Role of functional groups on Aspergillus niger biomass in the detoxification of hexavalent chromium.
Chromium (VI) contamination is not uncommon, especially near industries involved in leather tanning, chrome painting, metal cleaning and processing, wood preservation and alloy preparation. The mutagenic and carcinogenic properties of Chromium (VI) necessitate effective remedial processes. Difficulties associated with chemical and physical techniques to remediate a Chromium (VI) contaminated site to EPA recommended level (50 ppm), in addition to higher costs involved, assert the need for bioremedial measures. Biosorption can be one such solution to clean up heavy metal contamination. The objective of this study was to examine the main aspects of a possible strategy for the removal of Chromium (VI), employing Aspergillus niger biomass. The roles played by amines, carboxylic acids, phosphates, in Chromium (VI) biosorption were studied. Amino and the carboxy groups on the fungal cell wall play an important role in sorption. However, the role of carboxy group was far less than amino group. Surface adsorption of Chromium (VI) was also seen by scanning electron microscopy (SEM) thus indicating involvement of ion-exchange and surface adsorption mechanism in removal of Chromium (VI) ions.
Department of Microbiology, Institute of Science, 15, Madame Cama Road, Mumbai - 400 032. snehanarvekar@yahoo.com
Sneha
S
Narvekar
Varsha K
VK
Vaidya
D001234:Aspergillus niger / Q000378:metabolism*; D018533:Biomass; D002857:Chromium / Q000378:metabolism*; D052918:Environmental Restoration and Remediation; D008855:Microscopy, Electron, Scanning; D013055:Spectrophotometry, Infrared
D002857:Chromium