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Anticoccidial and antioxidant effects of plants derived polyphenol in broilers exposed to induced coccidiosis Full text
2019
Alhotan, Rashed A. | Abudabos, Alaeldein
The comparative anticoccidial effects of herbal products with a standard synthetic anticoccidial drug on the production performance, intestinal histology, and some blood biochemical parameters in broilers exposed to experimental coccidiosis was investigated. One-day-old broiler chicks (n = 336) were randomly distributed into six groups. One group served as a control, the second was treated with the coccidial infection, the third was treated with synthetic anticoccidial drug (Elancoban), the fourth group was treated with an herbal product (Cozante), the fifth group of birds was treated with Norponin, and the sixth group was treated with Emanox. The results indicated that BWG, BW, FCR, and PEF decreased significantly (P < 0.05) in the positive control. Body weight gain, BW, and PEF were significantly (P < 0.01) high in Elancoban-treated birds. On day 25, lesion score was significantly (P < 0.01) low in duodenum, jejunum, and ceca in Elancoban-treated birds control. On day 30, lesion score was significantly (P < 0.05) low in Emanox-treated birds as compared with the positive control. Albumin concentration was significantly (P < 0.01) low in Emanox while glucose concentration was significantly (P < 0.01) high in all the treated groups compared with the positive control birds. The total antioxidant capacity was significantly (P < 0.05) high in Emanox on day 15 and 30 as compared with the positive control. The results showed that birds exposed to the natural anticoccidial products showed improved villi and total antioxidant capacity. We concluded that herbal products performed better than the positive control group.
Show more [+] Less [-]Synergistic effect of piperonyl butoxide and emamectin benzoate on enzymatic activities in resistant populations of red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) Full text
2019
Awan, Daud Ahmad | Ahmad, Faheem | Saleem, Mushtaq A. | Shakoori, Abdul Rauf
Resistance to grain protectants in Tribolium castaneum (Herbst) is a serious threat to international grain trade. Frequent and overdose application of chemical insecticides is becoming a serious health hazard and cause environmental pollution. Resistance management approaches by using various synergists along with novel compounds has become more imperative to increase efficacy of environmentally safe insecticides. We have evaluated piperonyl butoxide (PBO) and emamectin benzoate mixtures for management of resistant field populations of T. castaneum. The collected strains had demonstrated 50 to 200% resistance already developed against emamectin benzoate as compared with deltamethrin susceptible reference strain. The inclusion of PBO along with emamectin significantly reduced this resistance by at least 28% and the LC₅₀ were lowered from 5.12 to 1.9 μg/ml with the highest synergism ration of 2.7 in resistant strain. Enzymatic assays clearly demonstrated that the specific activities of catalase and acetylcholinesterases were significantly decreased at an average of 80% and 60%, respectively, when PBO was included as a synergist at 1:2 ratio with emamectin benzoate. The results highlight the mechanism that renders the field population resistant to emamectin benzoate and suggests the synergistic role of piperonyl butoxide as a potent additive in grain protectants for resistance management.
Show more [+] Less [-]Effect and mechanism of commonly used four nitrogen fertilizers and three organic fertilizers on Solanum nigrum L. hyperaccumulating Cd Full text
2019
Yang, Wei | Dai, Huiping | Dou, Xuekai | Zhang, Qianru | Wei, Shuhe
Solanum nigrum L. is a hyperaccumulator and shows very high phytoremediation potential for Cd-contaminated soil. Fertilizer addition to soil is an effective pathway to improve Cd hyperaccumulation. This article compared the strengthening roles of commonly used four nitrogen fertilizers with three organic fertilizers on S. nigrum hyperaccumulating Cd at the same total nitrogen level. The results showed that Cd concentrations in roots and shoots of S. nigrum were not affected by the addition of inorganic nitrogen like NH₄HCO₃, NH₄Cl, (NH₄)₂SO₄, and CH₄N₂O compared with the control without nitrogen addition. However, Cd concentrations in S. nigrum roots and shoots were significantly decreased (p < 0.05) when the organic nitrogen was added in the form of chicken manure, pig manure, and commercial organic fertilizer (by 15.6% and 15.1%, 30.1% and 23.6%, 20.3% and 16.8%, respectively). On the other hand, of all nitrogen treatments, the addition of (NH₄)₂SO₄ and CH₄N₂O to the soil enormously increased S. nigrum biomass, i.e., S. nigrum shoot biomass increased 2.0- and 2.1-fold compared with the control. Correspondingly, Cd loads in S. nigrum shoots were also the highest in former two treatments and amounted to 79.91 μg pot⁻¹ and 80.17 μg pot⁻¹, respectively. Compared with the control, the addition of three organic fertilizers significantly increased (p < 0.05) pH and decreased (p < 0.05) available Cd concentrations in the soil, which could be the main reasons for their negative effects on S. nigrum accumulating Cd. (NH₄)₂SO₄ and CH₄N₂O significantly increased S. nigrum biomasses and exerted no effects on the available soil Cd concentration, which made them more better fertilizers in practice. In general, the same fertilizer may show different effects on different hyperaccumulators. The selection of fertilizer should be decided in accordance with the specific conditions in the phytoremediation practice of contaminated soil.
