Anticancer efficacy of Luisia zeylanica Lindl., an epiphytic orchid from Eastern Ghats of Andhra Pradesh, India - an in vitro approach

The present study aims to evaluate the anticancer potentiality of Luisia zeylanica Lindl. against cancer cell lines. L. zeylanica belongs to the tribe Vandeae of subfamily Epidendroideae (Orchidaceae). The plants were collected from the wild and grown in the Botanic Garden of the Acharya Nagarjuna University. The shade-dried leaf sample of these plants was extracted with ethyl acetate and methanol solvents, the resultant extracts were filtered and then concentrated. Cytotoxic effect of these extracts against cancer cell lines, viz., MCF-7 (breast cancer cell line) and HeLa (cervical cancer cell line) was evaluated by MTT assay maintaining six concentrations of crude leaf extracts in triplicates. The results of MTT assay revealed that the percentage of viability of both the cell lines have been reduced with the increase of concentrations of leaf extracts. The viability % of cell lines in ethyl acetate and methanol extracts on MCF-7 cell lines at concentration of 100 µg mL^‑1 was found to be 44.44 and 36.39%, respectively. Similarly, for HeLa cell lines the viability was 40.93 and 39.65%. Methanol leaf extract showed most significant IC₅₀ value of 18.36 µg mL^‑1 on MCF-7 cell lines when compared to ethyl acetate (49.49 µg mL^‑1). Hence, the findings of this study proved that leaf extract of L. zeylanica has anticancer effect and this species could be exploited to develop the anticancer drugs.