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).

Production of volatile compounds by yeasts using hydrolysed grape seed oil obtained by immobilized lipases in continuous packed-bed reactors.

Lipases CAL-B, TLL, and RML were used in the synthesis of free fatty acids of grape seed oil as heterogeneous substrate. The best enzyme was used to optimize the reaction variables temperature, enzyme content, and molar ratio of water:oil in batch reactions using experimental planning. The ideal conditions to produce free fatty acids using pure RML were 45 °C, 12:1 substrate molar ratio, and 15% enzyme, resulting in 66% of oil hydrolysis and a productivity of 0.

Wine lees from the 1st and 2nd rackings: valuable by-products.

Phenolic compounds of the first and second racking wine lees, including anthocyanins, were qualitatively and quantitatively analyzed by HPLC-DAD-MS. Wine lees from both rackings displayed similar chromatographic profiles. Therefore, it was impossible to differentiate the qualitative results regarding phenolic compounds.

Chemical characterisation of Piper amalago (Piperaceae) essential oil by comprehensive two-dimensional gas chromatography coupled with rapid-scanning quadrupole mass spectrometry (GC×GC/qMS) and their antilithiasic activity and acute toxicity.

Introduction: Piper amalago has a distribution from Mexico to Brazil; their aerial parts have been used in folk medicine to treat diuretic and kidney diseases.

Objective: The purpose of this study was to obtain a deeper understanding of the chemical composition of essential oils (EOs) extracted from both the leaves and stems of P. amalago, compare them, and evaluate their antilithiasic activity and acute toxicity.

GC×GC/qMS analyses of Campomanesia guazumifolia (Cambess.) O. Berg essential oils and their antioxidant and antimicrobial activity.

The present study investigated the essential oil obtained from Campomanesia guazumifolia (Cambess.) O. Berg, an aromatic plant used in Brazilian folk medicine.

Quantification of nitrogen compounds in diesel fuel samples by comprehensive two-dimensional gas chromatography coupled with quadrupole mass spectrometry.

Although several methods for the analysis of nitrogen compounds in diesel fuel have been described in the literature, the demand for rapid, sensitive, and robust analyses has increased in recent years. In this study, a comprehensive two-dimensional gas chromatographic method was developed for the identification and quantification of nitrogen compounds in diesel fuel samples. The quantification was performed using the standard addition method and the analysis was conducted using comprehensive two-dimensional gas chromatography coupled with fast quadrupole mass spectrometry.

Comprehensive two dimensional gas chromatography with fast-quadrupole mass spectrometry detector analysis of polar compounds extracted from the bio-oil from the pyrolysis of sawdust.

In this paper it is studied the most polar fractions of bio-oil produced by fast pyrolysis of Lignocel BK40-90 (sawdust from forest timber). The biomass was submitted to the pyrolysis in an existing FCC pilot plant that was adapted for this procedure. The equipment consists of a fluidized bed reactor with nitrogen injection.

Characterization of the yerba mate (Ilex paraguariensis) volatile fraction using solid-phase microextraction-comprehensive 2-D GC-MS.

The present research is focused on the use of a solid-phase microextraction-comprehensive 2-D GC methodology, in the analysis of the volatile fraction of yerba mate. Yerba mate is used for the generation of a tea-like beverage, widely consumed in South America. A rapid-scanning quadrupole mass spectrometer (qMS), employed as a detection system and operated at a 25 Hz scanning frequency, supplied high-quality mass spectra.

High efficiency liquid chromatography techniques coupled to mass spectrometry for the characterization of mate extracts.

There is growing interest related to rapid screening and full characterization of the constituents of plants with medicinal properties; among these, "Mate" or Yerba Maté is a tea-like beverage widely consumed in South America, obtained from the dried leaves of Ilex paraguariensis. The high content in polyphenols accounts for in vitro and in vivo antioxidant activity of the extracts obtained from this plant; on the other hand, the high complexity of the samples extracted, depending on the method employed, may preclude complete resolution by conventional HPLC techniques. For this purpose, a comprehensive two-dimensional liquid chromatography (LC x LC) system, comprised of an RP-Amide first dimension and a partially porous octadecylsilica column in the second dimension, has been compared with a one-dimensional system.

