Dietary supplements and pro-opiomelanocortin in Siniperca chuatsi

Peer Reviewe

Biochar Extracts Can Modulate the Toxicity of Persistent Free Radicals in the Nematode Caenorhabditis elegans

As an effective soil amendment, biochars require a comprehensive ecological evaluation before they can be widely used in agriculture because endogenous contaminants, such as environmentally persistent free radicals (EPFRs), certainly pose an ecological risk to soil invertebrates. In this study, Caenorhabditis elegans (C. elegans) was used as a model organism to investigate the neurotoxicity of two rice straw biochars pyrolyzed at 500 and 700 °C. After 24 h exposure to unwashed biochar, washed biochar, and leaching fluids (supernatants), the neurobehavioral parameters of C. elegans were determined in a liquid toxicity test. The results showed that the washed 700 °C biochar particles significantly impaired locomotion and prolonged the defecation interval at a biochar concentration of 4 g·well−1, while the unwashed biochar and supernatants caused no apparent impairment. Supporting this, electron paramagnetic resonance (EPR) results showed that the intensity of EPFRs in unwashed 700 °C biochar was stronger than that of the corresponding washed particles. This indicates that, in the liquid test, the EPR signal alone is not indicative of particle toxicity. The accessibility and activity of the EPFRs should be considered. Dissolved organic matter (DOM) was observed in the leaching fluids. The neurotoxic activity of the washed biochar was alleviated after the re-addition of leaching fluids to the washed biochar, suggesting that the dissolved organic materials modulate the reactivity of the EPFRs in the liquid phase. This study suggests that the leaching process may increase the risk of biochar when used in the field environment.National Natural Scientific Foundation of ChinaYunnan Province Basic Research ProjectNSFC-NCNPeer Reviewe

Phenol-rich fulvic acid as a water additive enhances growth, reduces stress, and stimulates the immune system of fish in aquaculture

Aquaculture has become imperative to cover the demands for dietary animal protein. Simultaneously, it has to overcome prejudices from excessive use of antibiotics and environmental impacts. Natural supplements are traditionally applied orally. In this study, we demonstrated another pathway: the gills. Humic substances are immunostimulants and a natural part of every aquatic ecosystem, making them ideal to be used as bath stimulants. Five and 50 mg C/L of a fulvic acid-rich humic substance was added for 28 days to the water of juvenile rainbow trout (Oncorhynchus mykiss). This fulvic acid is characterized by a high content of phenolic moieties with persistent free radicals and a high electron exchange capacity. The high concentration of the fulvic acid significantly increased growth and reduced the food conversion ratio and the response to a handling-stressor. Phagocytosis and potential killing activity of head kidney leukocytes were increased, as well as the total oxyradical scavenging capacity (TOSC) and lysozyme activity in the gills. In conclusion, immunostimulation via gills is possible with our fulvic acid, and the high phenolic content improved overall health and stress resistance of fish.Bundesministerium für Wirtschaft und Energie http://dx.doi.org/10.13039/501100006360Projekt DEALPeer Reviewe

The Sorption of Sulfamethoxazole by Aliphatic and Aromatic Carbons from Lignocellulose Pyrolysis

Massive biomass waste with lignocellulose components can be used to produce biochar for environmental remediation. However, the impact of lignocellulose pyrolysis on biochar structure in relation to the sorption mechanism of ionizable antibiotics is still poorly understood. In this paper, diverse techniques including thermogravimetric analysis and 13C nuclear magnetic resonance were applied to investigate the properties of biochars as affected by the pyrolysis of cellulose and lignin in feedstock. Cellulose-derived biochars possessed more abundant groups than lignin-derived biochars, suggesting the greater preservation of group for cellulose during the carbonization. Higher sorption of sulfamethoxazole (SMX) was also observed by cellulose-derived biochars owing to hydrogen bond interaction. Sorption affinity gradually declined with the conversion aliphatic to aromatic carbon, whereas the enhanced specific surface area (SSA) subsequently promoted SMX sorption as evidenced by increased SSA-N2 and SSA-CO2 from 350 to 450 °C. The decreased Kd/SSA-N2 values with increasing pH values implied a distinct reduction in sorption per unit area, which could be attributed to enhanced electrostatic repulsion. This work elucidated the role of carbon phases from thermal conversion of lignocellulose on the sorption performance for sulfonamide antibiotics, which will be helpful to the structural design of carbonaceous adsorbents for the removal of ionizable antibiotics

How did the nutrient concentrations change in northeastern German lowland rivers during the last four millennia?

