Indirect UO2 oxidation by Mn(II)-oxidizing spores of Bacillus sp. strain SG-1 and the effect of U and Mn concentrations.

Manganese oxides are widespread in the environment and their surface reactivity has the potential to modifythe geochemical behavior of uranium. We have investigated the effect of different concentrations of U and Mn on the coupled biogeochemical oxidation-reduction reactions of U and Mn. Experiments conducted in the presence of Mn(II)-oxidizing spores from Bacillus sp.

Energy levels of Penaeus indicus postlarvae on exposure to lead.

In the present investigation the changes in energy levels or caloric concentrations of Penaeus indicus postlarvae (PL) were determined after exposure to acute and sublethal concen- trations of lead. The biochemical constituents such as carbo- hydrates, proteins, and lipids were estimated in PL exposed to LC(5) (0.1495), LC(10) (0.

Acute toxicity of lead on tolerance, oxygen consumption, ammonia-N excretion, and metal accumulation in Penaeus indicus postlarvae.

The estuaries and backwaters that are the potential breeding grounds of penaeid shrimps are subject to heavy metal pollution through industrial effluents and domestic sewage. In the present investigation, laboratory experiments were conducted to study the acute toxicity of lead on tolerance, oxygen consumption, ammonia-N excretion, and metal accumulation in Penaeus indicus postlarvae. Static bioassay tests were employed to determine tolerance limits.