Isolation and quantitative analysis of physalin D in the fruit and calyx of Physalis alkekengi L

Physalin D was isolated from the methanol extract of Physalis alkekengi L. fruits by combination of different chromatographic methods (CPC, TLC, HPLC). The structure was elucidated based on ¹H and ¹³C NMR spectral analysis with the aid of 2D-correlation spectroscopy (¹H, ¹H-COSY, HSQC and HMBC) and comparison with literature data. The quantity of physalin D in mature and immature fruits and calyces was determined by RP-HPLC-UV method. Among the studied samples, immature calyx showed the highest content of physalin D (0.7880 ± 0.0612%), while mature calyx contained 4 times less amount (0.2028 ± 0.016%). The physalin D content of the fruit was much lower; immature fruits contained 0.0992 ± 0.0083% physalin D and mature fruits 0.0259 ± 0.0021%. The antiproliferative activity of the CHCl₃ extract and its fractions was tested on three cancer cell lines (HeLa, MCF-7 and A431). The antiproliferative activity of physalin D is discussed with regard the published data.