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Composition et caracteristiques chimiques de coffea sauvages de Madagascar, 2; 3

by D'Ornano, M; Chassevent, F; Pougneaud, S; Association Scientifique Internationale du Café, París (Francia); 3. Colloque International sur la Chimie des Cafés Verts, Torrefies et Leurs Derives Trieste 2-9 Jun 1967.
Publisher: París (Francia) 1968Description: p. 101-114.Subject(s): ANALISIS QUIMICO | COMPOSICION | GRANOS | CAFEINA | COMPOSICION DEL GRANO | CAFE SILVESTRE | GRAIN | CAFFEINE | GRAIN | CAFEINESummary: II. Although a previous study showed that the main wild coffee trees of Madagacar did not contain appreciable amounts of caffeine in their seeds, it was important to look for in the leaves of the coffee trees, the usual place for caffeine production in cultivated coffee trees, the possible existence of a normal cycle of caffeine biosynthesis, for which only the final stage, respresented by the caffeine, would be different or, on the contrary a totally different cycle. For this purpose, ammonia-chloroform extracts of the leaves of the cultivates coffee trees (Arabica, Congusta, Excelsa) and the wild coffee trees (Farafanganensis, Vatovavyensis, Millottii, Buxifolia, Mangoroensis, Lancifolia) are analysed by spectrophotometry and paper chromatography under various conditions, as well as extracts from the seeds of cultivated coffee trees (Arabica, Robusta, Excelsa). It is shown that the leaves of cultivated coffee trees seem to embody a normal sequence of caffeine elaboration (santhine, theobromine, theophylline, caffeine) while the leaves of wild coffee trees do not apparently contain either caffeine or methylxanthines. The same applies to C. excelsa, whose leaves are in this respect allied to those of wild coffee trees, while its seeds, like those of other cultivated coffee trees seem to contain xanthine as well as caffeine. III. The cation eluates of the water extracts of three wild coffee trees (Buxifolia, Resinosa, Mauritiana) are analysed by paper and column chromatography; all three contain some trigonellin, two of them (Buxifolia and Resinosa), some cafamarine, and the third (Mauritiana) a substance very like cafamarine but seemingly free of bitterness
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++Ilus. Dat. num. 22 ref. Sum. (De, En, Fr)

II. Although a previous study showed that the main wild coffee trees of Madagacar did not contain appreciable amounts of caffeine in their seeds, it was important to look for in the leaves of the coffee trees, the usual place for caffeine production in cultivated coffee trees, the possible existence of a normal cycle of caffeine biosynthesis, for which only the final stage, respresented by the caffeine, would be different or, on the contrary a totally different cycle. For this purpose, ammonia-chloroform extracts of the leaves of the cultivates coffee trees (Arabica, Congusta, Excelsa) and the wild coffee trees (Farafanganensis, Vatovavyensis, Millottii, Buxifolia, Mangoroensis, Lancifolia) are analysed by spectrophotometry and paper chromatography under various conditions, as well as extracts from the seeds of cultivated coffee trees (Arabica, Robusta, Excelsa). It is shown that the leaves of cultivated coffee trees seem to embody a normal sequence of caffeine elaboration (santhine, theobromine, theophylline, caffeine) while the leaves of wild coffee trees do not apparently contain either caffeine or methylxanthines. The same applies to C. excelsa, whose leaves are in this respect allied to those of wild coffee trees, while its seeds, like those of other cultivated coffee trees seem to contain xanthine as well as caffeine. III. The cation eluates of the water extracts of three wild coffee trees (Buxifolia, Resinosa, Mauritiana) are analysed by paper and column chromatography; all three contain some trigonellin, two of them (Buxifolia and Resinosa), some cafamarine, and the third (Mauritiana) a substance very like cafamarine but seemingly free of bitterness

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