Lactonic Sophorolipids Increase Tumor Burden in Apcmin+/- Mice

Sophorolipids (SL) are amphiphilic biosurfactant molecules consisting of a disaccharidesophorose with one fatty acid at the C1 position and optional acetylation at the C6’and C6”positions. They exist in a closed ring lactonic (LSL) or open acidic (ASL) structure Sophorolipidsare produced in crude mixtures in economically viable amounts by the yeast Starmerellabombicola and used in a variety of consumer products. Varying levels of antiproliferativeand anti-cancer activity of crude sophorolipid mixtures are described in a number of tumor cell lines in vitro. However, significant inter-study variation exists in the composition of sophorolipid species as well as other biologically active compounds in these mixtures, which makes interpretation of in vitro and in vivo studies difficult.We produced a 96% pure C18:1 lactonic sophorolipid that dose-dependently reduces the viability of colorectal cancer, as well as normal human colonic and lung cell lines in vitro. Oral administration of vehicle-only; or lactonic sophorolipids (50 mg/kg for 70 days), toApcmin+/- mice resulted in an increase in the number (55.5 ± 3.3 vs 70.50 ± 7.8: p <0.05)and size (modal size 2mm vs 4mm) of intestinal polyps. Lactonic administration resulted in a systematic effect via reduced hematocrit (49.5 ± 1.0 vs 28.2 ± 2.0 vs: p