Antioxidant Potential and Characterization of Polyphenol Compounds in Moringa oleifera Pods

The aim of this investigation was to comparatively assess the antioxidant and polyphenol compounds in fresh moringa pods sourced from two different regions in Australia, namely Queensland (QLD) and Western Australia (WAU). Total polyphenol content varied between 1.64 and 5.97 mg GAE/g in moringa pod samples from QLD, while it ranged from 2.84 to 4.31 mg GAE/g in WAU samples. Total flavonoid content in QLD and WAU samples averaged 4.62 and 4.24 mg QE/g, respectively. Total condensed tannin content in QLD and WAU samples averaged 2.07 and 1.60 mg CE/g, respectively. The QLD samples had higher DPPH (2.87 vs. 2.74 mg AAE/g), ABTS (15.0 vs. 12.9 mg AAE/g), and total antioxidant capacity (2.34 vs. 1.46 mg AAE/g) than WAU samples. LC-ESI-QTOF-MS/MS analysis identified 111 polyphenol compounds in moringa pod samples, including phenolic acids, flavonoids, and tannins. Some compounds were prevalent across most samples, such as 3-sinapoylquinic acid and theaflavin. The study revealed that moringa pods contain a high concentration of polyphenols with strong antioxidant capacity. These findings highlight the substantial influence of regional effects on the polyphenol content and bioactive properties of moringa pods.