Genotypic and Environmental Effect on the Concentration of Phytochemical Contents of Lentil (Lens culinaris L.)

Abstract

The health-promoting effects of lentil seeds due to phenolic compounds and other antioxidants make lentils a potential source of functional food or feed ingredients. The objective of this study was to evaluate the effects of genotype and growing environment on the phytochemical contents and antioxidant activities such as ABTS (2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays of soluble extracts from five lentil cultivars grown in ten diverse locations over a 2-year experimental period. Total phenolic content (TPC), total flavonoid content (TFC), total proanthocyanidin content (TPAC), total hydrolyzed tannin content (TNC), tocopherols and carotenoids were investigated. The major proanthocyanidins and individual polyphenols were quantified by high-performance liquid chromatography. Our results indicated that flavanols were the main phenolic compounds in hydrophilic extracts, followed by phenolic acids. Concerning lipophilic extracts, tocopherols and carotenoids were the main components, with γ-tocopherol and lutein being the predominant isomers, respectively. In general, both genetic and environmental effects had a strong impact on all bioactive components tested. Greater variation due to environmental effects was found for phenolic compounds (TPC, TFC and TPAC) and antioxidant activities; however, tocopherols and carotenoids revealed a high genotypic dependence. The principal component analysis highlighted the genotypes with higher content of antioxidants and stability across environments. The red lentil population “03-24L” was characterized as a promising genetic material due to its high phenolic contents and antioxidant capacity values across environments and is suggested for further investigation. In conclusion, multi-environmental trials are essential for a better understanding of the genotypic and environmental effect on phytochemical profiles of lentils and provide important information for breeding or cultivating lentil varieties of high-bioactive value.