Bacillus Cereus Biodegradability of Phosphorus and other Heavy Metals in Nigeria’s Agbaja Iron Ore

An investigation into the capacity of Bacillus cereus to degrade some of the heavy metals found in Nigeria’s Agbaja iron ore was carried out in the laboratory for 10 weeks.  As obtained iron ore from Agbaja community in Kogi State of Nigeria was crushed and sieved to select 0.50/0.25mm particle size.  Bacillus cereus was one of the microorganisms identified after culturing a portion of the crushed iron ore in suitable media overtime.  Some control samples were also set up that did not contain either the microbes and/or ore samples.  At weekly interval, samples were removed and analyzed to obtain ammonium phospho-molybdate precipitate which was titrated with 0.1 N-HCl to determine the amount of phosphorus (P).  Liquid samples were analyzed for heavy metals concentration using UniCam Solaar 969 AA spectrophotometer.  Findings reveal that the microbes degraded 58.18% P and in the process accumulated some of the heavy metals: 82.17% Cu, 100% Cd and Fe, 8.12% Zn and 68.42% Pb.  The pH of the media remained entirely basic attaining 9.63 at the end of the investigation.  The log of microbial density which maximized in the 3rd week at 7.498 cfu/ml (colony forming unit/milliliter) showed serious decline by the 10th week to 4.763 cfu/ml.  It is possible the microorganisms may have had a low degradation capacity as a result of heavy metals over-accumulation, especially that of Pb, known to be highly poisonous above certain concentrations.  Recommendations include a further study of the broth media mixture with samples and microorganisms as findings may enhance an efficient metabolic wastes management and a sustainable microbial degradation of iron ore samples.