Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators
Filamentous fungi native to heavy metals (HMs) contaminated sites have great potential for bioremediation, yet are still often underexploited. This research aimed to assess the HMs resistance and Hg remediation capacity of fungi isolated from the rhizosphere of plants resident on highly Hg-contamina...
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| Format: | Article |
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MDPI AG
2021-05-01
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| Series: | Journal of Fungi |
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| Online Access: | https://www.mdpi.com/2309-608X/7/5/386 |
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| author | Cristina L. Văcar Enikö Covaci Somsubhra Chakraborty Bin Li David C. Weindorf Tiberiu Frențiu Marcel Pârvu Dorina Podar |
| author_facet | Cristina L. Văcar Enikö Covaci Somsubhra Chakraborty Bin Li David C. Weindorf Tiberiu Frențiu Marcel Pârvu Dorina Podar |
| author_sort | Cristina L. Văcar |
| collection | DOAJ |
| description | Filamentous fungi native to heavy metals (HMs) contaminated sites have great potential for bioremediation, yet are still often underexploited. This research aimed to assess the HMs resistance and Hg remediation capacity of fungi isolated from the rhizosphere of plants resident on highly Hg-contaminated substrate. Analysis of Hg, Pb, Cu, Zn, and Cd concentrations by X-ray spectrometry generated the ecological risk of the rhizosphere soil. A total of 32 HM-resistant fungal isolates were molecularly identified. Their resistance spectrum for the investigated elements was characterized by tolerance indices (TIs) and minimum inhibitory concentrations (MICs). Clustering analysis of TIs was coupled with isolates’ phylogeny to evaluate HMs resistance patterns. The bioremediation potential of five isolates’ live biomasses, in 100 mg/L Hg<sup>2+</sup> aqueous solution over 48 h at 120 r/min, was quantified by atomic absorption spectrometry. New species or genera that were previously unrelated to Hg-contaminated substrates were identified. Ascomycota representatives were common, diverse, and exhibited varied HMs resistance spectra, especially towards the elements with ecological risk, in contrast to Mucoromycota-recovered isolates. HMs resistance patterns were similar within phylogenetically related clades, although isolate specific resistance occurred. <i>Cladosporium</i> sp., <i>Didymella glomerata</i>, <i>Fusarium oxysporum</i>, <i>Phoma costaricensis</i>, and <i>Sarocladium kiliense</i> isolates displayed very high MIC (mg/L) for Hg (140–200), in addition to Pb (1568), Cu (381), Zn (2092–2353), or Cd (337). The Hg biosorption capacity of these highly Hg-resistant species ranged from 33.8 to 54.9 mg/g dry weight, with a removal capacity from 47% to 97%. Thus, the fungi identified herein showed great potential as bioremediators for highly Hg-contaminated aqueous substrates. |
| first_indexed | 2024-03-10T11:24:17Z |
| format | Article |
| id | doaj.art-c6e82d87d19746e1a19e92e4202bc812 |
| institution | Directory Open Access Journal |
| issn | 2309-608X |
| language | English |
| last_indexed | 2024-03-10T11:24:17Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
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| series | Journal of Fungi |
| spelling | doaj.art-c6e82d87d19746e1a19e92e4202bc8122023-11-21T19:50:34ZengMDPI AGJournal of Fungi2309-608X2021-05-017538610.3390/jof7050386Heavy Metal-Resistant Filamentous Fungi as Potential Mercury BioremediatorsCristina L. Văcar0Enikö Covaci1Somsubhra Chakraborty2Bin Li3David C. Weindorf4Tiberiu Frențiu5Marcel Pârvu6Dorina Podar7Department of Molecular Biology and Biotechnology, Babeș-Bolyai University, 1 Kogălniceanu St., 400084 Cluj-Napoca, RomaniaDepartment of Analytical Chemistry, Babeș-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, RomaniaAgricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur 721302, IndiaDepartment of Experimental Statistics, Louisiana State University, Baton Rouge, LA 70803, USADepartment of Earth and Atmospheric Sciences, Central Michigan University, 1200 S. Franklin St., Mount Pleasant, MI 48859, USADepartment of Analytical Chemistry, Babeș-Bolyai University, 11 Arany Janos St., 400028 Cluj-Napoca, RomaniaCentre for Systems Biology, Biodiversity and Bioresources (3B), Babeș-Bolyai University, 3-5 Clinicilor St., 400015 Cluj-Napoca, RomaniaDepartment of Molecular Biology and Biotechnology, Babeș-Bolyai University, 1 Kogălniceanu St., 400084 Cluj-Napoca, RomaniaFilamentous fungi native to heavy metals (HMs) contaminated sites have great potential for bioremediation, yet are still often underexploited. This research aimed to assess the HMs resistance and Hg remediation capacity of fungi isolated from the rhizosphere of plants resident on highly Hg-contaminated substrate. Analysis of Hg, Pb, Cu, Zn, and Cd concentrations by X-ray spectrometry generated the ecological risk of the rhizosphere soil. A total of 32 HM-resistant fungal isolates were molecularly identified. Their resistance spectrum for the investigated elements was characterized by tolerance indices (TIs) and minimum inhibitory concentrations (MICs). Clustering analysis of TIs was coupled with isolates’ phylogeny to evaluate HMs resistance patterns. The bioremediation potential of five isolates’ live biomasses, in 100 mg/L Hg<sup>2+</sup> aqueous solution over 48 h at 120 r/min, was quantified by atomic absorption spectrometry. New species or genera that were previously unrelated to Hg-contaminated substrates were identified. Ascomycota representatives were common, diverse, and exhibited varied HMs resistance spectra, especially towards the elements with ecological risk, in contrast to Mucoromycota-recovered isolates. HMs resistance patterns were similar within phylogenetically related clades, although isolate specific resistance occurred. <i>Cladosporium</i> sp., <i>Didymella glomerata</i>, <i>Fusarium oxysporum</i>, <i>Phoma costaricensis</i>, and <i>Sarocladium kiliense</i> isolates displayed very high MIC (mg/L) for Hg (140–200), in addition to Pb (1568), Cu (381), Zn (2092–2353), or Cd (337). The Hg biosorption capacity of these highly Hg-resistant species ranged from 33.8 to 54.9 mg/g dry weight, with a removal capacity from 47% to 97%. Thus, the fungi identified herein showed great potential as bioremediators for highly Hg-contaminated aqueous substrates.https://www.mdpi.com/2309-608X/7/5/386mercurymycoremediationheavy metal resistance<i>Fusarium</i> sp.<i>Sarocladium</i> sp.biosorption |
| spellingShingle | Cristina L. Văcar Enikö Covaci Somsubhra Chakraborty Bin Li David C. Weindorf Tiberiu Frențiu Marcel Pârvu Dorina Podar Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators Journal of Fungi mercury mycoremediation heavy metal resistance <i>Fusarium</i> sp. <i>Sarocladium</i> sp. biosorption |
| title | Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators |
| title_full | Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators |
| title_fullStr | Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators |
| title_full_unstemmed | Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators |
| title_short | Heavy Metal-Resistant Filamentous Fungi as Potential Mercury Bioremediators |
| title_sort | heavy metal resistant filamentous fungi as potential mercury bioremediators |
| topic | mercury mycoremediation heavy metal resistance <i>Fusarium</i> sp. <i>Sarocladium</i> sp. biosorption |
| url | https://www.mdpi.com/2309-608X/7/5/386 |
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