Cytotoxic activity of the traditional Thai medicinal plant preparation Benjakul and 4 isolated compounds

Benjakul (BEN), a Thai traditional medicine preparation, is composed of five plants, Piper chaba fruit [PC], Piper sarmentosum root [PS], Piper interruptum stem [PI], Plumbago indica root [PL] and Zingiber officinale rhizome [ZO]. It is a balanced health preparation in Thai traditional medicine. From selective interviews of folk doctors in Southern Thailand, it was found that Benjakul was used as the adaptogen drug for cancer patients [1]. These plants and the preparation have been selected to study cytotoxic activity against three human cancer cell lines, large lung carcinoma (CORL23), prostate cancer cell lines (PC3) and liver cancer cell lines (HepG2) using the SRB assay [2]. From the Benjakul preparation also pure compounds were isolated and their cytotoxic activity was tested. From the EtOH extract four compounds were isolated [gingerol (Gin), shogaol (Sho), plumbagin (Plu) and piperine (Pip)]. The results shown below can support the usage of Benjakul to treat cancer patients. The four compounds isolated can be markers for standardization of the preparation.

Table. IC₅₀ values (µg/mL) against cell lines and antioxidant activity [EC₅₀ value (µg/ml)] of Benjakul and some of its ingredients

Plant extracts	PC	PS	PI	PL	ZO	BEN	Gin	Sho	Plu	Pip
CORL23	15.8	32.9	18.4	3.4	7.9	19.8	26.2	2.1	0.5	10.5
PC3	19.7	45.8	27.8	9.2	9.9	29.8	9.6	3.7	0.5	12.7
MCF-7	35.7	69.5	62.4	40.8	31.2	33.2	8.5	4.1	9.4	0.47

Acknowledgement: Faculty of Medicine, Thammasart University for the financial support

References: [1] Itharat, A. et al. (1998) Wisdom of Southern Thai Traditional Doctors. Prince of Songkla University, Songkla, p.126–129. [2] Skehan, P. et al. (1990) J. Natl. Cancer Inst., 82: 1107–1112.