Cocculus

COKUL'VAN, or kokul'van, or fish berries (Fructus Cocculi, Cocculi indici seu piscatorii, Grana Cocculi, Baccae orientales), fruits of the dioecious, highly climbing woody liana Anamirta cocculus Wight et Arnott, Anamirta panicuiata, Menispermum Cocculus L. (family Menisperma-ceae). The homeland of C. is Ceylon, Indonesia, the Molucca Islands. The commercial product consists of dry, grayish-brown, wrinkled, kidney-shaped spherical fruits, 10-12 mm in length and 7-9 mm in width, having in longitudinal section the shape of a crescent. The shells and other parts of the fruit walls have no taste or smell, whereas the seeds, on the contrary, possess a disagreeably bitter taste of picrotoxin, to which C. owes its poisonous properties. Besides picrotoxin, anamirtin, or kokkul'lin, C₁₉H₂₈O₁₀ (tasteless, needle-shaped crystals), is found in the seed tissue, and in the fruit tissue - menispermin, C₁₈H₂₁O₂N₂ and paramenispermin; both are non-poisonous. Furthermore, C. contains fatty oil (11-24%) of a semi-solid consistency and free stearic acid. Picrotoxin C₃₀H₃₄O₁₃, a non-nitrogenous toxin, is contained up to 1.5% in the endosperm of the seed, has a neutral reaction, melts at 199-200°, is difficultly soluble in cold water, easily in hot water, in alcohol, chloroform, amyl alcohol, acetic acid, caustic alkalis, and ammonia. It behaves as a weak acid towards strong bases, which is why it has the synonym picrotoxinic acid; it relatively easily splits up into picrotoxin, C₁₅H₁₆O₆ (melts at 200-201°), and picrin, C₁₅H₁₈O₇ (melts at 249°). Picrotoxin belongs to the number of convulsive poisons; it acts primarily on the centers of the medulla oblongata, first exciting and then paralyzing. Reflexes under picrotoxin are heightened owing to the excitation of the spinal cord, but in contrast to strychnine, differences in the reaction to mechanical and chemical irritations are not observed here. In medicine, picrotoxin is no longer applied; previously it was applied in the therapy of heart afflictions, in some forms of paralysis, in chorea and hysteria-epilepsy, but unsuccessfully. Besides, C. was previously applied for the extermination of lice and in ointments for skin diseases of the head, but due to its poisonous nature it has been completely abandoned. At present, C. has mainly a toxicological significance as a poison applied for catching fish [fish poisoning by C. in a mixture with flour dough; fish become stunned and float to the surface, where they are collected (a forbidden method)], and as a bitter substance (instead of hops) in beer production. In both these cases, the application of C. causes poisoning of consumers (by fish meat or beer), which is why the application and the import of C. into the USSR has long been prohibited. Poisoning by C. is characterized in the initial stage by strong pains and burning in the esophagus and stomach, as well as vomiting and diarrhea; then symptoms on the part of the central nervous system appear: characteristic swimming clonic convulsions, alternating with tonic ones, accompanied by periodic cessation of respiratory movements of the diaphragm and slowing of the heartbeat. Treatment in poisoning by C. is symptomatic: washing out the stomach, internally chloral hydrate, phenobarbital, lobeline up to 0.005; morphine and tobacco enemas are less reliable; tannin is useless. In forensic-chemical cases, picrotoxin is extracted from an acidic or neutral (but not alkaline) medium by ether and chloroform, and the residue after evaporation of the solvent is tested with reagents. Reactions to picrotoxin. 1. Concentrated sulfuric acid dissolves picrotoxin with an orange coloring, which changes from the addition of traces of potassium dichromate to violet, and from excess to a brown color. 2. A mixture of picrotoxin with three parts of nitre, moistened with concentrated sulfuric acid, from the addition of excess of a strong solution of caustic soda is colored brick-red (Langley's reaction), soon disappearing. 3. A good physiological test on small fish, which float to the surface of the water, poisoned by C., with open mouths and gills, having lost the ability to regulate the volume of the swim bladder, is also good. 4. Traces of picrotoxin with one drop of a 20% alcoholic solution, benzaldehyde, and one drop of concentrated sulfuric acid without stirring give a carmine-red coloring (a similar reaction is given by cholesterol).