Carotenoid-derived aroma compounds

Winterhalter, P. and Rouseff, R., Carotenoid-Derived Aroma Compounds, Series, A.S. Ed., American Chemical Society, Washington, 2001, 1. 

Winterhalter B. and R. L. Rouseff (2002). Carotenoid-Derived Aroma Compounds An Introduction. Washington DC Amercian Chemical Society. 

Winterhalter, R, Rouseff, R.(2000). Carotenoid-derived aroma compounds. In P. Winterhalter R. Rouseff (Eds.),Carotenoid-derived aroma compounds an introduction (pp. 1-17). Washington, DC ACS Symposium Series 802. 

Gunata, Z., Wirth, J.L., Guo, W. and Baumes, R.L. (2002) C13-norisoprenoid aglycon composition of leaves and grape berries from Muscat of Alexandria and Shiraz culti-vars, In Carotenoid-derived aroma compounds, ACS Symp. Series 802, Am. Chem. Soc., Washington DC. 

Winterhalter, P. 1996. Carotenoid-derived aroma compounds Biogenetic and biotechnological aspects. In Biotechnology for improvedfoods and flavors, ed. G. R. Takeoka, R. Teranishi, P. J. Williams, and A. Kobayashi, 295-308. ACS Symposium Series 637. Washington, DC American Chemical Society. 

Carotenoid-Derived Aroma Compounds Biogenetic and Biotechnological Aspects... 

In the natural world, carotenoid oxidation products are important mediators presenting different properties. Volatile carotenoid-derived compounds such as noriso-prenoids are well known for their aroma properties. Examples include the cyclic norisoprenoid P-ionone and the non-cyclic pseudoionone or Neral. Carotenoid oxidation products are also important bioactive mediators for plant development, the best-known example being abscisic acid. Apo-carotenoids act as visual and volatile signals to attract pollination and seed dispersal agents in the same way as carotenoids do, but they are also plant defense factors and signaling molecules for the regulation of plant architecture. 

Pharmaceuticals are only a part of natural products derived from filamentous organisms. Filamentous fungi are also grown industrially for the production of natural products other than pharmaceuticals. Organic acids such as citric, itaconic and gluconic acids, carotenoids, taste and aroma compounds, and a variety of industrial enzymes such as amylases, lipases, dextranases and proteases are also extracted from these fungi. 

The special potential for constructing double bonds stereoselectively, often necessary in natural material syntheses, makes the Wittig reaction a valuable alternative compared to partial hydrogenation of acetylenes. It is used in the synthesis of carotenoids, fragrance and aroma compounds, terpenes, steroides, hormones, prostaglandins, pheromones, fatty acid derivatives, plant substances, and a variety of other olefinic naturally occurring compounds. Because of the considerable volume of this topic we would like to consider only selected paths of the synthesis of natural compounds in the following sections and to restrict it to reactions of phosphoranes (ylides) only. 

Tobacco, unlike most other commodities, is not produced as a food crop, but it is used for manufacture of smoking materials and other products. The essential oils in tobacco are important for impact and balance in smoking (11). Smoking pleasure is derived from a balance of nicotine and volatile components. Tobacco chemists and flavorists are certain that carotenoid derivatives contribute to smoke flavor and aroma (5) Over a hundred compounds related to carotenoids have been isolated from tobacco and tobacco smoke. 

Although the number of aroma compounds derived from acyclic carotenoids is much inferior to that of the mono- and bicyclic compounds, some of them can also be considered as breakdown products from genuine mono-, sesqui- and diterpenoids. The importance of the aliphatic isoprenoids (282) to (291) in the formation of total flavors of certain foodstuffs is not less than that of the cyclic compounds, the three methyl ketones (282), (287) and (290) which are related to the main tomato pigment lycopene were observed in tomato flavor (75). The hexahydro derivative (291) from coffee (595), jasmine oil (722) and green tea 438) is perceived as flowery and warm and can be considered as an oxidative biodegradation product of phytol and phyta-diene. 6-Methyl-3,5-heptadien-2-one (283), with a grassy and cinnamonlike aroma 438) [detected in tomato 668), the essential oil of Hama-metis leaves 383), Ceylon tea (722) and passion fruit (777)], and pseudo-ionone (288) [also isolated from passion fruit (777)] are believed to be formed from two different dehydrolycopenes. Compounds other than carotenoids, such as solanesol or squalene, can also be considered... 

Another important class of volatile compounds originating from terpenoids are the cleavage products of carotenoids which have carbon skeletons ranging from C8 to Cl 8 (Fig. 2) [9, 75]. Many of these volatile carotenoid derivatives are key aroma constituents of finits and flowers due to their extremely low aroma thresholds. For example, P-damascenone, found in numerous fruits, has a floral/finity odor with an aroma threshold of a few parts per trillion, making it one of the most potent odorants known... 

However, when the carotenoids and acylglycerols were recombined, the salmon aroma developed. Combinations of alternate sources of fish acylglycerols along with crayfish carotenoids revealed that the necessary component for salmon flavor development was the presence of carotenoids specifically derived from salmon oil (Table III). Such results strongly suggest that the compound Is derived by co-oxldatlon of fish acylglycerols with salmon carotenoids, and that the precursor Is located In the carotenoid fraction. 

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