Study of nutritional quality of pomegranate (Punica granatum L.) juice using ¹H NMR-based metabolomic approach: A comparison between conventionally and organically grown fruits

Pomegranate is an edible fruit with a valuable content of bioactive molecules. This work describes the metabolomic profiling of pomegranate samples collected from conventional and organic cultures by using a combined ¹H NMR-based and multivariate analysis protocol. The results of Principal Component Analysis (PCA) and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) revealed that pomegranate juices obtained from plants grown organically contained higher amounts of acetic acid, alanine, arginine, fumaric acid, GABA, galactose, glutamine, histidine, isoleucine, lactic acid, leucine, malic acid, mannose, methionine, phenylalanine, proline, sucrose, threonine, trigonelline, tyrosine, and valine than those obtained from fruits grown conventionally. Contrarily, pomegranate juices from plants grown under conventional conditions had significantly higher concentrations of acetone, aspartic acid, and ethanol than those obtained from fruits grown organically. These results suggested that plants growing conventionally experienced a kind of physiological stress. The endogenous levels of essential amino acids, organic acids and phenolic content support the fact that pomegranate samples grown under organic conditions have better nutritional quality than those grown under conventional conditions.