Show more [+] Less [-]Reduction of FeII(EDTA)-NO by Mn powder in wet flue gas denitrification technology: stoichiometry, kinetics, and thermodynamics Full text
2019
Chen, Jun | He, Jinjia | Wang, Xiaoping | Hrynsphan, Dzmitry | Wu, Jiali | Chen, Jianmeng | Yao, Jiachao
Conversion of Feᴵᴵ(EDTA)-NO or Feᴵᴵᴵ(EDTA) into Feᴵᴵ(EDTA) is a key process in a wet flue gas denitrification technology with Feᴵᴵ(EDTA) solution. In this work, the stoichiometry, kinetics, and thermodynamics of Feᴵᴵ(EDTA)-NO reduction by Mn powder were investigated. We first studied the Feᴵᴵ(EDTA)-NO reduction and product distribution to speculate a possible stoichiometry of Feᴵᴵ(EDTA)-NO reduction by Mn powder. Then, the effects of major influencing factors, such as pH value, temperature, and Mn concentration, were studied. The pseudo-second-order model was established to describe the Feᴵᴵ(EDTA)-NO reduction. Simultaneously, according to Arrhenius and Eyring-Polanyi equations, the reaction activation energy (Eₐ), enthalpy of activation (∆H‡), and entropy of activation (∆S‡) were calculated as 23.68 kJ/mol, 21.148 kJ/mol, and − 149.728 J/(k mol), respectively. Additionally, simultaneous reduction of Feᴵᴵᴵ(EDTA) and Feᴵᴵ(EDTA)-NO was investigated to better study the mechanism of Feᴵᴵ(EDTA) regeneration, suggesting that there was a competition between the two reduction processes. Finally, a simple schematic mechanism of NO absorption by Feᴵᴵ(EDTA) combined with regeneration of manganese ion and ammonium was proposed. These fundamental researches could offer a valuable guidance for wet flue gas denitrification technology with Feᴵᴵ(EDTA) solution.
Show more [+] Less [-]Nitrogen and phosphorus removal from wastewater by sand with wheat straw Full text
2019
Le, Thi Huong Xuan | Mosley, Luke | Marschner, Petra
Nitrogen and phosphorus removal from wastewater by sand with wheat straw Full text
2019
Le, Thi Huong Xuan | Mosley, Luke | Marschner, Petra
Wheat straw amendment to sandy soil has the potential to remove nutrients from wastewater. This study investigated the ability of wheat straw to remove inorganic nitrogen (N) and phosphorus (P) from wastewater when mixed into sand at different rates. Wastewater from a sewage treatment plant was added to sand alone and amended with different wheat straw rates 2.5, 5, 7.5, 10, and 12.5 g wheat straw kg⁻¹ so that the sand was covered with about 15 cm of wastewater. Leaching was carried out after 4, 8, and 16 days and inorganic N and P were analysed after leaching in both the leachate and sand, as well as N₂O and CO₂ release. In the amended sand, nitrate was about fourfold lower throughout the experiment compared to sand alone. Ammonium was twofold higher than sand alone at 12.5 g straw kg⁻¹ throughout the experiment and on day 16 also at ≥ 5 g straw kg⁻¹. Leachate inorganic N concentration was up to 70-fold higher in sand alone than in amended soils irrespective of straw rate. On day 16, P leaching was about threefold lower and P retention was 40% higher in all amended treatments than sand alone. The redox potential in sand alone was higher than with straw amendments. With straw amendment, the release of CO₂ per day was six times higher than with sand alone and increased with straw rates, but very little N₂O and CH₄ was released throughout the experiment. It can be concluded that amendment of sand with wheat straw can remove large proportions of inorganic N and P from wastewater, even at low straw rates. Likely mechanisms for retention are dissimilatory nitrate reduction and subsequent binding of ammonium to straw for N, and binding to the straw and microbial uptake for P.
