Discriminating the leaves of Ocimum sanctum Linn. conferring to their age by gas chromatographic fingerprint analysis assisted with multivariate analysis

Abstract

Ocimum species is having massive variations in their chemical composition that includes day time, terrestrial and cyclical variation according to the season etc. In this study, variation in overall essential oil constituents among matured, intermediate and young leaf samples of O. sanctum was studied. The leaf samples according to their age- matured, intermediate and young leaves were collected from three different plants at 11 a.m. each. Extract of collected leaf samples were then scrutinized using gas chromatographic technique having flame ionization detector (GC-FID). Result reveals that the noteworthy variance was observed in overall essential oil constituents of the leaf samples according to their age. The Average chromatographic fingerprint data of triplicate run for different leaf samples were then treated to multivariate methods such as hierarchical cluster analysis and principal component analysis. In this study, instead of considering one or two biomarkers, we have exasperated to obtain as many constituents in chloroform extracts of chosen leaf samples. Scree plot reveals that nine components were responsible for the whole variation. Score plot and dendogram efficiently discriminated all the three leaf types according to their age in different clusters. The outcome as an inference was, O. sanctum leaves according to their age exhibit variation in its chemical composition and developed tool can be used for routine quality control.