Integrated geospatial-environmental metabolomics framework for human health risks and bioactive potential assessment in Hippophae rhamnoides L․
Abstract
Hippophae rhamnoides , is an important high-altitude, widely utilized medicinal and edible plant across Hindu Kush, Karakoram, and Himalayan (HKH) regions. However, unified information focusing on heavy metal contamination, human health risks, ecological drivers and metabolomic responses remains limited. Hence, present study applied a novel geospatial-environmental metabolomics framework to simultaneously evaluate dietary health risk associated with heavy metal accumulation, and bioactive potential in the edible parts of H. rhamnoides collected from 20 ecologically diverse locations in the HKH region of northern Pakistan. Estimated daily intake (EDI), health risk index (HRI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TCR) were determined for Cd, Cr, Cu, Ni, Pb, and Zn. Whereas bioactive potential was assessed through determination of total phenolic content (TPC), total flavonoid content (TFC), and antioxidant assays (DPPH, phosphomolybdate and FRAP) using standard analytical procedures. Remarkable heterogeneity was observed in heavy metal accumulation with maximum concentrations of Zn in south-eastern areas, while Cd, Cr, Cu, Ni and Pb were predominant toward north-western parts of HKH. Despite localized enrichment, estimated levels of THQ and HI for all metals remained below the USEPA safety limit (< 1), while cumulative target cancer risk for Cd, Cr and Pb were within permissible limits (ΣTCR ≈ 9.48 × 10⁻⁷ for ΣTCR ≈ 3.32 × 10⁻⁶ for adults and children, respectively). Bioactive profiling exhibited substantial variability, with higher average concentrations of metabolites in leaves compared to fruits, with elevated TPC reaching 328.77 ± 4.83 mg GAE/100g DW, and TFC 102.57 ± 21.00 mg QE/100 g DW in samples collected from Hunza region. However, fruits collected from Skardu, Astor and Ghizer localities depicted significant antioxidant potential with > 90% DPPH free radical inhibition capacity. Multivariate environmental-metabolomic analyses confirmed that altitude, UV-index, temperature, wind speed, precipitation, soil organic matter and minerals substantially ( p < 0.05-0.01) regulate secondary metabolites biosynthesis and heavy metal uptake. Present study provides first integrated geospatial-environmental metabolomics framework for heavy metal contamination, human health risks, and antioxidant potential in H. rhamnoides along ecological gradients of HKH region. The findings signify H. rhamnoides as a safe and rich resource of natural antioxidants, emphasizing its potential application in functional foods and nutraceuticals, while validating the significance of geo-climatic landscapes in shaping pollutant dynamics and resilience of flora in high-altitude ecologies.