Phytochemicals, Functional and Physiochemical Properties of Selected Unexploited Fruits in Sri Lanka

Abstract

As a tropical country with high biodiversity, Sri Lanka has a diversified variety of fruits, however most of them remain unexploited. Unfortunately, most Sri Lankans are not aware of those neglected fruit crops and their nutritional value and health benefits. Therefore, this study was carried out to determine the total antioxidant capacity, bioactive compounds and physiochemical properties of nine selected underutilized fruit species in Sri Lanka. Extracts of selected nine unexploited fruits namely, Syzygium cumini (Java plum), Ardisia elliptica (Shoebutton fruit), Eugenia uniflora (Surinam cherry), Antidesma alexiteria (Ceylon bignay), Dovyalis hebecarpa (Ceylon gooseberry),  Malpighia emarginata (Barbados cherry), Morus alba (Mulberry),  Flacourtia indica (Governor’s plum) and  Antidesma bunius (Bignay) were assessed for their total phenolic content (TPC), total flavonoid content (TFC) and total antioxidant capacity (TAC) as well as physiochemical properties. TPC, TFC and TAC were determined by Folin-ciocalteu method, a colourimetric method and ferric reducing antioxidant power (FRAP) assay respectively. The fresh weight (FW), moisture content and total soluble solid (TSS) were also determined.  Statistical Analysis was done by analysis of variance (ANOVA) followed by Tukey Multiple Range Test using SAS. The highest fresh weight was observed in Eugenia uniflora (7.31 ± 0.60 g) whereas, the highest moisture content was recorded in Morus alba (88.81 ± 0.48 %). Flacourtica indica had the highest TSS value (19.95 ± 0.71%). Malpighia emarginata had significantly the highest TAC (2623 ± 43.37 mg TE/100 g FW) and TPC (1624.01 ± 71.45 mg GAE/100 g FW) whereas, significantly high TFCs were observed in Flacourtica indica (1374.03 ± 222.61 mg RE/100 g FW) and Syzygium cumini (1305.97 ± 202.17 mg RE/100 g FW). This study concluded that Malpighia emarginata, Syzygium cumini and Flacourtica indica had potent sources of bioactive compounds and antioxidants.