Impact of substrates on heat capacity of lyophilised biomass of Fusarium
oxysporum associated with cyanidation wastewater
Abstract
Cyanide is a well-known constituent of mine wastewater which can be
degraded by various process. However, due to cost and environmental
challenges, microbial degradation seems to be the most effective
process. When wastewater is treated with microorganisms, process
performance should not only be based on toxicant degraded but also on
the impact of the toxicant on the physical properties of the
microorganisms. Heat capacity of lyophilised biomass of Fusarium
oxysporum was measured using modulated differential scanning
calorimeter. The heat capacity for F. oxysporum grown in cyanidation
wastewater was 1.1982, 1.077 and 1.143 J K-1 g-1 on glucose (GA), Beta
vulgaris (BA) and cyanide supplemented with Beta vulgaris (BCN),
respectively at 298.15 K and 1 atm. The enthalpy of formation of dry
biomass are -297.58, -233.07 and -278.60 kJ/C-mol for BA, BCN and GA,
respectively. These values were found to be within the range of some
biological molecules. The presence of cyanide in the wastewater
minimally affected the thermodynamic property of the dried biomass of F.
oxysporum.