The use and commercial applications of biosurfactants in the petroleum industries have been
raised during the past decades. Marine bacteria and their efficiency in crude oil recovery has
been less studied than terrestrial strain, hence this present study. A novel marine bacterium
Bacillus simplex having promising biosurfactant production was isolated from a petroleum
hydrocarbon-contaminated coastal sea sediment samples of Nagapattinam fishing harbor,
Tamil Nadu, India. This strain showed most economical biosurfactant production with an
agro-industrial waste substrate, sunflower oil cake at 54th h time incubation along with the
cultural conditions of 20 ppt salinity, 35 °C temperature, and pH 7. The produced biosurfactant
was purified, which was accounted at 908 ± 7 mg/L on dry weight basis. The biosurfactant
was identified as lipopeptide with a molecular mass of 1111.1 Da which was deduced using
TLC, biochemical estimation methods, FT-IR, NMR, and MALDI-TOF MS analysis. Furthermore,
this purified lipopeptide surfactant showed consistent and enhanced crude oil recovering
efficiency under different salinity conditions (0–30%). Based on the above facts, the isolated
novel marine bacterium proved its cheaper production of novel biosurfactant and its promising
oil recovering efficiency even at hypersaline conditions. Further, this is the first report of a
biosurfactant from the bacterium Bacillus simplex.