Conversion of Nicotine to Nornicotine in Grafts between Cherry-red Tobacco and Related Materials.
نویسندگان
چکیده
A variant designated "cherry-red" is frequently observed in common flue-cured tobacco varieties. This variant has a dappled red coloration of the cured leaf. Cherry-red and red-free selections have been obtained from Nicotiana tabacum, L. cv. 401. Analysis of these selections for alkaloids showed that the cherry-red selection had a much higher nornicotine content than the red-free selection. Conversion of nicotine to nornicotine was studied by Wada (6) in cherry-red and red-free selections from Bright Yellow variety (a Japanese flue-cured variety). He reported a substantial increase in nornicotine content of the cherry-red selection during flue-curing which coincided with development of the red pigment and suggested a correlation between them. The involvement of nornicotine in the formation of the red color complex is supported by the work of Penn et al. (5) who reported the in vitro synthesis of a cherry-red pigment when nornicotine was present in model systems in which chlorogenic acid was being oxidized by polyphenoloxidase or peroxidase. A definite correlation between the incidence of cherry-redness and nornicotine content in cured leaves of a family segregating for cherry-red was reported by \Veybrew et al. (7). Weybrew and Mann (3) compared the chemical composition of various tobacco varieties and their hybrids with Nicotiana sylz-estris, Speg. et Coin. They reported the total alkaloid content of the hybrid was greatly reduced below that of the parent tobacco variety and the alkaloid composition altered with a relatively large proportion as nornicotine. This paper reports a study of the grosser aspects
منابع مشابه
Genetic Parameters Estimates Associated to Conversion of Nicotine to Nornicotine in Burley Tobacco
Nicotine represents the predominant alkaloid in cultivated tobacco. In burley varieties, during senescence and curing of leaves, nicotine can be converted to nornicotine, which is highly undesirable because of its relationship with the tobacco specific nitrosamines formation. Thus, an alternative for producing varieties with low or null nornicotine content would be to select plants or progenies...
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A range of endemic Nicotiana species are chewed as a smokeless tobacco by several Aboriginal populations of Australia. In tobacco research, nicotine to nornicotine conversion is important because nornicotine lowers tobacco quality and is detrimental to health. A diverse group of cytochrome P450 genes with different transcriptional regulations are involved in this conversion. The primary aims of...
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Nornicotine production in Nicotiana tabacum is undesirable because it is the precursor of the carcinogen N'-nitrosonornicotine. In some individual burley tobacco plants, a large proportion of the nicotine can be converted to nornicotine, and this process of nicotine conversion is mediated primarily by enzymatic N-demethylation of nicotine which is controlled mainly by CYP82E4. Here we report a ...
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ورودعنوان ژورنال:
- Plant physiology
دوره 40 1 شماره
صفحات -
تاریخ انتشار 1965