Plant Family

Early investigators grouped alkaloids according to the plant families in which they are found, the stmctural types based on their carbon framework, or their principal heterocycHc nuclei. However, as it became clear that the alkaloids, as secondary metaboUtes (30—32), were derived from compounds of primary metabohsm (eg, amino acids or carbohydrates), biogenetic hypotheses evolved to link the more elaborate skeletons of alkaloids with their simpler proposed pregenitors (33). These hypotheses continue to serve as valuable organizational tools (7,34,35). 

The latter is the source of the Chinese dmg Chin-Shih-Hu. Compared to the other families of bases discussed eadier, the numbers of alkaloids supposedly derived from famesyl pyrophosphate or a close relative is small. However, given the wide variety of plant families containing sesquiterpenes, it is most likely that the numbers of compounds to be found will dramatically increase. 

The isolation and structural characterization of plant constituents are often difficult and time-consuming. Consequently, at the present time, only a small percentage of the total number of natural plant products has been identified. Early in the development of natural product chemistry it was apparent to many botanists and chemists that plants might be characterized and classified on the basis of their chemical constituents. The distribution of chemical constituents among plant families is presented by Swain (139) and Hegnauer (66). 

Pyrazol-1 -ylalanine, an isomer of histidine, was isolated from Citrullus vulgaris (watermelon) seed and its structure was confirmed by comparison with synthetic material 107). It was the major free amino acid in the dormant dry seed but was present in only trace amounts in vegetative tissue. While present in seed extracts of other members of the Cucurbitaceae, it has not been identified as occurring in members of other plant families. 

Lactones. Physiologically active lactones such as parasorbic acid, coumarin, scopoletin, and protoanemonin occur in many plant families (Figure 2). The lactones may perform a regulatory function in the plant, and have been shown to inhibit germination and to repress root growth [reviewed in detail by Hemberg 61), Evenari 36,37), and Borner 12)]. 

The archaic flowering plant family Degeneiiaceae its bearing on an old enigma. 

Plants causing allergenic reactions by inhalation of pollen grains are numerous and widely distributed. Plant families whose pollen causes allergic reactions include Gramineae,... 

The tropane alkaloids occur mainly in the plant family Solanaceae but are also found in the families Convolvufaceae, Erythroxylaceae, Proteaceae, and Rhizophoraceae. In addition, the presence of tropane alkaloids has occasionally been indicated in the families Euphorbiaceae and Cruciferae (cf. Tables II and III). For a detailed account of the distribution of tropane alkaloids among species, interested readers should consult Refs. (15-23) and references therein. 

The compounds are listed in order of increasing molecular weight. In most cases the references refer to articles where the occurrence of the compound was indicated for the first time or its rediscovery in a new plant family was announced. Where the compound has been mentioned in earlier chapters of this treatise, the review reference is usually given, together with some recent supplementary references. 

Table 15.1 List of common vegetable, herb and spice plant families and example species... 

One of the best studied tryptamine derivatives is DMT (37). DMT and 5-OMeDMT (59) are probably the active constituents of a variety of South American hallucinogenic snuffs. These and related indolealkylamines have been detected in members of at least five different plant families Agaricaceae, Leg-uminosae, Malpighiaceae, Myristicaceae and Rubiaceae (107,109,110,187). In... 

Most botanists divide the plant family Apocynaceae into three subfamilies Plumerioideae, Cerberoideae, and Echitoideae. Alkaloids have been isolated from species belonging to all of these subfamilies however, indole alkaloids have been found only in the Plumerioideae. This subfamily is further divided into seven tribes, and indole alkaloids are present only in four of these, namely, Carisseae, Tabemaemontaneae, Alstonieae (Plumerieae), and Rau-wolfieae. 

The best book describing essential oils and their extraction is The Essential Oils Individual Essential Oils of the Plant Families (in six volumes) by Ernest Guenther, 1948 (reprinted 1972-1998). 

From recent work, we do know that chemical signals from the seeds direct the ants selections. Although the story is still incomplete, an extraordinary finding has been that a chemical compound called MMS (methyl 6-methylsalicylate) is present in the seeds the ants choose. MMS is found in the seeds of the ten or twelve unconnected species from seven plant families that flourish in Peruvian ant gardens. The ants seem to find this compound irresistible. Offered inert particles coated with MMS, they become excited, pick up these decoy seeds, and occasionally carry them about. 

Czaja, A. T. (1978). Structure of starch grains and the classification of vascular plant families. Taxon T1,463 70. 

No Plant family name Plant genus and species name YCp50 Galactose RAD52 Galactose RAD52 Glucose... 

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