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A sulfated polysaccharide from Navicula incerta (SPNi) was extracted, and its physicochemical characteristics, antioxidant activity, and anti-hemolytic property were investigated. The polysaccharide yield was 4.8% (SPNi weight/biomass dry weight). Glucose, galactose, mannose, and xylose were the primary sugars. The sulfate content and Mw values were 0.46% and 45 kDa, respectively. The FT-IR spectrum showed characteristic bands at 3276,1079,1255, and 820 cm−1, related to -OH, C-O-C, S=O, and C-O-S stretching vibration. The 1H-NMR analysis revealed signals of anomeric protons, indicating the presence of CH2-O and CH-O groups. SPNi registered ferric-reducing antioxidant power (up to 1.47 µmol TE/g) and 54% anti-radical activity on ABTS+. This polysaccharide registered 90% hemolysis inhibition achieving integrity of the erythrocyte membrane. The results indicate that SPNi could be a candidate for biotechnology applications where antioxidant activity and hemolysis inhibition are required.

Considering the FAO perspectives for agriculture towards 2030 many natural sources will be no longer profitable for the synthesis of many biomaterials; however, triticale (X Triticosecale Wittmack) is a cereal crop synthetized to withstand marginal agricultural conditions, used primarily as fodder throughout the world. The synthesis of a novel anionic hydrogel with pH stimulus-response was developed based on Eronga triticale starch as sustainable biomass, using citrate (pKa~3.1, 4.7 and 6.4) as crosslinking agent. By scanning electron microscopy and X-ray diffraction, starch granules exhibited size and semi-crystallinity A-type. The presence of the anionic sensing group (COOH) was verified by infrared spectroscopy, and by a thermal analysis the hydrogels exhibited four endothermic curves (115-393°C, ~1.4-38 kJ/mol activation energy). The rheological analysis showed viscoelastic tendency (G’>G’’) and good stability (Tan δ

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.

Chitosan films (CF) [1 and 2% w/v] alone and with cinnamaldehyde (CNE) [0.25, 0.5 and 1% v/v] were prepared using an emulsion method, and the obtained films were characterized in terms of water vapor permeability (WVP), water solubility and optical, mechanical and antioxidant properties. The incorporation of CNE at 1% (v/v) significantly decreased the water solubility of the film by approximately 4% for the 1 and 2% CF films, whereas the WVP increased (2.5–3.5 times). The incorporation of CNE (0.25 and 0.5%) into 2% CF significantly increased the tensile strength (TS) (62 and 34%, respectively) and the percent elongation (%E) values, 26, 30 and 52% for CF that contained 0.25, 0.5 and 1% CNE, respectively. The largest value of the elasticity modulus (EM) was observed for 2% CF with 0.25% CNE. All films exhibited a yellow appearance (b*), but the CNE content had a marked impact on the coloration of the films. The CNE recoveries of the CF films (1 and 2%) with 1% of CNE were high (43 and 67%). The antioxidant activities indicated that the incorporation of 1% CNE into CF films (1 and 2%) increased the antioxidant activity. The protective effects of the films with and without CNE on erythrocytes were very strong (36–72% hemolysis inhibition). These results suggest there are potential applications for CF-CNE films as active packaging for the preservation of food products.

Stenocereus thurberi is an endemic species in northwestern Mexico. It produces colorful fruits called pitayas that have an edible pulp. They have phytochemical compounds associated with biological activities. Ultrafiltration is a widely used method for the clarification of fruit juices and the recovery of phytochemicals. However, its effect has not been extensively studied in extracts. Therefore, the objective of this work is to study the effect of the ultrafiltration of pitaya extract (Stenocereus thurberi) on its phytochemical content, antioxidant capacity, and identification of phenolic compounds by UPLC-DAD-MS, providing greater knowledge about the pitaya. In this study, two extracts were analyzed, the unclarified extract (UE) and the clarified extract (CE). The antioxidant capacity was higher in the CE with 15.93 ± 0.42 mM TE/g, DPPH and 18.37 ± 0.016 mM TE/g, ABTS. The UPLC-MS analysis indicated the decrease in phenolic compounds in the CE and the presence of gallic acid and resorcinol, compounds that had not been identified in other species of Stenocereus spp. The correlation analysis indicated that all the phytochemicals present in the pitaya contribute significantly to the antioxidant capacity. The ultrafiltration process could be a viable option to improve the biological activity of the natural extracts.

