Development of transgenic fungi that kill human malaria parasites in mosquitoes

Metarhizium anisopliae infects mosquitoes through the cuticle and proliferates in the hemolymph. To allow M. anisopliae to combat malaria in mosquitoes with advanced malaria infections, we produced recombinant strains expressing molecules that target sporozoites as they travel through the hemolymph to the salivary glands. Eleven days after a Plasmodium-infected blood meal, mosquitoes were treated with M. anisopliae expressing salivary gland and midgut peptide 1 (SM1), which blocks attachment of sporozoites to salivary glands; a single-chain antibody that agglutinates sporozoites; or scorpine, which is an antimicrobial toxin. These reduced sporozoite counts by 71%, 85%, and 90%, respectively. M. anisopliae expressing scorpine and an [SM1](8):scorpine fusion protein reduced sporozoite counts by 98%, suggesting that Metarhizium-mediated inhibition of Plasmodium development could be a powerful weapon for combating malaria.     

Rubidium-87/strontium-87 age of juvinas basaltic achondrite and early igneous activity in the solar system

A (4.60+/-0.07)x10(9) year internal isochron has been drawn for the achondrite Juvinas by the rubidium-87/strontium-87 method. Earlier petrographic investigation of achondrites supplemented by a new ion microprobe study of Juvinas strongly suggest an igneous origin for this class of meteorites. The results thus indicate that igneous activity may have rapidly followed the formation of the achondrites' parent body 4.6x10(9) years ago.     

Integrating GIS and homing experiments to study avian movement costs

Forest cover reduction may affect movements of forest animals, but resistance to animal movements in and out of forests remains unknown despite its importance for modelling. We tested whether ovenbird (Seiurus aurocapilla), a forest-interior songbird, responds similarly to the amount of forest cover while moving locally (~2 km) and over entire landscapes (~25 km). We compared spatially-explicit simulations to field data to address the issue of resistance to movement in open areas. We caught, banded and translocated 143 territorial males 0.8–27 km away from their territory early in the breeding season. Seventy-eight percent and 50% of translocated males returned (homed) within 10 days following “local” and “landscape” translocations respectively. Independent of translocation distance, homing times increased with decreasing forest in the landscape. With a Geographic Information System (GIS), we simulated “least-cost” paths that homing ovenbirds would ideally take, when resistance to movement in open areas ranged 1–1000 times the resistance to movement in forest. The length, the cumulative cost, and variability of simulated least-cost movement paths increased with increasing resistance in open areas. With landscape translocations, least-cost path length explained homing time better than Euclidean distance, and based on an information-theoretic approach, resistance to movement was estimated to be 27 times greater in open areas than in forests (95% confidence interval: 16–45). However, least-cost path length did not perform better than Euclidean distance with local translocations, and the cumulative cost of least-cost paths was not associated to homing time in either translocation scale. We conclude that resistance to animal movements in open areas can be addressed by a combination of GIS modelling and translocation experiments, and is between one and two orders of magnitude greater than resistance to movements in forests, in the case of ovenbirds.     

Edge effect and matrix influence on the nest survival of an old forest specialist,the Brown Creeper (<Emphasis Type="Italic">Certhia americana</Emphasis>)

Conservation strategies should be based on a solid understanding of processes underlying species response to landscape change. In forests fragmented by agriculture, elevated nest predation rates have been reported in many forest bird species, especially near edges. In intensively-managed forest landscapes, timber harvesting might also be associated with negative edge effects or broader “context” effects on some species when the matrix provides additional resources to their major nest predators. In this study, we hypothesized that proximity to a forest edge and proportion of cone-producing plantations will increase nest predation risk in fragments of relatively undisturbed forest. We focused on the Brown Creeper (Certhia americana), an indicator species of late-seral forests. We compared habitat configuration and composition at four spatial scales (0.14, 0.5, 1 and 2 km) around 54 nests and related daily nest survival rate to the distance to the nearest forest edge, mean patch size of late-seral forest (r = 141 m), proportion of non-forested lands (r = 141 m), density of maintained roads (r = 1 km), proportion of cone-producing spruce plantations (r = 2 km), and year. The best model included distance to the nearest edge and proportion of cone-producing plantations. Distance of nests to the nearest edge was the best individual predictor of daily nest survival. A larger sample of nests showed a significant threshold in distance to the nearest forest edge; nests located at least 100 m away were more likely to fledge young. These results suggest that even in managed forest landscapes, matrix effects can be important and some bird species may exhibit negative edge effects.     

Effect of a new thermal treatment in combination with saprobic fungal incubation on the phytotoxicity level of alperujo

Byproducts generated from food industries, such as olive oil mills, have been studied to decrease harmful pollution and their environmental consequences. In this work, a new thermal pretreatment and saprobic fungal incubation to detoxify alperujo (two-phase olive mill waste) have been evaluated in view of its use as fertilizer in agriculture. The sequential use of both methods simplifies the thermal conditions and incubation times of the fungal treatment. Optimization of the thermal treatment from 150 to 170 °C for 45 and 15 min, respectively, reduced the incubation time with Coriolpsis rigida from 20 to 10 weeks needed to reduce phytotoxic effects on tomato plants. Therefore, the combination of thermal and biological treatments will allow the development of the potential benefits of alperujo to improve nutrients in agricultural soil.     

