Quantificação de contaminantes em aguardentes de cana/cachaças de alambique e de coluna

In the present study aimed to characterize and quantify four contaminants (ethyl carbamate, 2,3-butanedione, furfural and 5-hydroxymethylfurfural) present in alembic cachaça and industrial. Were collected forty-four samples of cachaça in the southern regions, the Midwest, southeast of Minas Gerais and São Paulo state, and subsequently subjected to physical, chemical and chromatographic analyzes. The physicochemical analyzes were performed according to the methodology described by the Ministry of Agriculture, Livestock and Supply (MAPA). The ethyl carbamate, 2,3-butanedione, furfuaral and 5 hydroxymethylfurfural were characterized and quantified by high-performance liquid chromatography (HPLC). The results of the ethyl carbamate analysis, it was found that both samples showed column cachaças outside the standards required by law, with the values 245.31 235.53 L-1 ug and none of the liquor samples alembic showed concentration greater than 210.0 ug L-1 , and the method is very sensitive to low limits of detection and quantification. In determining 2,3-butanedione, it was revealed that the column cachaças showed higher levels of contaminants when compared to cachaça alembic. In the quantification of furfural and 5-hydroxymethylfurfural was developed and validated analytical methods employed to high-performance liquid chromatography (HPLC) with DAD detector. Samples column cachaças showed higher values than the limit established by Brazilian legislation and ranged from 7.00 to 5.63 mg / 100 ml of anhydrous alcohol over the alembic cachaça.

Análise da expressão dos genes da subfamília DREB em resposta à seca em plantas de Coffea canephora Conilon

Coffea canephora is one of the most economically important coffee species and in Brazil, Conilon is the most widely cultivated plant of this species. Abiotic stresses such as temperature variations and drought periods are factors that significantly affect their production and tend to worsen with globally recognized climate changes. In an attempt to understand the molecular responses of coffee plants in water deficit conditions, recent studies have identified candidate genes (CGs) as CcDREB1D. This gene showed increased expression in response to drought in the leaves of clone 14 (drought tolerant) in relation to the clone 22 (sensitive to drought) of C. canephora Conilon. Based on these results, the identification of DREB genes and their subgroups (SGs) of C. canephora, the objective is to analyze in silico and also in vivo these genes expression in leaf and root of tolerant (14, 73 and 120) and sensitive clones (22) of C. canephora Conilon submitted or not to a water deficit. In silico expressions of all DREB genes were analyzed from the Coffee Genome Hub Database and in vivo expression was performed by the technique "reverse transcription-quantitative PCR" (RT-qPCR). In silico gene expression analysis was possible to identify DREB genes with potential responses to abiotic stresses, corroborating some validated in vivo results. In this analysis, several genes showed differential expression in response to drought among the SGs (IIV), the tolerant and sensitive clones and the leaf and root. These differentially expressed genes were identified as potential CGs and among them, it was found that most tolerant clones showed increased expression in relation to sensitive in response to drought, with higher expression levels for clones 14 and 73. These highest levels were observed in leaves compared to the roots and SG-I stood at greater number of genes expressed in response to drought. These results suggest that DREB CGs, as Cc05_g06840, Cc02_g03420 e Cc08_g13960, play an important role in the regulatory mechanisms of response to drought in C. canephora Conilon.

New voltammetry-based technique for the determination of tebuthiuron in crystal and brown sugar samples

Sugar is widely consumed worldwide and Brazil is the largest producer, consumer, and exporter of this product. To guarantee proper development and productivity of sugar cane crops, it is necessary to apply large quantities of agrochemicals, especially herbicides and pesticides. The herbicide tebuthiuron (TBH) prevents pre- and post-emergence of infesting weed in sugarcane cultures. Considering that it is important to ensure food safety for the population, this paper proposes a reliable method to analyse TBH in sugar matrixes (brown and crystal) using square wave voltammetry (SWV) and differential pulse voltammetry (DPV) at bare glassy carbon electrode and investigate the electrochemical behavior of this herbicide by cyclic voltammetry (CV). Our results suggest that TBH or the product of its reaction with a supporting electrolyte is oxidized through irreversible transfer of one electron between the analyte and the working electrode, at a potential close to +1.16 V vs. Ag |AgClsat in 0.10 mol L-1 KOH as supporting electrolyte solution. Both DPV and SWV are satisfactory for the quantitative analysis of the analyte. DPV is more sensitive and selective, with detection limits of 0.902, 0.815 and 0.578 mg kg-1, and quantification limits of 0.009, 0.010 and 0.008 mg kg-1 in the absence of the matrix and in the presence of crystal and brown sugar matrix, respectively. Repeatability lay between 0.53 and 13.8%, precision ranged between 4.14 and 15.0%, and recovery remained between 84.2 and 113% in the case of DPV conducted in the absence of matrix and in the presence of the crystal sugar matrix, respectively.

Atividade microbiana e diversidade de fungos micorrízicos arbusculares em espécies arbóreas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Matéria seca, teores de macronutrientes e produtividade de soja transgênica e não transgênica com diferentes manejos de plantas daninhas

Pós-graduação em Agronomia - FEIS

Quantificação do carbono da biomassa microbiana, do carbono do 'CO IND. 2' liberado e micorrização em função da calagem e do manejo do solo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dinâmica espaço-temporal e quantificação dos danos e perdas da murcha de Ceratocystis em eucalipto na produção de carvão vegetal

Pós-graduação em Ciência Florestal - FCA

Resistência da seringueira ao mal das folhas e modelagem no patossistema Hevea sp. – Microcyclus ulei através dos parâmetros monocíclicos

Pós-graduação em Ciência Florestal - FCA

Avaliação de cultivares de milho em função de populações de plantas e épocas de semeadura

Pós-graduação em Agronomia (Agricultura) - FCA

Estudo etnobotânico nas comunidades de Porto Limão, Porto Alambrado e Campo Alegre, na fronteira Brasil-Bolívia, Mato Grosso Brasil

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Análise da composição e estrutura da comunidade arbustivo-arbórea de savana no sudoeste de Mato Grosso-Brasil

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Ação protetora do óxido nítrico em plantas de soja (Glycine max L. Merril) submetidas ao lactofen

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Distribuição espacial de Pratylenchus brachyurus em soja no leste do Maranhão

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Compostos bioativos em frutas cítricas: quantificação, avaliação da atividade antioxidante, parâmetros de cor e efeito da pasteurização

Pós-graduação em Alimentos e Nutrição - FCFAR

Estimativas do IWV utilizando receptores GPS em bases terrestres no Brasil: sinergia entre a geodésia e a meteorologia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)