Mutamba (Guazuma ulmifolia Lam.) fruit as a novel source of dietary fibre and phenolic compounds

This study covers the proximate and phytochemical composition of mutamba (Guazuma ulmifolia Lam.) fruit. This fruit showed high dietary fibre (36.9%) and low moisture (10.0%) contents which justify its hardness and dryness. Nevertheless, this fruit is very appreciated due to its sweet pulp (high sucrose content, 16.3%) and attractive taste. The soluble and insoluble-bound phenolic compounds from mutamba fruit were analysed by using liquid chromatography coupled to tandem mass spectrometry (LC-MS). LC-MS identified 26 compounds. Mutamba fruit was composed mainly by soluble flavonoids (1385.9 µg/g dw), namely proanthocyanidins, and aglycones and glycosylated flavonoids. Procyanidin trimer C1 (972.8 µg/g dw) followed by procyanidin dimer B2, rutin, epicatechin, and hyperoside were the main soluble phenolics, accounting 1435.5 µg/g dw. Conversely, the main cell wall bound phenolics (228.8 µg/g dw) were catechin, followed by protocatechuic acid, epicatechin, and gallic acid. In conclusion, mutamba fruit may be a novel source of dietary fibre and bioactive phenolic compounds.