In the present study, the characterization and properties of silver nanoparticles from Yucca shilerifera leaf extract (AgNPs) were investigated using UV–visible spectroscopic techniques, zeta potential, and dynamic light scattering. The UV–visible spectroscopic analysis showed the absorbance peaked at 460 nm, which indicated the synthesis of silver nanoparticles. The experimental results showed silver nanoparticles had Z-average diameter of 729 nm with lower stability (195.1 mV). Additionally, our dates revealed that AgNPs showed broad spectrum antagonism (p ≤ .05) against Fusarium solani (83.05%) and Macrophomina phaseolina (67.05%) when compared to the control after nine days of incubation. Finally, AgNPs from leaf extracts of Y. shilerifera may be used as an agent of biocontrol of microorganism of importance. However, further studies will be needed to fully understand the agronanotechnological potentialities of AgNPs from Yucca schidigera.

Currently, emerging alimentary alternatives are growing, leading to the consumption of natural products including bio, fermented, and traditional foods. The studies over functional properties of food matrices and their derived compounds have resulted in the development of new functional alimentary items. However, most of the population still has limited access to, and information about, suitable foods. Analyzing traditional fermented products, we found fermented food matrices containing beneficial bacteria, with the possibility of exerting effects on different substrates enhancing the bioavailability of short-chain fatty acids (SFCAs), antioxidants, among other food-derived products. Maize (Zea mays L.), agave varieties, nopal (Opuntia ficus-indica), and beans (Phaseolus vulgaris L.) were key foods for the agricultural and nutritional development of Mesoamerica. We believe that the traditional Mexican diet has relevant ingredients with these functionalities and their association will allow us to develop functional food suitable for each population and their current needs. In this review, the functional properties of maize, agave, nopal, and frijol are detailed, and the functional food innovation and development opportunities for these food matrices are analyzed, which may be an important precedent for future basic and applied research.

ABSTRACT. Extraction of high-quality genomic DNA for PCR amplification from filamentous fungi is difficult because of the complex cell wall and the high concentrations of polysaccharides and other secondary metabolites that bind to or co-precipitate with nucleic acids. We developed a modified sodium dodecyl sulfate/phenol protocol, without maceration in liquid nitrogen and without a final ethanol precipitation step. The A 260/280 absorbance ratios of isolated DNA were approximately 1.7-1.9, demonstrating that the DNA fraction is pure and can be used for analysis. Additionally, the A 260/230 values were higher than 1.6, demonstrating negligible contamination by polysaccharides. The DNA isolated by this protocol is of sufficient quality for molecular applications; this technique could be applied to other organisms that have similar substances that hinder DNA extraction. The main advantages of the method are that the mycelium is directly recovered from culture medium and it does not require the use of expensive and specialized equipment.

higher than the values detected in P. juliflora Nevertheless, the cadmium concentration in foliar tissues of P. juliflora was significantly higher than P. glandulosa after 96 h of exposure to Cu 2+ or Cd 2+. Therefore, future studies are necessary to elucidate the effects of heavy metals on the biosynthesis of flavonoids and participation of these compounds in the reduction of metal toxicity in Prosopis species.

Phenacoccus solenopsis has been recognized as an aggressively invasive species on cotton plants in different countries. This study was conducted to investigate the effect of green synthesized Cu/Zn-nanoparticles using aqueous leaf extract of Prosopis juliflora (mezquite) against P. solenopsis. The scanning electron microscope (SEM) showed bimetallic nanoparticles of Cu/Zn-NPs with spherical shape with varying size of 74.33 nm to 59.46 nm. More than 30% mortality of P. solenopsis was observed with Cu/Zn-nanoparticles (100 ppm) at 96 hours after treatment. Negligible mortality of P. solenopsis was recorded with Cu/Zn solution (100 ppm) and aqueous P. juliflora extracts. The results of the viability test for Cu/Zn-nanoparticles of P. juliflora showed a significant reduction of the cell viability by 50% in insect exposed to Cu/Zn-nanoparticles-P.juliflora. Therefore studies about nanotoxicity of Cu/Zn-NPs of P.juliflora are needed to reveal the mechanism of toxicity this phytonanoparticles in P.solenopsis.

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Feathers are the most prevalent agricultural waste generated by chicken farms, polluting the environment and wasting protein resources as a result of the accumulation of large amounts of feathers. Therefore, keratinase-producing microorganisms represent a promising potential technique for the degradation of feather waste. Streptomyces netropsis A-ICA and Bacillus subtilis ALICA, previously isolated from the rhizosphere of desert plants (Larrea tridentata and Prosopis juliflora) respectively, were assessed for their feather-degradation ability. Keratinase activity was optimized using various parameters, including incubation time, pH, temperature, and feather concentration. The maximum keratinase activity of S. netropsis A-ICA and B. subtilis ALICA (113.6 ± 5.1 and 135.6 ± 4.1 U/mL) was obtained at the 5th and 3rd day of incubation with initial pH of 7.0 and 7.5 at 25 and 30 °C, and 1% (w/v) of chicken feather, respectively. Under the optimized conditions, the concentration of soluble protein in the feather hydrolysate reached 423.3 ± 25 and 565.3 ± 7.7 µg/mL, with feathers weight loss of 84 ± 2 and 86± 1.5% by S. netropsis A-ICA and B. subtilis ALICA, respectively. The highest disulphide bond reductase activity reached 10.7 ± 0.4 and 1.96 ± 1.1 U/mL, after five and three days of inoculation with S. netropsis A-ICA and B. subtilis ALICA, respectively. Furthermore, the antioxidant activity of feather protein hydrolysate obtained by S. netropsis A-ICA and B. subtilis ALICA was evaluated using DPPH radical-scavenging activity, which exhibited a significant antioxidant potential with an IC50 value of 0.8 and 0.6 mg/mL. The 3D models of detected keratinases in both strains showed high similarity with subtilisin family. Further, the docking results clarified the importance of GSG and VVVFTP domains in B. subtilis and beta-keratin, respectively. The present study revealed the keratinolytic potential of S. netropsis A-ICA and B. subtilis ALICA in chicken feather degradation, which have potential application value and may be exploited as supplementary protein and antioxidant in animal feed formulations.

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