Solanine

Many studies have reported a link between consumption of sunburned potatoes, ie, those exposed to the sun and having an accumulation of chlorophyll and solanine under the skin, with incidences of teratogenic effects and even death (59—61). Because sunburned potatoes in the commercial marketplace are relatively rare, and because the long-term effects of consumption of potatoes at the maximum estabUshed limits of solanine concentration are uncertain, there is equal uncertainty of the tme incidence of human toxicity (62). 

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. 

Firbas stated that at least two of these alkaloidal glucosides occur in young potato shoots, solanine and solaneine, and that these may be accompanied by solanidine, a basic decomposition product of solanine. Solaneine was later shown to be a mixture of solanine and solanidine. 

The name solanine should be sufficient to indicate that the substance referred to is the glucosidal alkaloid first isolated from potatoes. The use of such forms as T-solanine, solanine-t and solanine tuberosum is confusing, as is also the proposed substitution of solatubine for solanine. 

Solaneine, isolated by Firbas and examined by Davis, has been shown by Soltys to be a mixture of solanine and solanidine. 

Colour Reactions. Rochelmeyer (1939) has provided a list of colour reactions given by solasodine and solasodiene (solanosodine), with reagents usually applied to the sterols, and Briggs et al. have found that when concentrated sulphuric acid (1 mil) is carefully added to a solution of solasonine or solasodine in hot alcohol (1 mil) a characteristic, intense, greenish-yellow fluorescence is produced, a reaction which is not given by solanine or solanidine. They have also found that intense colours are formed when solasonine or solasodine is mixed with resorcinol, or one of a variety of aldehydes, and boiled with concentrated hydrochloric acid. Colours are also produced with this test by cholesterol, digitonin, jacobine carbazole, pyrrole, or nicotine, the most intense colours being formed with p-hydroxybenzaldehyde or anisaldehyde. 

Solangustidine solangustine, 671 Solanidine, 661, 662, 671, 708, 712, 713 dehydrogenation products, 663 heterocyclic residue, 665 proximate derivatives, 664 structure, 665, 667 Solanine, 661... 

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. 

Air, water, soil, and food are all unavoidable components of the human environment. Each of those elements influences the quality of human life, and each of them may be contaminated. Food is not only the elementary source of nutrients, but may also contain natural chemical substances with toxic properties, e.g., cyanogenic glycosides (many plants), solanine (green parts of potatoes, sprouted potatoes, and potatoes stored in light), industrial pollutants (heavy metals), biogenic amines (fish), or mycotoxins (moldy foodstuffs). 

The structural features of the solanum alkaloids are based on two primary skeletal configurations solanidane, with or without glycoside functionalities, as featured by the toxic and teratogenic steroidal alkaloids a-chaconine and a-solanine with the indolizidine type E-F ring (Figure 2.7a) and the spirosolane... 

Lift and leave exposed to dry for a few hours. Store in thick paper sacks, tied or folded loosely at the neck. Potatoes must be stored in the dark to prevent them from turning green and developing high levels of solanine, a toxic alkaloid. Frost protection is essential. Ideal storage temperature is 41-50°F (5-10°C). 

Weltring KM et al (1997) Metabohsm of potato saponins a-solanine and a-chaconine by Gibberella pulicaris. Phytochemistry 46 1005... 

Glycosides of compounds with a triterpenoid origin include saponins, cardiac glycosides, and glycoalkaloids such as solanine (in potatoes). 

Solanine (Fig. 11.8) occurs in potatoes, particularly in peel (to 1.5 mm depth), eyes, and repaired tissue, and in small and immature, and light-exposed... 

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