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Tropical and Subtropical Agroecosystems, 1 (2003): 295 - 307 INDOLEALKYLAMINES IN MUCUNA SPECIES
N. J. Szabo
Tropical and
Analytical Toxicology Core Laboratory, Center for Environmental and Human Toxicology, University of Florida, P.O.Box 110885, Gainesville, FL 32611-0885, USA E-mail: [email protected] (n=15), concentrations averaged 3.46, 3.09, and 1.48 µg g-1, respectively. As expected, 5-methoxy- Before Mucuna can be widely promoted as a food and dimethyltryptamine was quantified in all samples. In feed crop, the presence of antinutritional components root and pod, concentrations of 1.76 and 1.29 µg g-1, and their potential long-term effects must be respectively, were found, with average levels of 1.44, appraised. In addition to L-dopa, a number of indolic 1.48, and 0.64 µg g-1 present in leaf (n=5), stem (n=5), alkaloids structurally related to serotonin have been and seed (n=15), respectively. Compared to L-dopa, reported in various parts of the Mucuna plant. Several the detected indoles were present at roughly 0.0001% of these naturally occurring compounds, all of which by weight, lower than had been previously estimated. share tryptamine as a base structure, are known to While ordinary cooking and storage conditions would have hallucinogenic properties of considerable not be expected to affect the stability of these strength. In this study, five related alkaloids components, preparation approaches that effectively (tryptamine, serotonin, N,N-dimethyltryptamine, 5- decrease L-dopa (like boiling) should decrease even methoxy-dimethyltryptamine, and bufotenine) were further the concentrations of these antinutritional assayed in the tissue and/or seed samples of twenty components. It would be unlikely for these low-level Mucuna accessions by liquid chromatography with alkaloids to have any effect on human and animal mass spectral detection. Samples included the roots, consumers, especially as absorption across the stems, leaves, and pods of dried plants, the stems and gastrointestinal tract is negligible. Serotonin, for leaves of fresh-frozen plant material, and raw seeds. instance, is known to be present in common fruits In a previous screening study, 5-methoxy- (bananas and pineapples) at levels ten to twenty times dimethyltryptamine had been confirmed in each of the alkaloid concentrations found in Mucuna tissues, several samples examined, with serotonin and yet these are considered safe for human and animal tryptamine found in only a few select samples. The consumption. In fact, most tryptamine derivatives are concentrations of these components were estimated to characterized by poor absorption, rapid peripheral be 0.001%, low compared to that of L-dopa (4-7% metabolism, and for these reasons have little or no by weight in raw seed), but of concern nonetheless. In recognized oral activity unless ingested in the presence the current quantitative study, neither tryptamine nor of an oxidase inhibitor. Thus, the presence of low N,N-dimethyltryptamine were detected in any sample level indolealkylamines is unlikely to affect the (<0.50 µg g-1), although ions corresponding to potential use of Mucuna as a staple crop, providing tryptamine were noted periodically as fragmentation valuable protein sources for food and feed. products for several of the other compounds, especially serotonin and bufotenine. An unknown Key words: Bufotenine, indolealkylamine, Mucuna,
compound close to the weight of serotonin, possibly serotonin, tryptamine. N-methyltryptamine, was determined in all plant tissue samples and one seed sample. Although serotonin was not present in any sample tested (<0.50 µg g-1), the levels of the unknown indole were estimated against The major drawback of Mucuna spp. which has the serotonin standards. In root and pod, 5.96 and compromised its usefulness as a food source for either 4.03 µg g-1 were calculated, respectively, with an humans or livestock, is associated with its chemical average of 8.49 and 3.94 µg g-1, respectively, in leaf content. A review of the available, but limited, (n=5) and stem (n=5). Only one seed sample (1.70 µg literature often shows confusing and conflicting data g-1) contained the unknown compound in detectable concerning the chemistry of Mucuna. There is some amounts. Bufotenine was also identified in most difference of opinion among researchers as to the samples; in root at a level of 4.14 µg g-1, but not in the toxicity of this genus, and subsequently, disagreement pod sample. In leaf (n=5), stem (n=4) and raw seed as to the best approach to develop Mucuna into a food hydroxytryptamine). Serotonin, a mammalian neuro- transmitter, has a variety of effects on nerves and smooth muscle, respiration, the heart and In Mucuna seeds, as in the beans of many food grain cardiovascular system, and the gastrointestinal tract. legumes (e.g., common bean and soybean), a large Many plants and insects also produce serotonin; for number of anti-nutritional compounds have been example, it is present in pineapples (17 µg g-1) and identified, including tannins, lectins, phytic acid, bananas (15 µg g-1; Feldman and Lee, 1985), in cyanogenic glycosides (Siddhuraju et al., 1996; stinging nettles (Urtica sp.) and in wasp and scorpion Laurena et al., 1994; Ravindran and Ravindran, 1988), stings. In contact with skin, it causes an intense and trypsin and amylase inhibitors (Siddhuraju et al., burning sensation, inflammation, and itching. 