Kinetics of biodegradation

Linear alkylbenzenesulfonate showed no deleterious effect on agricultural crops exposed to this material (54,55). Kinetics of biodegradation have been studied in both wastewater treatment systems and natural degradation systems (48,57,58). Studies have concluded that linear alkylbenzenesulfonate does not pose a risk to the environment (50). Linear alkylbenzenesulfonate has a half-life of approximately one day in sewage sludge and natural water sources and a half-life of one to three weeks in soils. Aquatic environmental safety assessment has also shown that the material does not pose a hazard to the aquatic environment (56). 

Haller HD, RK Finn (1978) Kinetics of biodegradation of /)-nitrobenzoate and inhibition by benzoate in a pseudomonad. Appl Environ Microbiol 35 890-896. 

Simkins S, R Mukherjee, M Alexander (1986) Two approaches to modeling kinetics of biodegradation by growing cells and application of a two-compartment model for mineralization kinetics in sewage. Appl Environ Microbiol 51 1153-1160. 

There can be no doubt that there is an important seasonal factor in LAS biodegradation in coastal areas, as other authors have indicated previously [4,7]. Temperature variations are only relevant in shallow coastal systems. In these areas, LAS will probably be efficiently removed from the water column in summer time, whereas degradation could be less extensive during winter months due to the lower kinetics of biodegradation under these conditions, which permits access to sediments of a higher proportion of the LAS present. 

The yield (y) of a biomass production process is defined as the moles of biomass formed per mole of substrate consumed. Aerobic conditions are more conducive to higher biomass formation (and therefore also to biofilm formation) than anaerobic conditions. Empirically, under aerobic conditions, a yield of 0.05 - 0.6mol biomass/mol carbon can be obtained, while under anaerobic conditions the attainable yield falls to 0.04 -0.083mol. The reaction kinetics of biodegradation processes can be approximated by the first-order reaction rate constant k as follows ... 

Beltrame, P., Beltrame, P.E., and Cartini, P. Influence of feed concentration on the kinetics of biodegradation of phenol in a continuous stirred reactor, Water Res., 18(4) 403-407,1984. 

Scow, K. M. (1993)- Effect of sorption-desorption and diffusion processes on the kinetics of biodegradation of organic chemicals in soil. In Sorption and Degradation of Pesticides and Organic Chemicals in Soil, ed. D. M. Linn, T. H. Carski, M. L. Brusseau F-H. Chang, pp. 73-114. Madison, WI Soil Science Society of America, American Society of Agronomy. 

Scow, K. M. Alexander, M. (1992). Effect of diffusion on the kinetics of biodegradation experimental results with synthetic aggregates. Soil Science Society of AmericaJournal, 56, 128-34. 

Schmidt, S.K., S. Simkins, and M. Alexander. 1985. Models for the kinetics of biodegradation of organic compounds not supporting growth. Appl. Environ. Microbiol. 50 323-331. 

Scow KM, Schmidt SK, Alexander M. 1989. Kinetics of biodegradation of mixtures of substrates in soils. Soil Biol Biochem 21 703-708. 

Yerushalmi L, Guiot SR (1998) Kinetics of biodegradation of gasoline and its hydrocarbon constituents. Appl Microbiol Biotechnol 49 474-481... 

FIGURE 10.3 The kinetics of biodegradation of DOM from green manure (GM) and sewage sludge (Slu) in the contaminated sandy loam under aerobic and waterlogged incubation at 22 1°C. 

Lotfabad, S. K. Gray, M. R. (2002). Kinetics of biodegradation of mixtures of polycyclic aromatic hydrocarbons. Applied Microbiology and Biotechnology, 60, 361-5. 

This model considers the biological step only, i.e. the activated sludge reactor and the secondary settling. The model allows calculation of the concentration of LAS in the treated effluent, as a function of key plant operating parameters, Henry s Law constant, the partitioning coefficient solids/MLSS and kinetics of biodegradation of LAS. 

Pentose-based surfactants are not considered as toxic or harmful in acute toxicity tests. APP also have uses in dishwashing and laundry detergents, cosmetics, and cleaning products which are discharged into domestic wastewater after use and thus enter the aquatic environment. It has been shown that pentose derivatives have good kinetics of biodegradation compared with conventional surfactants [35]. The production of pentose-based surfactants requires 37 1% less fertilizers and 36-57%... 

In comparison to a conventional blend, the biodegradation of a multilayer is modified because of the stratification of its phases. The polyester-based skin first needs to be pierced for the micro-organisms to reach the core of the material, which will then biodegrade rapidly. The kinetics of biodegradation is therefore very specific, and depends, in this case, on the polyester which is used. Thus, it can also be modulated [GAT 02]. 

M. Alexander and K. M. Scow, Kinetics of Biodegradation, B. L. Sawhney, and K. Brown (eds.). in Reactions and Movement of Organic Chemicals in Soils. Soil Science Society of America Special Publication, Number 22, Chap. 10, 1989. 

Agrawal, C. M., McKinney, J. S., Lanctot, D., and Athansiou, K. A. (2(KX)), Effects of fluid flow on the in vitro degradation kinetics of biodegradable scaffolds for tissue engineering. Biomaterials 21(23) 2443-24S2. 

The results suggest that the temperature is the predominant parameter that governs the fungal degradation of poly(/-lactide). In real compost, the kinetics of biodegradation of the poly(/-lactide) is synergetic between bacteria and fimgi. 

The kinetics of biodegradation is affected by physical parameters like degree of crystallinity, porosity, surface area, and pore size distribution. A striking example is the difference in solubility between amorphous and polycrystalline silicon (Shabir et al. 2011). 

Papanastasiou AC (1982) Kinetics of biodegradation of 2,4-dichlorophenoxyacetate in the presence of glucose. Biotechnol Bioeng 24 2001—2011... 

T. M. Wu, eS. F. Hsu, Y. F. Shih, and C. S. Liao, Thermal degradation kinetics of biodegradable poly (3-hydroxybutyrate)/layered double hydroxide nanocomposites. Journal of Polymer Science, Part B Polymer Physics, 46 (2008), 1207-13. 

The measured kinetics of biodegradation of a single organic compound as sole carbon source in a batch reactor depend on the history of the culture, the identifi-ability of the parameters, and the manner in which the experiment to measure them is run. The initial substrate to biomass ratio used in the experiment is particularly important because it influences both parameter identifiability and the expression of the culture history. 

---