NMR-based metabolomic analysis to identify changes in the metabolite profile of three M. oleifera genotypes grown in an open hydroponic system

Abstract

Moringa (Moringa oleifera) is one of the worlds most useful plants. Different parts of the M. oleifera tree contain a rich profile of important minerals, proteins, vitamins, and various important bioactive compounds. As an important medicinal plant, the tree proved to exhibit various therapeutic activities such as anti-cancer, antihypertension, anti-diabetes, anti-epilepsy and many more. However, there are differences in the metabolite composition of medicinal plants raw materials due to seasonal variation, cultivation practices, and post-harvest processing. The main objective of this study was therefore to determine the effect of harvesting frequencies and associated seasonal conditions on the bioactive compound profile of M. oleifera cultivars grown in a hydroponic system in a shade net structure. 1H NMR was used for data acquisition, and MestReNova software was used for the pre-processing of the spectral data. Multivariate data analysis by means of PCA and OPLS-DA was conducted using SIMCA software. The OPLS-DA analysis showed separation of some samples, which allowed construction of a contribution plot. The contribution plot showed that the intensity (or concentration level) changes in aliphatic, sugar and aromatic regions contributed to the separation of the samples. These results provide insight into the effect of seasonal conditions and harvesting practices on the metabolite profile and associated medicinal activity of M. oleifera.