Abstract
The aim of this work was to study chemical structures and biological activities of rhamnolipids produced by Pseudomonas aeruginosa
B189 isolated from milk factory waste. The culture produced two biosurfactants, a and b, which showed strong activity and were identiWed as L-rhamnopyranosyl-L-rhamnopyranosyl--hydroxydecanoyl--hydroxydecanoate or Rha–Rha–C10–C10 and L-rhamnopyranosylL-rhamnopyranosyl--hydroxydecanoyl--hydroxydodecanoate or Rha–Rha–C10–C12, respectively. Both compounds exhibited higher
surfactant activities tested by the drop collapse test than several artiWcial surfactants such as SDS and Tween 80. Rhamnolipid a showed
signiWcant antiproliferative activity against human breast cancer cell line (MCF-7) at minimum inhibitory concentration (MIC) at
6.25g/mL while rhamnolipid b showed MIC against insect cell line C6/36 at 50g/mL.