Microbial consortia

Novel aromatic carboxylation reactions have been observed in the anaerobic transformation of phenols to ben2oates (82). A mixed anaerobic microbial consortium apparentiy transforms phenol (33) through an intermediate to ben2oic acid (34) via dehydroxylation. This reaction has not yet been widely exploited for its obvious synthetic value. 

Middeldorp PJM, J de Wolf, AJB Zehnder, G Schraa (1997) Enrichment and properties of a 1,2,4-trichloro-benzene-dechlorinating microbial consortium. Appl Environ Microbiol 63 1225-1229. 

A mixed microbial community was isolated for thiophene desulfurization using enrichments from oilfield samples and showed the presence of biphenyl as a by-product. However, a pure strain could not be obtained due to over-competence by homo-acetogenic bacteria in the consortium [23],... 

A microbial biocatalyst in context of BDS is defined as a microorganism expressing enzymes capable of removing sulfur selectively from organosulfur compounds. The definition of a biocatalyst, in general, also includes use of one or more enzymes, by themselves or in a cellular extract (used either in suspended form or carrier-supported form) for removal of sulfur. Additionally, biocatalyst can be a microbial consortium as well. Aerobic as well as anaerobic pathways for sulfur removal have been reported. The anaerobic routes, however, have been plagued with lack of reproducibility preventing further development. 

Pineda-Flores, G. Boll-Arguello, G. Lira-Galeana, C., and Mesta-Howard, A. M., A microbial consortium isolated from a crude oil sample that uses asphaltenes as a carbon and energy source. Biodegradation, 2004. 15(3) pp. 145-151. 

Christensen BB, Haagensen JAJ, Heydom A, Molin S (2002) Metabolic commensalism and competition in a two-species microbial consortium. Appl Environ Microbiol 68 2495-2502... 

Jhanson R, Ackerman CE, Scow KM (1999) Biodegradation of methyl ter/-butyl ether by abacterial pure culture. Appl Environ Microbiol 65 4788-4792 Kanaly RA, Bartha R, Watanabe K, Harayama S (2000) Rapid mineralization of benzo[a]pyrcnc by a microbial consortium growing on diesel fuel. Appl Environ Microbiol 66 4205-4211... 

Middeldorp PJM, De Wolf J, Zehnder AJB, Schraa G (1997) Enrichment and properties of a 1,2,4-trichlorobenzene-dechlorinating methanogenic microbial consortium. Appl Environ Microbiol 63 1225-1229 Miller ME, Alexander M (1991) Kinetics of bacterial degradation of benzylamine in a montmorillonite suspension. Environ Sci Technol 25 240-245 Montville R, Schaffner DW (2003) Inoculum size influences bacterial cross contamination between surfaces. Appl Environ Microbiol 69 7188-7193 Mortland, MM (1970) Clay-organic complexes and interactions. Advances in Agronomy 22 75-117... 

Wu Q, Sowers KR, May HD (2000) Establishment of a polychlorinated biphenyl-dechlorinating microbial consortium, specific for doubly flanked chlorines, in a defined, sediment-free medium. Appl Environ Microbiol 66 49-53... 

Microbial systems Consortium comprised of three bacterial strains capable of degrading several textile dyes including azo dyes in a rotating biological contactor Sludge from a domestic... 

Direct Fast Scarlet 4BS Consortium of a white-rot fungus and Pseudomonas 1-10 isolated from wastewater The microbial consortium showed a significant improvement in dye decolorization rates under either static or shaking culture. The 4BS was mineralized completely [89]... 

Remazol Black B Alcaligenes faecalis, Microbial consortium immobilized [187]... 

Saratale RG, Saratale GD, Kalyani DC, Chang JS, Govindwar SP (2009) Enhanced decolorization of textile azo dye Scarlet R by using developed microbial consortium-GR. Bioresour Technol 100 2493-2500... 

Oxspring DA, McMullan G, S myth WF, Marchant R (1996) Decolorization and metabolism of the reactive textile dye Remazol-Black-B by an immobilized microbial consortium. Biotechnol Lett 18 527-530... 

Fang H, Wenrong H, Yuezhong L (2004) Investigation of isolation and immobilization of a microbial consortium for decoloring of azo dye 4BS. Water Res 38 3596-3604... 

Adsorption of azo dyes by the biomass is considered as the first step of their biological reduction [39]. Because of adsorption, the dye is concentrated onto the biomass until its saturation the amount of adsorbed dye is then proportional to the amount of biomass [4CM-2]. Steffan et al. [43] observed that 68% Ethyl Orange was rapidly adsorbed on a microbial consortium immobilized in alginate beads, but only after the addition of glucose or starch the dye was effectively degraded. 

Figure 21.2 shows how in the calculation results benzene is transported through the aquifer. The pulse of benzene migrates at the rate of groundwater flow, traversing the aquifer in ten years. As a result of biodegradation by the natural microbial consortium, however, the benzene concentration decreases markedly with time, compared to the non-reacting case. 

We take two cases in which mineral surfaces catalyze oxidation or reduction, and one in which a consortium of microbes, modeled as if it were a simple enzyme, promotes a redox reaction. In Chapter 33, we treat the question of modeling the interaction of microbial populations with geochemical systems in a more general way. 

We can, therefore, reasonably expect the degradation to behave as an enzymatically catalyzed reaction in which phenol is the substrate and the microbial consortium serves as the enzyme. As discussed in Chapter 17, reaction rate in this case can be represented as,... 

Soil Under aerobic conditions, indigenous microbes in contaminated soil produced pentachlorocyclohexane. However, under methanogenic conditions, a-BHC was converted to chlorobenzene, 3,5-dichlorophenol, and the tentatively identified compound 2,4,5-trichlorophenol (Bachmann et al., 1988). Manonmani et al. (2000) isolated a microbial consortium from sewage and soil that could completely mineralize a-BHC in 14 d at 30 °C. The acclimated consortium could degrade up to 100 mg/L of a-BHC within 72 h at a degradation rate of 58 mg/L-day. 

Beurskens, J.E.M., Dekker, C.G.C., van der Heuvel, H., Swart. M., de Wolf, and Dolfing, J. Dehalogenation of chlorinated benzenes by an anaerobic microbial consortium that selectively mediates the thermodynamic and most favorable reactions,... 

Manonmani, H.K., Chandrashekaraiah, D.H., Reddy, N.S., Elcey, C.D., and Kunhi, A.A.M. Isolation and acclimation of a microbial consortium for improved aerobic degradation of a-BHC, / Agric. Food Chem., 48(9) 4341-4351, 2000. Mansour, M., Feicht, E., and Meallier, P. Improvement of the photostability of selected substances in aqueous medium, Toxicol. Environ. Chem., 20-21 139-147, 1989. 

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