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Fermented crop straws by Trichoderma viride and Saccharomyces cerevisiae enhanced the bioconversion rate of Musca domestica (Diptera: Muscidae)
2019
Qi, Xuewei | Li, Zhihao | Akami, Mazarin | Mansour, Abdelaziz | Niu, Changying
Crop straw is an abundant renewable resource whose usage is limited due to its high cellulose, hemicellulose, and lignin contents. Here, Trichoderma viride, Saccharomyces cerevisiae, and Musca domestica were used to transform crop straws, and we investigated their impact on housefly rearing performance and optimized their utilization. The weights of cellulose, hemicellulose, and lignin in fermented crop straw diets significantly decreased after bioconversion by M. domestica larvae. The highest bioconversion rate was recorded in corn straw diet (16.19%), followed by wheat straw diet (10.31%) and wheat bran diet (8.97%). Similarly, high larval weight (yield) and pupation rate and fecundity and fertility rate were recorded in fermented crop straw diets composed of corn straw and wheat bran in 1:1 proportions. These results indicated that fermenting crop straw with T. viride and S. cerevisiae represented an efficient strategy that enhanced crop straw bioconversion and improved the rearing capacity of the housefly larvae. The resulting larvae could further be used as proteinaceous feed in poultry and aquaculture industries. Graphical abstract
显示更多 [+] 显示较少 [-]Dispersion, persistence, and stability of the biocontrol agent Penicillium frequentans strain 909 after stone fruit tree applications
2019
Guijarro, Belen | Larena, Inmaculada | Vilanova, Laura | Torres, Rosario | Balsells-Llauradó, Marta | Teixidó, Neus | Melgarejo, Paloma | De Cal, Antonieta
The capacity of dispersion, persistence, and stability from biocontrol agents is essential before these organisms can be developed into a commercial product. Interactions that microorganisms establish with stone fruit trees may be beneficial in the exploitation of trees in agriculture as crop production. The natural background levels of Penicillium frequentans strain 909 dispersion, persistence, and stability were assessed after tree applications and postharvest conditions. A fingerprinting-based approach to trace genetic stability of P. frequentans along stored time and its release in the field was developed. P. frequentans was successfully traced and discriminated. This strain was dispersed well in treated trees, persisting in the ecosystem up to 2 weeks and staying genetically stable after 36 months of storage. However, the dispersal of P. frequentans was very limited on around untreated trees and soil. P. frequentans dispersed randomly into the air, and its presence reduced from the first day to disappear completely at 15–21 days after application. Great losses of P. frequentans and its increased dispersal in open field conditions probably resulted from rainfall. Biological control strategies with Pf909 were discussed.
显示更多 [+] 显示较少 [-]Application of direct contact membrane distillation for saline dairy effluent treatment: performance and fouling analysis
2019
Abdelkader, Sana | Gross, Florian | Winter, Daniel | Went, Joachim | Koschikowski, Joachim | Geissen, S.-U. (Sven-Uwe) | Bousselmi, Latifa
Membrane distillation is getting increasing attention thanks to its advantages in terms of energy consumption and final permeate quality in addition to its resistance against highly corrosive media which forms an appealing solution for industrial wastewater treatment. Despite its advantages, one of the most challenging issues in direct contact membrane distillation (DCMD) is membrane fouling and wetting. In the present research work, saline dairy effluent discharged from hard cheese industry was pretreated by macrofiltration (MAF) and ultrafiltration (UF) and processed by DCMD to investigate the extent of the aforementioned issues. Effluents pretreated by UF have led the best process performance with stable flux values at different operating conditions. Fouling has occurred in all the experiments, though their effect on the flux behavior and membrane wetting was different from one feed to the other. Changing the flow rate and the temperature difference have affected slightly the membrane wettability for all feed qualities. In all experiments, the permeate has maintained a good quality with low electrical conductivity that did not exceed 70 μS/cm and low total organic carbon < 2 mg/L.
显示更多 [+] 显示较少 [-]Analysis of uranium removal capacity of anaerobic granular sludge bacterial communities under different initial pH conditions
2019
Zeng, Taotao | Li, Licheng | Mo, Guanhai | Wang, Guohua | Liu, Haiyan | Xie, Shuibo
The bacterial community of an anaerobic granular sludge associated with uranium depletion was investigated following its exposure to uranium under different initial pH conditions (pH 4.5, 5.5, and 6.5). The highest uranium removal efficiency (98.1%) was obtained for the sample with an initial pH of 6.5, which also supported the highest bacterial community richness and diversity. Venn diagrams visualized the decrease in the number of genera present in both the inoculum and the uranium-exposed biomass as the initial pH decreased from 6.5 to 4.5. Compared with the inoculum, a significant increase in the abundances of the phyla Chloroflexi and Proteobacteria was observed following uranium exposure. At initial pH conditions of 6.5 to 4.5, the proportions of the taxa Anaerolineaceae, Chryseobacterium, Acinetobacter, Pseudomonas, and Sulfurovum increased significantly, likely contributing to the observed uranium removal. Uranium exposure induced a greater level of dynamic diversification of bacterial abundances than did the initial pH difference.
