Utilisation of soybean post-production waste in single- and double-layered films based on furcellaran to obtain packaging materials for food products prone to oxidation.

Single-layered films, based on furcellaran and protein hydrolysates from soybean bran (1st layer), were obtained. Moreover, a procedure for the preparation of double-layered films was developed, in which an ethanol extract from soybean bran was deposited onto the 1st layer. It was checked how the addition of the 2nd layer affects the functional properties of the film. The addition of the 2nd layer increased the thermal properties, modulus of elasticity and antioxidant activity, while decreases were noted for tensile strength and elongation at break parameters. The films were used as packaging materials for storing butter and the active films did not extend the quality of butter during storage, however, they behaved in the same way as synthetic films. Therefore they have the potential to be used as packaging material instead of a synthetic film.

A New Approach for the Production of Selenium-Enriched and Probiotic Yeast Biomass from Agro-Industrial by-Products in a Stirred-Tank Bioreactor.

The production of biomolecules using agro-industrial by-products as feedstock is a growing trend worldwide. Selenium (Se) is a trace element essential for health, and the Se-enrichment of yeast biomass can enhance its benefits. This study investigated the feasibility of the production of Saccharomyces cerevisiae Se-enriched biomass using a medium composed of corn bran and soybean bran acid hydrolysates as carbon and nitrogen sources in a stirred-tank reactor. After hydrolysis, hydrolysates presented complex composition and high concentrations of sugars, proteins, and minerals. The use of a stirred-tank bioreactor leads to the production of 9 g/L S. cerevisiae biomass enriched with 236.93 µg/g Se, and 99% cell viability. Likewise, the combination of sugarcane molasses and soybean bran hydrolysate was effective for cell growth of a probiotic strain of S. cerevisiae with a 24.08% ß-glucan content. The results demonstrated that starchy acid hydrolysates are low-cost and efficient substrates for the production of yeast biomass and derivate products and may contribute to further studies for a sustainable development of biorefinery technologies.

Zearalenone reduction by commercial peroxidase enzyme and peroxidases from soybean bran and rice bran.

The peroxidase (POD) enzyme, obtained from different sources, has been described in the literature regarding its good results of reduction in concentration or degradation levels of mycotoxins, such as aflatoxin B1, deoxynivalenol and zearalenone (ZEA). This study aimed at evaluating the action of commercial POD and POD from soybean bran (SB) and rice bran (RB) in ZEA reduction in a model solution and the characterisation of the mechanism of enzyme action. POD was extracted from SB and RB in phosphate buffer by orbital agitation. Evaluation of the action of commercial POD and POD from SB and RB in ZEA reduction was carried out in phosphate buffer and aqueous solution, respectively. Parameters of (Michaelis-Menten constant) (KM) and maximal rate (Vmax) were determined in the concentration range from 0.16 to 6 µg mL-1. ZEA reduction was determined and the mechanism of enzyme action was characterised by FTIR and high-pressure liquid chromatography-electrospray tandem mass spectrometry. Commercial POD and POD from RB and SB reduced ZEA concentration by 69.9%, 47.4% and 30.6% in 24 h, respectively. KM values were 39.61 and 8.90 µM, whereas Vmax values were 0.170 and 0.011 µM min-1 for commercial POD and POD from RB, respectively. The characterisation of the mechanism of enzyme action showed the oxidoreductive action of commercial POD in the mycotoxin. The use of commercial POD and POD from agro-industrial by-products, such as SB and RB, could be a promising alternative for ZEA biodegradation.

La cascarilla de la soja: potencial componente de alimentos funcionales / Soybean hull: potential ingredients for functional foods

The effects of soybean bran, a residue of soybean oil extraction, rich in dietary fiber-both soluble and insoluble -on fat distribution, plasmatic and liver lipids, glycemia and glycemic load, were studied on adult male obese diabetic 0 rats. Two hundred days old ft rats were fed two diets with 15 percent sodium caseinate as protein source and 10 percent dietary fiber from soybean bran (S) or cellulose (C) during 30 and 60 days. Significant diminutions in blood cholesterol levels were registered in group S on day 30 as well as on day 60. Diet S significantly attenuated the characteristic increase in blood triacylglycerols levels and the usual progressive increase in blood glucose levels expressed in this line of rats. Diet S decreased significantly liver total lipids, cholesterol and triacylglycerols compared with C. No differences were registered between groups neither in food intake nor in biomass. These effects are attributed to the combined effects of the soluble and insoluble fiber fractions present in soybean bran. In conclusion, soybean bran may be considered as a useful component of functional foods designed for human nutrition.

Se estudiaron los efectos de la cascarilla o salvado de la soja, con alto contenido de fibra dietaria, de tipo insoluble y soluble, sobre la distribución del tejido adiposo, el perfil lipídico sanguíneo y hepático, la glicemia basal y post sobrecarga glucídica, en ratas adultas de la línea IIMb/p, obesa y diabética. Ejemplares de 200 días fueron alimentados durante 30 y 60 días con dos dietas con caseinato como fuente proteica y 10 g/100g de fibra de salvado de soja (S) o celulosa microcristalina (C). Tanto a los 30 como a los 60 días de tratamiento se constataron niveles de colesterol sérico significativamente menores en el grupo S con respecto a C. Los valores de C fueron asimismo superiores a los del inicio del experimento. La dieta S atenuó el aumento de los triacilgliceroles séricos, manifestado en el grupo C y el progresivo aumento de la glucemia basal habitual en estos roedores. Se registró una significativa disminución de los lípidos totales, el colesterol y los triacilgliceroles hepáticos en el grupo S. Se atribuyen estos efectos, a los mecanismos fisiológicos combinados de las fracciones de fibra del salvado de la soja. Se concluye que este producto podría evaluarse en humanos como un potencial componente de alimentos funcionales.