Chemical data as markers of the geographical origins of sugarcane spirits.

In an attempt to classify sugarcane spirits according to their geographic region of origin, chemical data for 24 analytes were evaluated in 50 cachaças produced using a similar procedure in selected regions of Brazil: São Paulo - SP (15), Minas Gerais - MG (11), Rio de Janeiro - RJ (11), Paraiba -PB (9), and Ceará - CE (4). Multivariate analysis was applied to the analytical results, and the predictive abilities of different classification methods were evaluated. Principal component analysis identified five groups, and chemical similarities were observed between MG and SP samples and between RJ and PB samples. CE samples presented a distinct chemical profile. Among the samples, partial linear square discriminant analysis (PLS-DA) classified 50.2% of the samples correctly, K-nearest neighbor (KNN) 86%, and soft independent modeling of class analogy (SIMCA) 56.2%. Therefore, in this proof of concept demonstration, the proposed approach based on chemical data satisfactorily predicted the cachaças' geographic origins.

Chemical Typification of the Sugarcane Spirits Produced in São Paulo State.

UNLABELLED: To typify São Paulo State sugarcane spirits, 37 chemical compounds were analyzed in 81 Brazilian sugarcane spirits (cachaça), which were produced in different cities from São Paulo State. Among these samples, 56 were distilled in copper alembics, and the other 25 were distilled in steel columns. Hierarchical cluster analysis and principal component analysis were performed with both chemical data sets. The chemical profiles of the cachaças distilled in the column apparatus formed 4 specific clusters, which correspond to 4 distinct geographic regions of São Paulo State. For the cachaças that were distilled in copper alembics, 2 cachaça clusters were formed; however, no correlation between their respective chemical similarities and geographical origins was observed. PRACTICAL APPLICATION: This study aims to differentiate the many sugarcane spirits that are produced throughout Brazil's São Paulo State using chemical analysis with chemometric tools. This contribution is expected to improve the production process of cachaças, map the regions that produce the best cachaças, and assure consumers about a product's provenance.

Correlations between traits in soybean (Glycine max L.) naturally infected with Asian rust (Phakopsora pachyrhizi).

Soybean (Glycine max L.)-breeding programs aim to develop cultivars with high grain yields and high tolerance to Asian soybean rust (Phakopsora pachyrhizi). Considering that the traits targeted for breeding are mainly quantitative in nature, knowledge of associations between traits allows the breeder to formulate indirect selection strategies. In this study, we investigated phenotypic, genotypic, and environmental correlations between the agronomic traits of soybean plants naturally infected with P. pachyrhizi, and identified agronomic traits that would be useful in indirectly selecting soybean genotypes for high yields. The study was conducted on the Capim Branco Farm, Uberlândia, Brazil, with 15 soybean genotypes, which were cultivated in a completely randomized block design with four replications. Fourteen phenotypic traits were evaluated using the GENES software. The phenotypic and genotypic correlations were positive and of a high magnitude between the total number of pods and the number of pods with two or three grains, indicating that the total number of pods is a useful trait for the indirect selection of soybean genotypes for high grain yields. Strong environmental correlations were found between plant height at blooming and maturity and grain yield and yield components.

Development of an integrated flow injection system for the electro-oxidative leaching of uranium from geological samples and its spectrophotometric determination with Arsenazo III.

This work proposes a new procedure for on-line electro-oxidative leaching and spectrophotometric determination of uranium in ore samples. By associating a conventional flow injection system, used for uranium determination with Arsenazo III, with an on-line system for electro-oxidative leaching, a fully integrated system was assembled. The systems were integrated after achieving optimum conditions for uranium determination and leaching. According to the results obtained in the present work, a current density of 280 mA cm(-2) generated enough hypochlorite ions in the electrolyte solution (3.6 mol L(-1) HCl+2% (w/v) NaCl) to promote quantitative oxidation of U(IV) to U(VI) thus improving the extraction efficiency. The slurry density did not significantly affect the performance of the system and the increasing temperature resulted in a decrease in extraction efficiency. This methodology was applied in the determination of U(3)O(8) in four ore samples and the results obtained agreed with those obtained by ICP-MS after conventional wet acid digestion of the samples.