Potatoes, sprouting

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). 

Two pheromonal components were detected in airborne collections from the vine mealybug, Planococcus ficus Signoret (Hemiptera Pseudococci dae) in Israel. They were identified as (5 )-lavandulyl senecioate (1) and (5)-lavandulyl isovalerate (II). Compound I has been identified as the sex pheromone of P. ficus in California. The report shows that feral P. ficus mealybugs produce and respond only to (I) whereas mealybugs reared in the laboratory on potato sprouts produce and respond to both (I) and (II). 

Kozukue, N., Tsuchida, H., Friedman, M. (2001). Tracer studies on the incorporation of [2-14C]-DL-mevalonate into chlorophylls a and b, a-chaconine, and a-solanine of potato sprouts. J. Agric. Food Chem., 49, 92-91. 

Daniels-Lake, B and Barnes, J. (2007). Current Methods and Reeent Trends In Potato Sprout Control Around the World. International potato processing and storage eonvention, October 10-12, Calgary, Alberta, Canada. 

Lewis, M. D., Kleinkopf, G. E., Shetty, K. K. (1997). Dimethylnaphthalene and diisopropylnaphthalene for potato sprout control in storage 1 Application methodology and efficacy. American Potato Journal, 74, 183-197. 

Elmer, O.H. (1932). Growth inhibition of potato sprouts by volatile products of apples. Science 75,193. 

Solanidine-GTase was purified to near homogeneity from potato sprouts. The isolation of this enzyme was complicated by its copurification with patatin. Separation of the two proteins was finally achieved by binding the glycosylated patatin to concanavalin A, under conditions where the solanidine-GTase did not bind. In this study, no enzyme activity was detected... 

Irradiation. Ionizing radiation for use in food systems can come from electrons, x-rays, or gamma rays from cobalt-60 or cesium-137. There is little rise in the temperature within the foodstuff, so heat destruction of nutrients is minimized. However, free radicals and peroxides are formed within the food. In the United States, irradiation is classified as a food additive and its use in the food industry has been severely restricted to such areas as prevention of potato sprouting and wheat infestation. 

Cizkova, EL, Vacek, J., Voldrich, M., Sevcik, R. and Kratka, J. (2000). Caraway essential oil as potential inhibitor of potato sprouting. Rostlinna Vyroha, 46 (11) 501-507. 

Arle, Leonard, and Harris80 reported the use of activated carbon to protect sensitive field crops against injury from a weed killer— 2,4-D (2,4-dichlorophenoxyacetic acid). In one of several experiments, a field was sprayed with 2,4-D—1.3 pounds free acid equivalent per acre. One-half of the plot was planted with sweet-potato sprouts that had been previously moistened and then dusted with activated carbon the other half of the plot was planted with untreated sprouts. In the case of the untreated sprouts, only 2.5% survived whereas 95.0 % of the sprouts treated with activated carbon survived and produced plants that were normal in every respect. Weaver81 found that the toxic effect of 2,4-D on soybean, red kidney bean, white mustard, or marigold were eliminated or decreased by dusting or spraying activated carbon in aqueous suspension on the plants before the 2,4-D treatment. 

Isolation. The fresh crushed potato sprouts are allowed to remain for 4S hours with twice their weight of 2% acetic acid. The acid solution is separated with the aid of a centrifuge, filtered with a little celite, and rendered distinctly alkaline by the addition of ammonia. After 24 hours the precipitate is separated by filtration, washed, and dried. The admixed solanidine is separated by exhaustive ether extraction and may be obtained in impure form by evaporation of the ether. The ether-insoluble portion is extracted with hot 80% ethanol and, upon concentrating and cooling the extract, the crude solanine separates. It may be recrystallized from 80% ethanol or from dioxane (39, 56). As thus purified it melts at 285° and has [a]D — 42 (dilute hydrochloric acid), —56.5° (pyridine), —60° (pyridine) (31, 62). 

Solanine and chaconine are probably the most widely consumed natural toxins in North America. These alkaloids are colorless, but their production parallels the production of chlorophyll — which, of course, is green. That s why green potatoes are suspect. Sometimes, when their concentration is high enough, solanine and chaconine will make your tongue burn. Potato sprouts are rife with alkaloids, so you should always cut them off. 

A patent on a new class of sprout suppressants was published recently [35]. It covers trans-2-ketones and trans-2-aldehydes (Fig. 11.6) being active as potato sprout suppressants. Known from grass smell, trans-2-hexenal is included in this patent. 

The causal fungus of Fusarium wilt of sweet potato is Fusarium oxy-sporum f sp, betatas. Some isolates of F, oxysporum which are obtained from healthy sweet potato plants showed remarkable crossprotection against the disease, when they were previously inoculated in the sweet potato sprouts before being planted in the infested soil. These isolates of F. oxysporum were not pathogenic to sweet potato, and also not to other plants such as tomato, cucumber etc. 

Uses Herbicide plant growth regulator potato sprouting inhibitor... 

Oosterhaven, K., K.J. Hartmans, and J.J.C. Scheffer, 1995a. Inhibition of potato sprouts growth by carvone enantiomers and their bioconversion in sprouts. Potato Res.. 38 219-230. 

Oosterhaven, K., B. Poolman, and E.J. Smid, 1995b. 5-Carvone as a natural potato sprouts inhibiting, fungistatic and bacteriostatic compound. Indian Crops Prod.. 4 23-31. 

Oosterhaven K, Poohnan B, Smid EJ (1995) S-Carvone as a natural potato sprout inhibiting, fungistatic and bacteristatic compound. Ind Crop Prod 4 23... 

A similar trisaccharide composed of two D-glucose units and one d-fructose unit can be isolated by charcoal chromatography from the honey-dew of the citrus mealy bug Pseudococcus citri when feeding on the sap of potato sprouts 207). Presumably this trisaccharide arises as a natural product in the digestive systems of many insects. Also there is chromatographic evidence for its presence in honeydews of cottonlike maple scale, Pulvinaria vitis, and in the spirea aphid, Aphio spiralcola. 

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