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Phenoloids with allelopathic effect (juglone, ctaechin, tannin, gallic acid t-cinnamic acid, caffeic acid, coumarin, thymol, salicin in 1mM concentration) cannot be detected after the absorption from the acceptor plant (bean) by the applied selective analytical method (TLC densitometry). Their localisation can be determined by histochemical reagens (ferrichloride, potassium bichromate, sodium hydroxide). In the foliage leaves and excised bean plants they are present mainly in the parenchymatuos elements of the vascular tissue already on the 3rd day, at the beginning of wilting.             Some substances (tropanes) out of the studied allelopathic alkaloids (atropine, scopolamine, belladonnin, tropine and caffeine) can be detected only in small amounts (7-8%) or only in traces in the leaf. Others (e.g. caffeine) accumulate in substantial amount (almost 200%) in their original form. Alkaloids,as well as phenoloids, can be detected in lesf tissue by histochemical methods (Dragendorff and Meyer reagents).

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Bending, twitching and quivering are different types of tentacle movements observed during olfactory orientation of the snail. Three recently discovered special muscles, spanning along the length of superior tentacles from the tip to the base, seem to be responsible for the execution of these movements. In this study we have investigated the ultrastructure, contractile properties and protein composition of these muscles. Our ultrastructural studies show that smooth muscle fibers are loosely embedded in a collagen matrix and they are coupled with long sarcolemma protrusions. The muscle fibers apparently lack organized SR and transverse tubular system. Instead subsarcolemmal vesicles and mitochondria have been shown to be possible Ca2+ pools for contraction. It was shown that external Ca2+ is required for contraction elicited by high (40 mM) K+ or 10−4 M ACh. Caffeine (5 mM) induced contraction in Ca2+-free solution suggesting the presence of a substantial intracellular Ca2+ pool. High-resolution electrophoretic analysis of columellar and tentacular muscles did not reveal differences in major contractile proteins, such as actin, myosin and paramyosin. Differences were observed however in several bands representing presumably regulatory enzymes. It is concluded that, the ultrastructural, biochemical and contractile properties of the string muscles support their special physiological function.

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., Kumari, D., Freedman, J., Freedman, N. Chou, C. H. (1986): Caffeine autotoxicity in Coffea arabica. In: Putnam, A. R. Tang, C. S. (eds): The science of allelopathy. John Willey and Sons, N. Y., pp. 243

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Muller, W. C., Greenwood, A. D. (1978) The ultrastructure of phenolic — strong cells fixed with caffeine. J. Exper. Bot. 110 , 757–764. Greenwood A. D. The ultrastructure of phenolic

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. , da Conceição , R. R. , da Silva-Almeida , C. , Marinho , B. G. , da Rocha , F. F. , Reis , L. C. , Côrtes W da , S. ( 2016 ) Behavioral profile assessment in offspring of Swiss mice treated during pregnancy and lactation with caffeine

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