Bioremediation of Hexavalent Chromium and Tannic Acid in Synthetic Tannery Wastewater Using Free and Calcium Alginate-Immobilized Spores and Mycelia of Aspergillus niger and Aspergillus parasiticus

• Published in: Bioremediation journal Vol. 14; no. 3; pp. 142 - 149
• Main Authors: Shugaba, A., Wuyep, P. A., Nok, A. J., Ameh, D. A., Lori, J. A.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 01-07-2010; Taylor & Francis; Taylor & Francis Ltd
• Subjects: Acids; Aspergillus niger; Aspergillus parasiticus; Aspergillus sp; Beads; Biodegradation of pollutants; Biological and medical sciences; Bioremediation; Biotechnology; Cell culture; Chromates; Chromium; Culture; Environment and pollution; Fundamental and applied biological sciences. Psychology; Fungi; immobilized spore/cell; Industrial applications and implications. Economical aspects; Nutrient removal; Spores; tannery effluent; Tannic acid; Waste water; Water treatment; Calcium; Immobilized cell; Alginates; Tannery; Spores; tannery effluent; Waste water; Fungi; Aspergillus parasiticus; Aspergillus niger; Fungi Imperfecti; Bioremediation; Aspergillus sp; Chromium VI; Effluent; immobilized spore/cell
• ISSN: 1088-9868; 1547-6529
• DOI: 10.1080/10889868.2010.495661

The bioremediation of chromate and tannic acid in synthetic tannery wastewater was studied in a batch culture system using free and immobilized spores and mycelia of A. niger and A. parasiticus. Significant (p< .001) decreases in total dissolved solids (TDS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), Cr(VI), and tannic acid concentrations were observed in cultures of both fungi after 96 h of growth. The A. niger culture medium had significantly lower TDS (p< .001), BOD, and tannic acid concentration (p< .05) compared to that of A. parasiticus. Immobilization of both spores and mycelia of the two fungi on Ca-alginate resulted in significantly (p< .05-.001) lower residual Cr(VI) concentrations within 24 h hydraulic retention time (HRT). Chromate removal increased significantly (p< .05) as the number of beads of immobilized spore/mycelia increased from 10 to 100; the increase in Cr(VI) removal ranging from 40.3% to 47.9% with 10 beads and 97.4% to 98.6% with 100 beads. Similarly, tannic acid removal by spores and mycelia of the fungi was significantly (p< .05) enhanced by immobilization. Repeated use of the alginate entrapped spores/mycelia of both fungi up to 3 cycles of 72-h HRT showed no significant change in their ability to carryout Cr(VI) removal.