Evaluation of Metabolic Changes in Fruit of Piper Sarmentosum in Various Seasons by Metabolomics Using Fourier Transform Infrared (FTIR) Spectroscopy

Abstract

Variation in metabolites of herbs, due to ontogenetic, ecotypic, genotypic and chemotypic factors, leads to inconsistency in herbal medicinal products, which is one the main challenges faced by natural product industry. Metabolomics detect, quantify and catalogue the time related metabolic processes of an integrated biological system. Therefore, present study aimed to use metabolomics to investigate time related metabolic changes in fruit of Piper sarmentosum in order to find the suitable time of harvesting the fruit to maintain consistency in efficacy and batch-batch reproducibility. The same size of the fruit was collected from the same location from April 2006 to August 2007 at an interval of two months. Each collection was regarded as a single independent batch. The dried fruit powder of each batch was analyzed in triplicate by FTIR spectrophotometer in potassium bromide pellets. The FTIR spectra of different batches were analysed by chemometrics, principal component analysis (PCA), to evaluate identification, classification and differentiation (ICD) using PerkinElmer application software. All the samples exhibited correlation (86.24 %) with reference to PCA 1 and 9.38 % on PCA2. The samples collected in November-December 2006 and July-August 2007 were grouped far from others on positive and negative side of the upper quadrants. These results indicated that the metabolic constituents in the samples varied in all the batches. However, correlation in the samples might be helpful to predicted consistency in pharmacological activity. The results of this study indicate that FTIR fingerprint profiles of the samples in combination with chemometrics is an effective tool of ICD which may be helpful for natural product industry to indemnify the quality and batch-batch reproducibility.