scholarly journals Magnetic Immobilization and Growth of Nannochloropsis oceanica and Scenedasmus almeriensis

Plants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 72
Author(s):  
Maria G. Savvidou ◽  
Angelo Ferraro ◽  
Petros Schinas ◽  
Diomi Mamma ◽  
Dimitris Kekos ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Organic Carbon ◽  
Cell Immobilization ◽  
Magnetic Surface ◽  
Nannochloropsis Oceanica ◽  
Preparation Methods ◽  
Protoplasts Regeneration ◽  
Protoplast Preparation ◽  
Surface Regeneration ◽  
Casamino Acids

Microalgae are used in industrial and pharmaceutical applications. Their performance on biological applications may be improved by their immobilization. This study presents a way of cell immobilization using microalgae carrying magnetic properties. Nannochloropsis oceanica and Scenedasmus almeriensis cells were treated enzymatically (cellulase) and mechanically (glass beads), generating protoplasts as a means of incorporation of magnetic nanoparticles. Scanning electron microscopy images verified the successful cell wall destruction for both of the examined microalgae cells. Subsequently, protoplasts were transformed with magnetic nanoparticles by a continuous electroporation method and then cultured on a magnetic surface. Regeneration of transformed protoplasts was optimized using various organic carbon and amino acid supplements. Both protoplast preparation methods demonstrated similar efficiency. Casamino acids, as source of amino acids, were the most efficient compound for N. oceanica protoplasts regeneration in enzymatic and mechanical treatment, while for S. almeriensis protoplasts regeneration, fructose, as source of organic carbon, was the most effective. Protoplasts transformation efficiency values with magnetic nanoparticles after enzymatic or mechanical treatments for N. oceanica and S. almeriensis were 17.8% and 10.7%, and 18.6% and 15.7%, respectively. Finally, selected magnetic cells were immobilized and grown on a vertical magnetic surface exposed to light and without any supplement.

scholarly journals Species level enrichment of AnAOB and associated growth morphology under the effect of key metabolites

2020 ◽  
Author(s):  
Yang Lu ◽  
Gayathri Natarajan ◽  
Thi Quynh Ngoc Nguyen ◽  
Sara Swa Thi ◽  
Krithika Arumugam ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Process Design ◽  
Control Strategies ◽  
Waste Water Treatment ◽  
Cell Immobilization ◽  
Ammonia Concentration ◽  
Species Level ◽  
Species Selection ◽  
Ammonium Oxidation ◽  
Nitrite Concentration

ABSTRACTNineteen anaerobic ammonium oxidizing bacteria (AnAOB) species have been identified, yet the environmental factors that select for each species within a specialized ecological niche have not been described. We enriched AnAOB from a single inoculum under standard enrichment conditions (reactor R1) with stepwise increase in nitrite and ammonia concentration, nitric oxide (NO) supplementation (reactor R2), or with complex organic carbon using wastewater collected from mainstream wastewater treatment facility (reactor R3). AnAOB were enriched up to 80%, 90% and 50% relative abundance in R1, R2 and R3 respectively. Candidatus Brocadia caroliniensis predominated in all reactors, but a shift towards Ca. Brocadia sinica was consistently observed with increasing ammonium and nitrite concentrations beyond 270 mg NH4-N L−1 and 340 mg NO2-N L−1, respectively. In the presence of NO, growth of heterotrophs were inhibited, and Ca. Jettenia could coexist with Ca. B. caroliniensis before diminishing when nitrite increased to 160 mg NO2-N L−1. In contrast, supplementation of organic carbon led to the emergence of heterotrophic communities that coevolved with Ca. B. caroliniensis. Ca. B. caroliniensis and Ca. Jettenia preferentially form biofilms on reactor surfaces, whereas Ca. Brocadia sinica forms granules in suspension. Our results thus indicate that multiple AnAOB species co-exist and occupy sub-niches in anaerobic ammonium oxidation reactors, that the dominant population can be reversibly shifted by, for example, changing the nitrogen load (i.e. high nitrite concentration favors Ca. Brocadia caroliniensis), and that speciation has implications for wastewater process design, with the optimum cell immobilization strategy (i.e. carriers vs granules) dependent on which species dominates.IMPORTANCEThis study demonstrates how to reversibly and predictably shift dominant anammox population using operating parameters (e.g. high nitrite concentration favours Ca. Brocadia sinica), and that species selection has implications for wastewater process design, illustrated here in terms of dependence of optimum cell immobilization strategy (i.e. carriers vs granules) on which species dominates. The research informs the characterization of AnAOBs at species level as well process design and control strategies targeting Anammox species population dynamics in full scale waste water treatment systems.