1996). Because these factors are initially low in Although the pods of certain Mucuna cultivars are concentration and are inactivated or further reduced in known to cause severe stinging, it is not certain concentration during cooking (Bressani, 1993), they whether this is due to serotonin, to a protein called will not be considered in this report. Of much greater mucunain (Fairbrothers et al., 1985), or to some other concern has been the presence of L-dopa (3,4- dihydroxy-L-phenylalanine or 3-hydroxy-L-tyrosine; Daxenbichler et al., 1971, 1972; Lorenzetti et al., The purpose of this report is to evaluate the available 1998), a compound used in the treatment of information concerning the chemistry and toxicology Parkinson's disease, and the presence of of indolealkylamines present in Mucuna spp., to hallucinogenic indoles such as N,N-dimethyl- present our own data following chemical analysis of tryptamine, bufotenine and other tryptamines, the roots, stems, leaves, and pods of dried plants, the including serotonin, in various parts of the Mucuna stems and leaves of fresh plant material, and raw seed plant (Ghosal et al., 1971). While recent research has samples, and to evaluate the implications of the new greatly advanced the current state of knowledge on data in the framework of human health effects. issues related to L-dopa (Flores et al., 2002; Myhrman et al., 2002; Szabo and Tebbett, 2002; Eilittä et al., 2002), the indolic alkaloids have been largely ignored. Classical hallucinogens are broadly divided between Of the more than 700,000 plant species identified, indolealkylamines and phenylalkylamines. The fewer than 100 were recognized to contain compounds indolealkylamine category consists of tryptamine of psychoactive or hallucinogenic potential in the derivatives (such as DMT, 5-MeODMT, bufotenine, 1980's (Siegel, 1984). Whether or not Mucuna should psilocybin), the ergolines or lysergic acid derivatives be included in this group has been uncertain; reports (lysergide or LSD), and the β–carbolines (such as having been contradictory. Serotonin, bufotenine, ibogaine and the harmala alkaloids). The phenyl- N,N-dimethyltryptamine and other unidentified indoles alkylamine category includes phenylethylamines, such were first described by Ghosal et al. (1971) as present as mescaline (e.g., peyote), and phenyl- in the pods, seeds, leaves and roots of M. pruriens. isopropylamines, such as the amphetamine Compound identification in this study relied primarily homologues. Classic hallucinogens are typically on the similarity of melting points, with the melting similar in structure to one of several neurotransmitter point of the unknown compound compared to melting substances, serotonin (5-hydroxytryptamine; 5-HT; points of known compounds; results were supported Figure 1) being the most common. Of the 70 or so with UV absorption data when possible. Serotonin was tryptamine analogues, more than 50 have been again identified as a Mucuna constituent by Duke evaluated for hallucinogenic properties, including (1981). Tryptamines were not found, however, in a serotonin, the mushroom-derived agents psilocybin later study in which Lorenzetti et al. (1998) used a and psilocin (4-hydroxy-N,N-dimethyltryptamine), sensitive liquid chromatographic analysis procedure, a method considered more reliable than melting point comparison. Finally, Szabo and Tebbett (2002) using liquid chromatography with a mass spectral detector hydroxy-N,N-dimethyltryptamine (bufotenine), and determined that tryptamine derivatives were indeed N,N-dimethyltryptamine-N-oxide (Farnsworth, 1968), present in Mucuna tissues. among others. While some members of each subgroup are synthetically produced, most were and are The tryptamines, bufotenine and N,N-dimethyl- available in plant or fungus species. tryptamine, are naturally occurring compounds and are structurally related to serotonin (5- Tropical and Subtropical Agroecosystems, 1 (2003): 295 - 307 N, N- Dimethyltryptamine (DMT) N-Methyltryptamine (NMT) cal struct ical structures of ures of selected i sel nes and m nes and m escaline. escaline.
