Ecosystem Protection through Myco-Remediation of Chromium and Arsenic

Area of Science:

• Environmental Microbiology
• Bioremediation
• Mycology

Background:

• Heavy metal pollution from chromium and arsenic poses a significant global environmental threat.
• Bioremediation using microorganisms offers a sustainable solution for contaminated sites.
• Fungal species demonstrate potential in sequestering and removing toxic heavy metals from soil.

Purpose of the Study:

• To isolate and identify fungal species capable of tolerating and removing chromium (Cr) and arsenic (As).
• To optimize culture conditions for enhanced heavy metal removal by selected fungal isolates.
• To evaluate the efficiency of identified fungal strains in the bioremediation of Cr- and As-contaminated soils.

Main Methods:

• Fungal isolates were obtained from contaminated soil samples using enrichment culture techniques on potato dextrose agar (PDA) media with Cr and As.
• Isolates were screened for minimum inhibitory concentrations (MIC) to assess heavy metal tolerance.
• Optimized culture conditions were used to determine the removal efficiency of selected isolates for Cr and As.

Main Results:

• Nineteen fungal isolates were obtained, with four isolates (C1, C3, A2, A6) exhibiting high tolerance (MIC >5000 mg/L).
• Isolates C1 and C3 achieved 58.60% and 57.00% chromium removal, respectively, at 50 mg/L.
• Isolates A6 and A2 achieved 80% and 56% arsenic removal, respectively, at 10 mg/L.
• Molecular identification revealed C1 as *Aspergillus tamarii* and A6 as *Aspergillus ustus*.

Conclusions:

• Fungal isolates, particularly *Aspergillus tamarii* and *Aspergillus ustus*, are effective agents for the bioremediation of chromium and arsenic-contaminated environments.
• Optimized conditions significantly enhance the heavy metal removal capabilities of these fungal strains.
• This study provides a foundation for developing fungal-based strategies to mitigate heavy metal pollution in soils.