Ricin ricinine

N.A. Ricinoleic acid, ricin, ricinine, lectins.99 The seeds are toxic. Laxative, prompting a bowel movement. 

Waller, G.R., Negi, S.S. (1958). Isolation of ricin, ricinine, and the allergenic fraction from castor seed pomace from two different sources. J. Am. Oil Chem. Soc. 35 409-12. 

CDC Case Definition A clinically compatible case with (1) detection of urinary ricinine, an alkaloid in the castor bean plant or (2) detection of ricin in environmental samples. The case can be confirmed if laboratory testing is not performed because either a predominant amount of clinical and nonspecific laboratory evidence is present or an absolute certainty of the etiology of the agent is known. 

Nicotinic acid undoubtedly provides the basic skeleton for some other alkaloids. Ricinine (Figure 6.35) is a 2-pyridone structure and contains a nitrile grouping, probably formed by dehydration of a nicotinamide derivative. This alkaloid is a toxic constituent of castor oil seeds (Ricinus communis Euphorbiaceae), though the toxicity of the seeds results mainly from the polypeptide ricin (see page 434). Arecoline (Figure 6.36) is found in Betel nuts (Areca catechu Palmae/Arecaceae) and is a tetrahydronicotinic acid derivative. Betel nuts are chewed in India and Asia for the stimulant effect of arecoline. 

Extracts from the castor bean can be used to isolate ricin, an extremely potent poison that is one of the leading candidates for use by terrorists. Ricin is a large-molecule, heterogeneous protein. A chemical marker for ricin is the hydrolysis product alkaloid ricinine, shown in Figure 19.2. 

S.M. Darby, M.L. Miller and R.O. Allen, Forensic determination of ricin and the alkaloid marker ricinine from castor bean extracts, 7. Forens. Sci., 46, 1033-1042 (2001). 

Mouser, P., Filigenzi, M.S., Puschner, B. et al. (2007). Fatal ricin toxicosis in a puppy confirmed by liquid chromatography/mass spectrometry when using ricinine as a marker. J. Vet. Diagn. Invest 19 216-20. 

In cases where the toxin is metabolized, excreted, or otherwise not available for immunological or chemical detection, it may be possible to verify an exposure to ricin or castor seeds for forensic purposes by detecting other unique components of the R. communis plant. PCR can detect residual castor seed DNA in most ricin preparations. Ricinine, an alkaloid (3-cyano-4-rnethoxy-A -rnethyl-2-pyridone) produced by castor seeds, has been proposed as a biomarker for ricin exposure the detection limit for ricinine by electrospray ionization tandem mass spectrometry is as low as 0.083 ng/mL in urine of exposed subjects (Johnson et al., 2005). 

Quantification of ricinine in rat and human urine a hiomarker for ricin exposure. J Anal Toxicol, 29,... 

The cake remaining after mashing, crushing, or solvent extraction of the oil is known variously as castor pomace, castor flake, castor meal, or poonac. It contains ricin, a highly toxic protein ricinine, a toxic alkaloid and CB-IA, an extremely potent allergen. The cake with its high potassium, fibre, and protein concentration is used as a fertilizer and as animal feed after detoxification. 

Castor oH (ricinus oil). The oil obtained from seeds of the castor-oil plant or castor beans (Ricinus communis, Euphorbiaceae), mp. -10 C. It contains about 80-85% ricinoleic acid as glycerol ester together with oleic (7%), linolic (3%), palmitic (2%), and stearic (1%) acids. The Ricinus seeds contain the highly poisonous constituents ricin, a mixture of proteins, and ricinine, a pyridone alkaloid. The presence of these substances leaves the oilcake remaining after pressing of C. unsuitable for use as animal fodder. 

Castor oil is not toxic it contains neither ricin nor ricinin (Fig. 3.34), which are insoluble in the oil. Most of castor oil is glycerol triricinoleate. Digestive enzymes (lipases) in the intestine break down this molecule into glycerol and ricinoleic acid, and the latter possesses a laxative effect. Despite the fact that the use of castor oil in case of constipation dates back centuries, the mechanism of the action is not fully imderstood yet. About 5-10 g of castor oil is usually quite efficient with the onset of the action after 6-8 h. A larger dose may do its job within a shorter time. Despite certain jokes, the effect is never instantaneous. 

The oil is isolated by pressing and solvent extraction. The first pressing yields No. 1 oil (USA), a virtually colourless oil (free fatty acid 2%) suitable for medicinal use. The residual meal contains three toxins ricinine, a mildly toxic alkaloid, ricin, an extremely poisonous protein, and a heat-stable allergen which forms approximately 12% of the cake. The seed also contains a very active lipase. 

A recent report described MALDI-TOF MS characterization of ricin, an extremely potent poison from the seeds of the castor bean plant. Ricin has been mentioned in terrorism literature and was reportedly used in a high profile international spy homicide case. In the MS application, samples were first purified by LC fractionation or molecular weight cutoff filtration. Confirmation was carried out by comparing the MALDI-TOF MS spectrum of the tryptic digest against a standard and GC-MS identification of an alkaloid marker, ricinine. 

Ricinine is not markedly toxic the poisonous character of castor-oil seeds is due to a more complex substance, ricin, the activity of which can be destroyed by heat. 

Analytical methods used to idenhfy ricin include immxme methods (ELISA) and liquid chromatography/ mass spectrometry (LC/MS). Gastric contents can be assayed and ricin can be detected in blood and body fluids by radioimmunoassay and LC/MS (Darby et al., 2001 Mouser et al., 2007). Ricinine levels can be assayed in serum and urine using LC/MS (Roen et al., 2013). Polymerase chain reaction methods are available to detect the DNA in castor beans. 

Roen, B.T, Opstad, A.M., Haavind, A., et ah, 2013. Serial ricinine levels in serum and urine after ricin intoxication. J. Appl. Toxicol. 37, 313-317. 

Methods for indirect detection of ricin analyzed samples for components that are present in castor seed extracts, in particular castor DNA and the alkaloid ricinine (Fig. 4.3). These approaches were concerned with crude ricin preparations as described in a terrorist handbook (Darby et al., 2001). Although ricin is not a major component of these crude preparations, they do pose some threat and represent a concern due to their description in such a handbook. 

The alkaloid ricinine is present throughout the castor plant from the time of early germination to seed maturation (Waller and Nakazawa, 1963). It has been used as an indirect means for detecting ricin in crude ricin preparations (Darby et al., 2001), but is more commonly used to detect ricin poisoning (eg, Hamelin et al., 2012), as it is eliminated from the body in urine and is readily identified byGC/MSorLC/MS. 

The seed contains 40-50% oil (- -castor oil) with 14-22% crude protein, 15-18% crude fiber, and 2-3% ash. Important for further use of the protein are two types of -+alkaloids 0.03-0.15% ricinin and about 3% ricin, the toxicity of which is higher than that of potassium cyanide. This means that, after oil -> expelling and -> extraction, the residue is not to be used for any feeding purposes, unless it is treated further to destroy toxic and allergenic substances. It may, however, be used as fertilizer. There are also recent genetic efforts (Costa Rica, Europe, USA) to increase oil content and quality and to reduce the toxic effects of the plant and seeds. Lit D.Atsmon Castor in Rdbbelen 438-448 (1989) Rehm/Espig (1991)... 

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