Mutagens, natural

Chloroxymorphamine (/3-COA), 191 (R = Me), on the other hand, produced irreversible agonist responses(307) also, presumably by an alkylating mechanism. Alkylation probably occurs from attack by a receptor nucleophilic group upon a mediating aziridinium ion. The mutagenic nature of compounds capable of generating aziridinium ions is likely to render compounds of this sort unacceptable for human therapy. 

Auerbach, C and J.M. Robson. 1946. Chemical production of mutagens. Nature (Lond.) 157 302. 

Parry JM, Tweats DJ, Al-Mossawi MAJ (1979) Monitoring the marine environment for mutagens. Nature (Lond) 264 538-540... 

J. W. Allen and S. A. Latt, Analysis of sister chromatid exchange formation in vivo in mouse spermatogonia as a new test system for environmental mutagens, Nature (London) 260, 449-451 (1976). 

Stevioside and rebaudioside A are diterpene glycosides. The sweetness is tainted with a bitter and undesirable aftertaste. The time—intensity profile is characteristic of naturally occurring sweeteners slow onset but lingering. The aglycone moiety, steviol [471 -80-7] (10), which is the principal metaboHte, has been reported to be mutagenic (79). Wide use of stevia ia Japan for over 20 years did not produce any known deleterious side effects. However, because no food additive petition has been presented to the FDA, stevioside and related materials caimot be used ia the United States. An import alert against stevia was issued by the FDA ia 1991. In 1995, however, the FDA revised this import alert to allow the importation and use of stevia as a diet supplement (80), but not as a sweetener or an ingredient for foods. Several comprehensive reviews of stevia are available (81,82). 

We have proposed that gastric cancer may be the end result of a series of mutations (or similar cell transformations) begun many years before cancer becomes clinically apparent. The mutagens could be nitroso compounds synthesized situ from nitrite and naturally-occurring nitrogen-containing compounds. 

H. Czeczot, B. Tudek, J. Kusztelak, T. Sz.ymczyk, B. Dobrowolska, G. Glinkowska, J. Malinowski, and H. Strzeiccka, Isolation and studies of the mutagenic activity in the Ames test of flavonoids naturally occurring in medical herbs. Mutat. Re.s. 240 209 (1990). 

The abasic sites (3, Scheme 8.2) resulting from the loss of alkylated bases from DNA are both cytotoxic and mutagenic. " The cyclic acetal (3) exists in equilibrium with small amounts (—1%) of the open chain aldehyde (4). The acidic nature of a-proton in the aldehyde form of the abasic lesion facilitates 3-elimination of the 3 -phosphate residue to yield a strand break. " This reaction occurs with a half-life of about 200 h under physiological conditions (pH 7.4, 37°C), but can be accelerated by heat, basic conditions, or the presence of various amines. " ... 

Quercetin is a naturally occurring flavonoid with both antioxidant and prooxidant activities (Scheme 10.12).90 It has been demonstrated in a variety of bacterial and mammalian mutagenicity experiments that quercetin has mutagenic properties that could be related to quinoid formation.91,92 Quercetin is initially oxidized to an o-quinone, which rapidly isomerizes to di-QMs that could also be called extended... 

Naturally, no standard test system can cover the practically unlimited number of cases when a given pesticide may prove to be mutagenic. Pesticides are among the most mutagenic substances introduced by humans into the environment [75]. Mutagenic activities are inherent to an... 

We should emphasize once more - every pesticide, when studied using a number of test systems, displays mutagenic activity. All pesticides are dangerous mutagens for the natural environment. 

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