Traditional medicinal plants are widely used for therapeutic, nutritional, and cosmetic applications, yet their safety and quality remain major concerns due to possible contamination and processing related degradation. This study evaluates the physicochemical properties, antioxidant activity, and heavy metal-associated health risks of nine medicinal plant species commonly used in Bangladesh-ILCR, Phyllanthus emblica, Withania somnifera (leaf and root), Terminalia arjuna, Justicia adhatoda, Ocimum sanctum Linn., Hibiscus rosa-sinensis, Psidium guajava Linn., and Azadirachta indica processed through heat pump and traditional sun drying methods. Moisture, protein, and total phenolic contents were determined alongside DPPH radical scavenging activity to assess bioactive compound preservation. Heavy metal concentrations (Pb, Cd, Cr, Mn, As, Ni, and Se) were quantified via Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS), and non-carcinogenic (HQ, HI) and carcinogenic (ILCR) health risks were estimated following USEPA guidelines. Results revealed that heat pump drying significantly enhanced protein and phenolic retention while reducing residual moisture compared to sun drying. DPPH assays confirmed superior antioxidant activity (up to 88% scavenging at 200 µg/mL) in heat pump dried samples. Heavy metal concentrations in all samples were below permissible limits, with HQ, HI, and ILCR values indicating negligible non-carcinogenic and carcinogenic risks. Heat pump drying demonstrated enhanced preservation efficiency of nutritional and bioactive components while minimizing contamination risks. These findings provide strong scientific evidence supporting the adoption of controlled heat pump drying for safer, higher-quality, and more efficacious herbal product development in Bangladesh and beyond.
Sadia Afrin, Abdullah Al Mamun, Hayatullah et al.· Discover Chemistry· 0 citations
Subsurface geology in deltaic floodplains is highly heterogeneous, strongly influencing groundwater development. In response to growing groundwater stress and the need for potential management, this study investigates the capability of vertical electrical sounding (VES) to characterize lithological variability and infer hydrostratigraphic conditions within the active floodplain of the Quaternary deposits of Jashore, Bangladesh. A total of 18 VES surveys were conducted using the Schlumberger array with investigation depths of 90–150 m. One-dimensional inversion modeling using IX1D was validated against nearby borehole logs, showing strong agreement for layer depth and thickness (R² > 0.95) and approximately 75% agreement in lithological classification. The results show five geoelectric layers with resistivity values ranging from 6 to 60 Ωm, corresponding to topsoil, clay, silty clay, and sandy lithologies, indicating considerable lateral and vertical heterogeneity across the floodplain. Furthermore, geo-electric cross-sections indicate that shallow or thick sandy units are concentrated around VES-3–7, 9–11, and 14–17, whereas clay-rich deposits dominate VES-1, 12, 13, and 18. In particular, the sandy layers characterized by relatively high resistivity (36–60 Ωm) and substantial thickness (32.35–94 m) are interpreted as potential aquifer zones, while the overlying clay and silty clay units suggest as confining to semi-confining layers. Moreover, the absence of very low resistivity signatures suggests limited saline water intrusion within the investigated depth range. Although hydrochemical and pumping-test data are still required for confirmation, our study develops a conceptual framework of lithological heterogeneity using VES for potential groundwater management applicable for similar floodplain environments.
Md. Imam Sohel Hossain, Md. Moklesur Rahman, M. Mostafa et al.· Discover Geoscience· 0 citations
