Cytotoxic Saponin against Lung Cancer Cells from Dioscorea birmanica Prain & Burkill
Nuanjan Jaiaree MSc*, Arunporn Itharat PhD**, Kamman Kumapava MD***
Affiliation : * Student of Doctor of Philosophy, Faculty of Medicine, Thammasat University, Pathumthani, Thailand ** Department of Applied Thai Traditional Medicine, Faculty of Medicine, Thammasat University, Pathumthani, Thailand *** Department of Internal Clinic Medicine, Faculty of Medicine, Thammasat University, Pathumthani, Thailand
Objective : To investigate the cytotoxic activity against lung cancer cells of Dioscorea birmanica Prain & Burkill extract and
its compounds.
Material and Method: Cytotoxic activity was tested against two types of lung cancer cell line (A549 and CORL-23), one type
of normal lung cell (MRC-5) by sulforhodamine B assay. Bioassay guide fractionation was used for isolating cytotoxic
compounds. The structure elucidation of active ingredients was proven by spectrophotometry technique.
Results : The results found that the ethanolic extract of Dioscorea birmanica Prain & Burkill (DBE) showed high cytotoxic
activity against lung cancer cells; A 549 and COR-L23 (IC50 = 7.45 + 0.31, 8.71 + 0.29 μg/ml, respectively) but no cytotoxic
activity against normal cancer cells MRC-5 (IC50 = 94.76 + 1.25 μg/ml). Six fractions from DBE were isolated by vaccuum
liquid chromatography with ordering polarity of solvent and were coded as DB1-DB6, respectively. The fraction DB5 showed
high cytotoxic against A 549 and COR-L23 (IC50 = 6.14 + 0.08 and 16.44 + 1.23 μg/ml, respectively) but less toxic to normal
cell. Diosgenin-3-O-α-L-rhamnosyl (1→2)-β-D-glucopyranoside or Prosapogenin A of dioscin (DBS1) was isolated from
DB5 fraction and had highest cytotoxic activity against those two types of lung cancer cells (IC50 = 1.81 + 0.03, 1.84 + 0.05
μg/ml), respectively) but less cytotoxic against normal lung cells MRC-5 (IC50 = 37.09 + 0.67 μg/ml).
Conclusion : The steroid saponin from Dioscorea birmanica showed cytotoxic activity against human lung cancer cells but
less toxic against normal lung cells.
Keywords : Cytotoxic activity, Dioscorea birmanica Prain & Burkill, Lung cancer cell
