Leaf-cutting ants are the most important pests in several cropping systems in the Neotropics. Granulated baits containing active ingredients, considered hazardous by the Stockholm Convention, are the ...usual method to control these ants. Isocycloseram is a new insecticide molecule with high safety margin for mammals, but without registration for the ants in general. Thus, this study investigated the effectiveness of granulated baits with isocycloseram in leaf-cutting ants control under laboratory and field conditions. Initially, the mortality of Atta sexdens workers, fed with dehydrated citrus pulp paste containing different concentrations of isocycloseram was evaluated in the laboratory for 21 days, for toxicological classification. Subsequently, the loading, devolution, and incorporation of baits with different concentrations of isocycloseram and the mortality of A. sexdens colonies were evaluated in the laboratory. After that, the percentages of loading and devolution of baits, foraging activity, and colony mortality treated with 0.05, 0.1, 0.2, and 0.3% of isocycloseram were evaluated for the species A. sexdens, A. laevigata, and Acromyrmex lundii in field conditions. All concentrations of isocycloseram killed more than 15% of ants in 24 h and more than 90% in 21 days in the laboratory, being classified as a fast-acting and highly effective active ingredient. Baits with 0.001 to 0.03% of isocycloseram were highly loaded and exhibited low rate of devolution. The mortality of A. sexdens colony was higher at concentrations between 0.075 and 0.3%, in the laboratory. Baits containing isocycloseram at concentrations of 0.2 and 0.3% were highly loaded, presented low devolution rates, and were highly efficient in controlling A. sexdens, A. laevigata, and A. lundii in the field, at dosages of 6, 10, and 12 g/m² of nest. This is the first report of the use of isocycloseram against leaf-cutting ants, contributing to the development of efficient and toxicologically safer ant baits.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT
In this work, we evaluated the fermentative performance and metabolism modifications of a second generation (2G) industrial yeast by comparing an industrial condition during laboratory and ...industrial scale fermentations. Fermentations were done using industrial lignocellulosic hydrolysate and a synthetic medium containing inhibitors and analyses were carried out through transcriptomics and proteomics of these experimental conditions. We found that fermentation profiles were very similar, but there was an increase in xylose consumption rate during fermentations using synthetic medium when compared to lignocellulosic hydrolysate, likely due to the presence of unknown growth inhibitors contained in the hydrolysate. We also evaluated the bacterial community composition of the industrial fermentation setting and found that the presence of homofermentative and heterofermentative bacteria did not significantly change the performance of yeast fermentation. In parallel, temporal differentially expressed genes (tDEG) showed differences in gene expression profiles between compared conditions, including heat shocks and the presence of up-regulated genes from the TCA cycle during anaerobic xylose fermentation. Thus, we indicate HMF as a possible electron acceptor in this rapid respiratory process performed by yeast, in addition to demonstrating the importance of culture medium for the performance of yeast within industrial fermentation processes, highlighting the uniquenesses according to scales.
Using integrative analysis of transcriptome and proteome data to assess differences in how yeast perform under laboratory and industrial scales and conditions for 2G ethanol fermentation.
In sugarcane biorefineries, energy integration plays a fundamental role regarding by-product destination and final sales profitability. In biorefineries, the by-product of the sugar/ethanol ...production process – sugarcane bagasse – can be burned in boilers to produce steam to supply the thermal demands of the plant. Normally, the quantity of bagasse from the plant exceeds the quantity necessary for supplying the energy requirements of the plant. This surplus can be used for either (i) additional electricity production and selling to the grid or (ii) second-generation (2G) ethanol production. To maximize profit, the plant should be flexible to produce either electricity or 2G ethanol according to the current market prices of these products. In this work, an approach is presented for designing a flexible heat exchanger network (HEN) based on a multiperiod synthesis. It involves assessing probabilities of occurrence for different bagasse use scenarios. These values are obtained from a pinch-based approach for screening optimal heat integration in a range of ethanol/electricity prices. A multiperiod HEN synthesis problem is then solved with variable flow rates. Results show that maximum bagasse diverted to 2G ethanol production is increased from 66% to 77% with the new HEN compared to the original design considered.