Show more [+] Less [-]Nitrogen and phosphorus removal from wastewater by sand with wheat straw Full text
2019
Le, T.H.X. | Mosley, L. | Marschner, P.
Published online: 22 February 2019 | Wheat straw amendment to sandy soil has the potential to remove nutrients from wastewater. This study investigated the ability of wheat straw to remove inorganic nitrogen (N) and phosphorus (P) from wastewater when mixed into sand at different rates. Wastewater from a sewage treatment plant was added to sand alone and amended with different wheat straw rates 2.5, 5, 7.5, 10, and 12.5 g wheat straw kg-1 so that the sand was covered with about 15 cm of wastewater. Leaching was carried out after 4, 8, and 16 days and inorganic N and P were analysed after leaching in both the leachate and sand, as well as N2O and CO2 release. In the amended sand, nitrate was about fourfold lower throughout the experiment compared to sand alone. Ammonium was twofold higher than sand alone at 12.5 g straw kg-1 throughout the experiment and on day 16 also at ≥ 5 g straw kg-1. Leachate inorganic N concentration was up to 70-fold higher in sand alone than in amended soils irrespective of straw rate. On day 16, P leaching was about threefold lower and P retention was 40% higher in all amended treatments than sand alone. The redox potential in sand alone was higher than with straw amendments. With straw amendment, the release of CO2 per day was six times higher than with sand alone and increased with straw rates, but very little N2O and CH4 was released throughout the experiment. It can be concluded that amendment of sand with wheat straw can remove large proportions of inorganic N and P from wastewater, even at low straw rates. Likely mechanisms for retention are dissimilatory nitrate reduction and subsequent binding of ammonium to straw for N, and binding to the straw and microbial uptake for P. | Thi Huong Xuan Le, Luke Mosley, Petra Marschner
Show more [+] Less [-]Microbial degradation of organophosphorus pesticides: novel degraders, kinetics, functional genes, and genotoxicity assessment Full text
2019
Jiang, Bo | Zhang, Nana | Xing, Yi | Lian, Luning | Chen, Yating | Zhang, Dayi | Li, Guanghe | Sun, Guangdong | Song, Yizhi
Farmland soil sprayed with organophosphorus pesticides (OPs) annually was investigated for the identification and characterization of OP-degrading microorganisms. Six bacterial strains were identified, including Brevundimonas faecalis MA-B12 and Alcaligenes faecalis subsp. parafaecalis MA-B13 for methamidophos degradation, Citrobacter freundii TF-B21 and Ochrobactrum intermedium TF-B23 for trichlorfon degradation, Ochrobactrum intermedium DV-B31 for dichlorvos degradation, and Bacillus cereus for dimethoate degradation. The optimal biodegradation conditions for OPs were obtained at pH 7.0 and incubation temperature ranging from 28 to 37 °C. In an 8-day batch test, biodegradation of the four OPs all followed first-order kinetics, with biodegradation rates ranging from 58.08 to 96.42%. Functional genes responsible for OPs degradation were obtained, including ophB, ampA, opdE, opd, opdA, and mpd. As these strains were indigenous strains isolated from farmland soils, they can be potentially used as bacterial consortium for the bioremediation of mixed OP-contaminated soils. A time-course genotoxicity assessment of the degradation products was done by a bacterial whole-cell bioreporter, revealing that biodegradation of trichlorfon, dichlorvos, and dimethoate resulted a decreased genotoxicity within 5 days, which, however, significantly increased on day 8. The result demonstrated that more toxic products may be produced during the biodegradation processes of OPs, and more attention should be put not only on the pesticides themselves, but also on the toxic effects of their degradation products. To the best of our knowledge, this is for the first time that the genotoxicity of OP degradation products was evaluated by the bioreporter assay, broadening our understanding on the genotoxic risks of OPs during biodegradation process. Graphical Abstract
Show more [+] Less [-]The conditional relationship between renewable energy and environmental quality in sub-Saharan Africa Full text
2019
Asongu, Simplice A. | Iheonu, Chimere O. | Odo, Kingsley O.
This paper complements existing literature by assessing the conditional relationship between renewable energy and environmental quality in a sample of 40 African countries for the period 2002 to 2017. The empirical evidence is based on fixed effects regressions and quantile fixed effects regressions. The findings from both estimation techniques show that renewable energy consistently decreases carbon dioxide (CO₂) emissions. Moreover, the negative effect is a decreasing function of CO₂ emissions or the negative effect of renewable energy on CO₂ emissions decreases with increasing levels of CO₂ emissions. In other words, countries with higher levels of CO₂ emissions consistently experience a less negative effect compared with their counterparts with lower levels of CO₂ emissions. Policy implications are discussed.