The present study was accomplished to gain insights into the biochemical and kinetic properties of Rhyzopertha dominica’s α-amylase isoforms (named RdA70, RdA79, and RdA90) expressed in progenies reared in wheat varieties differing in α-amylase inhibitory activity. An inverse relationship was observed between the progenies’ amylase activity and the wheat inhibitory activity. Wheat samples with a high and low infestation (named HI-Borlaug and LI-Villa Juarez, respectively) were chosen to simplify the study. The progenies amylases were isolated by hydrophobic interaction chromatography, while the wheat samples were analyzed in α-amylase inhibitory activity by size exclusion chromatography. The isoforms RdA70 and RdA90 from LI-Villa Juarez progeny showed higher enzyme activities (73.8 and 43.4%, respectively) than those from HI-Borlaug. When the amylase isoforms were tested in susceptibility to inhibition by the inhibitory albumins, those from LI-Villa Juarez were more susceptible than those of the HI-Borlaug. Determination of the kinetic parameters revealed that RdA70 from the HI-Borlaug progeny showed 3.0-fold less starch affinity than that from the LI-Villa Juarez (Km of 12.3 ± 1.8 versus 4.0 ± 0.3). The rest of the α-amylases did not show the same pattern as RdA70 in the HI-Bourlag as that their starch affinity was further reduced (RdA79 Km = 23.1 ± 4.3, RdA90 Km = 17.1 ± 2.9). Estimation of IC50 values confirmed the high sensitivity of the three α-amylases of the LI-Villa Juarez progeny to wheat α-amylase inhibitors. The inhibitor constant Ki was the lowest for RdA70 in the LI-Villa Juarez progeny indicating the inhibitor’ tight binding to that isoenzyme. These results suggest that R. dominica uses RdA70 to bind large amounts of wheat α-amylase inhibitors than RdA79 and RdA90 as a physiological defense mechanism.

Callosobruchus maculatus (Fab.) is the principal pest of the stored chickpea. The larvae of this insect feed on the grain, causing considerable damage that produces qualitative and quantitative losses. For control of this species, pesticides such as phosphine and methyl bromide have been used; the latter was withdrawn from use due to the reduction of the ozone layer. Therefore, it is important to develop novel, safe, and economical control alternatives such as Controlled Atmospheres (CA). In this study, the mortality was determined on four developmental states of C. maculatus, employing CA at different concentrations (50, 70, and 90% CO2 with 10, 6, and 3% O2, respectively) during 48, 72, and 120 h. 100% mortality of adult insects was observed with 50% CO2 at 48 h. Cases of third instar exhibit higher resistance to CA than adults, with 18.9% mortality at 48 h. There were no significant differences in tests on water absorption, cooking time, texture, and color. Finally, the chickpea germination obtained was 93.5% with 90% CO2 exposure during 120 h. In this latter treatment, significant differences were not presented between control and CA treatments. On comparison of means of vigor, the treatments are favored in terms of weight, rootlet number, plumule and radicle growth with the increase of CO2 concentration and exposure time. In conclusion, the effect of CA was lethal on C. maculatus, did not affect chickpea quality, and it favored chickpea vigor.

National Council of Science and Technology (CONACyT) [INFR-226208-2014, INFR-255791-2015]; CONACYT

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.

Se ha implementado el uso de nuevas nanoestructuras y tecnicas que permitan producir nanoparticulas para su aplicacion en diversos sectores con la finalidad de mejorar los procesos e incrementar la productividad. Una de estas es el metodo de electrohilado o electrospinning, teniendo la caracteristica de ser sencillo, de bajo costo y utilizar una gran variedad de materiales, convirtiendolo en uno de los mas utilizados. Las estructuras obtenidas poseen caracteristicas unicas, entre ellas su gran area de contacto y alta porosidad. Debido a estas propiedades, las nanofibras presentan gran interes para ser aplicadas en diferentes areas, como son la biomedica, textil y de alimentos obteniendo resultados beneficos.