NMR-metabolomic analysis of banana (Musa acuminata) plants in response to λ-carrageenan treatment

Supplementation with λ-carrageenan has been demonstrated to enhance plant growth, including in banana plants. However, the underlying mechanisms behind this observation remain poorly understood. This study aimed to investigate the mechanism by which λ-carrageenan promotes banana plant growth using Nuclear Magnetic Resonance (NMR) spectroscopy-based metabolomic profiling. The metabolite profile of λ-carrageenan-treated banana plants revealed elevated concentrations of phosphatidylcholine, glucose 6-phosphate, glycine, fructose, isoleucine, glycerol, glucosamine 6-phosphate, choline, β-glucose, and α-glucose. Conversely, levels of α-linolenic acid, ethanol, and 3-hydroxy-3-methylglutaryl-CoA were reduced in the treatment group. Biochemical analysis further confirmed that λ-carrageenan treatment increased total carbohydrate content and glutamate synthase activity in banana plants, consistent with the observed changes in metabolite levels. Overall, these findings suggest that λ-carrageenan enhances banana plant growth by modulating carbohydrate metabolism, lipid metabolism, amino acid biosynthesis, glycolysis, and terpenoid biosynthesis. This new insight into the plant growth-stimulating effects of λ-carrageenan may be valuable for the development of next generation fertilisers.