Evaluación bioquímica de fracciones proteínicas de piñón Mexicano (Jatropha curcas L.)

J. curcas seed proteins were fractioned according to the Osborne method and some biochemical properties were determined for these fractions. Glutelins (378 g kg–1 protein) and globulins (201 g kg–1 protein) were the main components. Albumins and prolamins were the minor components. Protein digestibility was highest in glutelins and globulins with values of 81 and 80% respectively. Electrophoresis analysis showed that globulins and glutelins exhibited similar polypeptide profiles. Electrophoresis patterns suggested that there could be a structural relationship among 2S, 7S and 11S storage proteins from plant sources. According to the FAO⁄WHO reference, the protein fractions had acceptable levels of most of the essential amino acids, but its globulins and glutelins were low in lysine and tryptophan.Las proteínas de semillas de J. curcas L. se fraccionaron empleando el método de Osborne y posteriormente se determinaron algunas de sus propiedades bioquímicas y nutricionales. Las fracciones mayoritarias resultaron ser glutelinas (378 g kg–1 de proteína) y globulinas (201 g kg–1 de proteína) mientras que las albúminas y prolaminas fueron las fracciones minoritarias. La digestibilidad de la proteína resultó ser más alta en las glutelinas y globulinas, con valores de 81 y 80% respectivamente. El análisis por electroforesis mostró que las globulinas y glutelinas presentaron perfiles similares, los resultados sugieren que podría existir una relación con proteínas de almacenamiento 2S, 7S y 11S de origen vegetal. Asimismo, de acuerdo con la FAO/WHO, las fracciones proteínicas tuvieron niveles aceptables para la mayoría de los aminoácidos esenciales, sin embargo, las globulinas y glutelinas fueron deficientes en Lys y Trp

Effect of different drying methods on the composition of steviol glycosides in Stevia rebaudiana Bertoni leaves

Drying techniques can modify the composition of certain plant compounds. Therefore, the aim of the study was to assess the effect of different drying methods on steviol glycosides in Stevia rebaudiana Bertoni leaves. Four different drying methods were applied to Stevia rebaudiana Bertoni leaves, which were then subjected to aqueous extraction. Radiation or convection drying was performed in stoves at 60ºC, whereas shade or sun drying methods were applied at 29.7ºC and 70% of relative humi- dity. Stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, dulcoside A, and steviolbioside were quantified by a validated HPLC method. Among steviol glycosides, the content (g 100 g-1 dry basis) of stevioside, rebaudioside A, rebaudioside B, and rebaudioside C varied according to the drying method. The total glycoside content was higher in sun-dried samples, with no significant differences compared to shade or convection drying, whereas radiation drying adversely affected the content of rebaudioside A and rebaudioside C (p <0.01) and was therefore a method lowering total glycoside content. The effect of the different drying methods was also reflected in the proportion of the sweetener profile. Convection drying could be suitable for modern food processing industries while shadow or sun drying may be a low-cost alternative for farmers

Antioxidant and chelating activity of nontoxic Jatropha curcas L. protein hydrolysates produced by in vitro digestion using pepsin and pancreatin

© 2015 Santiago Gallegos Tintoré et al. The antioxidant and metal chelating activities in J. curcas protein hydrolysates have been determined. The hydrolysates were produced by treatment of a nontoxic genotype with the digestive enzymes pepsin and pancreatin and then were characterized by fast protein liquid chromatography and reverse phase chromatography. Peptidic fractions with higher radical scavenging activity were analysed by matrix-assisted laser desorption/ionization mass spectrometry. The antioxidant activity was determined by measuring inhibition of the oxidative degradation of β-carotene and by measuring the reactive oxygen species (ROS) in Caco-2 cell cultures. Cu2+ and Fe2+ chelating activities were also determined. The hydrolysates inhibited the degradation of β-carotene and the formation of ROS in Caco-2 cells. The lower molecular weight peptidic fractions from FPLC had stronger antioxidant activity in cell cultures compared with the hydrolysates, which correlated with a higher content in antioxidant and chelating amino acids. These fractions were characterized by a large presence of peptides with different molecular masses. The hydrolysates exhibited both Cu2+ and Fe2+ chelating activity. It was concluded that J. curcas is a good source of antioxidant and metal chelating peptides, which may have a positive impact on the economic value of this crop, as a potential source of food functional components.This work was supported by the Mexican National Council of Science and Technology (CONACYT), the National Polytechnic Institute (IPN), the Spanish Ministry of Innovation and Science, through Research Project AGL2007-63580, and the European Union through FEDER funds. Thanks are due to María Dolores García-Contreras and Alicia Chagolla for technical assistance.Peer Reviewe

Rheological properties of aqueous dispersions of chia (Salvia hispanica L.) mucilage

The viscoelastic and flow behavior of aqueous dispersions with different concentrations of chia mucilage (Salvia hispanica L.) from Argentina seeds was characterized. The mucilage was obtained by two methods: (I) soaking-freezing-freeze drying-sieving, and (II) soaking-filtration-concentration-freezing-freeze drying. The effect of mucilage concentration, temperature, pH, ionic strength and presence of sucrose on the rheological properties of the aqueous dispersions with the addition of NaCl or CaCl2 was also evaluated. All the dispersion samples presented a shear-thinning behavior and a weak elastic gel-like structure because the storage modulus (G′) was larger than the loss modulus (G″) in the studied frequency range. The concentration of mucilage was the variable with the most significant effect on k (consistency index), whereas the presence of sucrose had the highest effect on n (flow behavior index) and tan δ. The type of salt and extraction method significantly affected k, not affecting n. Tan δ was affected mainly by the type of salt, and some interaction was observed between both factors. Method II and NaCl provided a higher consistency to the dispersions of chia mucilage. These results suggest that chia mucilage could be applied in the production of foods that require additives with thickening capacity, taking advantage of the zero calorific value of this hydrocolloid.Fil: Capitani, Marianela Ivana. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Corzo Rios, L. J.. Universidad Autónoma de Yucatán; México. Instituto Tecnologico Nacional; MéxicoFil: Chel Guerrero, L. A.. Universidad Autónoma de Yucatán; MéxicoFil: Betancur Ancona, D. A.. Universidad Autónoma de Yucatán; MéxicoFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; ArgentinaFil: Tomás, Mabel Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Lima Bean

According to the taxonomy, the bean belongs to the genus Phaseolus, which includes approximately 35 species of which 4 are cultivated: P. vulgaris L.; P. lunatus L.; P. coccineus L., and P. acutifolius L. (Arias-Restrepo et al. 2007). Phaseolus lunatus L. belongs to the Fabaceae family, and there are two domesticated genetic stocks from two different wild forms with two seed morphologies, small and large (Debouk 2019). The small seeds are known as ib., patashete and futuna (Yucatan, Chiapas, and Jalapa, Mexico, respectively), caballero bean (Cuba), ixtapacal (Guatemala), chilipuca (El Salvador), haba (Puerto Rico and Panama), sieva and comba (Colombia), and guaracaro (Venezuela), among others. The large seeds are known as lima, layo and pallar (Peru), torta (Colombia), palato (Bolivia), and manteotto (Argentina) (Debouk 2019). It is proposed that P. lunatus could have originated in the Neotropical region of America, ranging from Mexico to Chile, passing through the Andean region of Peru. It is believed that its origin is found in Guatemala since in this area the wild progenitor of this species was found; on the other hand, molecular studies propose that its origin is found in the Andean zone and that its distribution throughout the Americas was given by domestication (FAO 2018)