•Sugarcane biorefinery produces first- and second-generation ethanol and electricity.•Heat integration is crucial in bagasse destination and profitability of the plant.•The fluctuation of ethanol and electricity prices demands flexible plants.•Probabilities of different bagasse use scenarios are based on historical prices.•Multiperiod HEN increases in 11% the possibility of producing 2nd-generation fuel.
Most CRISPR/Cas9 applications in yeast rely on a plasmid-based expression of Cas9 and its guide RNA (gRNA) containing a 20-nucleotides (nts) spacer tailored to each genomic target. The lengthy ...assembly of this customized gRNA requires at least 3–5 days for its precloning in Escherichia coli, purification, validation, and cotransformation with Cas9 into a yeast strain. Here, we constructed a series of 12 EasyGuide plasmids to simplify CRISPR/Cas9 applications in Saccharomyces cerevisiae. The new vectors provide templates for generating PCR fragments that can assemble up to six functional gRNAs directly into yeasts via homologous recombination between the 20-nts spacers. By dispensing precloning in E. coli, yeast in vivo gRNA assembly significantly reduces the CRISPR/Cas9 experimental workload. A highly efficient yeast genome editing procedure, involving PCR amplification of gRNAs and donors, followed by their transformation into a Cas9-expressing strain, can be easily accomplished through a quick protocol.
Abstract Bacterial wilt, caused by Ralstonia pseudosolanacearum (Rpsol) and R . solanacearum (Rsol), poses a significant challenge to solanaceous plant cultivation worldwide, particularly in tropical ...and subtropical regions. Even though Brazil is recognized as one of the centres of origin and diversity of Rsol, in certain regions of this large country there is an emerging prevalence of Rpsol in production fields. Therefore, this study aimed to comprehensively investigate the adaptive traits of Rpsol and Rsol using a polyphasic approach. A diverse collection of isolates from both species was assessed for their physiological, biochemical, ecological and pathogenic traits. Rsol isolates demonstrated greater adaptability to a broader range of temperature, salinity and pH. They also exhibited enhanced abilities in biofilm formation and bacteriocin production. Conversely, Rpsol isolates exhibited a broader utilization of carbon sources and displayed a wider spectrum of resistance to inhibitory substances. Moreover, they demonstrated higher infectivity towards different solanaceous hosts, showing a faster invasion and colonization process in the roots and stems of tomato plants compared to Rsol isolates. Based on our findings, we concluded that Rsol exhibited greater physiological and ecological adaptability, while Rpsol showed greater pathogenic and biochemical adaptability. These results suggest that the coexistence of both species is maintained through a balance of distinct traits within each species.
Plant pathogenic
Xanthomonas
species attack a wide range of agriculture crops and is capable of surviving on weeds. In this study,
Xanthomonas
strains obtained from weeds grown withing vegetable crop ...fields in the state of Pernambuco, Northeast Brazil, were identified. Bacterial colonies resembling
Xanthomonas
were obtained from
Aeollanthus suaveolens
(strain CCRMXe03),
Amaranthus lividus
(CCRMXe01 and CCRMXe02),
Sida glomerata
(CCRMXe04), and
Emilia fosbergii
(CCRMXe04). All weeds but
E. fosbergii
exhibited lesions on the leaves. Phylogenetic analysis of the
gyrB
and
rpoD
genes and PCR-specific assays allowed to identify
X
.
euvesicatoria
pv.
euvesicatoria
(CCRMXe01, CCRMXe02, CCRMXe03, and CCRMXe04) and
X
.
campestris
pv.
campestris
(CCRMXcc371). All strains but CCRMXe03 were pathogenic to its host of origin. All
X
.
euvesicatoria
pv.
euvesicatoria
strains were pathogenic to leaves and fruits of tomato and bell pepper. Two strains, CCRMXe03 and CCRMXe04, were capable of inducing soft rot in fruits. Amylolytic activity was found in all strains and two strains (CCRMXe03 and CCRMXe04) degraded pectate. Strain CCRMXcc371 was pathogenic to cabbage, kale, cauliflower, and broccoli. This work provides new knowledge of hosts for two important plant pathogenic bacteria for vegetable crops.
