Influencia del procedimiento de extracción en la actividad antioxidante de extractos de semilla de lenteja en un sistema modelo β-caroteno linoleato

Phenolic compounds were extracted from lentil seeds using three solvent systems: 80% (v/v) acetone, 80% (v/v) methanol, and 80% (v/v) ethanol. Each extract was subsequently separated into two fractions by chromatoghraphy on a column with Toyo Pearl HW-40 using water (fraction I) and methanol (fraction II) for elution. Antioxidative activity of extracts and their respective fractions were examined in a β-carotene-linoleate model system. All three extracts exhibited similar antioxidant activity. Considering the level of phenolic compounds in extracts it seems that phenolic compounds from the acetone extract were less active than those from either the methanolic and ethanolic ones. Because the content of phenolics was about 16-fold lower in fraction I of the methanolic and ethanolic extracts compared to fraction II, the phenolics in fraction I of the methanol and ethanol extracts from lentil seeds are much more active than these in fraction II. A stronger antioxidant activity of fraction I from the acetone extract compared to the crude acetone extract was observed during the latter incubation stage. The reason was a relatively high level of phenolic compounds in this fraction. UV spectra confirmed that the phenolic compounds from the acetone extract were different compared to methanolic and ethanolic extracts.Los compuestos fenólicos fueron extraídos de semillas de lenteja usando tres sistemas de disolventes: acetona del 80% (v/v), metanol del 80% (v/v), y etanol del 80% (v/v). Cada extracto fue separado posteriormente en dos fracciones por cromatografía en columna con Toyo Pearl HW-40 usando agua (fracción I) y metanol (fracción II) para la elución. La actividad antioxidante de los extractos y de sus fracciones respectivas fueron examinadas en un sistema modelo β-caroteno-linoleato. Los tres extractos exhibieron actividad antioxidante similar. Atendiendo al nivel de compuestos fenólicos en los extractos parece que los compuestos del extracto acetónico eran menos activos que los metanólicos y etanólicos. Debido a que el contenido de fenoles era aproximadamente 16 veces más bajo en la fracción I de los extractos metanólico y etanólico comparado con la fracción II, los fenoles en la fracción I de los extractos del metanol y del etanol de las semillas de lenteja son mucho más activos que éstos en la fracción II. Una actividad antioxidante más fuerte de la fracción I del extracto acetónico comparado con el extracto acetónico crudo fue observada durante el posterior periodo de incubación. La razón fué el relativamente alto nivel de compuestos fenólicos en esta fracción. El espectro UV confirmó que los compuestos fenólicos del extracto de acetona fueron diferentes comparados con los extractos metanólicos y etanólicos

Green Production of Anionic Surfactant Obtained from Pea Protein

A pea protein isolate was hydrolyzed by a double enzyme treatment method in order to obtain short peptide sequences used as raw materials to produce lipopeptides-based surfactants. Pea protein hydrolysates were prepared using the combination of Alcalase and Flavourzyme. The influence of the process variables was studied to optimize the proteolytic degradation to high degrees of hydrolysis. The average peptide chain lengths were obtained at 3–5 amino acid units after a hydrolysis of 30 min with the mixture of enzymes. Then, N-acylation in water, in presence of acid chloride (C12 and C16), carried out with a conversion rate of amine functions of 90%, allowed to obtain anionic surfactant mixtures (lipopeptides and sodium fatty acids). These two steps were performed in water, in continuous and did not generate any waste. This process was therefore in line with green chemistry principles. The surface activities (CMC, foaming and emulsifying properties) of these mixtures were also studied. These formulations obtained from natural renewable resources and the reactions done under environmental respect, could replace petrochemical based surfactants for some applications

Actividad antioxidante de BHA, BHT y TBHQ examinada con el test de Miller.

In model experiments with the use of Miller's test to 5 ml emulsion 25, 12.5, 6.25 and 3.13µg BHA, BHT and TBHQ was added. Inhibitory ratios (IR) for BHA and BHT were similar. At addition level of 6.25 and 3.13 IR for TBHQ was lower than for BHA and BHT. It is suggested that in the model studies with the use of Miller's test 25 µg BHA, BHT or TBHQ should be added to 5 ml of control sample.En experimentos modelos usando el test de Miller, a 5ml de emulsión se añadió 25, 12.5, 6.25 y 3.13µg de BHA, BHT y TBHQ. Las relaciones inhibitorias (IR) para el BHA y BHT fueron similares. IR para TBHQ fue más baja que para BHA y BHT con niveles de adición del 6.25 y 3.13. Esto sugiere que en estudios modelos usando el test de Miller 25µg de BHA, BHT, o TBHQ deben ser añadidos a 5 ml de muestra control

Efecto de la humedad de la semilla sobre los ácidos fenólicos en torta de semilla de colza

Rapeseeds of 6.5, 8.2, 9.9 and 12.65% moisture were pressed to obtain oil. After two weeks methanol extract of phenolic compounds was obtained from the oil cake. Analysis reveal that there was not effect of seed moisture on the content of total phenolic compounds in extracts and on antioxidative activity of extracts. There were no significant differences in UV spectra or diagrams of derivatives 2 and 4 between the extracts.Semillas de colza de 6'5, 8'2, 9'9 y 12'65% de humedad se prensaron para la obtención del aceite. A las dos semanas se obtuvieron los extractos metanólicos de los compuestos fenólicos a partir de la torta. Los análisis revelaron que no hubo efecto de la humedad de la semilla sobre el contenido de los compuestos fenólicos totales en los extractos y sobre la actividad antioxidativa de los mismos. Tampoco hubo diferencias significativas en los espectros UV o en los diagramas de los derivados 2 y 4 entre los extractos