Potential biological deodorisation of Butyric acid by aerobic bacterial species of Bacillus genus under different pH conditions

Abstract

Waste volatile compounds, such as butyric acid, generated from pit latrines may cause discomfort to pit latrine users and they have undesirable impacts on sanitation promotion efforts and public health. The purpose of this work was to isolate and identify highly efficient deodorant butyric acid bacteria and investigate their feasibility of biologically removing butyric acid from enriched liquid medium under different pH conditions. The determination of the ability of these bacterial strains on removal of butyric acid was at the concentration of 1000 mgL-1 in MSM. The experiment was designed in a batch reactor under aerobic condition by shaking in a temperature controlled incubator at orbital shaking speed of 110 rpm and of 30 oC and initial pH was adjusted to 7.0. The results showed that these bacterial strains were identified as Bacillus cereus, Lysinibacillus fusiformis, Bacillus subtilis and Bacillus methylotrophicus. The bacterial strains were capable of growth and degrading butyric acid at a wide range of initial pH values but the optimal growth and butyric acid degradation was achieved at neutral pH. Complete butyric acid degradation was achieved within 20-24 h. The bacterial strains have proved to be potential candidates for the development of biodeodorization systems for pit latrines.