High alkaloids

The simple ohservahon that white seeds are sweeter that black seeds was used in the construction of a practical method of judging lupine seeds qualitatively. This method cannot he used with confidence, because, especially in white lupine, even very white seeds can have a high alkaloid content. On the other hand, plants from the same species are sweet . In some species, for example in the case of L. angustifolius or l. luteus, the tendency of white seeds to be sweet is more likely but not absolutely certain. 

In 1954, Stomberg isolated 5-methoxy-DMT from seeds of A. pere-grina. Later, DMT, DMT-N-oxide and 5-hydroxy-DMT-N-oxide were also found in A. peregrma. Additional components contributing to psychoactivity have been identified these also appear in about the same proportions in the Virola species used to make paricd. However, a Waikd snuff made from V. theiodora resin has an unusually high alkaloid content of up to 11 percent, consisting mainly of 5-methoxy-DMT (8 percent) and substantial amounts of DMT. 

For the extraction of L-hyoscyamine, Egyptian henbane, Hyoscyamus muticus, is used, owing to its high alkaloid content 0.5-1.5%. 

Alkaloid drugs with medium to high alkaloid contents ( 1%)... 

Even if the alkaloid content is quite high, an important step in the establishment of root cultures is the selection of the best clones which combine good growth and high alkaloid production. The occurrence of clonal variations allows the selection of high-producing lines. Mano et al. [78] were able to select a clone of hairy roots of Duboisia leichhardtii, producing 2.1 % DW scopolamine, more than twice the amount found in the leaves of the non-transformed plants. 

Petri dishes inoculated with an inner piece from the ergot will form many cultures, many will be contaminated, others will be non-heterokaryotlc, many will form spores (condia) and not form alkaloids. Strain selection is necessary to isolate a strain which will be a high alkaloid producer. 

Induction and production media are used in a two-stage process in the first stage biomass is produced, and the second stage allows alkaloid production. Morris, however, selected conditions for a Catharanthus roseus culture in which high alkaloid accumulation could be combined with high biomass accumulation (37). 

The production in Hyoscyamus hairy roots was reported to be stable during at least 10 subcultures (337). Hairy root cultures of Scopolia japonic a were selected for high alkaloid production. Media were optimized for growth and alkaloid production. One cell line, SI, produced scopolamine as the major alkaloid (0.5% of DW) the productivity was approximately 17 mg/liter in 4 weeks. Cell line S22 had atropine as the major alkaloid (1.3% of DW), from which a productivity of about 117 mg/liter in 4 weeks can be calculated (347,348). A similar productivity for atropine was found in Datura stramonium hairy roots (50-100 mg/liter in 4 weeks) (314,317). The Datura roots excreted about 5% of the atropine into the medium in the stationary phase this increases to about 30% with a concomitant decrease in total alkaloids (317). Datura wrightii was found to produce about 180 mg/liter of atropine, a production which was reached after only 15 days, which is considerably faster than the 45 days after which maximum alkaloid production is achieved in D. stramonium (317). 

The enzyme which follows the vinorine synthase was commonly named vinorine hydroxylase. VH is responsible for the generation of vomiienine (29) by selective hydroxylation of vinorine (17) at the C-21 position (Figure 18). The reaction is catalyzed exclusively by a microsomal protein from Rauvolfia cultured cells in the presence of the substrate vinorine, NADPH, and O2. The investigation of the taxonomical distribution of the enzyme indicated that vinorine hydroxylase is exclusively present in ajmahne-producing plant cells. It was also observed that the substrate specificity of VH was high. Alkaloids with vinorine-related structures such as fJ-tetra-phyllicine or its Z-configurated isomer were not hydroxylated... 

Alkaloids generally are not present in nonflowering plants. It has been suggested that the rise and diversification of this group of compounds is a result of coevolution with mammals. Alkaloids taste bitter to most mammals many of these animals avoid food plants with high alkaloid content (Swain, 1977). As reptiles cannot detect alkaloids as well as mammals (they are about 30 times less sensitive), it was suggested that alkaloids may have had an important role in the demise of dinosaurs (Swain, 1977). The status of this idea must be revised, as dinosaurs now are considered more closely related to birds than reptiles, and the demise of dinosaurs appears to be linked to the collision of a large meteor with the earth. 

Hybrids of Datura ferox [virus susceptible and hyoscine (23) producing] and D. stramonium [virus resistant and hyoscyamine (18) producing] produced vigorous virus-resistant plants that produced hyoscine, an alkaloid important in medicine. The Fi plants inherited the high alkaloid level of D. stramonium, but the oxidative ability of D. ferox. The segregation ratio in the F2 generation is 3 1 and hyoscine production is dominant (Waller and Nowacki, 1978). 

One of the factors that may affect seed alkaloids content is soil nutrient deficiency. For example, K deficiency may induce high alkaloid contents in seeds both of sweet and bitter varieties, while it seems not to affect alkaloid production in the vegetative portions of the plant [33]. 

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