Analytical and chemometric strategies for elucidation of yerba mate composition.

Yerba mate, a popular plant consumed mainly as an infusion, possesses nutritional and medicinal properties attributed to its secondary metabolites. This study aimed to develop strategies to elucidate the phenolic composition of yerba mate samples from Brazil, Argentina, Uruguay, and Paraguay. Optimization of ultrasonic-assisted extraction (UAE) was performed, and the extracted compounds were characterized using ultra-high-pressure liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF-MS), molecular fluorescence and high-pressure liquid chromatography with diode-array detection (HPLC-DAD). Chemometric analysis, including parallel factor analysis (PARAFAC) and principal component analysis (PCA) explored metabolite profiles and identify patterns. PARAFAC modelling of the molecular fluorescence results revealed higher pigment content in Brazilian samples, while other countries' samples exhibited higher phenolic content. PCA modeling of HPLC-DAD results indicated that cultivated yerba mate contained higher chlorogenic acids levels, and samples from Argentina, Paraguay, and Uruguay exhibited higher concentrations of chlorogenic acids and flavonoids.

Studies related to the chemical composition, biological activities and toxicity of methanolic extracts of noni (Morinda citrifolia) fruits and leaves.

Morinda citrifolia is a plant that grows in Brazilian northeast and presented a wide range of therapeutic, industrial and technological applications. Based on this, the aim of this work was to study the chemical composition, main biological activities and potential toxicity of its extracts, aiming their industrial application. Important compounds were identified in the methanolic extracts obtained by ultrasonic and Soxhlet extractions from leaves and fruits. GC × GC allowed for the identification of phytosterols, fatty acids and methyl esters, besides others (scopoletin, hydrocarbons, alcohols, terpenes). By HPLC-DAD, compounds like catechin, rutin, quercetin could be also identified and quantified. Their content of polyphenols and flavonoids was considered between the international standards. The extracts showed high antioxidant activities (EC50 ∼ 300 µg mL-1, using DPPH assay) compared with those from the literature. The extracts did not show toxicity or mutagenicity, but presented cytotoxicity, which can indicate their use safely in phytotherapic or nutritional applications.

Biodegradation of commercial gasoline (24% ethanol added) in liquid medium by microorganisms isolated from a landfarming site.

Isolation of soil microorganisms from a landfarming site with a 19-year history of petrochemical residues disposal was carried out. After isolation, the bacteria behavior in mineral medium with 1% commercial gasoline (24% ethanol) was evaluated. Parameters employed for microorganism evaluation and selection of those with the greatest degradation potential were: microbial growth; biosurfactant generation and compound reduction in commercial gasoline. Starting from bacteria that presented the best degradation results, consortiums formed by 4 distinct microorganisms were formed. A microbial growth in the presence of commercial gasoline was observed and, for most of the bacteria, degradations of compounds such as benzene, toluene and xylenes (BTX) as well as biosurfactant production was observed. Ethanol was partially degraded by the bacterial isolates although the data does not allow affirming that it was degraded preferentially to the aromatic hydrocarbons investigated. The analyzed consortiums present an efficiency of 95% to 98% for most of the commercial gasoline compounds and a preferential attack to ethanol under the essay condition was not observed within 72 h.