Variability in proximate composition, phytochemical traits and antioxidant properties of Iranian agro-ecotypic populations of fenugreek (Trigonella foenum-graecum L.)

Abstract

Fenugreek (Trigonella foenum-graecum L.) is a multi-use annual forage legume crop that is widely used in food products such as syrup, bitter run, curries, stew, and flavoring. In the present study, morphological traits, proximate composition (moisture, crude fibre, protein, fat, carbohydrate, and energy value), total phenol and total flavonoid contents, and antioxidant properties of 31 Iranian agro-ecotypic populations of the plant was investigated. Among the leaf and seed samples studied, the seeds exhibited the high ash (3.94 ± 0.12%), fat (7.94 ± 0.78%), crude fibre (10.3 ± 0.25%), protein (35.41 ± 1.86%), and carbohydrate (50.5 ± 1.90%) content. In general, more energy value (kcal/100 g) was also obtained from the seed (318.88 ± 1.78–350.44 ± 1.27) than leaf samples (45.50 ± 1.32–89.28 ± 0.85). Antioxidant activity and power of leaf samples were ranged from 67.95 ± 0.05‒157.52 ± 0.20 μg/ml and from 45.17 ± 0.01‒361.92 ± 0.78 μmol Fe+2 per g dry weigh, respectively. Positive linear correlations between antioxidant activity and total phenolic compounds were observed. A significant correlation between proximate composition (dependent variable) and some morphological features (independent variable) was observed. Considerable variability in the studied traits among the plant samples can be interestingly used in further food and production systems.