Simultaneous separation and quantitation of three phytosterols from the sweet potato, and determination of their anti-breast cancer activity.

The present study provides the method for simultaneous separation and determination of concentration and evaluates anti-breast cancer activity of three phytosterols from the sweet potato (Ipomoea batatas L.): daucosterol linolenate (DLA), daucosterol linoleate (DL), and daucosterol palmitate (DP). A cell viability assay revealed that the three phytosterols had a stronger inhibitory effect on MCF-7 than MDA-MB-231 breast cancer cell line, and had no effects on non-tumorigenic MCF-10A cells. In vivo experiments demonstrated that DLA, DL, and DP suppressed tumor growth in MCF-7 xenograft breast cancer model in nude mice. Given the anti-breast cancer activity of DLA, DL, and DP, an HPLC method for the determination of their content in the sweet potato was developed. The method had satisfactory linearity (R² = 0.9992-0.9999). The limits of detection (LOD) were in the range of 2.5-10 μg/mL, the limits of quantification (LOQ) were 5-25 μg/mL, and the recovery rates were 97.64-103.02%. Additionally, the HPLC method was successfully validated in eight sweet potato cultivars. This novel technique can be applied for the determination of DLA, DL, and DP in the sweet potato.