The term hallucination finds its origins in the Latin studies, published material on pharmacodynamics and alucinatio which means "a wandering in the mind." pharmacokinetics consists of a mixture of science and Hallucinogenic compounds are associated with a anecdote, with the science often conducted on animals change in the content of consciousness, which and the anecodotes often related to human includes altered perceptions and moods, time experience.1 Throughout this paper, all presented distortions, visual hallucinations, thought disorders information originates from formal studies -- human, and frequently euphoria. Although other drugs can unless otherwise indicated. Although most formal also elicit these responses, only hallucinogens can studies involving indolealkylamines have focused produce these symptoms without diminishing awareness or incurring delirium (Bridger et al., 1978; Hollister, 1968 and 1984). The mechanism by which these changes in perception occur is not well For a number of years, the following effectively summarized the pharmacokinetic information available for understood, partly because reliable human studies LSD in human subjects: LSD administered intravenously at have been extremely limited, partly because animal a level of 2 µg kg-1 indicated a half-life of 103 min in the models do not necessarily correlate to human plasma with a concentration of 6-7 ng mL-1 at equilibrium experience/physiology. Compared to mode of action ( 30 min after administration; Aghajanian and Bing, 1975; Wagner et al., 1978). primarily on LSD, DMT and 5-MeODMT have hydroxyindoleacetic acid, the major metabolite of 5- frequently represented the tryptamine subgroup.2 HT) even when synthesis of 5-HT has been inhibited, When no data regarding the indolealkylamines of but exhibits no significant effect on brain dopamine interest are available, data from studies conducted levels or on dopamine turnover after synthesis with the structurally related LSD or mescaline may be inhibition. Unlike LSD, DMT also exhibits no effect inserted as a point of reference. on brain norepinephrine levels. Although tryptamine is itself a neurotransmitter active in the central nervous Tryptamine and serotonin
system (CNS), hallucinogenic tryptamine derivatives are believed to adhere more to a serotonergic The potency and activity of intoxicating agents are mechanism than to a mode of action utilizing commonly compared to LSD, one of the most potent tryptamine receptors. Due to the complexity of the psychoactive compounds known. Taken orally, 10 µg serotonergic system, precise modes of action are not is reported to induce a mild euphoria in male subjects well understood. While phenylalkylamines have been with true hallucinogenic doses ranging from 50 to 500 shown to selectively prefer only certain classes of 5- µg (Grinspoon and Bakalar, 1979). In comparison, the HT receptor sites, indolealkylamines have been shown simplest compound under consideration in this study, to bind nonselectively and with high affinity to various tryptamine, has not been reported to possess populations of 5-HT receptor sites. A significant psychoactive properties, although it can increase blood correlation (r > 0.9) between receptor affinities and pressure and cause mild perceptual distortions when both discrimination-derived ED50 values and human peripherally administered (Martin and Sloan, 1970). hallucinogenic potency has been determined Although few studies have been conducted on (Glennon, 1990; Glennon et al., 1992; Titeler et al., tryptamine, it has been demonstrated in animals that 1988). For detailed descriptions regarding neuronal certain physiological effects common to LSD may be and behavioral studies and their resulting impacts on produced, but that behavioral effects, used as an biological models of activity, please consider Davis et indication of human hallucinogenic activity, are not al., 1984; Appel and Rosencrans, 1984; Aghajanian, (Martin et al., 1978). 1984; Jacobs, 1984; Geyer and Krebs, 1994; and The most studied and best understood indole is the neurotransmitter serotonin (5-hydroxytryptamine, 5- DMT and 5-MeODMT
HT). While 5-HT does not itself induce hallucinogenic responses in humans or behavioral responses in The most well-known of the hallucinogenic animals, it is closely implicated in the hallucinogenic tryptamines, DMT, is endogenous to the seeds of process, as centrally located serotonin receptors in the Anadenanthera peregrina, Anadenanthera colubrina, brain and spinal cord have been repeatedly and Mimosa hostilis, the bark of Virola calophylla, demonstrated to provide the main pathways of action and the leaves of Banisteriopsis rusbyana and for psychoactive components. Briefly, excitatory 5- Psychotria viridis, all species native to the Orinoco HT receptors have been shown to induce the basin, Amazonian regions, and Mexico. Intoxicating intoxicating response with inhibitory 5-HT receptors snuffs, containing DMT and frequently 5-MeODMT often mediating the effects, the hallucinogens (by up to 11%; Siegel, 1984) as the primary active themselves acting as agonists or partial agonists ingredients, have been made from these materials (Glennon, 1990; Burris and Sanders-Bush, 1988). In since at least 1500 B.C. Intranasal inhalation is the comparison, biogenic amines such as 5-HT, typical means of administration, as these compounds norepinephrine, and dopamine are considered to are not orally active on their own. For DMT or 5- commonly act as neuromodulators rather than as MeODMT to be active after ingestion, an amine excitatory or inhibitory components. oxidase inhibitor must be mixed into the preparation. Naturally occurring β-carbolines are sometimes used Most intoxicating indolealkylamines exert a stronger for this