Potatoes, solanum alkaloids

The fruit of a number of solanaceous plants, including tomato Lycopersicon esculentum), potato Solanum tuberosum) and eggplant Solarium melongena esculentum), have cholinesterase-inhibiting effects (Krasowski et al. 1997). They contain solanaceous glycoalkaloids o-solanine and o-chaconine, which are triglycosides of solanidine, a steroidal alkaloid derived from cholesterol. They are the only plant chemicals known to inhibit both acetlycholinesterase and butyrylcholinesterase, both in vitro and in vivo. 

Alkaloids are active bioagents in animal tissues. There is clear scientific evidence of this. Crawford and Kocan" " have tested the toxicity of steroidal alkaloids from the potato Solanum tuberosum), such as a-chaconine, a-solanine, solanidine and solasodine, and Veratrum alkaloid, jervine on fish. The results of Crawford and Kocan s research proved that rainbow trout exhibited a toxic response to chaconine, solasidine and solanine, while medaka only did so to chaconine and solanine. Embryo mortality was observed as an effect of toxicity in both species. Many other alkaloids are known to disturb or cause disorder in animal reproductive systems. For example, gossypol from cotton-seed oil is known as a clear reducer of spermatogenesis and premature abortion of the embryo. 

Chromatographic analysis of glycoalkaloids can be performed in a number of ways (321,322). The intact compounds can be analyzed by GC after derivatization (323). After hydrolysis the aglycone skeleton can be examined by GC without the need of derivatization (324). For routine determinations of the glycoalkaloids present in potato tubers, HPLC is probably the method of choice. Column acidity caused by active silanol sites on the packing surface strongly influences the chromatographic separation of Solanum alkaloids. In fact, basic compounds react with... 

The mass-spectral fragmentation of solasodine has been discussed.49 A g.I.c. method has been described for the analysis of potato glyco-alkaloids.50 A study has been reported on the separation of Solanum and Veratrum alkaloids by h.p.l.c.51... 

Potato alkaloids. The cultivated potato (Solanum tuberosum L.) contains two major glycoalkaloids, a-chaconine and a-solanine. The two components both contain the C i steroidal aglycone solanidine they differ only in the sugar moieties included in the trisaccharide part. a-Solanine and a-chaconine form up to 95% of the glycoalkaloids present in potatoes. Data on occurrence, chemistry, analysis, and toxicology of the steroidal glycoalkaloids present in potatoes have been comprehensively reviewed (77, 75). 

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. ... 

The toxic alkaloid solanine, having a steroidal skeleton, is present in the sprouts of potato Solanum tuberosum) of the Solanaceae [1]. Subsequently, it was determined that the solanine is a mixture that could be separated... 

Biological Activity of Solanum Alkaloids Solanum Alkaloids in Potatoes Teratogenic Properties Veratrum Alkaloids Biosynthesis Biological Activity... 

Solanidine see a-Solanine. o-Solanine, solanine a Solanum alkaloid, the chief toxic alkaloid of the potato (Solanum tuberosum), also present in other Solanum spp. It is a glycoalkaloid containing the aglycon solanidine (sola-nid-5-ene-3p-ol), M, 397.65, m.p. 218°C, [aJo -27° (CHCI3), and the trisaccharide p-solatriose (Fig.). Potato tubers contain no more than 0.01 % a-S., which is harmless in this quantity. Potato shoots contain 0.5 % c(. and therefore cannot be used as food. 

A subgroup of the steroidal saponins are the glycoalkaloids, in which the aglycone is a steroidal alkaloid (contains a nitrogen atom). The most common source of these compounds is the Solanum genus, including the common potato Solanum tuberosum. 

The solanum alkaloids occurring in species of Solarium, including potatoes, Dead Sea Apple, and poro-poro, also contain the steroid nucleus... 

We are now aware of just how complex is the mixture of chemicals present in food. For example, for the common potato (Solanum tuberosum), besides many substances of known nutritional value, about 120 additional substances have been detected, including solanine alkaloids, oxalic acid, arsenic, etc. An additional 228 chemicals have been identified in potatoes roasted in their skins. Naturally occurring chemicals in food have been associated not only with acute toxicity, but also with cancer and other chronic diseases (11). 

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. 

In the Andes, nearly all of the about 160 varieties of wild potatoes, and two of the eight cultivated species are toxic. Some frost-resistant species that grow above 3600 m have high levels of alkaloids, which are bitter and potentially toxic. These are hybrids between Solanum stenotonum and wild potatoes such as Solanum megistacrolohum and Solanum acaulc. Other secondary plant compounds in potatoes are saponins, phytohemagglutinin, proteinase inhibitors, sesquiterpene phytoalexins, and phenols. 

Solanum tuberosum L. Vitamins A, B1 B2, C, and K, minerals, atropine alkaloids.99 Potato juice treats peptic ulcers, relieve pain and acidity. 

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... 

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