Antioxidant; Coconut water; Drosophila melanogaster; Free radicals; Phenolic compound

Abstract
Coconut water (CW) has gained wide attraction as a known functional food that offers additional benefits to its basic nutritional value. CW is employed in the management of oxidative stress-associated diseases for its natural antioxidant features. This study sought to investigate CW antioxidant capacity and effect upon its dietary inclusion in an Alcl3-induced amnesic Drosophila melanogaster. CW was extracted from the coconut fruit cotyledon and supplemented in the flies’ diet for five days. The CW extract antioxidant activity was examined in vitro through the total phenol, total flavonoid content, ferric reducing power, iron-chelating ability, ABTS* and DPPH* scavenging ability assays. Likewise, the anti-lipid peroxidation potential of CW extract was also measured in vivo using D. melanogaster. The CW extract has a total phenol content of 1.48 ± 0.43 (mg/g GAE) and a total flavonoid content of 0.53 ± 0.02 (mg/g QE) which could be attributed to its scavenging ability against ABTS* and DPPH* in vitro with an increase in extract concentration. Similarly, a positive trend was detected in the ferric reducing antioxidant power and iron-chelating ability tests. Furthermore, dietary inclusion of CW in groups fed with 0.1% and 1% CW lowers Malondialdehyde (MDA) concentration significantly (p < 0.01 and p < 0.0001 respectively) in Alcl3 induced flies. This correlates with CW’s ability to considerably (p < 0.05) reduced MDA in vitro in a concentration-dependent manner (0.01 – 0.03 mg/mL). These findings provide substantial information that affirms CW's natural antioxidant ability, thus bolstering its therapeutics usage.