Show more [+] Less [-]Environmentalism in the EU-28 context: the impact of governance quality on environmental energy efficiency Full text
2019
Apergis, Nicholas | Garćıa, Claudia
Environmental policies are a significant cornerstone of a developed economy, but the question that arises is whether such policies lead to a sustainable growth path. It is clear that the energy sector plays a pivotal role in environmental policies, and although the current literature has focused on examining the link between energy consumption and economic growth through an abundance of studies, it does not explicitly consider the role of institutional or governance quality variables in the process. Both globalization and democracy are important drivers of sustainability, while environmentalism is essential for the objective of gaining a “better world.” Governance quality is expected to be the key, not only for economic purposes but also for the efficiency of environmental policies. To that end, the analysis in this paper explores the link between governance quality and energy efficiency for the EU-28 countries, spanning the period 1995 to 2014. The findings document that there is a nexus between energy efficiency and income they move together: the most efficient countries are in the group with higher GDP per capita. Furthermore, the results show that governance quality is an important driver of energy efficiency and, hence, of environmental policies.
Show more [+] Less [-]Aberrant neurotransmissional mRNAs in cerebral ganglions of rotenone-exposed Lumbricus terrestris exhibiting motor dysfunction and altered cognitive behavior Full text
2019
Subaraja, Mamangam | Janardhanam Vanisree, Arambakkam
Rotenone (ROT) was shown to affect cerebral ganglions (CGs) of Lumbricus terrestris as a pioneering observation in our earlier investigation. Though ROT is a well-known neurotoxin causing neurodegeneration (ND), the precipitation of movement dysfunction remains largely unknown. We have designed the current study to analyze motor abnormalities in worms by exposing them to different concentrations (0.0–0.4 ppm) of ROT for 7 days. GABA, cholinergic receptor, serotonin transporter (SERT), acetylcholine esterase (AchE), and dopamine–β-hydroxylase that are well known for their involvement in neuromuscular junctions were investigated by qRT-PCR. Further, neuronal mitochondrial genes (cytochrome C oxidase-2, NADH deydrogenase-1, cytochrome-b) and actin-1 that are essential for regeneration and calreticulin (phagocytosis) were investigated. The levels of neurotransmitters, lipids, ATPase, neuronal behavior analyses, and fluorescence analysis (lipid droplets) were performed in CGs which showed significant variations at 0.3 ppm. Ultrastructural changes in lipid droplet and neuromelatonin were prominent in 0.3 ppm. Dose-dependent effect of ROT on behavior alteration and expression of m-RNAs studied suggested that at 0.3 ppm, it could deteriorate motor and cognitive functions. We predict that perhaps, by virtue of its effect on cerebral ganglionic genes and their neurotransmitting potential, ROT may cause morbidities that resemble features characteristic of hemiparkinsonic degeneration.
Show more [+] Less [-]Removal of fecal indicator bacteria and antibiotic resistant genes in constructed wetlands Full text
2019
Lamori, Jennifer G. | Xue, Jia | Rachmadi, Andri T. | Lopez, Gerardo U. | Kitajima, Masaaki | Gerba, Charles P. | Pepper, Ian L. | Brooks, John P. | Sherchan, Samendra
Wastewater discharge evidently increased bacterial diversity in the receiving waterbodies. The objective of this study was to evaluate the effectiveness of a constructed wetland in reducing fecal indicator bacteria (FIB) and antibiotic resistant genes (ARGs). We determined the prevalence and attenuation of fecal indicator bacteria including Escherichia coli and enterococci, along with ARGs, and human-associated Bacteroidales (HF183) markers by quantitative polymerase chain reaction (qPCR) method. Three types of water samples (inlet, intermediate, and outlet) from a constructed wetland were collected once a month from May to December in 2013. The overall reduction of E. coli was 50.0% based on culture method. According to the qPCR result, the overall removal rate of E. coli was only 6.7%. Enterococci were found in 62.5% of the wetland samples. HF183 genetic marker was detected in all final effluent samples with concentration ranging from 1.8 to 4.22 log₁₀ gene copies (GC)/100 ml. Of the ARGs tested, erythromycin resistance genes (ermF) were detected in 79.2% of the wetland samples. The class 1 integrase (intI1) was detected in all water samples with concentration ranging from 0.83 to 5.54 log₁₀ GC/100 ml. The overall removal rates of enterococci, HF183, intI1, and ermF were 84.0%, 66.6%, 67.2%, and 13.1%, respectively.
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