Alkaloids in the plant

Both of the alkaloids anhalamine (62) from l ophophora williamsii and lophocerine (63) from l ophocereus schotti were isolated (after the properties of purified mescaline had been noted) in the search for materials of similar behavior. Interestingly, lophocerine, isolated as its methyl ether, after dia2omethane treatment of the alkaU-soluble fraction of total plant extract, is racemic. It is not known if the alkaloid in the plant is also racemic or if the isolation procedure causes racemization. 

It is interesting to note that these experiments strongly suggested that anhydrovinblastine is the biogenetic precursor of the VLB-type alkaloids in the plant, a proposal recently substantiated (47,48,82-88). 

Pyrrolizidine alkaloids in the plant Senecio vernalis have been implicated in the poisoning of cattle.13 The toxic agents in this plant include three closely related alkaloids — senecionine, senkirkin, and seneciphyllin. The structural formula of senecionine is shown in Figure 19.2. 

Belladonna, also called deadly nightshade, gets its name from its ability to dilate the pupils of the eyes. In the past women used belladonna for this purpose because they felt it made them more attractive. The word means beautiful lady in Italian. The plant is a mediumsized herb with long, dark green leaves and small purple flowers. The alkaloids in the plant come from the leaves and the root. Scopolamine and atropine are the main substances used from belladonna in medicine. They have been used as analgesics, anesthesia, and are especially useful in examining eyes. Atropine is also an antidote for some poisons. 

Heteroatom-demethylation reactions catalyzed by peroxidases could be of significant importance in the activation of drugs (xenobiotics) in plants and be responsible for some plant diseases [91]. Likewise, O-dealkylation reactions catalyzed by peroxidases may be important in the metabolism of tetrahydroprotoberberine (XV) and protoberberine (XVI) alkaloids in the plant families Berberidaceae and Ranunculaceae [50]. 

Toxic doses of the plant extract are difficult to determine due to differing concentrations of eight pip-eridinic alkaloids in the plant. The concentrations of alkaloids vary with the age of the plant. Plants up to 1-year-old have very low alkaloid content in roots, 0.15% in stems and 0.3-0.6% in the leaves. Plants in their second year have an alkaloid content of 1% in all parts of the plant. Geographic latitude and drying will also affect the coniine content of the plant. A toxic dose of coniine is estimated to be... 

The acid reacts with the alkaloids in the plant material and converts them into a salt. A good way to facilitate this reaction is to simmer the acidified soup in a slow cooker overnight leave the lid on, as we don t want any liquid to evaporate. It may take two or three such operations to get all of the alkaloids into solution. Next, we strain the plant matter first through cheesecloth, then through a paper coffee filter. The bulk roughage may now be discarded because the alkaloids we seek have migrated into the aqueous solution. 

The occurrence of alkaloids in the plant kingdom is limited to certain families. With... 

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