Callus Induction and Determination of Iridoid Glycosides from Barleria prionitis Linn Leaf Explants

Callus cultures of Barleria prionitis Linn were established from leaf explants in Murashige and Skoog (MS) medium supplemented with various combinations of a-Naphthalene acetic acid (NAA) and 6-benzylaminopurine (BA). The explants developed compact greenish calluses in the presence of NAA (1.0 mg/L) and BA (0.5 mg/L). The growth of calluses was measured over 60 days. Maximum dry biomass, 0.143 g, was obtained at 50 days. Calluses were extracted with methanol to examine the presence of the iridoid glycosides having biological activity in intact plants. The methanol extracts were further separated by solvent-solvent extraction to give dichloromethane and n-butanol solubles or n-hexane, chloroform and n-butanol solubles. Each soluble was analyzed by TLC (thin layer chromatography) and HPLC (high pressure liquid chromatography). The n-hexane and chloroform solubles or dichloromethane solubles did not contain glycosides, but the n-butanol solubles showed the existence of glycosides on the TLC plate sprayed with p-anisaldehyde-sulfuric acid reagent. However, the n-butanol solubles in the methanol extracts of callus contained neither of the iridoid glycosides (8-O-Acetyl shanzhiside methyl ester (barlerin) and shanshiside methyl ester) present in intact plants. However, a glucoside was detected in the n-butanol solubles from the methanol extracts of callus by TLC. This study also attempted to determine the anticancer activity of methanol extracts from B. prionitis L. However, the methanol extracts were found to be inactive