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
Abstract The marine environment harbours a rich diversity of microorganisms capable of producing bioactive compounds, including pigments with significant therapeutic potential. However, the exploration of bacterial pigments from marine bacteria, particularly from Cox’s Bazar region in Bangladesh, remains under-researched. This study investigated the antibacterial and cytotoxic properties of two yellow pigment-producing bacteria, Pseudomonas aeruginosa strain BDIFST240011 and Microbacterium hominis strain BDIFST240012, isolated from sediment samples of the Bay of Bengal. The microbial load was assessed, and the isolates were characterized morphologically, molecularly (16S rRNA sequencing), and biochemically to confirm their identities. Pigment production was optimized under various growth conditions, with Luria–Bertani medium supplemented with seawater providing optimal results. The pigments, pyocyanin from P. aeruginosa and pyoverdine from M. hominis, were characterized using UV-visible and Fourier Transform Infrared (FTIR) spectroscopy, confirming their chemical identities. Antibacterial activity was evaluated through agar well diffusion, revealing significant inhibition of Bacillus subtilis and other bacterial strains, with pyocyanin showing stronger efficacy. The cytotoxic effects of both pigments were assessed using the MTT assay, showing a dose-dependent reduction in Vero cell viability, with pyocyanin exhibiting more significant cytotoxicity. This research addresses the gap in marine bacterial pigment studies and highlights their potential for pharmaceutical applications. The findings suggest that marine-derived bacterial pigments can serve as a source of novel antibacterial agents and provide a foundation for future research into their clinical and industrial applications. Future studies should focus on elucidating the mechanisms of action and exploring the broader therapeutic uses of these pigments.
Ashrafunnesa Flora, Sadia Afrin, Mohammad Nazrul Islam Bhuiyan et al.· Journal of the Marine Biolog...· 0 citations
