Solanum species, alkaloids

Among the well-known Solanum species that have been chemically examined are S. nigrum, S. tuberosum (potato) and S. lycopersicum (tomato). From these and other species an alkaloidal glucoside, which was first prepared by Desfosses, has been obtained. This substance has been named solan ine, but it is not certain that all the plants recorded as containing solanine contain the same solanine or that the alkaloid has been obtained in a pure state in each case. 

The potato beetle (Leptinotarsa decemlineata) lives on Solanum species containing steroid alkaloids, which are tolerated, but not stored, by this species. The bruchid beetle Callosobruchus fasciatus predates... 

Fig. 2 TLC-immunostainings of steroidal alkaloid glycosides in the crude extracts of Solanum species fruits. Crude extracts were developed by a CHCl3-Me0H-NH40H solvent system on silica gel TLC plate. After being transferred to a PVDF membrane, the membrane was treated with NaI04 and stained by MAb. Spots 1-3 were identified with khasianine, solamargine, and solasonine, respectively.

The inheritance of alkaloids in Cinchona species has been the subject of an extensive program (230). If two Solanum species containing demis-sine and solanine, respectively, are hybridized a plant results which elaborates both alkaloids (231). 

Many Solanum species contain alkaloidal glycosides which on removal of the sugar residue by hydrolysis yield alkamines with 27 carbon atoms. A number of the same alkamines have been also isolated along with their glycosides, but since no particular precautions to prevent enzymatic hydrolyses have been taken, it is not always certain that the alkamines are primary plant constituents. The alkamine solanocapsine has only been found as such, and it has not been possible to isolate its glycoside even under conditions designed to circumvent its hydrolysis. 

A comprehensive survey of the solasodine content of 85 native Australian Solanum species has been published. Several studies have appeared which describe the changes in distribution and concentration of solasodine during the Ufe cycle of S. laciniatum. The effects of light colour on the solasodine content of 5. laciniatum and on the solasodine content of clones of 5. dulcamara have been studied the effect of ecological factors on alkaloid production by these two species has also been investigated. The solasodine contents of developing berries,fruits, and seed callus of S. khasianum have been reported. 

Glyco-alkaloids are responsible, at least in part, for the resistance of several other species to various agricultural pests. A t.l.c. system for the quantitative determination of potato glyco-alkaloids has been reported. The enzymic hydrolysis of a-chaconine and a-solanine and the hydrolysis of solanine by the potato blight fungus, Phytophthora infestans, ° have been studied. Techniques for studying the alkaloids of Solanum species have been reviewed. ... 

A series of polyhydroxylated tropane alkaloids have been isolated from the leaves of Solanum tuberosum and from both a sphingid moth and an ithomiine butterfly, the larvae of which feed on Solanum species (Nash et al., 1993). These alkaloids are potent glycosidase inhibitors, in a manner similar to certain hydrox3q)yrrolidine and indolizidine alkaloids see Chapter 30). 

Glycoalkaloids appear to be synthesized in aereal portions of Solanum species and not in roots, as in the case of tropane alkaloids of many solanaceous species (Waller and Nowacki, 1978). 

As mentioned above, demissine and several other steroid alkaloids are repellent or toxic to the Colorado potato beetle. Races of this insect are adapted to several Solanum species, including S. eleagnifolium, S. rostratum, and 5. tuberosum, and the insect has a recognized ability to adapt to new combinations of steroid alkaloids (Harbome, 1986). 

Solasodine see a-Solasonine. a-Solasonine, solasonine a Solanum steroid alkaloid occurring in many species of Solanum, e.g. S. sodomeum, S. aviculare, S. laciniatum and X nigrum. It is a glycoalkaloid containing the aglycon, salaso-dine [(22R 25R)-spirosol-5-ene-3p-ol], M, 413.67, m.p. 201 °C, [aJo -107° (CHCI3) and a branched trisaccharide. 

Solanum steroid alkaloids have been isolated so far from nearly 350 species of the plant families Solanaceae and Liliaceae, in which they generally occur as glycosides. All of the 75 known steroidal alkamines of the Solanum type,... 

Nitrogen-Free Steroid Sapogenins (Spirostanou) and Related Compounds in Solanum Species and Other Plants Containing C27-STER01D Alkaloids ... 

Solanidine and demissidine can be separated on a silver nitrate-impregnated silica gel layer. Schbeibeb et al. [207 b] have used TLC also for preparative separation of Solanum alkaloids. Using 8 solvents on silica gel G layers, Paqijin and Lepage [158] have separated the three principal alkaloids from Solanum tuberosum, i. e., solanine, chaconine and solanidine. Antimony(III) chloride reagent was used for visualisation. P bez-Medina et al. [164] have investigated many Solanum species in the search for a raw material source of solasodine. They used TLC on silica gel 6 with n-butanol-methanol-diethylamine (85 + 5 + 10) as solvent and antimony(III) chloride (Rgt. No. 16) for visualisation. The TLC of this alkaloid class is described in other publications [2, 25, 183, 208]. 

Besides avoiding, some insects can tolerate the defense chenustry of their host. The potato beetle Leptinotarsa decemlineata) lives on Solanum species containing steroidal alkaloids, which are tolerated but not stored by this species. The bruchid beetle, Bruchidius villosus, predates seeds of QA rich plants, such as Laburnum anagyroides. This beetle eliminates most of the dietary cystisine with the faces. Certain aphids can store the dietary alkaloids, for example, QA in Aphis cytisorum, A. genistae, and Macrosiphum albifrons and PA in Aphis jacobaeae and A. cacaliaster [70]. 

Kerber VA, Moreira EA, Gomes EC, Weiss FA, Vieira RF (1993) Qualitative and quantitative evaluation of steroidal alkaloids in three Solanum species - (S. grandifolium, S. lacerdae, and S. lycocarpum) with reference to solasodine. Rev Brasil Farm 74 67-69 Kereselidze EV, Pkheidze TA, Kemertelidze EP (1970) Steroid sapogenins from Cestmm elegans and Cestmmparqui. Khim Prir Soedin 6 379... 

On the other hand, the steroid sapogenins nearly always seem to accompany the cholestane alkaloids, thus demonstrating the close structural and biogenetie relationship between both groups of natural products. Section V of this chapter contains a tabulated survey of all steroid sapogenins so far isolated from Solanum species and other cholestane alkaloid-containing plants. 

Table VII lists the steroid sapogenins CDXXX-CDXLIII found in Solanum species and other Solanaceae containing steroid alkaloids. In...

Occurrence or Steroid Sapogenins (Spirostanols) in Solanum Species and Other Solanaoeae Containing Steroid Alkaloids... 

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