Over the last few years, the green synthesis of nanoparticles (NPs) using plant extracts has emerged as a promising methodology for the fabrication of metallic NPs (especially silver, copper, and gold NPs), as it involves an easy, fast, low-cost, and environmentally friendly bioprocess. However, many factors affect the sizes and morphologies of NPs biosynthesized by this method, including the nature of the plant extract, among others. Therefore, the green synthesis of metal NPs with defined stability, size, and morphology distribution remains under evaluation. In the present study, we propose aqueous extracts from the endemic-medicinal plant Budleja globosa ("Matico") as an efficient bioproduct for the green synthesis of silver NPs (AgNPs). Experimental results indicate that room temperature, low concentrations of leaf extracts of B. globosa, and silver nitrate salt were sufficient to biosynthesize AgNPs with uniform size (16 nm) and shape distribution (spherical).

This study presents the first application of an in vivo alkaline comet assay using haemocytes of Drosophila melanogaster larvae. These cells, which play a role similar to that of mammalian blood, can be easily obtained and represent an overall exposure of the treated larvae. To validate the assay, we evaluated the response of these cells to three well-known mutagenic agents: ethyl methanesulfonate (EMS), potassium dichromate (PD), and gamma radiation (γ-irradiation). Third-instar Drosophila larvae were exposed to different concentrations of EMS (1, 2, and 4 mM) and PD (0.5, 1, and 2.5 mM) and to different doses of γ-irradiation (2, 4, and 8 Gγ). Subsequently, haemolymph was extracted from the larvae, and haemocytes were isolated by centrifugation and used in the comet assay. Haemocytes exhibited a significant dose-related increase in DNA damage, indicating that these cells are clearly sensitive to the treatments. These results suggest that the proposed in vivo comet test, using larvae haemocytes of D. melanogaster, may be a useful in vivo assay for genotoxicity assessment.

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Copper and nickel nanoparticles (Cu-NPs and Ni-NPs, respectively) are used in a variety of industrial applications, such as semiconductors, catalysts, sensors, and antimicrobial agents. Although studies on its potential genotoxicity already exist, few of them report in vivo data. In the present study we have used the wing-spot assay in Drosophila melanogaster to determine the genotoxic activity of Cu-NPs and Ni-NPs, and these data have been compared with those obtained with their microparticle forms (MPs). Additionally, a complete physical characterization of NPs using transmission electronic microscopy (TEM), dynamic light scattering (DLS), and laser Doppler velocimetry (LDV) techniques was also performed. Results obtained with Cu-NPs and Cu-MPs indicate that both failed to induce an increase in the frequency of mutant spots formation in the wings of the adults, suggesting a lack of genotoxicity in somatic cells of D. melanogaster. However, when Ni-NPs and Ni-MPs were evaluated, a significant increase of small single spots and total mutant spots was observed only for Ni-NPs (P<0.05) at the highest dose assessed. Thus, the genotoxicity of Ni-NPs seem to be related to their nanoscale size, because no genotoxic effects have been reported with their microparticles and ions. This study is the first assessing the in vivo genotoxic potential of Cu-NPs and Ni-NPs in the Drosophila model.

In the present study the diet of the barn owl Tyto alba was analysed in the ecosystem of Pampa del Tamarugal, in the Atacama Desert, northern Chile. The area is characterised by extremely dry conditions, and relatively homogeneous and poor vegetation, dominated mainly by tamarugo forests (Prosopis tamarugo). The results indicated that small mammals were the greatest proportion (76.2%) in the diet of the barn owl, which predated only four species, of which the rodent Phyllotis darwini (approximately 62%) represented the major proportion. Nevertheless, reptiles and arthropods were also relevant prey for the barn owl, with a proportion of 5% and 15.1%, respectively. The general dietary composition of the tamarugos barn owl showed a wide-ranging diet pattern, characterised mainly by a poor diversity of small mammals and a significant consumption of reptiles and arthropods, in contrast to the sites in the central region and south Chile, where the diet included a greater diversity of small mammals, especially rodents. This pattern might reflect the conditions of extreme aridity, and low primary productivity in the ecosystem of Pampa del Tamarugal, restricting the abundance and diversity of the preferential prey (e.g. rodents). Hence, T. alba tends to increase its trophic diversity, adding other kinds of alternative prey to compensate for the low proportion of preferential prey available in the field.