Oroxylum indicum (L.) Kurz (Shyonak, Indian trumpet tree, Midnight horror) belongs to the family Bignoniaceae and has been used as a single drug or as a component of certain poly-herbal drug preparations in Indian Ayurvedic system of medicine. Oroxylum indicum is reported to contain flavonoids, namely, chrysin, oroxylin-A, scutellarin, and baicalein. Baicalein is reported to have anti-cancerous activity and inhibits proliferation of various cancer cell lines in vitro via induction of apoptosis. The aim of the present study is a comparative of the quantity of baicalein produced by various aerial parts of O. indicum from samples collected from Ranchi and Naukuchiyatal, India. Quantification of baicalein was done using reversed phase high performance liquid chromatography (RP-HPLC) and heavy metal analysis was performed using inductively coupled plasma optical emission spectrometry (ICP-OES). It was found that trees of O. indicum have high concentration of baicalein. Seeds from both Ranchi and Naukuchiyatal had the highest content of baicalein, that is, 15.1349±0.109 and 14.9839±0.078 mg baicalein/g DW, respectively, followed by leaf, stem bark and stem samples. In addition, accumulation of heavy metals like Cd, Li, Mg, Se, Pb and Zn was found in various aerial parts of O. indicum. Since baicalein has shown its effectiveness as a potent inhibitor to various cancer lines, hence the current study opens prospect for in vitro production of baicalein from O. indicum cells.
Keywords: Oroxylum indicum, baicalein, reversed phase high performance liquid chromatography (RP-HPLC), inductively coupled plasma optical emission spectrometry (ICP-OES).