Biodegradable, metal-chelating compounds as alternatives to EDTA for cultivation of marine microalgae

AbstractIron (Fe) is an essential nutrient for microalgal metabolism. The low solubility of Fe in oxic aquatic environments can be a growth-limiting factor for phytoplankton. Synthetic chelating agents, such as ethylenediaminetetraacetic acid (EDTA), are used widely to maintain Fe in solution for microalgal cultivation. The non-biodegradable nature of EDTA, combined with sub-optimal bioavailability of Fe-EDTA complexes to microalgae, indicates opportunity to improve microalgal cultivation practices that amplify production efficiency and environmental compatibility. In the present study, the effects of four organic chelating ligands known to form readily bioavailable organic complexes with Fe in natural aquatic environments were investigated in relation to growth and biochemical composition of two marine microalgae grown as live feeds in shellfish hatcheries (Chaetoceros calcitrans and Tisochrysis lutea). Three saccharides, alginic acid (ALG), glucuronic acid (GLU), and dextran (DEX), as well as the siderophore desferrioxamine B (DFB), were compared to EDTA. Organic ligands characterized by weaker binding capacity for cationic metals (i.e., ALG, GLU, DEX) significantly improved microalgal growth and yields in laboratory-scale static batch cultures or bubbled photobioreactors. Maximal microalgal growth enhancement relative to the control (e.g., EDTA) was recorded for GLU, followed by ALG, with 20–35% increase in specific growth rate in the early stages of culture development of C. calcitrans and T. lutea. Substitution of EDTA with GLU resulted in a 27% increase in cellular omega 3-polyunsaturetd fatty acid content of C. calcitrans and doubled final cell yields. Enhanced microalgal culture performance is likely associated with increased intracellular Fe uptake efficiency combined with heterotrophic growth stimulated by the organic ligands. Based upon these results, we propose that replacement of EDTA with one of these organic metal-chelating ligands is an effective and easily implementable strategy to enhance the environmental compatibility of microalgal cultivation practices while also maximizing algal growth and enhancing the nutritional quality of marine microalgal species commonly cultured for live-feed applications in aquaculture.

Download Full-text

Metal scavenging and catalysis by periodic mesoporous organosilicas with 2,2′‐bipyridine metal chelating ligands

Applied Organometallic Chemistry ◽

10.1002/aoc.6341 ◽

2021 ◽

Author(s):

Minoru Waki ◽

Shinji Inagaki

Keyword(s):

Chelating Ligands ◽

Periodic Mesoporous Organosilicas ◽

Metal Chelating ◽

Mesoporous Organosilicas

Download Full-text

Regulation of magnetic relaxation behavior by replacing 3d transition metal ions in [M2Dy2] complexes containing two different organic chelating ligands

Dalton Transactions ◽

10.1039/c9dt00774a ◽

2019 ◽

Vol 48 (27) ◽

pp. 10011-10022 ◽

Cited By ~ 10

Author(s):

Hui-Sheng Wang ◽

Cheng-Ling Yin ◽

Zhao-Bo Hu ◽

Yong Chen ◽

Zhi-Quan Pan ◽

...

Keyword(s):

Transition Metal ◽

Metal Ions ◽

Single Molecule ◽

Magnetic Relaxation ◽

Transition Metal Ions ◽

Relaxation Behavior ◽

Organic Ligands ◽

Chelating Ligands ◽

Single Molecule Magnet

Two [MIII2DyIII2] complexes (M = Fe for 1 and Co for 2) with mixed organic ligands were obtained. Complex 2 exhibits single molecule magnet behavior with Ueff = 64.0(9) K.

Download Full-text

Diaquabis[N-(2-fluorobenzyl)-N-nitrosohydroxylaminato-κ2O,O′]nickel(II)

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536814002876 ◽

2014 ◽

Vol 70 (3) ◽

pp. m98-m99

Author(s):

Olga Kovalchukova ◽

Ali Sheikh Bostanabad ◽

Adam Stash ◽

Svetlana Strashnova ◽

Igor Zyuzin

Keyword(s):

Hydrogen Bonds ◽

Organic Ligands ◽

Water Molecules ◽

Chelating Ligands ◽

Two Dimensional ◽

Organic Species ◽

Octahedral Environment ◽

Dimensional Network ◽

Distorted Octahedral ◽

Coordinated Water

In the centrosymmetric title compound, [Ni(C7H6FN2O2)2(H2O)2], the NiIIcation is in a slightly distorted octahedral environment and is surrounded by four O atoms from the N—O groups of the organic ligands [Ni—O = 2.0179 (13) and 2.0283 (12) Å], and two water molecules [Ni—O = 2.0967 (14) Å]. TheN-(2-fluorobenzyl)-N-nitrosohydroxylaminate monoanions act as bidentate chelating ligands. In the crystal, the Ni cations in the columns are shifted in such a way that the coordinated water molecules are involved in the formation of hydrogen bonds with the O atoms of the organic species of neighbouring molecules. Thus, a two-dimensional network parallel to (100) is built up by hydrogen-bonded molecules.

