phenacetin-selective MIP was synthesised based on the electropolymerisation of pyrrole in a 1:1 (v/v) water/ethanol with HClO4 solution. The MIP-modified electrode showed higher recognition ability in comparison with a bare electrode for procaine and aminopyrine, reported to electrochemically interfere in the quantification of phenacetin in cocaine samples. In addition, the MIP was able to preconcentrate one of the intermediates of the phenacetin electrochemical oxidation, acetaminophen, indicating the possibility of monitoring phenacetin based on the acetaminophen oxidation. The acetaminophen oxidation peak is 15 times more detectable compared to the signal obtained by the non-molecularly imprinted polymer (NIP), and it occurs 450 mV below the phenacetin electrochemical oxidation signal. These achieved characteristics decrease the possibility of interference from other electrochemical reactions that may occur in the same potential range as phenacetin electrochemical process.