Removal of cadmium by bioflocculant produced by Stenotrophomonas maltophilia using phenol-containing wastewater.
Bioflocculants have been applied in numerous applications including heavy metals removal. A major bottleneck for commercial application of bioflocculant is its high production cost. Phenol-containing wastewater are abundantly available. However, the toxic phenol inhibited the microbial activities in the subsequent fermentation processes. Consequently, strains that can secrete phenol-degrading enzymes and simultaneously produce bioflocculants through directly degrading the phenol are of academic and practical interests. A phenol-degrading strain, Stenotrophomonas maltophilia ZZC-06, which can produce the bioflocculant MBF-06 using phenol-containing wastewater, was isolated in this study. The effects of culture conditions including initial pH, dissolved oxygen, phenol concentration, inoculum size, and temperature on MBF-06 production were analyzed. The experimental results showed that over 90% flocculating activity was achieved when the phenol was used as a carbon source and 4.99 g/L of MBF-06 was achieved under the optimized condition: 2.0% dissolved oxygen, 800 mg/L phenol concentration, 10% inoculum size, an initial pH of 6.0, and a temperature of 30 °C. The bioflocculant MBF-06 contained 71.2% polysaccharides and 27.9% proteins. The feasibility of cadmium removal using MBF-06 was evaluated. The highest flocculating efficiency for cadmium was 81.43%. This study shows for the first time that Stenotrophomonas maltophilia ZZC-06 can directly convert phenol into a bioflocculant, which can be used to effectively remove cadmium.
School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China.
Honggao
H
Chen
Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients, Chemistry and Biology Science College, Hubei University of Education, Wuhan 430205, China.
Chunying
C
Zhong
College of Agriculture and Life Sciences, Texas A&M University, College Station, TX 77843, USA.
Hudson
H
Berkhouse
Department of Political Science, Texas A&M University, College Station 77843, USA.
Youlang
Y
Zhang
School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China.
Yao
Y
Lv
School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China.
Wanyu
W
Lu
College of Economics and Management, Nanjing Agricultural University, Nanjing 210095, China.
Yongbing
Y
Yang
School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China. Electronic address: wallice24@hotmail.com.
Jiangang
J
Zhou
D002104:Cadmium / Q000737:chemistry*; D002244:Carbon / Q000378:metabolism; D011232:Chemical Precipitation; D005285:Fermentation; D005427:Flocculation; D006863:Hydrogen-Ion Concentration; D010100:Oxygen; D019800:Phenol / Q000737:chemistry*; D010636:Phenols; D020615:Stenotrophomonas maltophilia / Q000378:metabolism*; D013696:Temperature; D062065:Wastewater / Q000737:chemistry*
D002104:Cadmium; D002244:Carbon; D010100:Oxygen; D019800:Phenol; D010636:Phenols; D062065:Wastewater
Bioflocculant; Cadmium removal; Phenol; Stenotrophomonas maltophilia; Wastewater treatment