Occurrence in the plant

Cannabinoids are highly lipophilic compounds making bioavailabihty very dependent on the formulation and the mode of administration. Cannabinoid occurrence in the plant is predominantly in the form of the carboxyhc acids, which are pharmacologically totally different and rather unstable, decarboxy-lating over time to their active neutral form. The carboxyhc acids, although not active at the CB receptor, nevertheless add to the overall effect as they possess antibiotic and anti-inflammatory effects. 

Fifty years after the discovery of apiose, a review of the literature1 showed that it was still a curiosity, and had been found only in the parsley plant. Apart from its structure, and those of the flavonoids from which it was isolated (primarily, apiin), little else was known about apiose. In the next two decades, this branched-chain sugar was shown to have very widespread occurrence in the plant kingdom, being identified, in most of the plants investigated,4-6 by paper chromatography. 

Among the branched-chain sugars shown in Table I, apiose (1) and hamamelose (2), respectively found in parsley and witch hazel early in this century, are now known to have widespread occurrence in the plant... 

The numerous biological activities of saponins, as well as their widespread occurrence in the plants and the hundreds structures described so far, prompted the development of a strategy for their rapid, highly sensitive and, if possible, non degradative, structure elucidation. 

Vincken JP, Heng L, de Groot A, Gmppen H. Saponins, classification and occurrence in the plant kingdom. Phytochemistry 2007 68 275-297. 

Since the first isolation and identification of brassinolide (BR) from rape pollen by Grove et al in 1978 (7), a wide occurrence in the plant kingdom of related steroidal compounds which are now collectively called brassinosteroids, as well as BR itself, has been confirmed (2). 

One feature relating to the constitution of the pyrrolizidine alkaloids which has assumed increased importance is the occurrence in the plant, now recognized as general (146), of the alkaloid W-oxides. Trachel-anthamine A-oxide (trachelanthine) was the first such compound to be isolated and identified, along with trachelanthamine, from Trachel-anthus korolkovi Lipsky (56-56c), and iV-oxides have since been found... 

Authors acknowledge die investigative work carried out by various Task Forces to systematically analyse tire imusual occurrences in the plant. Field work carried out by the personnel of Reactor Operation and Maintenance Group is also gratefully acknowledged. 

Table 1. Photosynthetic pigments and their occurrence in the plant kingdom...

Widespread occurrence in the plant world, particularly in heartwood, bark and roots, e.g. the Bigononiaceae and various Tabebuia, Tecomella and Tectona spp. Anticoagulant with anticancer activity said to be comly. available in Brazil as an anticancer agent but has... 

---