Fig. 1

3-D response surface plots showing the interactive effect of two factors on a selected response while keeping the third factor fixed at its central value. a Yield of biosurfactants as function of temperature and molasses concentration; b surface tension as function of temperature and molasses concentration; c inhibition diameter as function of temperature and molasses concentration; d surface tension as function of temperature and peptone concentration; e inhibition diameter as function of temperature and peptone concentration; f yield as function of temperature and peptone concentration