Abstract:
The present study aims at developing an e cient bacterial consortium to biodegrade
butyric acid, one of the odor-causing compounds that contribute significantly to pit latrine malodors.
Six bacterial strains isolated from pit latrine fecal sludge were selected for the study. Nineteen
bacterial consortia of di erent combinations were artificially constructed. The individual bacterial
strains and bacterial consortia were compared by culturing in mineral salt medium supplemented
with 1000 mg/L butyric acid as a sole carbon and energy source at pH 7, 30 C, and 110 rpm under
aerobic growth conditions. A co-culture of Serratia marcescens and Bacillus cereus was an e ective
bacterial consortium compared to individual component bacterial strains and other bacterial consortia,
in which 1000 mg/L butyric acid was completely degraded within 16 h of incubation. A temperature
of 30 C and pH 7 were found to be optimum for the maximum degradation for both S. marcescens
and B. cereus. The inoculation sizes of 2.0 and 2.5 were optimal for the maximum degradation for
B. cereus and S. marcescens, respectively. The study provides insights that will be of substantial help in
the development of e ective biological treatment technologies for pit latrine odor to change the pit
latrine user community’s and would be users’ perception of pit latrines.