Pressurized liquid extraction of mate tea leaves.

The objective of this work is to investigate the influence of process parameters on the pressurized liquid extraction (PLE) of Ilex paraguariensis leaves. A factorial 2(6-2) experimental design was employed using responses as the extraction yield and the chromatographic profile of the extracts. The extraction time, polarity of solvent, amount of sample, numbers of PLE cycles, flushing volume and extraction temperature were selected as independent variables (factors).

Extraction of grape seed oil using compressed carbon dioxide and propane: extraction yields and characterization of free glycerol compounds.

The main objective of this work was to compare the extraction of grape seed oil with compressed carbon dioxide and propane on the extraction yields and chemical characteristics of free glycerol compounds. The experiments were performed in a laboratory scale unit in the temperature range of 30 to 60 degrees C and pressures from 60 to 254 bar. The results showed that propane is a more suitable solvent for grape seed oil extraction than carbon dioxide, as higher extractions yields and a very fast kinetic of extraction were achieved with this solvent.

Pressurized liquid extraction of vitamin E from Brazilian grape seed oil.

The goal of this paper is to optimize the pressurized liquid extraction (PLE) of vitamin E from grape seed oil from residues of the wine industry. For this purpose an experimental planning to optimize the extraction of Brazilian grape seed oil by means of PLE with hexane as solvent was applied and the results are compared with conventional methods (Soxhlet and mechanical press extraction). Vitamin E was separated and analyzed using HPLC with UV detection.

Influence of drying methods and agronomic variables on the chemical composition of mate tea leaves (Ilex paraguariensis A. St.-Hil) obtained from high-pressure CO2 extraction.

The main objective of this work is to assess the influence of two drying methods (microwave and vacuum oven) and some agronomic variables (plant fertilization conditions and sunlight intensity) on the characteristics of mate tea (Ilex paraguariensis) leaves extracts obtained from high-pressure carbon dioxide extractions performed in the temperature range from 20 to 40 degrees C and from 100 to 250 bar. Samples of mate were collected in an experiment conducted under agronomic control at Ervateira Barão LTDA, Brazil. Chemical distribution of the extracts was evaluated by gas chromatography coupled with a mass spectrometer detector (GC/MS).

Influence of agronomic variables on the macronutrient and micronutrient contents and thermal behavior of mate tea leaves (Ilex paraguariensis).

The influence of agronomic variables (light intensity, age of leaves, and fertilization type) on the content of macronutrients and micronutrients (potassium, calcium, sodium, magnesium, manganese, iron, zinc, and copper) of tea leaves was assessed by acid digestion, followed by flame atomic absorption spectrometry (FAAS). The thermal behavior of mate tea leaves (Ilex paraguariensis) was also studied in this work. Samples of mate (Ilex paraguariensis) were collected in an experiment conducted under agronomic control at Erva-Mate Barão Commerce and Industry LTD (Brazil).

Optimization of pressurized liquid extraction of Piper gaudichaudianum Kunth leaves.

Piperaceae family is original from tropical regions and it shows more than 700 species around the world. Piper gaudichaudianum Kunth is the specie more abundant in Brazil, occurring from Northeast to South Brazil. In this paper, it was investigated the influence of some experimental parameters on the pressurized liquid extraction (PLE) of P.

The use of ultrasound in the extraction of Ilex paraguariensis leaves: a comparison with maceration.

The objective of this work is to discuss the main parameters that influence the sonication extraction of Ilex paraguariensis leaves. For this purpose, the extraction time, solvent polarity, solvent volume, sample mass and particle size were evaluated. Results showed that the main variable affecting the extraction process was the solvent polarity.

Influence of agronomic variables on the composition of mate tea leaves (Ilex paraguariensis) extracts obtained from CO2 extraction at 30 degrees C and 175 bar.

The aim of this work is to assess the influence of light intensity (plants with direct sun exposure and in a controlled light intensity) and age of leaves (6-24 months) on the characteristics of the extracts of mate tea leaves obtained from carbon dioxide at high pressures. Samples of mate were collected in an experiment conducted under agronomic control at Industria e Comercio de Erva-Mate Barão LTDA, Brazil. The content of selected organic compounds of the extracts was evaluated by gas chromatography together with mass spectrometry.