scholarly journals Utilization of the zebrafish model to unravel the harmful effects of biomass burning during Amazonian wildfires

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sanja Babić ◽  
Lara Čižmek ◽  
Aleksandra Maršavelski ◽  
Olga Malev ◽  
Maryline Pflieger ◽  
...  

AbstractAmazonian wildfires in 2019 have raised awareness about rainforest burning due to increased emissions of particulate matter and carbon. In the context of these emissions, by-products of lignin thermal degradation (i.e. methoxyphenols) are often neglected. Methoxyphenols entering the atmosphere may form intermediates with currently unknown reaction mechanisms and toxicity. This study for the first time provides a comprehensive insight into the impact of lignin degradation products [guaiacol, catechol], and their nitrated intermediates [4-nitrocatechol, 4,6-dinitroguaiacol, 5-nitroguaiacol] on zebrafish Danio rerio. Results revealed 4-nitrocatechol and catechol as the most toxic, followed by 4,6DNG > 5NG > GUA. The whole-organism bioassay integrated with molecular modeling emphasized the potential of methoxyphenols to inhibit tyrosinase, lipoxygenase, and carbonic anhydrase, consequently altering embryonic development (i.e. affected sensorial, skeletal, and physiological parameters, pigmentation formation failure, and non-hatching of larvae). The whole-organism bioassay integrated with in silico approach confirmed the harmful effects of lignin degradation products and their intermediates on aquatic organisms, emphasizing the need for their evaluation within ecotoxicity studies focused on aquatic compartments.

2011 ◽  
Vol 91 (4) ◽  
pp. 695-702 ◽  
Author(s):  
J. E. Ramirez-Bribiesca ◽  
Y. Wang ◽  
L. Jin ◽  
T. Canam ◽  
J. R. Town ◽  
...  

Ramirez-Bribiesca, J. E., Wang, Y., Jin, L., Canam, T., Town, J. R., Tsang, A., Dumonceaux, T. J. and McAllister, T. A. 2011. Chemical characterization and in vitro fermentation of Brassica straw treated with the aerobic fungus, Trametes versicolor . Can. J. Anim. Sci. 91: 695–702. Brassica napus straw (BNS) was either not treated or was treated with two strains of Trametes versicolor; 52J (wild type) or m4D (a cellobiose dehydrogenase-deficient mutant) with four treatments: (i) untreated control (C-BNS), (ii) 52J (B-52J), (iii) m4D (B-m4D) or (iv) m4D+glucose (B-m4Dg). Glucose was provided to encourage growth of the mutant strain. All treatments with T. versicolor decreased (P<0.05) neutral-detergent fibre and increased (P<0.05) protein and the concentration of lignin degradation products in straw. Ergosterol was highest (P<0.05) in straw treated with B-52J, suggesting it generated the most fungal biomass. Insoluble lignin was reduced (P<0.05) in straw treated with B-52J and B-m4D, but not with B-m4Dg. Mannose and xylose concentration were generally higher (P<0.05) in straw treated with fungi, whereas glucose and galactose were lower as compared with C-BNS. The four treatments above were subsequently assessed in rumen in vitro fermentations, along with BNS treated with 2 mL g−1of 5 N NaOH. Concentrations of total volatile fatty acids after 24 and 48h were lower (P<0.05) in incubations that contained BNS treated with T. versicolor as compared with C-BNSor NaOH-treated BNS. Compared with C-BNS, in vitrodry matter disappearance and gas production were increased (P<0.05) by NaOH, but not by treatment with either strain of T. versicolor. Although treatment with T. versicolor did release more lignin degradation products, it did not appear to provide more degradable carbohydrate to in vitro rumen microbial populations, even when a mutant strain with compromised carbohydrate metabolism was utilized. Production of secondary compounds by the aerobic fungi may inhibit rumen microbial fermentation.


2017 ◽  
Vol 5 (22) ◽  
pp. 11214-11223 ◽  
Author(s):  
Yuanzhe Song ◽  
Xuebing Zhao ◽  
Chao Wang ◽  
Han Bi ◽  
Jie Zhang ◽  
...  

Local heterogeneity in crystal lattice is directly observed in synthesized Li2MnO3/LiMO2 (M = Ni, Mn) cathode materials. With SAED application, for the first time, we accordingly uncover that the lattice heterogeneity is induced by different Li2MnO3 atomic arrangements coexisting in same crystal domain.


