title: Microfungal spores (Ustilago maydis and U. digitariae) immobilised chitosan microcapsules for heavy metal removal.
abstract: Designing effective chitosan-based biosorbents from unexploited biomass for heavy metal removal has received much attention over the past decade. Ustilago, loose smut, is a ubiquitous fungal plant pathogen infecting over 4000 species including maize and weed. This study aimed to establish whether the spores of the phytopathogenic microfungi Ustilago spores can be immobilised in cross-linked chitosan matrix, and it reports findings on heavy metal sorption performance of chitosan/Ustilago composite microcapsules. Immobilisation of Ustilago maydis and U. digitariae spores (from maize and weed) in chitosan microcapsules was achieved via glutaraldehyde cross-linking. The cross-linked microcapsules were characterised using scanning electron microscopy, FT-IR spectroscopy and thermogravimetric analysis. Sorption capacities of chitosan-U. maydis and chitosan-U. digitariae microcapsules were investigated and compared to cross-linked chitosan beads: Cu(II): 66.72, 69.26, 42.57; Cd(II): 49.46, 53.96, 7.87; Cr(III): 35.88, 49.40, 43.68; Ni(II): 41.67, 33.46, 16.43 and Zn(II): 30.73, 60.81, 15.04mg/g, respectively. Sorption experiments were conducted as a function of initial metal ion concentration (2-10mg/L), contact time (60-480min), temperature (25, 35 and 45°C), amount of the sorbent (0.05-0.25g) and pH of the metal solution. The microcapsules with spores exhibited better performance over the plain chitosan beads, demonstrating their potential use in water treatment.
authors.affiliation: Selcuk University, Faculty of Science, Department of Chemistry, 42075 Konya, Turkey. Electronic address: idrissargin@hotmail.com.
authors.forename: İdris
authors.initials: İ
authors.lastname: Sargın
authors.affiliation: Selcuk University, Faculty of Science, Department of Biochemistry, 42075 Konya, Turkey; Selcuk University, Advanced Research Technology and Application Center, 42075 Konya, Turkey.
authors.forename: Gulsin
authors.initials: G
authors.lastname: Arslan
authors.affiliation: Aksaray University, Faculty of Science and Letters, Department of Biotechnology and Molecular Biology, 68100 Aksaray, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Kaya
mesh_terms: D000327:Adsorption; D002214:Capsules / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D013172:Spores, Fungal / Q000737:chemistry*; D013696:Temperature; D013818:Thermogravimetry; D014588:Ustilago / Q000502:physiology*; D018508:Water Purification
chemical_list: D002214:Capsules; D019216:Metals, Heavy; D048271:Chitosan
keywords: Biopolymer; Fungal spores; Heavy metal; Microbead; Ustilago