Characterization of Aspergillus niger siderophore that mediates bioleaching of rare earth elements from phosphorites
- 31 Downloads
Siderophores are extra-cellular inducible compounds produced by aerobic microorganisms and plants to overcome iron insolubility via its chelation and then uptake inside the cell. This work aims to study the characteristics of siderophore that is produced by a rhizosphere-inhabiting fungus. This fungus has been morphologically and molecularly identified as Aspergillus niger with the ability to produce 87% siderophore units. The obtained siderophore in PDB medium gave a positive result with tetrazolium test and a characteristic spectrum with a maximum absorbance at 450 nm in FeCl3 test that did not shift in response to different pH degrees (5–9). This indicates that the obtained siderophore is a trihydroxymate in nature. After purification, the FTIR and NMR analyses showed that the obtained siderophore is considered to be ferrichrome. The purified siderophore has been further evaluated as a tool to extract uranium, thorium and rare earth elements (REEs) from Egyptian phosphorites obtained from Abu Tartur Mine area. The inductively coupled plasma atomic emission spectroscopy analysis showed that the highest removal efficiency percentage was for uranium (69.5%), followed by samarium (66.7%), thorium (55%), lanthanum (51%), and cerium (50.1%). This result confirmed the ability of hydroxymate siderophores to chelate the aforementioned precious elements, a result that paves the way for bioleaching to replace abiotic techniques in order to save the cost of such elements in an environmentally friendly way.
KeywordsAspergillus niger Bioleaching Egyptian phosphorites Ferrichrome Hydroxymate siderophores Rare earth elements
The authors thank Prof. Rania Zaky and Prof. Saad Shaaban, chemistry department, faculty of science, Mansoura University for interpretation of the FTIR and NMR data.
- Arnow LE (1937) Colorimetric determination of the components of 3, 4-dihydroxyphenylalanine-tyrosine mixtures. J Biol Chem 118:531–537Google Scholar
- Barnett HL, Hunter BB (1998) Illustrated genera of imperfect fungi, edn 4. American Phytopathological Society (APS Press), St. PaulGoogle Scholar
- Clark BL (2004) Characterization of a catechol-type siderophore and the detection of a possible outer membrane receptor protein from Rhizobium leguminosarum strain IARI 312. A M.Sc. thesis: presented to the faculty of the Department of Health Sciences East Tennessee State UniversityGoogle Scholar
- Gholami RM, Borghei S, Mousavi S (2011) Fungal leaching of hazardous heavy metals from a spent hydrotreating catalyst. World Acad Sci, Eng Technol, Int J Chem, Mol, Nucl, Mater Metall Eng 5:362–367Google Scholar
- Meyer Ja, Abdallah M (1978) The fluorescent pigment of Pseudomonas fluorescens: biosynthesis, purification and physicochemical properties. Microbiology 107:319–328Google Scholar
- Mirabello SA (2006) Influence of siderophore producing bacteria and organic ligands on phase distribution of cadmium and its uptake by Brassica napus in the presence of goethite. Cornell University, New YorkGoogle Scholar
- Patel D, Patel S, Thakar P, Saraf M (2017) Siderophore producing Aspergillus spp. as bioinoculant for enhanced growth of mung bean. Int J Adv Agric Sci Technol 6:111–120Google Scholar
- Wright WH IV (2010) Isolation and identification of the siderophore “vicibactin” produced by Rhizobium leguminosarum ATCC 14479. East Tennessee State University, Johnson CityGoogle Scholar
- Yeole R, Dave B, Dube H (2001) Siderophore production by fluorescent pseudomonads colonizing roots of certain crop plants.Google Scholar