Understanding the nutritional profile of Vigna trilobata: A lesser-known, underexplored grain legume

Abstract

Vigna trilobata (L.) Verdc. is a potential neo-domesticated legume species of section Aconitifoliae. The seeds are edible, and local communities often cultivate it primarily for pasture but occasionally as a food source. Vigna trilobata is native to Indian subcontinent and frequently distributed in the Southern part of India. In present study, we conducted an evaluation of the proximate composition and phytochemical analysis of Vigna trilobata. The proximate composition and mineral content were determined using AOAC methods. Additionally, we performed phytochemical analysis, antioxidant activity, GC-MS analysis, and FTIR profiling using the methanolic extract of seed powder. Our findings revealed that the seeds of Vigna trilobata are a rich source of crude proteins (17.51 g/100 g) compared to total carbohydrates and free amino acids. They also exhibited high levels of magnesium, followed by sulphur, potassium, sodium, and calcium content. The seed extracts showed elevated levels of total phenolic content (32.23 to 50.12 mg/GAE/100 g), total tannin content (24.91 to 32.15 mg/TTC/100 g), and total alkaloid content (24.66–27.28 mg/CoE/100 g), with relatively lower levels of total flavonoid content (20.83–23.17 mg/RE/100 g). The higher levels of total phenolic content and total tannin content correlated with increased antioxidant activity, as assessed by DPPH and phosphomolybdenum assays. FTIR profiling provided insights into the presence of various functional groups of chemical compounds, while Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed that the presence of diverse photochemical in seeds incudes Octanoic acid, Decanoic acid, Eicosanal etc. with with antibacterial and anti-inflammatory activity. The results obtained in our investigation provide valuable insights into the nutritional and phytochemical composition of Vigna trilobata seeds. This knowledge could be harnessed in the utilization of Vigna trilobata functional foods and in crop improvement programs aimed at enhancing the nutritional content and health-promoting properties.