Aspergillus niger has shown production of metal chelating compounds mainly oxalic acid and citric acid. Production of oxalic acid by Aspergillus niger was found maximum in presence of Pb, followed by Cu+Pb and Cu. With increase in concentration of Pb to 50, 100 and 250 mg/L, the production of oxalic acid was increased. Whereas increase in concentration of Cu+Pb and Cu, resulted in decreased pro...

Although heavy metal ions are known to be toxic to the central nervous system (CNS), the mechanisms by which the CNS may protect itself from initial challenges of such toxic ions is unknown. The choroid plexus is the principal site of formation of the cerebrospinal fluid (CSF) which bathes the brain. We have determined in rats and rabbits that after intraperitoneal administration of lead, cadmi...

Heavy metals are metallic elements which have a high atomic weight and a density much greater (at least 5 times) than water. There are more than 20 heavy metals, but four are of particular concern to human health: lead (Pb), cadmium (Cd), mercury (Hg) and inorganic arsenic (As). According to the US Agency for Toxic Substances and Disease Registry, these four heavy metals are four of the top six...

Unprecedented bioaccumulation and biomagnification of heavy metals (HMs) in the environment have become a dilemma for all living organisms including plants. HMs at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to excessive augmentation of reactive oxygen species (ROS). This would inflict serious morphological, met...

Resistance nodulation cell division (RND)-based efflux complexes mediate multidrug and heavy-metal resistance in many Gram-negative bacteria. Efflux of toxic compounds is driven by membrane proton/substrate antiporters (RND protein) in the plasma membrane, linked by a membrane fusion protein (MFP) to an outer-membrane protein. The three-component complex forms an efflux system that spans the en...

Heavy metal compounds have toxic and medicinal potential through capacity to form strong specific bonds with macromolecules, and the interaction of platinum drugs at the major groove nitrogen atom of guanine bases primarily underlies their therapeutic activity. By crystallographic analysis of transition metal-and in particular platinum compound-DNA site selectivity in the nucleosome core, we es...

The heavy metals concentrations including Zinc, Copper, Lead and Cadmium (Zn, Cu, Pb and Cd) in water and sediments in Gorgan Bay and their accumulation in Rutilus frisii kutum, Acipenser persicus, Rutilus rutilus caspicus and Cyprinus carpio organs (gills, muscle, kidney and liver) were investigated. There was substantial increase in concentration of heavy m...

The heavy metals concentrations including Zinc, Copper, Lead and Cadmium (Zn, Cu, Pb and Cd) in water and sediments in Gorgan Bay and their accumulation in Rutilus frisii kutum, Acipenser persicus, Rutilus rutilus caspicus and Cyprinus carpio organs (gills, muscle, kidney and liver) were investigated. There was substantial increase in concentration of heavy m...

Heavy metal pollution by natural factors is a world-wide phenomenon. Release of large quantities of heavy metals without handling proper processes that could decrease the concentration of such a material is a hassle that makes strains resistant to these heavy metals apart from entering into human food chain. In this research, wastewater of four firms in Guilan province such as Foolad, Risandegi...

abstract with increasing population, mine activities for metal proceeding are also increasing, so environment will be influenced by contaminant especially heavy metals. in situ immobilization of heavy metals using inexpensive amendments is considered as a simple and cost-effective approach for reducing heavy metal contamination. in this research we used sequential extraction for assessing reduc...