09-08-2013, 03:26 PM
In vitro anticancer effect of extracts from Mentha species
ABSTRACT
Mentha is a worldwide plant and contains several species which are used in traditional medicine and phytotherapy mainly for gastrointestinal disturbances. Many pharmacological and cytotoxic activities have been reported from Mentha species. Methanolic extracts and essential oils from six Mentha species viz. Mentha piperita, Mentha spicata, Mentha pulegium, Mentha longifolia, Mentha aquatica and Mentha crispa showed cytotoxicity against HeLa and HeP2 cancer cell lines. Mentha spicata (pahari pudina) is an important aromatic spice which could have potential antitumor activity as its aqueous extract showed cytotoxic effect in mouse fibrosarcoma Wehi-64 and human monocytic U937 cells. In this investigation, we examined the possible in vitro anticancer potential of four Mentha species (Mentha arvensis, Mentha longifolia, Mentha spicata, Mentha viridis) on eight human cancer cell lines (A-549, COLO-205, HCT-116, MCF-7, NCI-H322, PC-3 THP-1, U-87MG) via methanolic and aqueous extracts. The anticancer activity was determined by the cytotoxic potential of the test material at 100µg/ml. Cells were allowed to grow for 24 h on 96 – well flat bottom tissue culture plates. Cells were further allowed to grow in the presence of test material for 48 h. Cell growth was terminated by addition of 50% (w/v) tricarboxylic acid. Cells were stained with SRB dye. Excess dye was removed by washing with 1% (v/v) acetic acid and bound dye was dissolved in Tris buffer. OD was taken at 540nm and growth inhibition of 70% or above was considered active for our bioassay purpose in case of extracts. Results revealed that methanolic extracts derived from the whole plant of above mentioned Mentha species showed in vitro cytotoxic efficiency against COLO-205, MCF-7, NCI-H322, THP-1, however, aqueous extracts from the same species were found active against HCT-116 and PC-3. Our investigation suggests that these Mentha species possess certain constituents with cytotoxic properties that can be used for developing anticancer agents for cancer therapy.