Comparative Biological Activities of Five Thai Medicinal Plants Called Hua-Khao-Yen

Abstract

Plants named ‘Hua-Khao-Yen’ are common ingredients in traditional cancer remedies
in Thailand and are best-selling medicinal plants in traditional drugstores. From the selective
interview found that Hua-Khao-Yen was found to comprise at least five species such as
Dioscorea membranacea Pierre (Dioscoreaceae) (DM), D. burmanica Prain ex Burkill
(Dioscoreaceae) (DB), Smilax corbularia Kunth (Smilacaceae) (SC), S. glabra Roxb.
(Smilacaceae) (SG), or Pygmeopremna herbacea Prain et Burkill (Verbenaceae)(PM). Three
in vitro bioassay were used to compare activities of these plants such as cytotoxic ,
antioxidant and antimicrobial activities.The extract procedures used were similar to those
practiced by Thai traditional doctors (water and ethanolic extraction). The SRB assay used to
test cytotoxicity against two types of human liver cancer cell line (HepG2). The lipid
peroxidation of liposomes assay was used to test for antioxidant activity of the 5 plant
extracts. Disc diffusion method were used for antimicrobial activity. The results found that
The ethanolic extracts of DB showed the highest cytotoxic activity against Hela
(IC50=28.060±6.338 μg/ml) and the ethanolic extracts of DM showed the highest cytotoxic
activity against HepG2 (IC50=18.539±2.371 μg/ml). The water extracts of these plants
showed no cytotoxic activity against two types of human cancer cell line. The ethanolic
extract of Dioscorea membranacea rhizome showed highest antioxidant activity (EC50= 8.09
μg/ml). and also showed the highest activity against with S. aureus , B.subtilis and E.floccosum