Microbial succession

Fries MR, GD Hopkins, PL McCarty, LJ Forney, JM Tiedje (1998a) Microbial succession during a field evaluation of phenol and toluene as the primary substrates for trichloroethene cometabolism. Appl Environ Microbiol 63 1515-1522. 

Biddanda, B.A., and Pomeroy, L.R. (1988) Microbial aggregation and degradation of phytoplankton-derived detritus in seawater. I. Microbial succession. Mar. Ecol. Prog. Ser. 42, 79-88. 

Sweerts, I., R. C. Kelly, I. Rudd, R. Hesslein, and T. Cappenberg. 1991. Similarity of whole-sediment diffusion coefficients in freshwater sediments of low and high porosity. Limnol. Oceanogr. 36 335-342. Swift, M. I. 1982. Microbial succession during the decomposition of organic matter. In R. G. Burns and I. H. 

While the exact mechanism by which orange bloom fouling can facilitate corrosion is stiU a matter of debate, it is believed that microbial succession between SRB and SOB could be one of most likely mechanisms. 

Phase 1 is the chemical corrosion phase, where no bacteria are involved. In this phase, due to the combined effect of hydrogen sulfide and atmospheric carbon dioxide, concrete s pH is highly reduced to less than 10. In phase 2, the first stage of microbial succession starts, where a certain species of SOB neutrophilic sulphur-oxidizing bacteria (NSOM) further reduces pH, resulting in the... 

Typical of the microbial succession in sauerkraut fermentation, the so-called betabacteria (heterofermentative lactobacilli such as U>. brevis with higher acid and salt-tolerance than L. mesenteroides) will gradually dominate the population accompanied by a reduction in viable Leuconostoc numbers. The length of the first two stages of sauerkraut fermentation is determined by the temperature, but typically ranges from 3 to 6 days, and is associated with an increase in lactic acid up to around 1% (Muller, 1988). 

Jeong, S. H., Jung, J. Y., Lee, S. H., Jin, H. M., Jeon, C. O. (2013). Microbial succession and metabolite changes during fermentation of dongchimi, traditional Korean watery kimchi. International Journal of Food Microbiology, 164,46-53. 

More precisely, it is a process that can be schematically shown (Figure 8.2). The MID-assisted deterioration of concrete can happen in three phases. To date, nothing is known regarding the time intervals between each step, but it seems that the concrete becomes vulnerable first by chemical corrosion (deterioration) because of factors such as the formation of carbonic acids. This will lower the pH from above 12.0 to somewhere around 9.0-9.5. Then microbial succession starts, where neutrophilic SOB are replaced by another group of SOB which are capable of further reducing the pH, thus dissolving the concrete. 

Phase 2 First stage of microbial succession where, provided that sufficient nutrients, moisture and oxygen exist, some species of sulphur-oxidising bacteria (e. g., Thiobacillus sp.) can attach themselves onto the concrete surface and grow. Mostly, these species of SOB are neutrophilic sulphur-oxidising bacteria (NSOM). These bacteria produce some acidic products and convert the sulphides present to elemental sulphur and polythionic acids. 

Phase 3 The second step of microbial succession, it normally follows Phase 2 where the pH has been reduced fairly. Another species of SOB known as acidophilic sulphur-oxidising bacteria (ASOM) such as T. thiooxidans colonise the concrete surface and further reduce the acidity. It has been proposed that during Phase 2 the NSOM reduces the pH to 4.0 where during Phase 3, the pH is further reduced by the ASOM to 1.0 or 2.0 [28]. 

Studies show that microbial succession can start with very low numbers of both types of the sulphur-oxidising bacteria so that MID can develop completely [27]. Quoting from Bock and Sands work, Rogers et al. reported that a cell density of chemolithotrophic SOBs such as Thiobacillus of about 10 to 10 cells per grams of concrete is required before MID is detected [27]. 

Fig. 3.2 Microbial succession (a) and metabolic activities (b) of the key factors in the cocoa bean fermentation ecosystem. Dashed lines (b) represent the substrates present in the cocoa pulp-bean mass full lines represent metabolites produced by the microorganisms present...

Microbial Succession Patterns During Lambic Beer Fermentation... 

Moreira, I.M., Miguel, M.G., Duarte, W.F., et al. (2013) Microbial succession and the dynamics of metaboUtes and sugars during the fermentation of three different cocoa (Theobroma cacao L.) hybrids. Food Res Int 54, 9-17. 

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