Phenolic radioactive

The contaminants that can be removed by flotation include conventional pollutants such as BOD, COD, total suspended solids (TSS), phosphorus, phenols, oil and grease, as well as toxic pollutants including heavy metals, toxic organics, pathogenic microorganisms, and radioactive radon 22.28,33,54,64,100-102... 

The addition of a radioactive iodine atom to a protein molecule typically has little effect on the resultant protein activity, unless the active center is modified in the process. The size of an iodine atom is relatively small and does not result in many steric problems with large molecules. The sites of potential protein modification are tyrosine and histidine side chains. Tyrosine may be modified with a total of two iodine atoms per phenolate group, whereas histidine can incorporate one iodine. Sulfhydryl modification at cysteine residues is typically unstable. 

For the purpose of the following discussion, the xenobiotics studied in the dogfish shark were divided into three classes 1) those relatively hydrophilic (Table V) those relatively lipophilic (i.e., solubility in water less than 1 mg/ml, Table VI) and, 3) metal-containing pollutants (Table VII) Most of these data have been previously reported (18-23) using C compound, for assay, with the exception of sodium lauryl sulfate (SLS) ( S), cis-Pt (atomic absorption spectroscopy) and phenol red (spectrophotometry). Unless otherwise stated these data are presented as total radioactivity and the hazards of doing so are recognized (24). 

In addition to the two model substances, Table V includes similar data on two water soluble pollutants. For phenol, the hepatic compartment at 4 hrs. contained both a large concentration and a high percentage of the administered dose. As is indicated by the urine and kidney levels, the importance of the renal route is evident. While there are no other unique distributional factors noted for phenol from these data, the fact that after 24 hrs. only about 30% of the administered radioactive compound is accounted for, as well as other known properties of phenol, suggests that it may be excreted via the gills (28) or through the skin. 

Rats exposed by intratracheal instillation to [14C]-labeled phenol also demonstrated rapid absorption kinetics, with most of the radioactivity being excreted within 72 hours (Hughes and Hall 1995). 

When human skin was treated in vitro with 0.0013-0.0027 mg/cm2 [14C]-labeled phenol and left unoccluded, 20% of the radioactivity was absorbed when analyzed 72 hours later, while 7% remained on the skin surface (Hotchkiss et al. 1992). Covering the skin with a teflon cap resulted in the absorption of 47%, with 3% recovered in the skin. When rat skin was subjected to the same exposure regime in this study, 72 hours later 24% of the radioactivity was absorbed with 22% recovered in the skin when the skin was unoccluded, and 36% was absorbed with 3-4% recovered in the skin when the skin was occluded. 

Rats exposed by intratracheal instillation to radiolabeled phenol were sacrificed 72 hours later and analyzed for tissue distribution of the radioactivity (Hughes and Hall 1995). Of the radioactivity remaining in the body (1-5%), a majority was distributed in the lungs (0.13%), skin (0.13%), blood (0.07%), muscle (0.03%), fat (0.02%), and liver (0.02%). 

Experiments with the chlorine attached to a radioactively labeled carbon-14 atom produce phenol with 50 percent of the OH attached to the carbon-14 atom and 50 percent attached to the adjacent Ccirbon atom. This distribution indicates that the second attack by the hydroxide ion has equal probability of attacking either side of the triple bond, which is evidence of the existence of the triple bond, and, therefore, of the benzyne molecule. 

When radioactive lignin precursors are applied to resistant host plants infected with an avirulent pathogen, the autoradiographic localization of radioactivity in resistant reacting host cells may help to corroborate the participation of lignification in the resistance response. Thorough extraction of non-polymerized precursor with organic solvents and the removal of esterified phenolics by alkaline hydrolysis are important steps in these experiments (25,28,30,31). 

