Abstract
This paper presents the results of in situ studies on solubilization of different phosphorus-bearing raw materials by application of natural ability to produce organic acids by Bacillus megaterium. Poultry bones as well as fish bones were used as renewable sources of phosphates. Morocco phosphorite was used as nonrenewable sources of phosphates. Glass columns, filled with the soil mixed with different doses (1, 5, and 10%) of mentioned sources of phosphorus, were used as a medium for solubilization. It was found that the amount of released phosphorus (determined in the eluent and expressed as P(2)O(5)) significantly increased in the cases of columns where B. megaterium was used, when compared with the control group (without microflora). Higher doses of phosphorus-bearing material used in the experiment influenced in the release of higher amount of phosphorus. The highest effectiveness of solubilization was found in the case of poultry bones. The experiment was repeated for poultry bones but with the supplementation of nutrients. It was found that the delivery of nutrients had a strong effect on the increase of effectiveness of solubilization. Two times higher amount of phosphorus (express as P(2)O(5)) was released from the hydroxyapatite structure of bones. It was confirmed that poultry bones could serve as a source of phosphates in microbial solubilization performed in in situ.