Fennel Pignut tubers: A source of nutritional and phenolic compounds with antioxidant and in vivo anti-inflammatory activity

Abstract

Bunium ferulaceum Sm. is an economically important plant valued for its culinary and medicinal applications. However, no information exists about the nutritional composition, bioactive compounds, antioxidant potential, and anti-inflammatory activity of B. ferulaceum tubers and its potential for use in food and medicinal applications. The tubers were found to be composed of carbohydrates (78%), proteins (9%), and lipids (1%). Carbohydrates tubers were primarily composed of glucose (81%), with starch accounting for 71 % and total dietary fiber accounting for 17%. Linoleic acid was the dominant unsaturated fatty acid in triacylglycerides and potassium and iron were the main minerals. The hydromethanolic extract contained notable amounts of polyphenols (95 mg GAE/100 g d.w). It exhibited good DPPH· radical scavenging ability (IC50 = 383 μg/mL), a total antioxidant capacity of 144 μg AAE/mg extract, and a β-carotene bleaching inhibition of 57%. Mice fed with the tuber’s powder and their extract showed a significant reduction in acute inflammation in xylene-induced ear edema reaching 45% at 2.5 g/kg b.w for the tuber’s powder and 52% at 600 mg/kg b.w for the extract. Moreover, mice treated with a single oral dose (2.0 g/kg b.w) of the extract showed no signs of toxicity. The increased activity of the tuber’s extract may be linked to phenolic compounds like catechin and 5- O -caffeoylquinic acid. This study highlights the well-balanced nutritional profile of fennel pignut tubers, particularly their soluble glucans, and their polar extracts’ functional activities, supporting their potential in food and medicinal applications. • B. ferulaceum tubers are nutrient-rich and contain essential minerals • Catechin, 5- O -caffeoylquinic, and organic acids dominate the hydromethanolic extract • B. ferulaceum tubers and their extract have marked anti-inflammatory activity • The hydromethanolic extract showed no toxicity even at high dose