Role of Acinetobacter spp. in Solid-Liquid Separation in Activated Sludge Process
Thirty-five bacterial strains isolated from sewage activated sludge were tested by a spectrophotometric assay for their ability to coaggregate in two-membered systems. Of these, Acinetobacter johnsonii S35 coaggregated well with sixteen strains to different degrees as indicated by aggregation index (AI)=ca. 70 to 99%. The coaggregating partner strains were identified by sequencing of 16S rRNA genes as Bacillus cereus, Blastomonas natatoria, Microbacterium esteraromaticum, Mycobacterium sp., Oligotropha carboxidovorans, Thermomonas brevis, Xanthomonas axonopodis, and Enterobacteriaceae family. Acinetobacter junii S33 coaggregated with 8 strains, which were also coaggregating partners of A. johnsonii S35, as indicated by AI=ca. 60-93%. Addition of 2 mM EDTA inhibited coaggregation in all combinations of A. johnsonii S35 and its partner strains. In addition, addition of simple sugars such as glucose, galactose, mannose and rhamnose partially inhibited coaggregation. Periodate treatment of A. johnsonii S35 or Actinase E treatment of B. cereus, M. esteraromaticum, T. brevis, and Enterobacteriaceae family inhibited their coaggregation, indicating that lectin-saccharide interaction may be involved in the coaggregation between these sludge bacteria. The population of Acinetobacter spp. in sewage treatment plant was 3-7% and its role in bioflocculation is discussed. The present study revealed that Acinetobacter spp. play an important role in solid-liquid separation in activated sludge process.
coaggregation Acinetobacter johnsonii Acinetobacter junii solid-liquid separation sludge bacteria activated sludge
Kimchhayarasy PHUONG Kazuo KAKII Toshiyuki NIKATA
Department of Material Science and Engineering,Graduate School of Engineering,Utsunomiya University, Department of Material Science and Engineering,Graduate School of Engineering,Utsunomiya University,
国际会议
2009 International Symposium on Environmental Science and Technology(2009环境科学与技术国际会议)
上海
英文
2052-2059
2009-06-02（万方平台首次上网日期，不代表论文的发表时间）