In vitro assessment of the antihyperglycemic and antioxidant properties of araçá, butiá and pitanga

Native fruits have been known as a great source of bioactive compounds with potential biological effects. The aim of this study was to investigate the α-glucosidase inhibition and antioxidant activities of araca (Psidium cattleianum Sabine), butia (Butia odorata (Barb. Rodr.) Noblick) and pitanga (Eugenia uniflora L.) and relate their chemical composition with the observed biological activity. Samples of mature fruits were extracted with ethanol and the observed biological activities were dependent of the species and concentration as well. Aracas were the strongest α-glucosidase inhibitors (IC50 value of 25.4 ± 0.7 and 31.8 ± 0.7 µg/ml, respectively). Pitangas showed antiradical activities against DPPH, hydroxyl and nitric oxide radicals. Orange pitanga and butia from Santa Vitoria do Palmar were the most active concerning anion superoxide radical. All fruits are rich in total phenolic compounds with values in the range of 454.5 ± 17.3–908.3 ± 60.8 mg of equivalents of chlorogenic acid/100 g fresh weight. Purple pitanga stood out due to their levels of anthocyanins and carotenoids. Fruits showed similar amounts of total sugars, aracas and pitangas showed higher levels of reducing sugars while butias were the richest ones in non-reducing sugars. Fruits with lower IC50 values for α-glucosidase inhibition were correlated with higher concentrations of reducing sugars, phenolic compounds, anthocyanins and carotenoids and grouped by principal component analysis (PCA). The obtained results indicate that these native fruits are promising sources of α-glucosidase inhibitors and antioxidants that can be used to control glycemia in patients with type 2 Diabetes mellitus.