Agroindustrial wastes as unconventional substrates for growing of bacillus strains and production of biosurfactant

The study was aimed at the development of economical methods for biosurfactant production by the use of unconventional substrates. The research investigated the potential of utilising agroindustrial wastes to replace synthetic media for cultivation of Bacillus strains and biosurfactant production. In total, 21 of the waste products from dairy, sugar, fatty, and fruit and vegetable processing industries, breweries, distillery were examined. Three bacterial strains were identified by 16S rRNA gene sequencing: Bacillus subtilis (I'-1a), Bacillus sp. (T-1), Bacillus sp. (T'-1). Biosurfactant production was examined in an indirect way by measuring of surface tension (ST), blood agar lysis, oil spreading and drop collapsing tests. The best unconventional substrates for bacteria growing and biosurfactant production at 30 °C under aerobic conditions were molasses, brewery effluents, and fruit and vegetable decoction from the processing factory.