Quantification of 4-methylimidazole in class III and IV caramel colors: validation of a new method based on heart-cutting two-dimensional liquid chromatography (LC-LC)

4-Methylimidazole (4MeI) is a nitrogen compound formed during the manufacture of class III and IV caramel colors. The European Commission has limited its content to 250 ppm. Two methods were compared to perform 4MeI quantification in caramels. The first one, currently used and considered to be the reference method, consists of a hot extraction of caramel color with dichloromethane and an analysis of the acetyl derivative of the extract by gas chromatography coupled to mass spectrometry (GC-MS). The second method is based on the heart-cutting two-dimensional liquid chromatography technique (LC-LC) to directly separate 4MeI from the other components present in caramel color sample (diluted in water) in <30 min. The accuracy profile validation method and the comparison between the results obtained with the two methods show that the new and completely automated LC-LC method is usable to quantify 4MeI in caramels.     

In vitro digestibility of α-casozepine, a benzodiazepine-like peptide from bovine casein, and biological activity of its main proteolytic fragment

α-Casozepine is a peptide, corresponding to the sequence 91-100 of the bovine α(s1)-casein, displaying anxiolytic activity in the rat. The α(s1)-casein tryptic hydrolysate containing this peptide decreases stress effects after oral administration in various species including man. Therefore, the stability of this peptide toward gastric and pancreatic proteases has been assessed by using pepsin, chymotrypsin/trypsin, Corolase PP, pepsin followed by chymotrypsin/trypsin or pepsin followed by Corolase PP. α-Casozepine was slowly degraded by chymotrypsin, much more sensitive to pepsin and Corolase PP but not completely destroyed after 4 h kinetics. The bonds in the region 91 to 95 of the α-casozepine were totally resistant to hydrolysis by all studied proteases. Surprisingly, a fragment, corresponding to the sequence 91-97 and found in all the hydrolysis media in significant amount, possessed an anxiolytic activity in three behavioral tests measuring this parameter. This peptide could participate in the in vivo activity of α-casozepine.     

Profiling LC-DAD-ESI-TOF MS method for the determination of phenolic metabolites from avocado (Persea americana)

A powerful HPLC-DAD-ESI-TOF MS method was established for the efficient identification of the chemical constituents in the methanolic extracts of avocado (Persea americana). Separation and detection conditions were optimized by using a standard mix containing 39 compounds belonging to phenolic acids and different categories of flavonoids, analytes that could be potentially present in the avocado extracts. Optimum LC separation was achieved on a Zorbax Eclipse Plus C18 analytical column (4.6×150 mm, 1.8 μm particle size) by gradient elution with water+acetic acid (0.5%) and acetonitrile as mobile phases, at a flow rate of 1.6 mL/min. The detection was carried out by ultraviolet-visible absorption and ESI-TOF MS. The developed method was applied to the study of 3 different varieties of avocado, and 17 compounds were unequivocally identified with standards. Moreover, around 25 analytes were tentatively identified by taking into account the accuracy and isotopic information provided by TOF MS.     

Relationships between earthworm communities and burrow numbers under different land use systems

This study addresses the influence of three different land use systems (continuous maize, pasture/maize rotation, permanent pasture) on the relationships between earthworm populations and the number of earthworm burrows quantified in a soil profile. Quantified burrows were limited to those observable by the naked eye (i.e. >2 mm in diameter) and enumerated earthworms were limited to those which could have created the observable burrows (i.e. >0.3 g).The results were combined with data from the literature coming from different geographical regions. This study showed that earthworm abundance decreased with the increasing land management intensity (maize crop vs. pasture), while the number of burrows could be higher or similar under maize compared to pasture. Under maize, despite lower earthworm abundance and the annual destruction of the burrows by tillage, the number of burrows was almost as high as under pasture. This absence of a relationship between burrow numbers and earthworm abundance was observed in the soil profile and for each layer of the profile for each land use system. Furthermore, the burrow number/m^?2 per earthworm strongly varied depending on land use and was far higher under maize when compared to pasture (74 vs. 7). Therefore, a power-law type relationship was clearly established between burrow number/m^?2 per earthworm and earthworm abundance. This power type relationship was also observed when including data from the literature although it followed a different mathematical model. These results were explained by (i) increased earthworm burrowing activity (i.e. an increase in the number of burrows produced by each earthworm) under maize, and (ii) the dynamics of burrow number under pasture (i.e. decreased burrowing activity and burrow destruction process); both results of food accessibility combined with inter-individual competition. The results of the study suggest that farmers should not use the number of pores as an indicator of earthworm abundance, but as an indicator of earthworm activity, which could be integrated in an indicator of soil quality.     

Analytical and sensorial characterization of the aroma of wines produced with sour rotten grapes using GC-O and GC-MS: identification of key aroma compounds

In the present work, the aroma profiles of wines elaborated from sound and sour rot-infected grapes as raw material have been studied by sensory analysis, gas chromatography-olfactometry (GC-O), and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the odor volatiles most likely associated with this disease. The effect of sour rot was tested in monovarietal wines produced with the Portuguese red grape variety Trincadeira and in blends of Cabernet Sauvignon and sour rotten Trincadeira grapes. Wines produced from damaged berries exhibited clear honey-like notes not evoked by healthy samples. Ethyl phenylacetate (EPhA) and phenylacetic acid (PAA), both exhibiting sweet honey-like aromas, emerged as key aroma compounds of sour rotten wines. Their levels were 1 order of magnitude above those found in controls and reached 304 and 1668 μg L(-1) of EPhA and PAA, respectively, well above the corresponding odor thresholds. Levels of γ-nonalactone also increased by a factor 3 in sour rot samples. Results also suggest that sour rot exerts a great effect on the secondary metabolism of yeast, decreasing the levels of volatiles related to fatty acids and amino acid synthesis. The highest levels of γ-decalactone of up to 405 μg L(-1) were also found in all of the samples, suggesting that this could be a relevant aroma compound in Trincadeira wine aroma.