Abstract
The objective of this study was to investigate the in vitro antioxidant activities of polyphenolic extract of Terminalia chebula
Retzius (Combretaceae) fruits. The polyphenolic extract of T. chebula fruits was evaluated for antioxidant activity by determining
the reducing power, total antioxidant capacity, DPPH radical concentration (IC50 14g/mL), nitric oxide radical concentration
(IC50 30.51g/mL) and hydrogen peroxide scavenging activity (IC50 265.53 g/mL) under in vitro conditions. Moreover, the
phytochemical characterisation of the extract was also measured by determining the total phenolic, flavonoid, tannin and ascorbic
acid contents. Characterisation of the extract was also performed by HPLC profiling with the standard gallic acid. The present study
demonstrated that the extract has significant reducing capacity and nitric oxide scavenging activity. It also scavenges hydrogen
peroxide-induced radicals. The activity of the extract may be due to the total polyphenolic content. The antioxidant activity of the
extract is significantly higher than the standard ascorbic acid, and its activity is concentration-dependent. It is concluded that a
polyphenolic-rich fraction of T. chebula fruits is a potential source of natural antioxidants.
© 2014 The Authors. Production and hosting by Elsevier B.V. on behalf of Taibah University. This is an open access article under
the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
Keywords: Terminalia chebula; Ascorbic acid; Total antioxidative capacity; DPPH radical scavenging activity; Nitric oxide radical scavenging
assay; Hydrogen peroxide scavenging assay
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