The identification of high-performance indicator taxa that combine practical feasibility and ecological value requires an understanding of the costs and benefits of surveying different taxa. We ...present a generic and novel framework for identifying such taxa, and illustrate our approach using a large-scale assessment of 14 different higher taxa across three forest types in the Brazilian Amazon, estimating both the standardized survey cost and the ecological and biodiversity indicator value for each taxon. Survey costs varied by three orders of magnitude, and dung beetles and birds were identified as especially suitable for evaluating and monitoring the ecological consequences of habitat change in our study region. However, an exclusive focus on such taxa occurs at the expense of understanding patterns of diversity in other groups. To improve the cost-effectiveness of biodiversity research we encourage a combination of clearer research goals and the use of an objective evidence-based approach to selecting study taxa.
•CrataBL, a natural compound, attenuates elastase-induced pulmonary inflammation.•CrataBL reduces oxidative stress responses induced by elastase.•CrataBL decreases lung emphysema in mice.•Potential ...therapeutic tool of CrataBL for COPD.
Chronic obstructive pulmonary disease (COPD) can lead to chronic and obstructive bronchitis and emphysema resulting in decreased bronchial lumen size.
This study evaluated the effect of CrataBL, a protein isolated from the bark of Crataeva tapia, on lung mechanics, inflammation, and remodeling after elastase-induced pulmonary alterations in mice.
The use of CrataBL led to decreased mechanical alterations, alveolar septum disruption (Lm), number of macrophage and neutrophil cells in the BALF, and TNF-α, MMP-9, MMP-12, TIMP-1, eNOS, and iNOS positive cells in the airways and alveolar walls compared to the animals in the ELA group. Moreover, a reduction in MUC-5-positive cells in the airway walls was observed. In conclusion, CrataBL attenuates changes in lung mechanics, inflammation, extracellular lung remodeling, and oxidative stress responses induced by the administration of elastase and decreased the volume fraction of isoprostane, collagen, and elastic fibers in the airways and alveolar walls compared to the animals in the ELA groups. Therefore, CrataBL is a potential therapeutic tool in the treatment of COPD.
Environmental and occupational exposure to benzene from fuels is a major cause for concern for national and international authorities, as benzene is a known carcinogen in humans and there is no safe ...limit for exposure to carcinogens. The objective of this study was to evaluate the genotoxic effects of chronic occupational exposure to benzene among two groups of workers: filling station workers (Group I) and security guards working at vehicles entrances (Group II), both on the same busy highway in Rio de Janeiro, Brazil. Sociodemographic data on the workers were evaluated; the concentration of benzene/toluene (B/T) in atmospheric air and individual
,
-muconic acid (
MA) and
-phenylmercapturic acid (
-PMA) were measured; oxidative stress was analyzed by catalase (CAT), glutathione
-transferase (GST), superoxide dismutase (SOD), thiol groups (THIOL) and malondialdehyde (MDA); genotoxicity was measured by metaphases with chromosomal abnormalities (MCA) and nuclear abnormalities, comet assay using the enzyme formamidopyrimidine DNA glycosylase (C-FPG), and methylation of repetitive element LINE-1,
and
genes. Eighty-six workers participated: 51 from Group I and 35 from Group II. The B/T ratio was similar for both groups, but Group I had greater oscillation of benzene concentrations because of their work activities. No differences in
MA and
-PMA, and no clinical changes were found between both groups, but linearity was observed between leukocyte count and
MA; and 15% of workers had leukocyte counts less than 4.5 × 10
cells L
, demanding close worker's attention. No differences were observed between the two groups for THIOL, MDA, MCA, or nuclear abnormalities. A multiple linear relationship was obtained for the biomarkers MCA and C-FPG. A significant correlation was found between length of time in current job and the biomarkers C-FPG, MCA, GST, and MDA. Although both populations had chronic exposure to benzene, the filling station workers were exposed to higher concentrations of benzene during their work activities, indicating an increased risk of DNA damage.
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