Effect of biosurfactant on thiocyanate degradation by automobile service station soil isolates Brachybacterium sp. and Bacillus albus

Abstract

This study investigated the effect of biosurfactants on the microbial degradation of thiocyanate (SCN−), with the aim of finding a sustainable solution for the treatment of industrial wastes containing thiocyanate and related compounds. Isolates VK8 and VT7, screened from amongst 40 automobile service station soil isolates, showed promising growth in the presence of high thiocyanate concentration (500 mg/L). Biosurfactant BS1-S1W from isolate S1W (Brucella intermedia) enhanced the degradation of SCN− by Brachybacterium sp. (VT7) and Bacillus albus (VK8) by 92% and 95%, respectively, at 200 mg/L. Biosurfactant BS2-VO6 from isolate VO6-2 (Brevundimonas naejangsanensis) caused increment in the reduction of SCN- by 88% and 80%, respectively. FTIR and LC-MS analysis of the purified biosurfactants confirmed their glycolipid nature. Enhanced effect of biosurfactant was more pronounced at higher KSCN concentration. Little is known about the effects of microbial products on the enhancement of microbial biodegradation of SCN−. Production and application of biosurfactant from B. naejangsanensis has not been reported earlier and hence can lead to more effective biological agents of enhanced biomedical and environmental relevance. This is the first report of the application of Brachybacterium and B. albus for thiocyanate degradation and the effect of biosurfactant on the same.