Effect of cold arid high-altitude environment on bioactive phytochemical compounds of organically grown Brassicaceae vegetables for nutri-health security in mountainous regions

High-altitude (HA) environment presents immense physiological adversities for humans that have been overcome by supplementing bio-active phytochemicals from functional foods that support and accelerate acclimatization under these extreme environmental conditions. Several agricultural interventions have been investigated to enhance the phytochemical content in vegetables however; these studies have been limited to low-altitude (LA) regions only. In view of an existing knowledge gap, current work is designed to compare the phytochemical compositions of HA and LA-grown Brassicaceae vegetables (cabbage, cauliflower, knol-khol, and radish) using organic treatments via farm yard manure (FYM) and Azotobacter. The open field study was conducted as a two-factorial randomized block design. The first factor was treatment (T₁-FYM, T₂-Azotobacter, T₃-FYM + Azotobacter, and T₄-control) while the second was locations (HA and LA). Among all these treatments, the application of treatment T₃ in HA-grown cabbage showed the highest total phenolic content (TPC; 9.56 μg/mg), total flavonoids content (TFC; 14.48 μg/mg), and antioxidant potential using 2,2-diphenyl-1-picrylhydrazyl (DPPH; 85.97%) and ferric reducing antioxidant power (FRAP; 30.77 μg/mg) compared to LA grown samples. Reverse Phase high performance liquid chromatography (RP-HPLC) analysis showed that treatment T₃ at HA led to significantly high kaempferol (0.92 μg/mg) and sulforaphane (8.94 μg/mg) contents in cabbage whereas, indole-3-carbinol (1.31 μg/mg) was higher in HA grown cauliflower. The present study provides scientific evidence for the enrichment of health-promoting phytochemical compounds in Brassicaceae vegetables grown with T₃ treatment specifically at HA.