The application of radioactive phenolic precursors—quinic acid and shikimic acid (52), phenylalanine (30,53), tyrosine (53), and cinnamic acid (30,31,53)—to infected wheat leaves led to a solvent- and alkali-resistant incorporation of radioactivity into hypersensitively reacting host cells suggesting lignin formation had occurred. 

A predominant toxin (51) from water beetles of the genus llybius (Table V) shows a UV absorption corresponding to hydroxyquinoline or hydroxyiso-quinoline. The H-NMR spectrum exhibits, beside signals of methyl ester and phenol, signals of five aromatic protons as both ABC and AB systems, the latter indicating two protons at C-3 and C-4 in quinoline. Since electron pyrolysis of 51 gives radioactive 8-hydroxyquinoline, its structure is identified as methyl 8-hydroxyquinoline-2-carboxylate (51) and confirmed by synthesis from xanthurenic acid (52) (Scheme 48) (101). The precursor of this alkaloid was shown to be tryptophan (444). 

Figure 11 Tyrosine residues are subject to nucleophilic and electrophilic reactions. The phenolate ion may be alkylated or acylated using a variety of bioconjugate reagents. Its aromatic ring also may undergo electrophilic addition using diazonium chemistry or Mannich condensation, or be halogenated with radioactive isotopes such as 125I.

The INET contactors have also been applied to non-nuclear processes, such as the removal of a specific rare metal (yttrium) from other rare metals (Zhou et al., 2007), hydrocortisone from fermentation liquor (Zhou et al., 2006b), phenol from wastewater (Xu et al., 2006), and caffeine from coffee beans (Duan et al., 2006). As described by Zhou et al. (2007), the contactor rotor is driven by a motor that is not above the contactor. Instead, a belt connects the motor to the top of the rotor shaft. This design is possible because these materials are not radioactive, and hands-on maintenance is thus possible. 

The 3H labels in radioactive 147 were located at positions 2 and 4 because its oxidation to narwedine (149) followed by alumina chromatography and crystallization from MeOH, conditions which cause exchange of the hydrogen atoms ortho to the carbonyl, determined complete loss of the 3H activity. This means that in the biosynthesis the addition of the phenolic hydroxy group onto the intermediate enone 400 is not reversible or, if so, under enzymic control (100). 

Calvin and coworkers, in their classical studies of photosynthetic processes, detected labeled triose phosphates and hexose phosphates on bi-dimensional chromatograms, using phenol-water and 1-butanol-pro-pionic acid-water as solvents.120121 In addition to the detection of radioactivity, an ammonium molybdate-nitric acid color reagent was used to detect phosphorus.16 Acidic-solvent developers were used to obviate decomposition of the esters. 

Fig. 1. Distribution of radioactivity among phenolic amines during 3 months after feeding [l-14C]tyramine to a Cleopatra mandarin seedling. ( — ) Hordenine, (0—0) synephrine, (O—O) AJ-methyltyramine, and (O—O) tyramine. (Reprinted with permission from Phytochemistry, Vol. 8, T. A. Wheaton and 1. Stewart, Biosynthesis of synephrine in citrus. Copyright 1969, Per-gamon Journals Ltd.)...

Experimentally, C14-aminoacyl sRNA was incubated with rat liver microsomes or ribosomes, GTP, various fractions obtained from the nonparticulate portion of rat liver homogenates, and buffered salt-sucrose medium in a total volume of approximately 2 ml. (6-10). The C14-aminoacyl sRNA was prepared by the phenol-extraction procedure from the pH 5 amino acid-activating enzymes, fraction of rat liver after incubation with C14-L-amino acids (9, 13). C14-leucyl sRNA (approximately 1000 c.p.m.), having a specific radioactivity of approximately 55,000 c.p.m. per mg. of RNA, and containing a complement of endogenous, unlabeled, bound amino acids, was used in most of these studies. The microsomes were sedimented from the post-mitochondrial supernatant at 104,000 x g (10) and the ribosomes were prepared from them by extraction with deoxycholate (16). 

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