Functionalized magnetic nanosized materials for efficient biodiesel synthesis via acid–base/enzyme catalysis

2020 ◽  
Vol 22 (10) ◽  
pp. 2977-3012 ◽  
Author(s):  
Anping Wang ◽  
Putla Sudarsanam ◽  
Yufei Xu ◽  
Heng Zhang ◽  
Hu Li ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Critical Review ◽  
Enzyme Catalysis ◽  
Heterogeneous Catalysts ◽  
Acid Base ◽  
Preparation Methods ◽  
Performance Control ◽  
Nanosized Materials ◽  
Biodiesel Synthesis ◽  
And Performance

This critical review introduces the preparation methods, structural and performance control, protection, and functionalization of magnetic nanoparticles as easily recyclable and efficient heterogeneous catalysts for biodiesel synthesis.

scholarly journals Magnetic nanoparticles: preparation methods, applications in cancer diagnosis and cancer therapy

2016 ◽  
Vol 45 (1) ◽  
pp. 6-17 ◽  
Author(s):  
Saeid Shabestari Khiabani ◽  
Masoud Farshbaf ◽  
Abolfazl Akbarzadeh ◽  
Soodabeh Davaran
Keyword(s):  
Magnetic Nanoparticles ◽  
Cancer Therapy ◽  
Cancer Diagnosis ◽  
Preparation Methods

scholarly journals Review on functionalized magnetic nanoparticles for the pretreatment of organophosphorus pesticides

2021 ◽  
Vol 10 (1) ◽  
pp. 485-498
Author(s):  
Junpeng Tan ◽  
Ting Wang ◽  
Yong Li ◽  
Shenghui Xu ◽  
Simin Chen ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Nanoparticles ◽  
External Magnetic Field ◽  
Organophosphorus Pesticides ◽  
Complex Matrix ◽  
Preparation Methods ◽  
Simple Preparation ◽  
Functionalized Magnetic Nanoparticles ◽  
Short Time

Abstract Organophosphorus pesticides are currently extensively applied on the control of agricultural and forestry pests. The number of poisonings and deaths caused by organophosphorus pesticides are increasing year by year. Because of the complex matrix, numerous interfering substances, and low poison content, pretreatment methods are crucial for the detection and analysis of such cases. As an adsorbent used for pretreatment, magnetic nanoparticles have the advantages of simple preparation, convenient modification, superparamagnetism, and hydrophilicity. Microextraction can be performed with small amount of magnetic nanoparticles in a short time, and the target substances can be separated with an external magnetic field. In this paper, the latest research achievements are reviewed. Based on the introduced characteristics and preparation methods of magnetic nanoparticles, this paper outlines the applications of different functionalized magnetic nanoparticles for the pretreatment of organophosphorus pesticides and predict the potential research prospects.

scholarly journals Technical note: Uncovering the influence of methodological variations on the extractability of iron-bound organic carbon

2021 ◽  
Vol 18 (11) ◽  
pp. 3409-3419
Author(s):  
Ben J. Fisher ◽  
Johan C. Faust ◽  
Oliver W. Moore ◽  
Caroline L. Peacock ◽  
Christian März
Keyword(s):  
Organic Carbon ◽  
Marine Sediments ◽  
Freeze Drying ◽  
Method Comparison ◽  
Technical Note ◽  
Synthetic Sample ◽  
Fixed Amount ◽  
Preparation Methods ◽  
Reactive Iron ◽  
Cbd Method

Abstract. Association of organic carbon (OC) with reactive iron (FeR) represents an important mechanism by which OC is protected against remineralisation in soils and marine sediments. Recent studies indicate that the molecular structure of organic compounds and/or the identity of associated FeR phases exert a control on the ability of an OC–FeR complex to be extracted by the citrate–bicarbonate–dithionite (CBD) method. However, many variations of the CBD extraction are used, and these are often uncalibrated to each other, rendering comparisons of OC–FeR values extracted via the different methods impossible. Here, we created synthetic ferrihydrite samples coprecipitated with simple organic structures and subjected these to modifications of the most common CBD method. We altered some of the method parameters (reagent concentration, time of the extraction and sample preparation methods) and measured FeR recovery to determine which (if any) modifications affected the release of FeR from the synthetic sample. We provide an assessment of the reducing capacity of Na dithionite in the CBD method (the amount of Fe reduced by a fixed amount of dithionite) and find that the concentration of dithionite deployed can limit OC–FeR extractability for sediments with a high FeR content. Additionally, we show that extending the length of any CBD extraction offers no benefit in removing FeR. Moreover, we demonstrate that for synthetic OC–FeR samples dominated by ferrihydrite, freeze-drying samples can significantly reduce OC–FeR extractability; this appears to be less of an issue for natural marine sediments where natural ageing mechanisms may mimic the freeze-drying process for more stable Fe phases. While our study is not an all-inclusive method comparison and is not aimed at delivering the “perfect” extraction setup, our findings provide a collected summary of critical factors which influence the efficiency of the CBD extraction for OC–FeR. As such, we provide a platform from which OC–FeR values obtained under different methods can be interpreted and future studies of sediment carbon cycling can build upon.

