Leffingwell &
Associates
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A Review by John C. Leffingwell, Ph.D.
This a part of our series on aroma materials produced by carotenoid degradation.
Undoubtedly due to health and social concerns, tobacco has been the most thoroughly researched natural product in history. We believe that well over U.S. 100 million dollars has been expended in the study of tobacco constituent composition. Over 2700 compounds have been identified in various tobacco varieties (Virginia, Burley and Oriental) and it is estimated that in excess of 6000 may be in tobacco smoke.
The study of tobacco constituents has identified seminal knowledge of importance to our understanding of plant constituents (e.g., identification and structural elucidation of the ubiquitous plant constituent, solanesol), the first identification of the class known as cembranoids, the finding that novel sugar esters in the leaf waxes act as both insect repellent and as the aroma precursor for Oriental tobacco, the discovery of 2-acetylpyrazine with its characteristic "popcorn" aroma, and especially to our knowledge of carotenoid degradation which is of importance to the flavor and aroma of many flowers and foodstuffs. In addition, our knowledge of genetic engineering was pioneered through use of the tobacco plant.
This review focuses solely on the aspect of potential aroma constituents produced by carotenoid degradation and does not touch on the many other classes of compounds in tobacco.
The following charts provide an overview of various aroma constituents produced in tobacco leaf via oxidative carotenoid degradation.
Aroma Properties of Selected Tobacco Carotenoid Derivatives
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beta-Ionone |
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alpha-Ionone |
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beta-Damascone |
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beta-Damascenone |
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Oxo-Edulan I |
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Oxo-Edulan II |
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Theaspirone |
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4-Oxo-beta-ionone |
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3-Oxo-alpha-Ionone |
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Dihydroactinodiolide |
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Safanal |
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beta-Cyclocitral |
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References
Wahlberg, I. and C.R. Enzell, Tobacco Isoprenoids, Natural Product Reports, Vol. 4 (No. 3), 237-276 (1987).
Enzell, C.R.; I. Wahlberg and A.J. Aasen, Isoprenoids and Alkaloids of Tobacco, Progress in the Chemistry of Organic Natural Products, 34, 1-79 (1977).
Mookherjee, B.D. and R.A. Wilson, Tobacco Constituents - Their Importance in Flavor and Fragrance Chemistry, Perfumer & Flavorist, 5(1), 27-51 (1990).
Leffingwell, J.C. and D. Leffingwell, Chemical and Sensory Aspects of Tobacco Flavor - An Overview, Rec. Adv. Tob. Sci., 14, 169-218 (1988).
Tobacco Ingredients List - Access the List of Ingredients used in Cigarettes as discosed in the 1994 U.S. Tobacco Industry List - via The Brown & Williamson Site
Download Chemical Constituents of Tobacco Leaf and Differences among Tobacco Types, Leffingwell Reports, Vol. 1 (No.3), 2000 (pdf file 450KB)
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