Metabolomic study of daytime and nighttime extrafloral nectars of Cleome gynandra L. via 1H NMR combined with chemometrics

Abstract

Extrafloral nectars are considered rewards the plant offers to organisms that can act as protectors. These substances are nutritious aqueous solutions, which reinforces a possible mutualistic relationship. Since the plant metabolism differs according to the period evaluated (day or night), the composition of the nectars should also be distinct, which may result in different plant-animal relationships. In this context, the present study aimed to evaluate the chemical composition of the extrafloral nectars of the plant Cleome gynandra L., collected in the morning and evening periods. The chemical profiles were determined via ¹H Nuclear Magnetic Resonance spectroscopy. The results indicated the majority presence of carbohydrates, followed by amino acids and organic acids. The results also allowed the identification of a pattern of change in the identity of the carbohydrates offered during the day and night, suggesting that this change may be relevant to the relationship between plants and insects.