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[structure: see text] The triterpenes 8,14-seco-oleana-8(26),13-dien-3beta-ol (1) and its acetyl derivative 2 were isolated from Stevia viscida and Stevia eupatoria, respectively. Their structures were elucidated by 2D NMR, including carbon-carbon connectivity experiments, and confirmed by X-ray diffraction analysis of ketone 3. The absolute configuration was determined by NMR analysis of the Mosher esters of 1. The biogenetic implications of the new substances are discussed.

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Whey is a by-product of cheese manufacture and contains proteins that can be recovered, but lactose presence limits its use. Proteins can be separated with aqueous two-phase extraction (ATPE), thus the objective was to evaluate this strategy to recuperate proteins from whey attending lactose elimination. An ATPE system with (NH 4 ) 2 SO 4 and polyethylene glycol 4000 (PEG4000) was studied at 25°C. As PEG4000 diminished the volume ratio between phases diminished and a biphasic system was maintained in absence of the polymer. Minimum protein recovering and lactose elimination were 54.5% and 62.1% with mixtures having 25% PEG4000 and 12.1% (NH 4 ) 2 SO 4 , but values were 93.0% and 72.3%, respectively, with 0.1% PEG4000 and 34.7% (NH 4 ) 2 SO 4 . Therefore, whey incorporated with (NH 4 ) 2 SO 4 in concentration higher than 34% and without polyethylene glycol can be used in ATPE systems to maximize lactose elimination and protein recovering and to concentrate proteins up to 2.45 times through a non-energy strategy.Purificación y concentración de proteínas de suero de queso mediante extracción acuosa en dos fases RESUMEN El suero es un subproducto de la manufactura de queso y contiene proteínas que pueden ser recuperadas, pero la presencia de lactosa limita su uso. Las proteínas pueden ser separadas con extracción acuosa en dos fases (ATPE), por lo que el objetivo fue evaluar esta estrategia para recuperar proteínas del suero atendiendo la eliminación de lactosa. Se estudió un sistema ATPE formado con (NH 4 ) 2 SO 4 y polietilenglicol 4000 (PEG4000) a 25°C. A medida que PEG4000 disminuyó se redujo la relación de volúmenes entre fases y en ausencia del polímero se mantuvo un sistema bifásico. El rendimiento mínimo de recuperación de proteínas y eliminación de lactosa fueron 54.5% y 62.1% con mezclas de 25% PEG4000 y 12.1% (NH 4 ) 2 SO 4 , pero los valores fueron 93.0% y 72.3%, respectivamente, con 0.1% PEG4000 y 34.7% (NH 4 ) 2 SO 4 . Por lo tanto, el suero incorporado con (NH 4 ) 2 SO 4 en concentración mayor a 34% y sin polietilenglicol puede ser usado en un sistema ATPE para maximizar la eliminación de lactosa y la recuperación de proteínas y para concentrar proteínas hasta 2.45 veces a través de una estrategia no energética. ARTICLE HISTORY

<p>The phenolic compounds extraction of Prunus serotina Erhr with different ratios of acetone:water, methanol:water and ethanol:wa-ter was optimized using the Taguchi method. The factors evaluated were the solvent mixture and stirring time. The total phenolic content in extracts was assessed by the Folin-Ciocalteu method using gallic acid (GA) as the standard. The maximum value was 20.3 ± 0.86 mg <br />GAE g–1db using acetone:water (7:3, v/v) and 30 min of stirring time.</p>

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