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Microbial Ecology of Activated Sludge I. Dominant Bacteria

Applied microbiology 10/1964; 12(5):412-7.
Source: PubMed

ABSTRACT Over 300 bacterial strains were isolated from seven samples of activated sludge by plating on sewage agar. Gram-negative bacteria of the genera Zoogloea and Comamonas predominated. Many isolates (51%) showed sudanophilic inclusions of poly-beta-hydroxybutyric acid, whereas 34% accumulated iodophilic material on media containing starch. A large number required either vitamins or amino acids, or both, for growth. None of the isolates tested for their ability to bring about changes in autoclaved sewage produced an effluent comparable in quality to the activated sludge control, although the Zoogloea did produce activated sludgelike flocs. A study of 150 bacterial strains isolated from raw sewage revealed that they differed from the sludge isolates in several respects. Coliforms, which constitute nearly a quarter of the sewage isolates, were rarely encountered in sludge.

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    • "C. testosteroni is a Gram-negative aerobic bacteria that is found in diverse environments (Ma et al. 2009). Bacteria of the genus Comamonas are predominant in activated sewage sludge (Dias and Bhat 1964) and are defined by a poor ability to use carbohydrates; instead carbon is derived from molecules such as testosterone and other cyclic hydrocarbons (Linares et al. 2008; Horinouchi et al. 2010). C. testosteroni has recently been identified as an opportunistic human pathogen that has been found in various hospital infections including meningitis (Arda et al. 2003; Jin et al. 2008), bacteremia (Gul et al. 2007) and endophthalmitis (Reddy et al. 2009). "
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    Glycobiology 05/2011; 21(10):1331-40. DOI:10.1093/glycob/cwr072 · 3.14 Impact Factor
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    • "Successful integration of activated sludge as the biocomponent in an FM-BOD assay would overcome the timeconsuming and expensive requirement of culturing several strains of bacteria to produce a mixed consortia biocatalyst. Activated sludge also represents the ideal biocatalyst for the BOD 5 assay as it contains a diverse community of heterotrophs from a number of functional groups that will ensure a high proportion of biodegradation occurs (Dias and Bhat, 1964, 1965; Hiraishi et al., 1989). In addition, activated sludge can be readily sampled from most WWTPs and an activated sludge FM-BOD assay would be far more relevant to the wastewater industry, as measurements of the industrial effluent BODs, would be representative of the BOD loading exerted upon the plant activated sludge ultimately treating the same wastewater. "
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    Water Research 12/2010; 44(20):5981-8. DOI:10.1016/j.watres.2010.07.042 · 5.32 Impact Factor
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    • "William T. Stringfellow and Lisa Alvarez-Cohen 2538 activated sludge samples (Table 2). Perhaps a more realistic microbial model for activated sludge MLSS would consist of a mixture of Gram positive bacteria , such as Rhodococcus rhodochrous and Gram negative bacteria such as Pseudomonas stutzeri, as MLSS is typically composed of both Gram positive and Gram negative organisms (Dias and Bhat, 1964; Taber, 1976; Lemmer and Kroppenstedt, 1984). "
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