Preparation Methods of Copper-Ferrocyanide Functionalized Magnetic Nanoparticles for Selective Removal of Cesium in Aqueous Solution

2013 ◽  
Author(s):  
Hee-Man Yang ◽  
Kune Woo Lee ◽  
Bum-Kyoung Seo ◽  
Jei Kwon Moon
Keyword(s):  
Aqueous Solution ◽  
Magnetic Nanoparticles ◽  
Magnetite Nanoparticles ◽  
Selective Removal ◽  
Radioactive Cesium ◽  
Preparation Methods ◽  
External Magnet ◽  
Copper Ferrocyanide ◽  
Functionalized Magnetic Nanoparticles

Copper ferrocyanide functionalized magnetite nanoparticles (Cu-FC-MNPs) were successfully synthesized by the immobilization of copper and ferrocyanide on the surface of [1-(2 amino-ethyl)-3-aminopropyl] trimethoxysilane modified magnetite nanoparticles. A radioactive cesium (Cs) adsorption test was carried out to investigate the effectiveness of Cu-FC-MNPS for the removal of radioactive Cs. Furthermore, the Cu-FC-MNPs showed excellent separation ability by an external magnet in an aqueous solution.

Magnetic hybrid materials in liquid crystals

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Martin Hähsler ◽  
Ingo Appel ◽  
Silke Behrens
Keyword(s):  
Liquid Crystals ◽  
Magnetic Nanoparticles ◽  
Hybrid Materials ◽  
Hybrid Material ◽  
Colloidal Stability ◽  
General Introduction ◽  
Preparation Methods ◽  
Semiconducting Properties ◽  
Dendritic Structures

AbstractThe integration of nanoparticles with magnetic, ferroelectric or semiconducting properties into liquid crystals (LCs) has attracted great interest both for fundamental investigations and for technological applications. Here, an overview of hybrid materials based on magnetic nanoparticles (MNPs) and thermotropic LCs is given. After a general introduction to thermotropic LCs and LC-MNP hybrid materials, various preparation methods established by us are presented. The synthesis of shape-(an)isotropic MNPs, their functionalization by tailored (pro)mesogenic ligands with linear or dendritic structures and their integration into LC hosts are discussed. The characterization of the MNPs, (pro)mesogenic ligands and resulting MNP-LC hybrid materials is described to show the influence of MNP functionalization on the MNP-LC interactions including aspects such as colloidal stability and structuring in the LC host. Overall, we show that the physical properties of the hybrid material are significantly influenced not only by the MNPs (i.e., their size, shape and composition) but also by their surface properties (i.e., the structure of the (pro)mesogenic ligands).

Removal of Total Organic Carbon from Sewage Wastewater Using Poly(ethylenimine)-Functionalized Magnetic Nanoparticles

Langmuir ◽  
2014 ◽  
Vol 30 (4) ◽  
pp. 1036-1044 ◽  
Author(s):  
Ramnath Lakshmanan ◽  
Margarita Sanchez-Dominguez ◽  
Jose A. Matutes-Aquino ◽  
Stefan Wennmalm ◽  
Gunaratna Kuttuva Rajarao
Keyword(s):  
Magnetic Nanoparticles ◽  
Organic Carbon ◽  
Total Organic Carbon ◽  
Functionalized Magnetic Nanoparticles

scholarly journals Technical Note: Uncovering the influence of methodological variations on the extractability of iron bound organic carbon

2020 ◽  
Author(s):  
Ben J. Fisher ◽  
Johan C. Faust ◽  
Oliver W. Moore ◽  
Caroline L. Peacock ◽  
Christian März
Keyword(s):  
Organic Carbon ◽  
Freeze Drying ◽  
Global Carbon Cycle ◽  
Technical Note ◽  
Preparation Methods ◽  
Reactive Iron ◽  
Concentration Time ◽  
Cbd Method ◽  
Global Carbon ◽  
Insight Into

Abstract. Association of organic carbon (OC) with reactive iron (FeR) represents an important mechanism by which OC is protected against remineralisation in soils and marine sediments. Recent studies indicate that the molecular structure of organic compounds and/or the identity of associated FeR phases exerts a control on the ability of an OC-FeR complex to be extracted by the citrate-bicarbonate-dithionite (CBD) method. While many variations of this method exist in the literature, these are often uncalibrated to each other, rendering comparisons of OC-FeR values extracted by different method iterations impossible. Here, we created a synthetic ferrihdyrite sample coprecipitated with simple organic structures and subjected these to modifications of the most common CBD method. Method parameters (reagent concentration, time of the extraction and sample preparation methods) were altered and FeR recovery measured to determine which (if any) modifications resulted in the greatest release of FeR from the sediment sample. We provide an assessment of the reducing capacity of Na dithionite in the CBD method and find that the concentration of dithionite deployed can limit OC-FeR extractability for sediments with a high FeR content. Additionally, we show that extending the length of any CBD extraction offers no benefit in removing FeR. Finally, we demonstrate that for synthetic OC-FeR samples, the almost universal technique of freeze drying samples can significantly reduce OC-FeR extractability and we offer insight into how this may translate to environmental samples using Arctic Ocean sediments. These results provide a valuable perspective on how the efficiency of this extraction could be improved to provide a more accurate assessment of sediment OC-FeR content. Accurate determinations of OC-FeR in sediments and soils represents an important step in improving our understanding of, and ability to model, the global carbon cycle.

Sign in / Sign up

Export Citation Format

Share Document