Beta-carotene isomer composition of sub- and supercritical carbon dioxide extracts. Antioxidant activity measurement

In the present work sub- and supercritical extraction conditions using carbon dioxide were studied in order to obtain extracts with different compositions from the green microalgae Dunaliella salina. Different compositions of beta-carotene isomers were identified in the extracts by using HPLC-DAD. Also, antioxidant activity of the extracts was measured using a TEAC assay. An experimental design was applied considering two factors, extraction pressure and temperature, in a wide range of values, trying to maximize the extraction yield. Higher yields were obtained at high pressures and low temperatures, that is, at higher CO2 densities. Attempts were made to correlate the antioxidant activity of the extracts with their chemical composition by means of principal component analysis. A certain relationship was found between their antioxidant activity and the isomeric composition of beta-carotenes. As a result, an original equation is proposed to predict the antioxidant activity of extracts from D. salina in terms of the ratio 9-cis-beta-carotene/all-trans-beta-carotene, the concentration of alpha-carotene, and, especially, the concentration of 9-cis-beta-carotene.     

Enhancing Pinus pinea cone production by grafting in a non-native habitat

New Forests - Pinus pinea is an interesting species for its valued pine nuts. Despite the high demand for this nut, the species is mostly harvested from natural forests, because the time elapsed...     

Bird-mediated effects of pest control services on crop productivity: a global synthesis

Journal of Pest Science - Birds provide important ecosystem services in many ecosystems, including important pest control effects on productive systems. The typically low bird diversity observed in...     

Implications of landscape configuration on understory forage productivity: a remote sensing assessment of native forests openings

Agroforestry Systems - Sound management of native forests used for cattle grazing requires understanding the dynamics of forage productivity in the openings. Despite their importance, forage...     

Evidence for widespread Leishmania infantum infection among wild carnivores in L. infantum periendemic northern Spain

Leishmania spp. infection was investigated in tissue samples of wild carnivores from the Spanish Basque Country (BC), by PCR and DNA sequencing. The region is at the northern periphery of Leishmania infantum endemic Iberian Peninsula and infection in the dog (reservoir) or other species has not been previously reported. Leishmania kinetoplast DNA was detected by real-time PCR (rtPCR) in 28% (44/156) of animals. Specifically, in 26% of Eurasian badgers (n = 53), 29% of foxes (n = 48), 29% of stone martens (n = 21) and in 25–50% of less numerous species including genets, wild cats, pole cats, European mink and weasels. Infected animals particularly badgers, were most prevalent in the southernmost province of the BC (Araba) in areas dominated by arable land. Subsequent amplification and sequencing of a fragment of the rRNA internal transcribed spacer 2 (ITS2) from a subset of rtPCR positives samples confirmed the species as L. infantum, showing a high sequence homogeneity with ITS2 sequences of L. infantum from dogs and humans from southern Spain. In summary, this study reports for the first time L. infantum infection in wild carnivores from the BC including in stone martens, pole cats and minks in which infection has not been previously described. It supports the need to study infection in dogs and people in this region and is an example of the value of infection surveillance in wildlife to assess potential risks in the domestic environment and their role in spreading infections in non-endemic areas.     

First report of Enterocytozoon bieneusi from dairy cattle in Argentina

Fecal specimens were obtained from a total of 70 dairy calves less than two months old on 11 municipalities in Buenos Aires, Argentina. After removal of fecal debris by sieving and sucrose flotation, specimens were subjected to PCR to detect the presence of Enterocytozoon bieneusi. PCR revealed a 14.3% of prevalence for E. bieneusi with 10 positive calves from 7 municipalities. Gene sequence analysis conducted in all samples positives by PCR revealed the presence of six genotypes; four previously reported in cattle as well as humans (D, I, J, and BEB4), one never reported in cattle before but previously reported in humans (EbpC), and one novel genotype (BEB10). These results constitute the first molecular characterization of E. bieneusi in Argentina, and suggest a potential risk of zoonotic transmission in this area.     

Treatment of a femoral fracture with a titanium locking compression plate distal femur (LCP‐DF) in a young donkey

A closed complete mid‐diaphyseal spiral fracture of the left femur in a one‐year‐old donkey was treated with a 4.5 mm titanium locking compression plate distal femur (LCP‐DF)¹. This plate was originally manufactured for human orthopaedics, primarily for femoral osteosynthesis. The LCP‐DF¹ has a distal head plate that was advantageous in this case because the distal fragment was smaller. Post operative radiographs showed optimal femoral reconstruction and a callus was present 3 weeks after surgery. The donkey was sound at the walk and trot 2 months after surgery. Radiographs taken 5 months after surgery showed stable implants and complete healing without complications.     

Vegetative propagation of the carrageenophytic red alga Gigartina skottsbergii Setchell et Gardner: Indoor and field experiments

The carrageenophytic red alga Gigartina skottsbergii presents several biological constraints for its cultivation such as restricted temporal availability and high spore mortalities that affect the development of its mass cultivation. For this reason, research to develop alternative propagation methods has been undertaken. Previous laboratory studies demonstrated that manipulating temperature, light and nutrients could enhance healing and regeneration of this seaweed. In this study nursery and field experiments were undertaken to establish the possibility to regrow G. skottsbergii in conditions similar to those applied in mass cultivation practices. Frond fragments and rhizoids were tested as alternative ways to obtain new plants. Our results indicate that regeneration occurs in the field, and can be managed in nursery conditions. The addition of a nitrogen source enhances the growth from 0.6 to 1.0% d^− 1 of the healed fragments and the use of a photon flux density above 50 μmol m^− 2 s^− 1 increases the growth rate but decrease the survival of the explants. Explants can be transferred to field conditions and grow at similar rates to those registered in the nursery (0.5% d^− 1). It is also possible to propagate rhizoids of G. skottsbergii and it seems that the attachment of a frond portion to the substratum, enhanced its survival and regeneration capacity. Finally, this study demonstrated that rhizoids attached to rocks can regenerate complete plants in nature, a feature which could be a useful for developing a sustainable harvesting methodology.     

Potential longevity (Ki) of malting barley (Hordeum vulgare L.) grain lots relates to their degree of pre-germination assessed through different industrial quality parameters

Barley (Hordeum vulgare L.) grain germination is required to perform the malting process. Maintenance of barley seed viability during storage is crucial for the malt industry; and modern cultivars are bred for rapid grain dormancy release after physiological maturity. Low dormancy level combined with rain close to harvest induces pre-germination/pre-harvest sprouting damage. Pre-germination might not affect viability in the short term after harvest, but it could reduce potential longevity (K_i) of a barley seed lot. K_i value is inherent for each barley lot; however, its determination is time-consuming which precludes its assessment at an industrial scale. In this study we sought quantitative relationships between K_i and the pre-germination degree of barley grain lots, assessed through quality tests routinely performed by malthouses [Falling Number (FN), α-Amylase Activity and Carlsberg]. Field pre-germinated lots from one old barley cultivar (Quilmes Palomar) and artificially pre-germinated lots from major varieties currently grown in Argentina were used. Associations between K_i and values obtained from all quality tests analysed were found for Q. Palomar. However, FN was the parameter that yielded the best and simplest explanation of K_i variability. A significant positive linear K_i -FN relationship was also obtained for each modern barley cultivar.