显示更多 [+] 显示较少 [-]Correction to: Ginkgo biloba mitigates silver nanoparticles-induced hepatotoxicity in Wistar rats via improvement of mitochondrial biogenesis and antioxidant status
2019
Abd El-Maksoud, Eman M. | Lebda, Mohamed A. | Hashem, Aml E. | Taha, Nabil M. | Kamel, Maher A.
The original publication of this paper contains a mistake. The correct image of figure 3 is shown in this paper.
显示更多 [+] 显示较少 [-]Road traffic fatalities and its determinants in high-income countries: a continent-wise comparison
2019
Ali, Qamar | Yaseen, Muhammad Rizwan | Khan, Muhammad Tariq Iqbal
Road traffic accidents (RTAs) are accountable for 1.2 million deaths and road safety is the part of sustainable development goals, which aims to provide a safe, accessible, affordable, and sustainable transport system by 2030. This study discovered the nexus of road traffic fatalities (RTFs) with its determinants in Asia, Europe, and America. Vector error correction model established the causality of RTFs (Asia, Europe), urbanization (Asia), physicians (Asia, Europe), traffic law enforcement index (Europe, America), vehicles (America), and paved roads (America). Short-run bidirectional causality of RTFs was established with educational expenditures (Asia, Europe), GNI (Europe), and urbanization (Europe). The fall in RTFs was 0.359% (Europe) and 0.957% (America) for 1% rise in GNI. The RTFs were decreased by 0.498% (Europe) and 0.390% (America) due to 1% rise in urbanization. Education shows 0.952% reduction in RTFs in Europe. The 1% increase in the number of physicians causes 0.793% reduction in RTFs in America. The RTFs were increased by 0.617% and 1.705% for 1% rise in the number of vehicles in Asia and America. The fall in RTFs was 3.604%, 0.134%, and 0.950% for 1% rise in paved roads in Asia, Europe, and America, respectively. Results show a reduction of 0.744% (Asia), 0.712% (Europe), and 0.312% (America) in RTFs due to 1% increase in traffic law enforcement index. The governments of all countries should expand and improve their paved road network and increase the enforcement of traffic laws. The government should make strict traffic laws like regular inspection of vehicles, strict inspection for the driving license, electronic challan, and medical fitness of drivers. The government should ensure the medical checkup of drivers at subsidized rates. It is useful to include the traffic rules in the educational syllabus due to the significant role of law enforcement in road safety. The government should use different media channels for the awareness of the public about loss due to road accidents.
显示更多 [+] 显示较少 [-]Biochar as low-cost sorbent of volatile fuel organic compounds: potential application to water remediation
2019
Saiz-Rubio, Ruth | Balseiro-Romero, María | Antelo, Juan | Díez, Elena | Fiol, Sarah | Macías, Felipe
Pyrolysis of waste materials to produce biochar is an excellent and suitable alternative supporting a circular bio-based economy. One of the properties attributed to biochar is the capacity for sorbing organic contaminants, which is determined by its composition and physicochemical characteristics. In this study, the capacity of waste-derived biochar to retain volatile fuel organic compounds (benzene, toluene, ethylbenzene and xylene (BTEX) and fuel oxygenates (FO)) from artificially contaminated water was assessed using batch-based sorption experiments. Additionally, the sorption isotherms were established. The results showed significant differences between BTEX and FO sorption on biochar, being the most hydrophobic and non-polar contaminants those showing the highest retention. Furthermore, the sorption process reflected a multilayer behaviour and a relatively high sorption capacity of the biochar materials. Langmuir and Freundlich models were adequate to describe the experimental results and to detect general differences in the sorption behaviour of volatile fuel organic compounds. It was also observed that the feedstock material and biochar pyrolysis conditions had a significant influence in the sorption process. The highest sorption capacity was found in biochars produced at high temperature (> 400 °C) and thus rich in aromatic C, such as eucalyptus and corn cob biochars. Overall, waste-derived biochar offers a viable alternative to be used in the remediation of volatile fuel organic compounds from water due to its high sorption capacity.
