Antioxidant Water, pH 2.1 Trolox (1.4 [+ or -] 0.3) x [10.sup.5] (a) PMHC (1.9 [+ or -] 0.3) x [10.sup.5] (a) DBHA (f) (3.3 [+ or -] 0.4) x [10.sup.4] (a) Catechol
(3 [+ or -] 1) x [10.sup.3] (a) Antioxidant Water, pH 7.4 Trolox (4.1 [+ or -] 0.7) x [10.sup.5] (a) PMHC (2.0 [+ or -] 0.3) x [10.sup.5] (a) DBHA (f) (3.2 [+ or -] 0.4) x [10.sup.4] (a) Catechol
(7 [+ or -] 2) x [10.sup.3] (a) Antioxidant PhCl Trolox 1.1 x [10.sup.6] (b) PMHC 3.2 x [10.sup.6] (d) DBHA (f) 1.1 x [10.sup.5] (a) Catechol
5.5 x [10.sup.5] (g) Antioxidant MeCN Trolox (1.6 [+ or -] 0.2) x [10.sup.5] (c) PMHC 6.8 x [10.sup.5] (e) DBHA (f) 2.5 x [10.sup.4] (e) Catechol
2.5 x [10.sup.4] (d) (a) See ; (b) see ; (c) see ; (d) see ; (e) see ; (f) 2,6-di-tert-butyl-4-methoxyphenol; (g) see .
There is no doubt that the active principles of these compounds (8, 9) are the catechol
functional moiety presented in the 3,4-dihydroxyphenyl ethanol and caffeic acid moieties in their structures.
chlorophenols and catechol
decreased human membrane erythrocytes acetylcholinesterase activity  chlorophenol and dimethylphenol changed ATPase activity and membrane fluidity and also damaged membrane proteins [47-51].
Compound 7, with a catechol
moiety and a conjugated carbonyl group, may be bound to free enzymes and form an enzyme substrate complex.
Current research spawned from our method applies LCED methodology to measure concentrations of other catechols
such as isoproterenol, 2,3-dihydroxybenzoic acid (hydroxyl radical production), dihydroxyphenylacetic acid (main neuronal metabolite of dopamine), L-dihydroxyphenylserine (norepinephrine prodrug), and dihydroxyphenylacetaldehyde (cytotoxic metabolite of dopamine).
Early on in this work, we settled on catechols
(or ortho-hydroxyphenols) as the most promising target for the synthetic work.
Free phenolics or catechols
with orthodihydroxy compounds function effectively as iron-reducing chelators (Goodell et al.
Among others, the amphiphilic phenolic compounds, monohydroxyphenols and o-dihydroxyphenols (catechols
), are extracted.
Generally, quinones and catechols
used at levels less than 0.05% (500 ppm) can function as inhibitors by inactivating free radicals generated at the unsaturated sites in the resin or monomer.
The most popular are 2.4-dichlorophenoxyacetic acid (2,4-D) , 4-chloro-2-methylphenoxyacetic acid (mcPA)  and 2,4,5-trichloro-phenoxyacetic acid (2,4,5-T) that biodegradation leads to the formation of both phenols (phenol, 2-chlorophenol and 2,4-dichlorophenol) and catechols
coli BL21 harboring c23oB61 gene (this work) pUC19 c23oB61 [Amp.sup.r], pUC19 derivative, c23oB61 encoding mutant form of catechol
2,3- dioxygenase (C103R, K289Stop)  pET-22(b) [Amp.sup.r]; Novagen pc23oB61 [Amp.sup.r], pET-22(b) derivative, c23oB61 encoding mutant form of catechol
2,3-dioxygenase (C103R, K289Stop) (this work) TABLE 2: Specific and relative activity of wild-type (wt) and mutant C23O dioxygenases using different catechols
as the substrate.
Anti-inflammatory effects of catechols
in lipopolysaccharide-stimulated microglia cells: inhibition of microglial neurotoxicity.