Plant derived components have attracted particular attention as an alternative source to battle several diseases including cancer. The variation in the climate, the geographical location and the rich ethnomedicinal traditions has made the Darjeeling Himalayas an abode of invaluable repository of traditional medicinal plants. In this study, we explored the in vitro anticancer properties of traditionally used medicinal plants from the Darjeeling hills against different human cancer cell lines. The ethanolic leaf extracts of 30 medicinal plants were tested for their cytotoxicity against human breast adenocarcinoma cell line (MCF 7), human hepatocarcinoma cell line (HepG2) and human cervix adenocarcinoma cell line (HeLa). The cytotoxicity was evaluated by performing MTT assay, trypan blue exclusion assay and morphological assessment under phase contrast inverted microscope. For the extracts which tested positive, IC50 (the concentration that inhibited cell growth by 50%) was calculated. The extract(s) were further subjected to Thin Layer Chromatography (TLC) to determine their phytochemical profile. Out of the 30 plant extracts tested, five plants, Artemisia indica, Eupatorium odoratum, Eupatorium adenophorum, Maesa macrophylla and Phlogacanthus thyrsiformis showed a > 50% growth inhibition of cancer cell lines at a concentration of 50 μg/ml. The sensitivity to different extracts varied according to the cell type under investigation. Of these plants, Maesa macrophylla, exhibited the most potent cytotoxicity against HeLa and MCF7 cell with IC50 values of 9.55 μg/ml and 16.19 μg/ml respectively. Phytochemical analysis revealed the presence of coumarins, flavonoids, tannins, saponins, steroids and terpenes. This is perhaps the first report of screening of traditional medicinal plants from Darjeeling district in West Bengal, India, for their cytotoxic activity against three human cancerous cell lines MCF7, HeLa and HepG2. The extracts of Maesa macrophylla significantly inhibited the growth of HeLa and MCF7 cancerous cell lines and constituted of multiple known biologically active compounds. The present study may provide the landmark for further exploration of M. macrophylla for its potent anticancer constituents.

Lagerstroemia speciosa (L.) Pers. has medicinal importance. Bioactive phytochemicals isolated from different parts of L. speciosa, have revealed hypoglycemic, antibacterial, anti-inflammatory, antioxidant and hepato protective properties. Despite one report from Philippines detailing the use of L. speciosa as curative for fever and as well as diuretic, there is no experimental evidence about the hepatoprotective activity of the flower extracts. Several spectroscopic methods, including GC–MS, were used to characterize phytochemicals present in the petal extract of L. speciosa. Ethanol extract of petals was evaluated for anti-oxidant and free radical scavenging properties by using methods related to hydrogen atom transfer, single electron transfer, reducing power, and metal chelation. This study has also revealed the in vitro antioxidant and in vivo hepatoprotective properties of petal extract against carbon tetra chloride (CCl4)-induced liver toxicity in Swiss albino mice. Hepatoprotection in CCl4 -intoxicated mice was studied with the aid of histology and different enzymatic and non-enzymatic markers of liver damage. Cytotoxicity tests were done using murein spleenocytes and cancareous cell lines, MCF7 and HepG2. GCMS of the extract has revealed the presence of several potential antioxidant compounds, of them γ-Sitosterol and 1,2,3-Benzenetriol (Pyrogallol) were the predominant ones. The antioxidants activities of the flower-extract were significantly higher than curcumin (in terms of Nitric oxide scavenging activity; p = 0.0028) or ascorbic acid (in terms of 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) assay; p = 0.0022). The damage control by the flower extract can be attributed to the reduction in lipid peroxidation and restoration of catalase activity. In vitro cytotoxicity tests have shown that the flower extract did not affect growth and survivability of the cell lines. It left beyond doubt that a flower of L. speciosa is a reservoir of antioxidant and hepatoprotective agents capable of reversing the damage inflicted by CCl4-intoxication. Results from the present study may be used in developing a potential hepato-protective health drink enriched with antioxidants from Lagerstroemia speciosa (L.) Pers.