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The aim of this study was to evaluate the effects of chitosan-tomato plant extract (C-TPE) edible coating (EC) applications on the physicochemical, microbiological, sensory and antioxidant capacity of chicken during storage. Edible coatings prepared with chitosan 1%, acetic acid 1%, glycerol and TPE (0.1 and 0.3%) were tested. The slices were submerged for 1 minute in different treatments (T1: C 1%; T2: C 1% + TPE 0.1%; T3: C 1% + TPE 0.3%; T4: control) and stored at 4 °C. At the end of the storage period, the treatments exhibited the greatest physicochemical and microbiological effects in the slices, reducing the microbial population relative to the control. The T2 treatment exhibited the highest antioxidant capacity, total phenolic content and overall acceptance. The results demonstrate that the application of C with the addition of a natural extract, such as those from the tomato plant, can be an alternative method for preserving chicken meat.

Starch is composed of amylose and amylopectin and deposited as granules of different sizes and shapes with semi-crystalline and amorphous concentric layers that show the ‘maltese cross’. Starches from different sources show variable chemical composition as well as the structure of their components that are involved in thermal properties. Amylose, lipids, phosphorylated residues and long lateral chain amylopectin interact among them avoiding water uptake. In contrast, high amylopectin contents, especially with short lateral chains, allow hydration via hydrogen bonds to form gels with the tendency to retrogradation. Smaller starch granules have a larger superficial area, surface pores, and channels that enhance water uptake. High hydration increases the swelling, viscosity, and gelatinization ability of starch granules. The knowledge of those properties allows the selection of the most appropriate starch for a specific end use. This review discusses the relationship between the physicochemical composition of the starch and their rheological properties.

Subsurface flow constructed wetlands (SSFCW) are currently under evaluation as a promising treatment option for removal of As from drinking water. Issues to consider are selection of plant species capable of accumulating As in addition to choosing a substrate for the bed material which demonstrates a strong sorptive capacity for As. In this study, our goal was to evaluate the removal of total As in a subsurface flow constructed wetland mesocosm containing an iron oxide substrate (tezontle) both without plants and containing two plant species, Zantedeschia aethiopica and Anemopsis californica for phytoremediation of As-contaminated groundwater. Local As contaminated groundwater, which averaged 34 ± 11 μg/L, was used in this 6 month experiment. Inflow and outflow concentrations of total As, chloride, sulfate, fluoride, pH and TDS, were determined over time. Evapotranspiration (ET) was also measured during the experiment in order to correct for water loss by ET, which tends to concentrate the solute of interest. The total As mass removal efficiencies during the first three months were 57.7 ± 7.1, 75.2 ± 7.1 and 77.8 ± 7.1% in the control (not planted), Z. aetiopica -planted and A. californica -planted cells, respectively. The planted cells had a statistically greater As removal efficiency ( p -value = 0.0012) than the substrate only cells. During the 6 months, the concentration of As in the effluent was significantly lower in the planted vs the unplanted cells ( p -value = 0.045) at 23, 18 and 18 μg/L, in the control (not planted), Z. aetiopica -planted and A. californica -planted cells, respectively. These results suggest that the presence of plants ( Z. aethiopica and A. californica ) increased As removal in a batch-fed subsurface flow constructed wetland system.

Anemopsis californica, commonly known as yerba mansa, is an important medicinal plant that has traditionally been used to treat a variety of digestive, respiratory and skin ailments, and has been reported to possess anticancer properties. The increase in demand for this medicinal plant puts wild populations at risk due to over-harvesting; therefore, the development of alternatives such as in vitro propagation may help reduce this pressure on natural plant resources. The aim of this work was to develop protocols for the in vitropropagation of A. californica through axillary bud proliferation and somatic embryogenesis. Shoot bud multiplication was achieved using nodal explants from axenic seedlings, reaching the highest multiplication rate (on average 15 shoots per explant) when the culture medium was supplemented with 4 mg/L kinetin. Propagated shoots produced roots in medium containing 1 mg/L indole-3-butyric acid. Best induction of somatic embryogenesis (on average 19.75 embryos per explant) was obtained from leaf explants cultured on medium supplemented with 4 mg/L naphthalene acetic acid. These protocols may be used either for the commercial mass propagation of the species, studies on the production of secondary metabolites or as a basis for the development of genetic improvement strategies. Key words: Multiple shoot proliferation, regeneration of embryos, plant growth regulators,yerba mansa.

The aim of this study was to characterize the phenolic constituents and evaluate the antioxidant activity of five pepper (Capsicum annuum L.) cultivars harvested in the same season, geographic area and climatic conditions. Phenols, flavonoids and ascorbic acid of Anaheim, Bell, Caribe, Jalapeno and Serrano peppers were quantified, and antioxidant activity of their extracts were evaluated by the method of radical scavenging of DPPH and ABTS+. It was found that Serrano pepper had the highest ascorbic acid content, followed by Bell and Caribe, whereas the lowest values were found in Jalapeno and Anaheim. The highest contents of phenolic compounds were in Caribe and Bell peppers. The total flavonoid contents ranged from 25.38 ±3.44 (Anaheim) to 60.36 ±9.94 mg QE/100g fw (Caribe). The Bell and Caribe extracts showed the highest (p0.05) stabilization of ABTS+. The highest oxidation inhibition percentage for radical DPPH was observed in Caribe extract, coinciding with the highest levels of gallic acid, chlorogenic acid, epicatechin, rutin, luteolin, resveratrol (r 0.85) and ascorbic acid. In conclusion, among the pepper cultivars studied, Caribe and Bell showed to have the best antioxidant properties and can be suggested as preferable for human consumption