Antioxidant activities, phenolic compounds, and mineral composition of seed from Acacia retinodes, A. provincialis and A. tenuissima

[Display omitted] •Acacia seeds were relatively high in potassium, sodium, iron, and copper.•There were more free polyphenols present compared to bound polyphenols.•Mineral composition and antioxidant activities vary between different seed batches.•The predominant phenolic compound found was 6-Hydroxy-2-methylindole. Seeds of the species Acacia retinodes, A. provincialis, and A. tenuissima) from different growing locations were analysed for their mineral composition, free and bound polyphenols, and flavonoids. Previous research has studied these compounds in only a limited number of Acacia species, and only one study reports significant differences between three species. All species were rich in potassium (353 – 427 mg/100 g), sodium (14 – 240 mg/100 g) and iron (7 – 8 mg/100 g). The free polyphenol extracts of all species had higher total phenolic content, total flavonoid content and antioxidant activities than their bound counterparts, indicating the possibility of higher bioavailability than the bound polyphenol extracts. The predominant phenolic compounds found in the Acacia polyphenol seed extracts were 6-Hydroxy-2-methylindole and 2,2′-Methylenebis(6-tert-butyl-methylphenol), though no phenolic compounds were identified in the bound extracts of A. retinodes Grampians and A. provincialis Tarrington. Other compounds identified in the seed extracts include sucrose, d-fructofuranose and d-pinitol.