Bioguided chemical characterization of pequi (Caryocar brasiliense) fruit peels towards an anti-diabetic activity

• Published in: Food chemistry Vol. 345; p. 128734
• Main Authors: Caldeira, Alisson S.P., Mbiakop, Ulrich C., Pádua, Rodrigo M., van de Venter, Maryna, Matsabisa, Motlalepula G., Campana, Priscilla R.V., Cortes, Steyner F., Braga, Fernão C.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.05.2021
• Subjects: Animals; Anti-diabetic potential; Blood Glucose - metabolism; By-product; Fruit - chemistry; Functional food; Hypoglycemic Agents - chemistry; Hypoglycemic Agents - pharmacology; In vitro assays; In vivo assay; Malpighiales - chemistry; Mice; Pequi fruit peels; Plant Extracts - chemistry; Plant Extracts - pharmacology; Polyphenols - analysis; Tandem Mass Spectrometry; Tannins; Tannins; Pequi fruit peels; By-product; Anti-diabetic potential; In vivo assay; In vitro assays; Functional food
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128734

•The antidiabetic potential of Caryocar brasiliense fruit peel extract was assessed.•Bioactive fractions were identified by cytokines and digestive enzymes inhibition.•UPLC-PDA-ESI-MS/MS analyses disclosed hydrolysable tannins in the active fractions.•A corilagin and geraniin rich fraction reduced glycaemia in starch tolerance test.•Fruit peels have potential for developing functional foods to manage type-2 diabetes. Pequi fruit peels are an underexploited source of polyphenols. The anti-diabetic potential of an extract and fractions from the peels were evaluated in a panel of assays. The extract and fractions thereof inhibited the release of cytokines involved in insulin resistance – TNF, IL-1β, and CCL2 – by lipopolysaccharide-stimulated THP-1 cells. The ethyl acetate fraction inhibited in vitro α-glucosidase (pIC50 = 4.8 ± 0.1), an enzyme involved in the metabolization of starch and disaccharides to glucose, whereas a fraction enriched in tannins (16C) induced a more potent α-glucosidase inhibition (pIC50 = 5.3 ± 0.1). In the starch tolerance test in mice, fraction 16C reduced blood glucose level (181 ± 10 mg/dL) in comparison to the vehicle-treated group (238 ± 11 mg/dL). UPLC-DAD-ESI-MS/MS analyses disclosed phenolic acids and tannins as constituents, including corilagin and geraniin. These results highlight the potential of pequi fruit peels for developing functional foods to manage type-2 diabetes.