## 5 Bioactivities  
### Antioxidant Activity (AOXA)  
As can be noticed in Table 3, lesser-consumed tropical fruits have shown significant AOXA. The AOXA of jackfruit, as determined with the 2.2\({}^{\prime}\)-azino-bis(3-ethylbenzothazoline-6-sulfonic acid) (ABTS\({}^{\bullet}\)) assay, is reported as IC\({}_{50}\) = 570, 23 and 762 mg dw/100 mL extract in pulp, peel, and seed, respectively. The results of DPPH\({}^{\bullet}\) are reported as 16 \(\mu\)M Trolox equivalents (TE)/100 g fw, 1.25 mg dw/mL and \(>\)10 mg dw/mL in pulp, peel, and seed, respectively. In the same way, an in vitro assay of \(\alpha\)-glucosidase inhibition was developed and indicated that peel extract inhibited about 11.8-fold, as compared to acarbose [22; 69]. AOXA values have been reported to positively correlate with the total phenolic compounds content in jackfruit when using the ABTS\({}^{\bullet}\) (R = 0.94, \(p\leq\) 0.001) and DPPH\({}^{\bullet}\) (R = 0.88, \(p\leq\) 0.001) assays, higher values than the correlation with ascorbic acid (R = 0.38 and R = 0.50, respectively) and anthocyanins (R = 0.36 and R = 0.19, respectively), suggesting that phenolic compounds other than anthocyanins, such as phenolic acids, tann acid and proanthocyanids, may be the most important contributors to the AOXA of this fruit [69]. Therefore, the results reveal the potential of jackfruit peel as a source of natural antioxidants and hypoglycemic agents. In vitro assays have shown that extracts from jackfruit pulp have ABTS\({}^{\bullet}\) radical scavenging capacity, with an inhibition of 11.7%. Jackfruit extracts have also shown a greater capacity to inhibit nitric oxide (NO\({}^{\bullet}\)) (75.3% inhibition) and superoxide anion (O\({}^{\bullet-}\)) (46% inhibition) than other fruits that are commonly known as good inhibitors of NO\({}^{\bullet}\) and O\({}_{2}\)\({}^{\bullet-}\), such as blueberries (44.2 and 10%), black raspberry (13.1 and 8.7%), grapes (66.9 and 43%) and red raspberry (37 and 43%). The capacity of jackfruit pulp extracts to stabilize DPPH\({}^{\bullet}\), ABTS\({}^{\bullet}\), NO\({}^{\bullet}\) and O\({}_{2}\)\({}^{\bullet-}\) has shown positive correlation with total phenolic content (R = 0.967, 0.621, 0.380 and 0.532), flavonoids (R = 0.30, 0.995, 0.685 and 0.802) and proanthocyanidins (R = 0.902, 0.755, 0.201 and 0.371). This suggests that the stabilization of the DPPH\({}^{\bullet}\) radical is mainly due to the presence of total phenolic compounds, including proanthocyanidins and the stabilization of the ABTS\({}^{\bullet}\) radical is due to the presence of the flavonoids and proanthocyanidins, while the inhibition of NO\({}^{\bullet}\) and O\({}_{2}\)\({}^{\bullet-}\) is due to the presence of flavonoids [79]. AOXA of many has been reported as 393.81 and 113.06 \(\mu\)mol TE/100 g fw for ABTS\({}^{\bullet}\) and DPPH\({}^{\bullet}\), respectively, and these values are mainly attributed to the soluble phenolic compounds. Furthermore, AOXA by the DPPH\({}^{\bullet}\) method shows that catechin-3-O-gallate and gallocatedchin, both present in manney, had an IC\({}_{50}\) = 19.0 and 20.7 \(\mu\)M, respectively [48; 63]. AOXA of a cai pulp has been reported as 5795 and 93,682 \(\mu\)M Trolox/100 g dw according to the ABTS\({}^{\bullet}\) and DPPH\({}^{\bullet}\) assays, respectively. Fruit ripening has been shown to directly influence AOXA of a cai, where AOXA of unripe (green), intermediate maturity (reddish-brown) and ripe (dark purple) has been reported as 17.0, 4.04 and 2.78 \(\mu\)M TE/100 g dw, respectively [35]. DPPH\({}^{\bullet}\) radical scavenging capacity of passion fruit shows that seed extracts had the lowest IC\({}_{50}\) value (49.71 \(\mu\)g/mL), indicating a stronger AOXA than in the peel and pulp, which had values of 347.6 and 869.05 \(\mu\)g/mL, respectively. According to the ferric reducing