Metabolic Alterations of Withania somnifera (L.) Dunal Fruits at Different Developmental Stages by NMR Spectroscopy

Introduction - Withania somnifera (Ashwagandha) is a high-value Ayurvedic medicinal plant and an important constituent of several dietary supplements. In order to substantiate the health claims, the herb has drawn considerable scientific attention. Objective - The objective of the study was to investigate the alterations in primary and secondary metabolites of W. somnifera fruits during its maturity using NMR spectroscopy. Methodology - Fruits at different stages of development from one week after fertilisation until maturity, classified in seven developmental stages, were analysed by a combined use of one-and two-dimensional NMR experiments. Results - Seventeen metabolites were characterised and quantified from non-polar and polar extracts of different fruit development stages of W. somnifera. The principal component analysis of polar metabolites at different stages could be grossly classified into three metabolic phases, viz. initial phase, developmental phase and maturation phase. Conclusion - Qualitative and quantitative analysis of metabolites in W. somnifera fruits indicated specific stages when fruits can be harvested for obtaining substantial bioactive ingredients for desirable pharmacological activity. This study potentially provides a complementary tool for quality control of herbal medicinal products when W. somnifera fruits are used. Copyright (C) 2011 John Wiley & Sons, Ltd.