In situ solubilization of phosphorus‐bearing raw materials by Bacillus megaterium

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.

Phosphorus Microbial Solubilization as a Key for Phosphorus Recycling in Agriculture

“…In this case, the enhanced growth of bacterial cells would produce more acids or enzymes that would solubilize the phosphorus from ashes. Figure 3 shows the stages in the production of phosphorus biofertilizers [35][36][37][38][39][40][41][42][43][44][45][46][47][48].…”

“…Parameters that express and characterize the solubilization are used to evaluate the effectiveness and are as follows: pH, μ (day −1 ), and CP 2 O 5 . To describe experimental data, a few models were evaluated to understand the changes in the process [43][44][45].…”

“…C max (mg/L) are constants describing the decay of curve. Evaluated value of L can be interpreted as value of pH that corresponds with the half of phosphorus (expressed as P 2 O 5 ) that under considered condition could be released/solubilized [43].…”

Valorization of Phosphorus Secondary Raw Materials by Acidithiobacillus ferrooxidans

“…A wider application of biotechnologies to activate phosphate raw materials may help reduce the adverse phenomena attendant on the manufacturing of conventional fertilizers [ 3 ]. These processes can involve bacteria and fungi that solubilize phosphate (Phosphate Solubilizing Bacteria—PSB, Phosphate Solubilizing Fungi—PSF) [ 4 ].…”

“…In this type of fertilizer, phosphorus can be obtained from different, mostly poor raw materials, such as wastes from the agro-food industry, sludge, etc. [ 3 , 11 ]. In the case of the latter, the solubilization of phosphorus compounds occurs after the application of the fertilizer to the soil environment.…”