Optimization of biological phosphorus removal from contaminated sediments with phosphate-solubilizing microorganisms.
This study focused on the characteristics of phosphate-solubilizing microorganisms (PSMs) which can be applied for the removal of phosphorus from sediments to prevent eutrophication of lakes or ponds. A PSM isolated from rhizospheric soil and temporarily identified as Burkholderia glathei (MB 14) produced gluconate and acetate using glucose as a carbon source and its metabolic activity caused the pH of the liquid medium to decrease as low as 4.4. The molar ratio of solubilized PO4(3-)-P to total organic acids, gluconate and acetate, in the liquid medium was 1:2, which was lower than the theoretical molar ratio of 1:3 using Ca3(PO4)2 as a model phosphorus compound. In addition, biological PO4(3-)-P solubilization with MB 14 was more efficient than the direct addition of equivalent acid to the liquid medium. These results indirectly suggest that organic acids chelate Ca2+ during solubilization of PO4(3-)-P. The growth conditions for MB 14 that produced the maximum PO4(3-)-P solubilization were carbon sources of 8 g/l of glucose and 2 g/l of sucrose, and 0.1 g/l of arginine as a nitrogen source under an anoxic environment. The PSM species, MB 14, grown under these conditions was applied to treat contaminated dredged sediments in a bioslurry reactor. In 9 d, MB 14 solubilized 34.5% of total phosphorus in the contaminated dredged sediments.
Kim
Yong-Hak
YH
Department of Civil Engineering, Yonsei University, 134 Sinchon, Seodaemun, Seoul 120-749, Korea.
Bae
Bumhan
B
Choung
Youn-Kyoo
YK
D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D019117:Burkholderia / Q000378:metabolism*; D018929:Cell Culture Techniques / Q000379:methods; D019015:Geologic Sediments / Q000382:microbiology*; D010710:Phosphates / Q000378:metabolism*; D017553:Phosphorus Compounds / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D012995:Solubility; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
D010710:Phosphates; D017553:Phosphorus Compounds; D012722:Sewage; D014874:Water Pollutants, Chemical