显示更多 [+] 显示较少 [-]Oxidative stress in microbes after exposure to iron nanoparticles: analysis of aldehydes as oxidative damage products of lipids and proteins
2019
Semerád, Jaroslav | Moeder, Monika | Filip, Jan | Pivokonský, Martin | Filipová, Alena | Cajthaml, Tomáš
Due to their enhanced reactivity, metal and metal-oxide nanoscale zero-valent iron (nZVI) nanomaterials have been introduced into remediation practice. To ensure that environmental applications of nanomaterials are safe, their possible toxic effects should be described. However, there is still a lack of suitable toxicity tests that address the specific mode of action of nanoparticles, especially for nZVI. This contribution presents a novel approach for monitoring one of the most discussed adverse effects of nanoparticles, i.e., oxidative stress (OS). We optimized and developed an assay based on headspace-SPME-GC-MS analysis that enables the direct determination of volatile oxidative damage products (aldehydes) of lipids and proteins in microbial cultures after exposure to commercial types of nZVI. The method employs PDMS/DVB SPME fibers and pentafluorobenzyl derivatization, and the protocol was successfully tested using representatives of bacteria, fungi, and algae. Six aldehydes, namely, formaldehyde, acrolein, methional, benzaldehyde, glyoxal, and methylglyoxal, were detected in the cultures, and all of them exhibited dose-dependent sigmoidal responses. The presence of methional, which was detected in all cultures except those including an algal strain, documents that nZVI also caused oxidative damage to proteins in addition to lipids. The most sensitive toward nZVI exposure in terms of aldehyde production was the yeast strain Saccharomyces cerevisiae, which had an EC₅₀ value of 0.08 g/L nZVI. To the best of our knowledge, this paper is the first to document the production of aldehydes resulting from lipids and proteins as a result of OS in microorganisms from different kingdoms after exposure to iron nanoparticles.
显示更多 [+] 显示较少 [-]Cement dust induce stress and attenuates photosynthesis in Arachis hypogaea
2019
Shah, Kamran | Amin, Noor Ul | Ahmad, Imran | Ārā, Gulaśāna | Rahman, Mati Ur | Zuo, Xiya | Xing, Libo | Ren, Xiaolin
This study was conducted to investigate the changes in leaf physiological parameters to abiotic stress induced by different levels of cement dust. On day 15, Arachis hypogaea L. plants (sowing day was considered as day 0) were divided into six groups, and cement was sprinkled over plants with the help of hand pump, twice a week at T₁ (5 g pot⁻¹), T₂ (8 g pot⁻¹), T₃ (10 g pot⁻¹), T₄ (15 g pot⁻¹), T₅ (20 g pot⁻¹), and T₀/control (0 g pot⁻¹), until fruit maturity. Morphometric parameters such as root and shoot length, leaf area, and seed weight were significantly higher in T₀, while the minimum was recorded in T₅. Physiological analyses of leaves and roots revealed a remarkable reduction (p < 0.05) in sugar, amino acid, and protein contents, while the concentration of enzymatic antioxidants was increased in cement-treated plants. The concentration of abscisic acid in leaves was significantly higher in treatment groups as compared with control, while gibberellic acid concentration was low. Strikingly, cement dust decreases the level of leaf photosynthetic pigments, reduces stomatal conductance, and adversely affects photosynthesis. Leaf histological analysis revealed confirmatory evidence of stomatal closure, cell damage, reduced cell area, and abridged leaf thickness. Salient features of the present study provide useful evidence to estimate cement dust as a critical abiotic stress factor, which has adverse effects on photosynthesis, leaf anatomical features, stomatal functioning, and productivity. Our work opens new avenues for a deep portfolio of cement-based stress mediating pathophysiology in Arachis hypogaea.
显示更多 [+] 显示较少 [-]Resuspension of settled atmospheric particulate matter on plant leaves determined by wind and leaf surface characteristics
2019
Zheng, Guiling | Li, Peng
Atmospheric particulate matter (APM) is temporarily settled on the leaf surface of plants and will return to the air via the resuspension process under certain meteorological conditions. How leaf surface characteristics affect the resuspension of settled APM on the leaf surface has been rarely studied. Therefore, the resuspension of APM after settling on plant leaves was analyzed using four common urban greening species, including Prunus triloba, Platanus acerifolia, Lonicera maackii, and Cercis chinensis. The results show that the leaf hair density has a significantly positive correlation with the maximum particulate matter (PM) retention and natural PM retention (p < 0.05). Under the same wind speed, the proportions of the resuspended PM that settled on the leaf surfaces of the four plant species increase with the wind blowing time. During the same wind blowing time, the resuspension rate of the settled PM on leaf surfaces of P. triloba, P. acerifolia, and L. maackii increase with the wind speed. The leaf hair and stomatal density is negatively correlated to the resuspension rate of PM under the wind speed of 1 m s⁻¹ (p < 0.05), and the stomatal density is also negatively correlated to the resuspension rate of PM under the wind speed of 5 m s⁻¹ for 10 min or 20 min (p < 0.05). However, as the wind speed further increase, the leaf characteristics are no longer correlated to the resuspension rate of PM (p > 0.05). These results indicate that when the wind force (wind speed + wind blowing time) is small, the stomatal density and leaf hair density have a significant effect on APM resuspension. When the wind force is large, the influence of leaf surface structure on APM resuspension becomes less profound. APM resuspension is comprehensively affected by the external wind and the leaf surface characteristics, and these two factors jointly determine the fate of the PM after it settles on leaves.
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