Download Full-text

Dense Monolayers of Metal-Chelating Ligands Covalently Attached to Carbon Electrodes Electrochemically and Their Useful Application in Affinity Binding of Histidine-Tagged Proteins

Langmuir ◽

10.1021/la047139y ◽

2005 ◽

Vol 21 (8) ◽

pp. 3362-3375 ◽

Cited By ~ 75

Author(s):

Ronald Blankespoor ◽

Benoît Limoges ◽

Bernd Schöllhorn ◽

Jean-Laurent Syssa-Magalé ◽

Dounia Yazidi

Keyword(s):

Carbon Electrodes ◽

Affinity Binding ◽

Chelating Ligands ◽

Metal Chelating

Download Full-text

Harmful Impacts of Heavy Metals and Utility of Biosorption Technique for Their Removal from Wastewater: A Review

Journal of Chemistry Environmental Sciences and its Applications ◽

10.15415/jce.2021.81001 ◽

2022 ◽

Vol 8 (1) ◽

pp. 1-17

Author(s):

Ankita Negi ◽

Rajesh Kumar ◽

Sushil Kumar Joshi ◽

Arpita Negi ◽

Bhuvnesh Kumar ◽

...

Keyword(s):

Heavy Metals ◽

Metal Ion ◽

Membrane Filtration ◽

Literature Survey ◽

Ion Concentration ◽

Aquatic Environments ◽

Chelating Ligands ◽

Commercial Use ◽

Removal Of Heavy Metals ◽

Traditional Approaches

The increasing number of efluents discharged from the source of water (urban, industrial, agricultural etc.), is resulting in a higher concentration of heavy metals in the source. Heavy metals have a density of over 5g/cm3 to the metals. These are toxic, mutagenic, carcinogenic and resistant in watery and non-aquatic environments and impact water and non-water bodies seriously by substituting the basic metals of the same function. The extraction from the wastewater can be done in numerous techniques for example using an ion replacement, membrane filtration, osmosis, etc. This study discusses the adverse effects of heavy metals on the human body, the benefits of biosorption over traditional approaches for removal of heavy metals, the different biosorbents used to extract heavy metals and concerning issues regarding its commercial use, offering a wider viewpoint for the diversity of biosorbents and utilization of biosorption technique. It is evident from the profound literature survey that pH, biosorbent particle size, contact time, initial metal ion concentration, presence of chelating ligands etc. are some factors that affect the rate and extent of biosorption.

Download Full-text

Tin-Carbon Cleavage of Organotin Compounds by Pyoverdine from Pseudomonas chlororaphis

Applied and Environmental Microbiology ◽

10.1128/aem.69.2.878-883.2003 ◽

2003 ◽

Vol 69 (2) ◽

pp. 878-883 ◽

Cited By ~ 34

Author(s):

Hiroyuki Inoue ◽

Osamu Takimura ◽

Ken Kawaguchi ◽

Teruhiko Nitoda ◽

Hiroyuki Fuse ◽

...

Keyword(s):

Catalytic Properties ◽

Fluorescent Pseudomonads ◽

Organotin Compounds ◽

Pseudomonas Chlororaphis ◽

Chelating Ligands ◽

Metal Chelating ◽

Degrading Bacterium ◽

Acyl Substituent ◽

Degradation Activity ◽

Culture Supernatants

ABSTRACT The triphenyltin (TPT)-degrading bacterium Pseudomonas chlororaphis CNR15 produces extracellular yellow substances to degrade TPT. Three substances (F-I, F-IIa, and F-IIb) were purified, and their structural and catalytic properties were characterized. The primary structure of F-I was established using two-dimensional nuclear magnetic resonance techniques; the structure was identical to that of suc-pyoverdine from P. chlororaphis ATCC 9446, which is a peptide siderophore produced by fluorescent pseudomonads. Spectral and isoelectric-focusing analyses revealed that F-IIa and F-IIb were also pyoverdines, differing only in the acyl substituent attached to the chromophore part of F-I. Furthermore, we found that the fluorescent pseudomonads producing pyoverdines structurally different from F-I showed TPT degradation activity in the solid extracts of their culture supernatants. F-I and F-IIa degraded TPT to monophenyltin via diphenyltin (DPT) and degraded DPT and dibutyltin to monophenyltin and monobutyltin, respectively. The total amount of organotin metabolites produced by TPT degradation was nearly equivalent to that of the F-I added to the reaction mixture, whereas DPT degradation was not influenced by monophenyltin production. The TPT degradation activity of F-I was remarkably inhibited by the addition of metal ions chelated with pyoverdine. On the other hand, the activity of DPT was increased 13- and 8-fold by the addition of Cu2+ and Sn4+, respectively. These results suggest that metal-chelating ligands common to pyoverdines may play important roles in the Sn-C cleavage of organotin compounds in both the metal-free and metal-complexed states.

Download Full-text

Mixed chelating ligands used to regulate the luminescence of Ln(iii) complexes and single-ion magnet behavior in Dy-based analogues

Dalton Transactions ◽

10.1039/c8dt03133a ◽

2018 ◽

Vol 47 (44) ◽

pp. 15929-15940 ◽

Cited By ~ 24

Author(s):

Hai-Ling Wang ◽

Xiong-Feng Ma ◽

Hua-Hong Zou ◽

Kai Wang ◽

Bo Li ◽

...

Keyword(s):

Organic Ligands ◽

Chelating Ligands ◽

Solvothermal Conditions

The organic ligands 5,7-dibromo-2-methyl-8-quinolinol (L1), 1,10-phenanthroline (L2), and 5,7-dichloro-2-methyl-8-quinolinol (L3) were used to react with Dy(NO3)3·6H2O under solvothermal conditions at 80 °C to obtain the complexes [Dy(L1)3(H2O)] (1), [Dy(L2)2(NO3)3] (2), and [Dy(L3)3(H2O)] (3), respectively.

Download Full-text