Nutritional, Antioxidant and Antibacterial Properties of Tirmania nivea, A Wild Edible Desert Truffle from Tunisia Arid Zone

Abstract

Nutritional composition, antioxidant and antibacterial properties of Tirmania nivea, a desert truffle largely distributed in Southern Tunisia, were evaluated. Carbohydrates were the most abundant macronutrients (57.83 g/100 g DM) followed by proteins (28.81 g/100 g DM) in T. nivea truffle. The ash content was 5.06 g/100 g DM, and potassium, calcium, phosphorus, magnesium and iron were found to be particularly abundant. The results of ascorbic acid, total carotenoids and total anthocyanins expressed on a dry mass truffle were 10.63 mg/100 g, 1.17 mg/100 g and 29.1 mg/100 g, respectively. Organic extracts of T. nivea contained relatively important amounts of total phenolics and flavonoids. The methanolic extract displayed the highest DPPH• radical-scavenging activity (IC50: 0.26 mg/ml) and lipid peroxidation inhibitory activity (IC50: 0.51 mg/ml), and also exhibited remarkable inhibitory activity against seven species of bacteria whose minimum inhibitory concentration values ranged from 0.36 to 1.32 mg/ml.