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Aquatic Plants Native to Europe
Published in Namrita Lall, Aquatic Plants, 2020
Isa A. Lambrechts, Lydia Gibango, Antonios Chrysargyris, Nikolaos Tzortzakis, Namrita Lall
Although several phenolics, terpenes, and other phytochemicals have been isolated from the plant, no literature on its pharmacological use has been explored. At least 18 different phenolic compounds have been reported in M. spicatum with ellagic acid, gallic acid, and several tannic acids being the more abundant compounds compared to the other compounds (Figure 5.16). In very small concentrations, these compounds, namely ellagic acid, gallic acid, digallic acid, and tannic acids, inhibit the nitrification processes by Nitrosomonas sp. and Nitrobacter sp. (Planas et al. 1981).
Chemical Factors
Published in Michael J. Kennish, Ecology of Estuaries Physical and Chemical Aspects, 2019
Ammonium (NH+4) is the predominant inorganic nitrogen species in estuarine sediments, being stable under anaerobic conditions. Denitrification occurs within anaerobic sediments near the redox discontinuity layer, whereas nitrification takes place in the aerobic surface layer and the oxygenated water column. As nitrification proceeds in the upper, oxidized sediments, nitrate is produced and diffuses across the redox discontinuity layer into the anaerobic zone. Denitrifying bacteria utilize the nitrate within this zone. Hence, intense microbial action at the redox discontinuity layer facilitates the downward movement of nitrate into the anaerobic zone, where denitrification occurs, and the upward diffusion of ammonium into the aerobic zone, where nitrification takes place.192 An important process affecting dissolved ammonium distribution in sediments is reversible adsorption on sedimentary particles.193
3-Nitropropionate
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
Since the first isolation of 3-NPA almost a century ago, a wealth of knowledge has been gathered on its occurrence, metabolism, physiological roles, and toxicity. 3-NPA and its diverse ester derivatives have been found in fungi, plants, and insects. Under physiological conditions 3-NPA is in equilibrium with its conjugate base P3N, which is an irreversible inhibitor of succinate dehydrogenase. 3-NPA is currently proposed to be utilized by plants, fungi, and insects for self-protection or colonization of biological niches. The toxin and its derivatives may participate in the nitrification process as well. Poisoning of domestic livestock by 3-NPA has been documented and is majorly due to grazing on pastures with plants containing 3-NPA. Human exposure to 3-NPA through the consumption of moldy food has been reported, resulting in several deaths. Studies on the pathology and pathogenesis of 3-NPA have been intensively carried out because 3-NPA induces a series of symptoms that mimic those of Huntington disease. Mechanisms underlying the pathogenesis of 3-NPA involve three intertwined modalities pertaining to impairment of energy metabolism, oxidative stress, and excitotoxicity. Several enzymatic mechanisms have been characterized in fungi and bacteria for the detoxification of 3-NPA and its conjugate base P3N.
Multi-parametric groundwater quality and human health risk assessment vis-à-vis hydrogeochemical process in an Agri-intensive region of Indus basin, Punjab, India
Published in Toxin Reviews, 2022
Vijay Jaswal, Ravishankar Kumar, Prafulla Kumar Sahoo, Sunil Mittal, Ajay Kumar, Sunil Kumar Sahoo, Yogalakshmi Kadapakkam Nandabalan
(NO3−) in groundwater was observed high in the south-east part of the study area, unlike (SO42−) that showed elevated level in the central part of the study area. Around 20% of groundwater samples of the study area exceeded the recommended limit of 45 mgL−1 for NO3−. This region of Punjab that is well known for intensive agriculture practices and plantation of wheat and cotton as major crops might be the possible reason for increased NO3− in groundwater. According to Huang (2013), wheat requires high N− based fertilizers. According to ENVIS Centre of Punjab (2018), about 99,000 Tonnes of NPK (68,000 Tonnes of N, 28,000 Tonnes of P2O5 and 3,000 Tonnes of K2O) fertilizers were used during the year 2017. Leaching of nitrate released from the oxidation of organic matter, ammonification and nitrification of nitrogen-containing animal and human excreta might also be the reason for the elevated levels of nitrate in groundwater (Shukla and Saxena 2020a, 2020c, CGWB and GYBI 2012). Moreover, sandy soil in the study area's southern region might facilitate rapid infiltration and minimal evapotranspiration (Nakhaei et al. 2015). According to Ahada and Suthar (2018), elevated levels of SO4 in groundwater samples could be due to both natural (dissolution of sulfate and oxidation of sulfide containing minerals) and anthropogenic sources (power plants, phosphate processing refineries, metallurgical processes, etc.).
Graphene oxide influence in soil bacteria is dose dependent and changes at osmotic stress: growth variation, oxidative damage, antioxidant response, and plant growth promotion traits of a Rhizobium strain
Published in Nanotoxicology, 2022
Tiago Lopes, Paulo Cardoso, Diana Matos, Ricardo Rocha, Adília Pires, Paula Marques, Etelvina Figueira
Soil microorganisms, although constituting less than 0.5% (w/w) of soil mass, are an essential part of soil ecosystems, for playing important ecological roles that influence soil properties (Yan et al. 2015; Jansson and Hofmockel 2020). Oxidation, nitrification, ammonification, nitrogen fixation, and organic matter mineralization are processes driven by soil microorganisms that make nutrients available for plant uptake (Yan et al. 2015). Some climatic events can interfere with these processes, shifting microbial communities and affecting soil properties and soil nutrient cycles (Jansson and Hofmockel 2020). With the increase of extreme weather events, already taking place in Europe and predicted to increase along the twenty-first century (IPCC 2021), such as the prevalence of long and severe drought events, mainly in spring and summer), effects on microbial communities and the services they provide can be difficult to predict, especially in the Mediterranean region considered as a hotspot (IPCC 2021).
Hybrid powdered activated carbon-activated sludge biofilm formation to mitigate biofouling in dynamic membrane bioreactor for wastewater treatment
Published in Biofouling, 2022
Mohammad Reza Mehrnia, Fatemeh Nasiri, Fatemeh Pourasgharian Roudsari, Fatemeh Bahrami
According to Figure 5c, the hybrid PAC-DMBR was also able to remove TN. Generally, most of the soluble ammonium nitrogen (2011). Furthermore, an increase in the size of suspended flocs in presence of PAC particles according to particle size analysis can be an indication of biofilm formation around PAC particles. Such biofilms, including an inner anoxic layer and an outer aerobic layer, can facilitate nitrification and denitrification reactions (Qureshi et al. 2005). Although an in-depth investigation regarding biofilm structure around PAC in DMBR needs to be conducted in further studies, the results of the present study show the ability of hybrid PAC-DMBR in removing TN.