2007 ◽  
Vol 38 (4) ◽  
pp. 555-567 ◽  
Author(s):  
Karol Kuliński ◽  
Joanna Święta-Musznicka ◽  
Andrzej Staniszewski ◽  
Janusz Pempkowiak ◽  
Małgorzata Latałowa

1969 ◽  
Vol 47 (5) ◽  
pp. 723-727 ◽  
Author(s):  
J. M. Pepper ◽  
Y. W. Lee

A detailed comparative study has been made of the effectiveness of various catalysts for the hydrogenolysis of spruce wood lignin. The catalysts studied were Raney nickel, 10% palladium–charcoal, 5% rhodium–charcoal, 5% rhodium–alumina, 5% ruthenium–charcoal, and 5% ruthenium–alumina. Lignin degradation products were obtained initially as a chloroform-soluble fraction which was then divided and studied as diethyl ether-soluble and -insoluble fractions. Gas–liquid chromatographic separation of the ether-soluble fraction made possible the characterization and quantitative estimation of many of the lower molecular weight lignin degradation products.The data indicate that rhodium, palladium, and a limited amount of Raney nickel produce similar results as do ruthenium and an excess of Raney nickel; however, with the latter catalysts the degradation is more severe. In particular, rhodium–charcoal and palladium–charcoal appear to offer interesting advantages as catalysts for lignin hydrogenolysis.


BioResources ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. 4721-4732
Author(s):  
Shi Jia Dong ◽  
Bi Xian Zhang ◽  
Peng Zhang ◽  
Kun Yang Wu ◽  
Xin Miao He ◽  
...  

There is increasing interest in the application of ionic liquids for the pretreatment and fractionation of lignocelluloses. In this study, a series of functional acidic ionic liquids (ILs) with various heterocyclic organic cations were synthesized. Corn stalks were successfully fractionated into lignin, hemicelluloses, and cellulose when ultrasonically pretreated with ILs at 70 °C for 3 h, and subsequently treated with alkaline extraction. High yields of IL-isolated lignin (18.3% to 19.6%) and (8.3% to 14.6%) were obtained using ILs in the absence and presence of water, respectively. The yield of cellulose ranged from 40.0 to 77.0% from IL treatments, whereas the yield of hemicelluloses ranged from 1.1% to 17.3%. Enzymatic hydrolysis of the isolated cellulose residual produced 89.2% to 94.9% reducing sugar with 77.8% to 86.1% glucose, which corresponded to 80.5% to 91.4% enzymatic conversion of cellulose. Syringol and vanillin were found as the main lignin degradation products.


2014 ◽  
Vol 6 (2) ◽  
pp. 104-135 ◽  
Author(s):  
Panagiotis Andrikopoulos ◽  
Andreas Albin Hoefer ◽  
Vasileios Kallinterakis

Purpose – The purpose of this paper is to present and empirically test for the first time the hypothesis that herding in a market increases following the market's merger in an exchange group. Design/methodology/approach – The hypothesis is tested empirically in EURONEXT's four European equity markets (Belgium, France, the Netherlands and Portugal) on the premise of the Hwang and Salmon (2004) measure which allows us insight into the significance, structure and evolution of market herding. Tests are conducted for each market for the period prior to and after its merger into EURONEXT, controlling for a series of variables (market conditions, common risk factors, size) to gauge the robustness of the findings. Findings – Results indicate that, with the exception of Portugal, herding grows in significance, yet declines in momentum post-merger. The authors ascribe the findings to EURONEXT's enhanced transparency (which makes it easier for investors to observe their peers’ trades, thus allowing them to infer and free-ride on their information) and its fast-moving informational dynamics that render herding movements shorter-lived. These results are robust when controlling for various market states and common risk factors, with deviations being observed when controlling for size and market volatility. Originality/value – The study presents results for the first time on the impact of exchange mergers on herd behavior. The authors believe these to constitute useful stimulus for further research on the issue and bear important implications for regulators/policymakers in view of the ongoing proliferation of exchange mergers that has been underway since the 1990s.


2015 ◽  
Vol 282 (1806) ◽  
pp. 20150294 ◽  
Author(s):  
Deepa Senapathi ◽  
Luísa G. Carvalheiro ◽  
Jacobus C. Biesmeijer ◽  
Cassie-Ann Dodson ◽  
Rebecca L. Evans ◽  
...  

Change in land cover is thought to be one of the key drivers of pollinator declines, and yet there is a dearth of studies exploring the relationships between historical changes in land cover and shifts in pollinator communities. Here, we explore, for the first time, land cover changes in England over more than 80 years, and relate them to concurrent shifts in bee and wasp species richness and community composition. Using historical data from 14 sites across four counties, we quantify the key land cover changes within and around these sites and estimate the changes in richness and composition of pollinators. Land cover changes within sites, as well as changes within a 1 km radius outside the sites, have significant effects on richness and composition of bee and wasp species, with changes in edge habitats between major land classes also having a key influence. Our results highlight not just the land cover changes that may be detrimental to pollinator communities, but also provide an insight into how increases in habitat diversity may benefit species diversity, and could thus help inform policy and practice for future land management.


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