This study focuses on the feasibility of floodplain sediments and fluvial sediments in paleomeanders and ox-bows of two lowland rivers (River Havel, River Spree, Brandenburg State, Germany) as archives for quantitative paleolimnological reconstructions and potential basis of future river management strategies. The results presented provide a mean to differentiate between the natural and cultural eutrophication of rivers. Available transfer functions of littoral diatom assemblages in 84 Brandenburg lakes and river sites, and total phosphorus (TP) and total inorganic nitrogen (TN) were used to infer nutrient changes in the Rivers Havel and Spree since the last 4,000 years. In the River Spree near Platkow, fossil diatoms indicated moderate eutrophic TP- and TN-concentrations between 1300 and 1850 AD (TP: 36 µg dm-3, TN: 1,000 µg dm-3). During this time period, the human impact on the nutrient status of the River Spree was more or less indirect via increases of runoff from the catchment as a result of deforestation. In the second lowland river, the lower River Havel, diatom inferred TP-concentrations were 80 µg dm-3 in the late Subboreal (2,000 to 500 BC). That means that the natural diatom flora of this river was eutrophic; mesotrophic conditions even in times without intensive land use did not occur. Furthermore, the fossil diatom flora revealed a potential nitrogen limitation during summer times (till 1400 AD: TN 1,600 to 1,700 µg dm-3). Anthropogenic eutrophication impact on the River Havel can be detected since approximately 800 year ago. The diatom-inferred nitrogen/phosphorus-relation highlighted different trends in eutrophication history within the study area. Without human activities the ratio of both nutrient components was relatively constant. Anthropogenic changes in the catchment area led to a declining TN/TP ratio in the last 1,000 years with changes in algal communities, such as increases of nuisance cyanobacteria blooms in the last decades.Peer Reviewe

Eutrophication problems and their potential solutions in the artificial shallow lake Altmühlsee (Germany)

Lake Altmühlsee in Middle Franconia, Germany, was constructed as part of a water transportation system and flooded in 1986 by River Altmühl. Supply of nutrient rich water resulted in a hypertrophic state characterized by low Secchi depth (Peer Reviewe

Overlooked Risks of Biochars: Persistent Free Radicals trigger Neurotoxicity in <i>Caenorhabditis elegans</i>

In recent years, biochars have gained increasing interest in mitigating climate changes and revitalizing contaminated or drained soil. Studies determining their impact on the ecosystem, especially on soil invertebrates, however, are still scarce and the neurotoxic potential of biochars has never been evaluated before. Using the model organism <i>Caenorhabditis elegans</i> we determined the neurotoxic effect of biochar produced from rice straw by pyrolysis at 500 °C at concentrations ranging from 0 to 2000 mg C·L^–1. Biochar had a hormetic effect on locomotion behavior. Furthermore, high concentrations impaired defecation as well as the recognition and response to a chemical attractant. None of the potential toxic chemicals in the biochar had sufficient high concentrations to explain the detected neurotoxic effect. Using electron paramagnetic resonance (EPR) spectroscopy, we detected free radicals in the biochar. Detrimental reaction of free radicals with biotic macromolecules can induce oxidative stress responses and are a potential reason for the evaluated neurotoxic effect of biochar. Overall, we were able to prove that biochars have the potential to act as weak neurotoxins to soil organisms and effects of persistent free radicals should be investigated further

The Effect of Weather and Technology on Corn Yields in the Corn Belt, 1929-62

Excerpts from the report Summary: Recent increases in agricultural output have prompted agricultural researchers to investigate the roles of weather and technology in crop yields. This study assesses the relative effect of each on corn yields in the Corn Belt between 1929 and 1962. Weather indexes were constructed for all States of the Corn Belt and the Corn Belt as a whole. These measures were constructed from corn variety test data, and were used to adjust yield and output series for the influence of weather by a simple deflation process. State indexes were developed by aggregating weather indexes for individual locations. When the weather index is used to deflate the effect of weather on yields, the actual yield series may be adjusted to show the technological yield trend without the effects of weather. Variation in the adjusted yield series is an estimate of the effect of changes in technology. The weather index was also used to facilitate the analysis of the distribution of weather effects and the effect that improved technology has had in reducing fluctuations due to weather

Environmental signals: synthetic humic substances act as xeno-estrogen and affect the thyroid system of Xenopus laevis.

According to outdated paradigms humic substances (HS) are considered to be refractory or inert that do not directly interact with aquatic organisms. However, they are taken up and induce biotransformation activities and may act as hormone-like substances. In the present study, we tested whether HS can interfere with endocrine regulation in the amphibian Xenopus laevis. In order to exclude contamination with phyto-hormones, which may occur in environmental isolates, the artificial HS1500 was applied. The in vivo results showed that HS1500 causes significant estrogenic effects on X. laevis during its larval development and results of semi-quantitative RT-PCR revealed a marked increase of the estrogenic biomarker estrogen receptor mRNA (ER-mRNA). Furthermore, preliminary RT-PCR results showed that the thyroid-stimulating hormone (TSHbeta-mRNA) is enhanced after exposure to HS1500, indicating a weak adverse effect on T3/T4 availability. Hence, HS may have estrogenic and anti-thyroidal effects on aquatic animals, and therefore may influence the structure of aquatic communities and they may be considered environmental signaling chemicals.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe