Free radical scavenging activity and HPLC-MS identification of major anthocyanin in ripe <i>Ziziphus mucronata</i> fruit collected in Burkina Faso

Abstract

In recent decades, interest in anthocyanin pigments has increased due to their possible use as natural food colorants, antioxidants, and  anti-inflammatory agents. This study aimed to identify the major anthocyanins in ripe Ziziphus mucronata fruit harvested in the  Niangoloko classified forest. HPLC-ESI-MS/MS was used to identify anthocyanins. The total phenolic content (TPC) and total flavonoids  (TFC) were assessed using the Folin-Ciocalteu reagent and the spectrophotometric method of Khan (2012) respectively. Total anthocyanin content (TAC) was obtained using a differential pH method. Total antioxidant potential (TAC) was carried out using DPPH and ABTS tests.  Cyanidin 3-O-glucoside and cyanidin 3-O-galactoside were major anthocyanins identified by HPLC-MS. Quantitative analysis showed that  this fruit contains an average of 321 ± 11 mg gallic acid equivalent (GAE), 3815 ± 15 mg quercetin equivalent (QE), and 9.64 ± 0.70 mg  cyanidin 3-O-glucoside equivalent per 100 g fresh fruit. Total antioxidant contents ranged between 206.57 ± 7.00 and 88.72 ± 0.87 mg TE/100 g fresh fruit. Free radical scavenging activity of Ziziphus mucronata fruit was found to be 342.90 µg/mL, while that of standard  Trolox was 21.8 µg/mL. Therefore, Ziziphus mucronata fruit could be a potential source of natural bioactive substances of great interest  to consumers.