Slow degradation microorganisms

The rate and extent of pesticide metaboHsm can vary dramatically, depending on chemical stmcture, the number of specific pesticide-degrading microorganisms present and their affinity for the pesticide, and environmental parameters. The extent of metaboHsm can vary from relatively minor transformations which do not significantly alter the chemical or toxicological properties of the pesticide, to mineralisation, ie, degradation to CO2, H2O, NH" 4, Cf, etc. The rate of metaboHsm can vary from extremely slow (half-life of years) to rapid (half-life of days). 

Oxygenate-degrading microorganisms are typically slow growing and may not be present natively at all sites pilot or treatability studies may be needed to confirm the applicability of bioremediation at a specific site. 

Fixed-biofilm processes offer the advantage of high concentrations of biomass in relatively small reactors, as little biomass is lost in the effluent. The result is a long solids retention time (necessary to foster slow-growing microorganisms) and the possibility of degrading hazardous contaminants or wastes with low concentrations of organics. 

PVA is the only C-C backbone polymer that is biodegradable imder both aerobic and anaerobic conditions. However, the degradation rate under natural environmental conditions, if in the absence of PVA degrading microorganisms is too slow. The PVA with sugar pendants might be a new approach to improve the biodegradability of PVA. 

In slow filtration, much of the effect is obtained by the formation of a filtration layer, including the substances that are extracted from the water. At the early stages of the operation, these substances contain microorganisms able to effect, beyond the filtration, biochemical degradation of the organic matter. This effect also depends on the total surface of the grains forming the filter material. The probability of contact between the undesirable constituents of the water and the surface of the filter medium increases in proportion to the size of the total surface... 

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