Biosurfactant Producing Bacteria with Tensoactive and Emulsifying Properties Isolated from Palm Oil Mill Effluent

Abstract

This study introduces potential biosurfactant producing bacteria found in agro-based wastewater generated by palm oil mills. A total of 38 potential biosurfactant producing bacteria isolated from palm oil mill effluent were qualitatively screened for its tensoactive properties using drop collapse and oil spreading tests. Eleven of the 38 isolates exhibited high surface activity through the drop collapse test. The 11 isolates also exhibited clear zones ranging between diameters 2 to 3 cm through oil spreading test which indicated biosurfactant production. Further evaluations were performed quantitatively for all the 11 isolates in relation to their ability in reducing surface tension and emulsifying capability. Results from Du Nouy ring test demonstrated that the isolates successfully reduced surface tension of water from 72 mNm-1 to below 40 mNm-1. When tested for emulsifying properties, these isolates displayed high emulsifying activity indicating the presence of biosurfactant production. These 11 isolates namely R06, R07, R08, R10, S08, S09, S10, S11, S12, S15 and S17 were selected and identified using 16S rDNA gene sequence analysis. The results suggested that the isolates belong to the genus Bacillus.