Biodegradation of benzo[a]pyrene in soil by Mucor sp. SF06 and Bacillus sp. SB02 co-immobilized on vermiculite.
Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene (BaP). The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10-200 mg/kg. The scanning electronic microscope (SEM) analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.
Su
Dan
D
Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Li
Pei-jun
PJ
Frank
Stagnitti
S
Xiong
Xian-zhe
XZ
D000327:Adsorption; D000538:Aluminum Silicates; D001407:Bacillus / Q000378:metabolism* / Q000648:ultrastructure; D001564:Benzo(a)pyrene / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D009089:Mucor / Q000378:metabolism* / Q000648:ultrastructure; D012989:Soil Pollutants / Q000378:metabolism*
D000538:Aluminum Silicates; D012989:Soil Pollutants; C003760:vermiculite; D001564:Benzo(a)pyrene