Simple densitometric TLC analysis of plaunotol for screening of high-plaunotol-containing plants of Croton stellatopilosus Ohba

Abstract

Plaunotol, an anti-peptic diterpenoid present in the leaves of Croton stellatopilosus Ohba, was separated from other components of crude methanolic extracts and quantified by densitometric TLC. Validation of precision, repeatability, and accuracy showed the technique was reliable, with 98.7% recovery of externally added plaunotol. Crude extracts of different leaf samples could be applied directly to silica gel TLC plates without prior sample preparation or concentration of the extracts. Plates were chromatographed with chloroform-n-propanol 96:4 (v/v) as mobile phase then scanned at 220 nm. The results showed that the plaunotol content of the leaves of C. stellatopilosus was highly variable (range 0.14 to 0.79% w/w of dry weight). Although most (35%) leaf samples seemed to contain 0.3-0.4% plaunotol, 8% contained more than 0.6%. This densitometric TLC method could, therefore, be a useful tool for screening of high-plaunotol-producing C. stellatopilosus plants as effective sources of the compound. © 2009 Akadémiai Kiadó.