Enhancer degradation

Compounds that affect activities of hepatic microsomal enzymes can antagonize the effects of methyl parathion, presumably by decreasing metabolism of methyl parathion to methyl paraoxon or enhancing degradation to relatively nontoxic metabolites. For example, pretreatment with phenobarbital protected rats from methyl parathion s cholinergic effects (Murphy 1980) and reduced inhibition of acetylcholinesterase activity in the rat brain (Tvede et al. 1989). Phenobarbital pretreatment prevented lethality from methyl parathion in mice compared to saline-pretreated controls (Sultatos 1987). Pretreatment of rats with two other pesticides, chlordecone or mirex, also reduced inhibition of brain acetylcholinesterase activity in rats dosed with methyl parathion (2.5 mg/kg intraperitoneally), while pretreatment with the herbicide linuron decreased acetylcholine brain levels below those found with methyl parathion treatment alone (Tvede et al. 1989). 

It has been shown that a combination of photolytic and biotic reactions can result in enhanced degradation of xenobiotics in municipal treatment systems, for example, of chlorophenols (Miller et al. 1988a) and benzo[a]pyrene (Miller et al. 1988b). Two examples illustrate the success of a combination of microbial and photochemical reactions in accomplishing the degradation of widely different xenobiotics in natural ecosystems. Both of them involved marine bacteria, and it therefore seems plausible to assume that such processes might be especially important in warm-water marine enviromnents. 

Dick WA, RO Ankumah, G McClung, N Abou-Assaf (1990) Enhanced degradation of S-ethyl A, A -dipropyl-carbamothioate in soil and by an isolated soil microorganism. In Enhanced Bio degradation of Pesticides in the Environment (Eds KD Racke and JR Coats), pp 98-112. American Chemical Society Symposium Series 426, American Chemical Society, Washington, DC. 

Ohtsubo et al. 2003). By this means, strains were obtained that showed enhanced degradation of tri-, tetra-, and pentachlorobiphenyl. 

Sivakumar M, Pandit AB (2001) Ultrasound enhanced degradation of Rhodamine B Optimization with power density. Ultrason Sonochem 8 233-240... 

Wu et al. [12] used both microwave (MW) and ultrasound (US) methods individually and in combination to examine the combined effect. The rapid thermal effect of MW could be seen on polar chemicals and more OH radicals were produced due to US. Microwave irradiations have shown enhanced degradation effect when applied with sonication in absence of additional catalyst though the rate increased more in presence of H2O2. The rate order was found to be MW-US > MW > US. 

Ranjit KT, Willner I, Bossmann SH, Braun AM (2001) Lanthanide oxide doped titanium dioxide photocatalysts Novel photocatalysts for the enhanced degradation of p-chlorophe-noxyacetic acid. Environ Sci Technol 35 1544—1549... 

Gillham, R.W. and O Hannesin, S.F. (1994) Enhanced degradation of halogenated aliphatics by zero-valent iron. Ground Water, 36, 958-967. 

Some traces of metal and metal ions may initiate the decomposition of hydroperoxides even at room temperature. Traces of metal ions are present in almost all polymers and they may affect considerably the polymer oxidation and its subsequent degradation. The sequence of efficiency of metal ions to enhance degradation depends on its valence state and the type of its ligand, but may be postulated as follows ... 

TPMT2 G238C Alanine to proUne 0.2-0.5 Low to intermediate because of enhanced degradation of enzyme Decreased methyla-tion of AZA to inactive compounds Hematologic and GI toxicity... 

Martens, D.A. and Frankenberger, W.T., Jr. Enhanced degradation of polycyclic aromatic hydrocarbons in soil treated with an advanced oxidative process - Fenton s reagent, J. Soil Contam., 4(2) 175-190, 1995. 

Racke, K.D. and Coats, J.R. Enhanced degradation and the comparative fate of carbamate insecticides in soil. J. Agric. Food Chem., 36(5) 1067-1072, 1988. 

Walker, A. Further observations on the enhanced degradation ofiprodione and vinclozolininsoil, Pestic. Sci., 21(3) 219-231, 1987. 

Wang, T.C. and Tan, C.K. Enhanced degradation of halogenated hydrocarbons in a water-photolysis system. Bull. Environ. Contam. Toxicol, 40(l) 60-65, 1988. 

Addition of aeration and nutrients is of questionable value in disposal systems especially if installation cost and maintenance are considered. The use of other possible methods of enhancing degradation such as aerobic slime and anaerobic sludge are also questionable. 

Albertsson observed slightly enhanced degradation for HOPE versus LDPE, which she attributes to less branching and probably slightly lower molecular weight. 

Pancreatin Enhanced degradation of dietary carbohydrate, fat and protein... 

In six types of soils, Somasundaram et al. (1991) reported that diazinon was hydrolyzed to 2-isopropyl-6-methyl-4-hydroxypyrimidine and that the degradation product was significantly more mobile in these soils than its parent compound diazinon. In an earlier study, Somasundaram et al. (1989) found that prior applications of 2-isopropyl-6-methyl-4-hydroxypyrimidine did not enhance degradation of diazinon. 

Many chemicals important to genetic research have been produced at high levels, e.g. DNA ligase production in E. coli can be enhanced several hundred fold. Other enzymes can also be produced for industrial use and enhanced degradative ability has been generated for instance, enhanced petroleum degraders can be added to oil spills to accelerate clean-up operations. However, it is in the production of medically related compounds that this technology has been most successfully applied as, for example, in the production of insulin. 

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