Background: American persimmons (Diospyros virginiana L.) are known as a widespread cultivar which were traditionally used by Native Americans as a food source, and since ancient times have been used in folk medicine. The objective of this study was to evaluate the antioxidant activity and phenolic content of Diospyros virginiana genotypes.
Methods: The content of the total antioxidant activity and phenolic compounds from the fruits of the American persimmon (Diospyros virginiana L.) of six genotypes were compared. Antioxidant activity (AOA) was measured using three different photometric methods – DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) and FRAP (ferric-reducing antioxidant power). Total phenolic content (TPC) was evaluated using Folin-Ciocalteu reagent assay.
Results: The results for AOA (μMol Trolox/g) determined by the DPPH method varied from 51.68 (DV-05) to 100.87 (DV-03), those obtained by the ABTS method varied from 65.40 (DV-05) to 142.26 (DV-03), and those obtained by the FRAP method varied from 45.06 (DV-05) to 109.30 (DV-03). The results for TPC varied from 590.75 ±27.98 mg/100 g (DV-05) to 1325.12 ±77.30 mg/100 g (DV-03). The highest results for AOA and TPC were achieved for the fruits of genotypes DV-03 and DV-05. A positive linear correlation was found between antioxidant activity and total phenolic content in the examined plant material.
Conclusions: The results showed that all fruit extracts exhibited strong antioxidant activities, which generally correlated positively with the total phenolic content. This study demonstrates the potential of the fruits of Diospyros virginiana grown in Ukraine as a possible source of valuable polyphenol content, with high anti- oxidant activities and health-promoting properties. The high contents of phenolic compounds and significant linear correlation between the values of the concentration of phenolic compounds and antioxidant activity indicated that these compounds contributed to the strong antioxidant activity.
Keywords: American persimmon; antioxidant activity; fruit; phenolic compounds.