Assessment of Macro-Mineral Bioavailability in Medicinal Plants and Corresponding Soils of Punjab, Pakistan: Implications for Human Health and Daily Intake

Abstract

This study investigated the concentrations of essential macrominerals, sodium (Na), calcium (Ca), potassium (K), and magnesium (Mg), in soils and six medicinal plants collected from two distinct locations in Punjab, Pakistan. Significant site-wide variations in mineral uptake and soil availability were recorded via ANOVA, with fluctuating trends observed across locations and species. The sodium concentrations in soils (59.09-59.77 mg/kg) and plants (0.026-0.61%) were below critical levels, indicating a potential deficiency that may affect both plant productivity and dietary sufficiency. Notably, Peganum harmala presented the greatest accumulation of Na, whereas Withania somnifera presented the lowest accumulation. The calcium content ranged from 72.90-84.51 mg/kg in soils and 0.191-0.391% in plants, with Solanum nigrum showing the highest uptake. Despite being above the critical soil level (71 mg/kg), the plant Ca concentrations were insufficient to meet the recommended daily intake (350–1100 mg/day). The potassium levels in the soils ranged from 68.53--83.73 mg/kg, and those in the plants ranged from 0.59-1.15%, yet most values were below the 0.8% critical threshold, indicating K deficiency. The bioaccumulation factor (BCF) for K was remarkably high (127.03-155.52), suggesting metal sensitivity in certain species, such as Adhatoda vasica. The magnesium level remained consistently below the soil critical value of 9.10 mg/kg, whereas the plant Mg content ranged from 0.093-0.196%, approaching or slightly exceeding the 0.1% threshold. The calculated daily intakes from plant consumption revealed insufficient contributions of Na and K but relatively adequate Mg, supporting its therapeutic relevance. Correlation analysis revealed weak or nonsignificant relationships between the soil and plant mineral contents, indicating metal-specific uptake mechanisms and possible antagonistic interactions. These findings underscore the need for soil amendment strategies and the informed use of medicinal herbs in dietary formulations to ensure adequate macromineral intake.

Keywords::   Macro-Minerals, Medicinal Plants, Human Health, Kallar Kahar, Soil, Bioconcentration Factor