Abstract
Methanol extracts of Opuntia ficus indica seeds and peels were fractionated and their subfractions were studied by high performance liquid chromatography (HPLC)-ultraviolet detection-atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS) for the first time. Eleven flavonoids are identified in the methanol peels extract. Flavonic aglycones belong to flavonols, dihydroflavonols and flavanones. The major glycosylated flavonoids are isorhamnetin mono-, di- and tri-glucosides. Four flavonoids were identified in the seeds extract as prenyl flavanones and methoylated flavones. Aglycones and monoglucosides were the major compounds of these extracts. Sugars were identified after extracts acid hydrolysis by comparison with standards.
The antioxidant activities of both methanolic extracts were determined with DPPH assay, ABTS test and reducing power. All methods showed the seeds extract is a powerful scavenger.