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Potential of Microalgae for Protein Production
Published in Sanjeet Mehariya, Shashi Kant Bhatia, Obulisamy Parthiba Karthikeyan, Algal Biorefineries and the Circular Bioeconomy, 2022
Elena M. Rojo, Alejandro Filipigh, David Moldes, Marisol Vega, Silvia Bolado
On the other hand, ammonium (NH4+) can be toxic at concentrations above 25μM by acidification of the medium (Yaakob et al., 2021). pH changes the NH4+/NH3 buffer system and induces free ammonium content in the culture, which is particularly toxic for the photosynthetic apparatus, affecting the accumulation of primary metabolites, such as chlorophylls and protein (Ma et al., 2020).
Exam Questions and Solutions
Published in Volodymyr Ivanov, Environmental Microbiology for Engineers, 2020
A wastewater stream has a flow rate of 4,000 m3 d−1 and an average ammonium concentration of 200 mg NH4+-N L−1. The ammonium can be removed from wastewater using sequential nitrification and denitrification. Write down the balanced equation for nitrification, i.e. oxidation of ammonium (NH4+) to nitrate (NO3−), and calculate the daily consumption of oxygen for complete oxidation of ammonium in the wastewater stream.Write down the balanced equation for denitrification with methanol (CH3OH) as the electron donor and calculate the daily consumption of methanol for complete removal of nitrate from the wastewater stream.Describe nitrifying microorganisms. Why they can be used for co-metabolism/co-oxidation of water pollutants?Describe denitrifying microorganisms and how they can be used for soil bioremediation.
Nitrogen
Published in Barbara A. Hauser, Practical Manual of Wastewater Chemistry, 2018
Ammonium ion is a potential nutrient to microorganism life; upon oxidation in the receiving stream, it stimulates the growth of bacteria and algae. Unionized ammonia (the gas) is toxic to many organisms; even tiny quantities can be detrimental to life in the stream.
The use of recovered struvite and ammonium nitrate in fertigation in a horticultural rotation: agronomic and microbiological assessment
Published in Environmental Technology, 2022
Mar Carreras-Sempere, Carmen Biel, Marc Viñas, Miriam Guivernau, Rafaela Caceres
The former (i.e. bacteria, archaea and fungi) are the primary components of the soil food web and play a key role in the functioning, balance and stability of the soil ecosystem [25,26]. Thus, soil microbial biomass, activity and diversity are indicators of potential soil fertility and ecosystem productivity [27]. One major process in nitrogen cycling driven by soil microorganisms is the nitrification, divided into two steps, the conversion of ammonium (NH4+) or ammonia (NH3) to nitrite (NO2−), which is called ‘ammonia-oxidation’, and the further transformation of NO2− into nitrate (NO3−), called ‘nitrite-oxidation’. Ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB) and Nitrite-oxidizing bacteria (NOB) drive soil nitrification and appear to be sufficient physiological diverse within each group for growth in most terrestrial ecosystems [28] and other nature-based processes of organic matter transformation as composting [29]. Then, most of the horticultural crops take up N in the form of NH4+ or NO3− [30]. NH4+ uptake and assimilation are less energy demanding, indicating a competitive advantage for plants that possess a higher ammonium absorption capacity. However, high ammonium concentrations can cause severe toxicity symptoms [31]. Therefore, the dynamic N cycle involves the synergistic interaction between plants and microbial communities in the soil.
Application of Victorian brown coal for removal of ammonium and organics from wastewater
Published in Environmental Technology, 2018
Mohammad Amin Nazari, Farzad Mohaddes, Biplob Kumar Pramanik, Maazuza Othman, Tim Muster, Muhammed A. Bhuiyan
The most common technologies for ammonium removal are biological, air-stripping, adsorption and ion-exchange processes. The main methods for removing ammonium from municipal wastewater comprise different biological (anaerobic–aerobic and nitrification–denitrification) techniques [4]. However, consistent performance of biological processes is an issue as they are very sensitive to temperature, dissolved oxygen concentration, pH and organics concentration. Due to generation of gaseous nitrogen through these methods, recovering ammonium from wastewater is impractical [5]. Granular activated carbon adsorption is widely used in drinking water treatment for removal of nutrients and organics. Among all the practiced methods, ion-exchange seems attractive due to low cost and less energy requirement, short contact time, little influence at low temperature, ease of operation and environmental friendliness. Utilization of exhausted ion-exchanger as a fertilizer is another advantage associated with this technique [2,5].
Performance of concrete with blended binders in ammonium-sulphate solution
Published in Journal of Sustainable Cement-Based Materials, 2018
Ammonium-based salts are widely used as fertilizers in agricultural zones. Numerous reports [1,2] indicate that concrete in agricultural regions and factories that produce ammonium-based fertilizers such as ammonium sulfate and nitrate are vulnerable to severe chemical attack. Since a large volume of ammonium-based salts are often left in soil after industrial applications, concrete components in mining, nuclear and chemical industries using these salts may as well be exposed to external chemical attack. The magnitude and underlying mechanisms of damage induced by these salts may be different based on the associated anions. Ammonium sulfate attack on concrete is classified as the most aggressive type of sulfate attack characterized by an acid–sulfate damage resulting in softening, expansion, cracking, and spalling [1,3]. The combined effect of sulfate and ammonium ions on concrete is so severe that even when there is an array of different corrosive agents (Na2SO4, (NH4)2SO4, MgSO4, NaCl, KH2PO4) acting together, (NH4)2SO4 predominates the effect of other chemicals [4].