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Biodegradable films of chia by-products (mucilage and protein-rich fraction (PF)) incorporated with clove essential oil (CEO) were obtained and characterized. The effects of polymer concentration (PC; 1.0-3.0 %, w/ v) and CEO concentration (0.1-1.0 %, v/ v) were evaluated as well as the pH (7-10), using a 2 factorial design with four central points. The films exhibited moisture values between 11.6 and 52.1 % (d.b.), which decreased ( p < 0.05) with increasing PC and CEO. The thickness of the films increased ( p < 0.05) with increasing PC. PC and pH influenced ( p < 0.05) the lightness ( L) and variation in color between red and green ( a). The orientation of the color to yellow-blue hues ( b) decreased significantly ( p < 0.05) with increasing PC. Transparency was significantly lower and higher ( p < 0.05) than PC and CEO, respectively. The film surface morphology was evaluated using atomic force miscrocope images, and thermogravimetric analysis (TGA) was performed to study the thermal stability of the films. The displacement and tensile strength were significantly lower ( p < 0.05) at higher concentrations of CEO, this variable being the only one with a significant effect. The chemical composition of the films was confirmed utilizing Fourier transform infrared (FTIR) spectroscopy. The proportion of CEO added to the films had a significant influence on antimicrobial activity, inhibiting the growth of both Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

In this study a new wheat bread was designed whose sugars were replaced with S. rebaudiana Bertoni aqueous extract. The impact of the S. rebaudiana Bertoni aqueous extract on nutritional and sensory quality, its ability to reduce sugar intake and its antioxidant properties were investigated. Functional bread with 50 % of sugars replaced with S. rebaudiana extract was compared with traditional wheat bread. The extract demonstrated alpha amylase (IC = 198.40 μg/mL) glucosidase (596.77 μg/mL) inhibition. The radical scavenging activity exhibited an IC value of 335.94 mg/mL. In comparison with the control, the bread with stevia extract was softer and had lower microbial growth during the shelf-life study. The sensory test showed that the substitution of 50 % stevia extract was more acceptable when comparing with all quality characteristics. Regarding the nutritional contribution, the content of dietary fiber and digestible carbohydrates in the bread with stevia extract was higher and lower respectively, so caloric intake was significantly reduced. The results showed that the biological properties of S. rebaudiana extract were retained after the bread making process and that the proposed bread is suitable as functional food in human nutrition. [ABSTRACT FROM AUTHOR]

A full understanding of the ecology and evolution of plant tolerance to damage requires the measurement of a diversity of traits (including multiple fitness-correlates) and underlying mechanisms. Here, we address the compensatory response to defoliation in the perennial herb Ruellia nudiflora, measure biomass allocation patterns and relate them to compensation, and address multiple mechanisms and traits that determine compensatory ability. We used maternal full-sib lines of R. nudiflora and conducted a defoliation experiment in which half the plants of each line were subjected to removal of 40% of leaf area (the other half remained undamaged). Fitness-correlated traits, physiological traits, and leaf longevity were measured during a 2-month period after defoliation. Using another set of plants, we conducted a second defoliation experiment and measured the concentration of non-structural carbohydrates to test for root-to-shoot carbon mobilization as a compensatory mechanism. R. nudiflora showed full compensation in terms of fruit output, and compensatory ability was positively correlated with investment in root biomass in the absence of damage. In addition, defoliated plants produced shorter-lived leaves and had a greater concentration of starch in roots, suggesting that reduced leaf longevity and accumulation of below-ground carbon reserves act as compensatory mechanisms. By measuring multiple fitness-correlates and induced traits, we provide a comprehensive evaluation of R. nudiflora compensatory responses to herbivory. [ABSTRACT FROM AUTHOR]