Abstract: Different agricultural waste peels were assessed for
their suitability to be used as primary substrates for the
bioremediation of free cyanide (CN-) by a cyanide-degrading fungus
Aspergillus awamori isolated from cyanide containing wastewater.
The bioremediated CN- concentration were in the range of 36 to 110
mg CN-/L, with Orange (C. sinensis) > Carrot (D. carota) > Onion
(A. cepa) > Apple (M. pumila), being chosen as suitable substrates
for large scale CN- degradation processes due to: 1) the high
concentration of bioremediated CN-, 2) total reduced sugars released
into solution to sustain the biocatalyst, and 3) minimal residual NH4-
N concentration after fermentation. The bioremediation rate constants
(k) were 0.017h-1 (0h < t < 24h), with improved bioremediation rates
(0.02189h-1) observed after 24h. The averaged nitrilase activity was
~10 U/L.