purpose. Up to 350 mg of DMT has been effect on the central serotonin system than on the taken orally with no resulting hallucinogenic effect central catecholamine system (Bridger et al., 1978). (Turner and Merlis, 1959). Like LSD, DMT decreases the breakdown and transport removal of 5-HT (measured as an increase in When DMT was evaluated for dose-response in brain 5-HT and a decrease in brain 5-HIAA, 5- human trials (Strassman and Qualls, 1994; Strassman et al., 1994), intravenously administered levels of 0.05 mg kg-1 or less were frequently mistaken for placebo 2 It is important to note that not all members of these by the male subjects. Although 0.1 mg kg-1 could be structurally related groups are necessarily psychoactive; reliably distinguished from placebo, feelings of LSD has the non-hallucenogenic analogue 2-bromo-LSD, as tenseness did not progress to a psychoactive state. DMT has 7-hydroxy-DMT. Tropical and Subtropical Agroecosystems, 1 (2003): 295 - 307 The hallucinogenic threshold requires that 15-35 mg psychological effects are similar to those experienced of DMT be inhaled or injected ( 0.2 - 0.5 mg kg-1); for with DMT. Like DMT, 5-MeODMT is inactive orally intentional intoxication, 50-100 mg is usually taken unless a MAOI is present. Metabolism of 5- (Gillin et al., 1976; Grinspoon and Bakalar, 1979). MeODMT dosed to rats is also rapid and clearance of parent (<0.5%) and metabolites (indole acids) is When compared with LSD (often taken orally), the through the urine (Sitaram and McLeod, 1990). onset of effect is rapid, as inhaled/injected DMT takes a more direct route into the bloodstream and by-passes Bufotenine
the gastrointestinal system. First effects begin in a matter of seconds after exposure, peak between 5 and Although bufotenine is found in many of the same 20 min (the acute phase), then diminish to a normal plants as the previously mentioned tryptamines and is level over an additional 30 or so minutes (the known to be produced in the parotid glands of toads secondary phase; Kaplan et al., 1974). In comparison, (Bufo spp), it is not clear whether or not bufotenine the duration of symptoms for LSD (having an possesses any psychoactive properties (reviewed by oral/intravenous threshold of 30-50 µg) is 4 hr, acute, Lyttle et al., 1996). Structurally, bufotenine is and 6 hr, secondary. Oxidative deamination of DMT incapable of passing the blood-brain barrier, but can to the inactive indole acid occurs quickly; within 70 elicit behavioral effects in animals when the dose is min tissue (brain, liver, kidney, and blood) administered directly into the CNS (Glennon et al., concentrations were not measurable in rats after a 10 1980) or when the hydroxyl group is modified by mg kg-1 i.p. dose (Sitaram and McLeod, 1990). acylation for easier passage into the CNS (Gessner and Clearance of parent (<2%) and metabolites is Dankova, 1975). Reported levels of effect in humans, primarily through the urine. Due to a lack of detailed as well as the nature of such effects, are strongly studies in humans, it is not known how well this anecdotal in nature and will not be repeated here. elimination pathway correlates between species, although it is in agreement with observations made Despite the fact that bufotenine (5-hydroxy-N,N- thus far (Kaplan et al., 1974). dimethyltryptamine), an isomer of psilocin (4- hydroxy-N,N-dimethyltryptamine), is classified as a Physiologically, the symptoms induced by DMT are Schedule I controlled substance in the United States similar to those of LSD, but more intense – pupils (DEA registry # 74333), a review of the scientific dilate, blood pressure elevates, pulse rate increases. literature indicates that bufotenine is a pressor agent Psychologically, the rate at which thoughts take place (affecting cardiovascular function, especially heart is perceived to increase, a sense of timelessness often rate and blood pressure) at high doses administered occurs, along with the perceived feeling that solid intravenously or intramuscularly, but not an objects may melt into vibratory patterns (a mixing of hallucinogenic (Chern et al., 1991; McLeod and the senses). Intensely colored geometric patterns/ Sitaram, 1985; Shulgin, 1981; Fozard and Ali, 1978). objects may form, undulate, and reform. Visions or That alteration of cardiac function can in turn affect hallucinations are often quickly paced, one upon the transport of oxygen to the brain may be the source another. A sense of heightened awareness or of belief in bufotenine's psychedelic aspects. Visual enlightenment may occur. The experience may be distortions were reported, along with significant either pleasant or unpleasant, depending in part on the changes to the sinus rhythm when 10 mg of bufotenine setting and mental perspective of the subject prior to were administered intramuscularly (Turner and Merlis, taking the compound. Even when ranked unpleasant, 1959). As a pressor, serotonin is about twice as active DMT is not known for inducing psychotic reactions, as are LSD and mescaline (Bowers, 1972). With frequent use, tolerance (a decrease in or elimination of In the toad genus Bufo, hallucinogenic activity may effect) can occur in a matter of days. Cross-tolerance actually originate with 5-MeODMT, an O-methylated with LSD (both physiological and psychological) has analog of bufotenine, found in only a few of the also been documented and indicates a common known two hundred Bufo species. Although mechanism of action (Koravic and Domino, 1976). bufotenine is present in the venom secreted by the To date, there have been no reports of lethal overdose parotid gland of all toad species, it is far more likely to for the tryptamine derivatives. contribute to a potentially lethal toxicity than to induce any psychoactive effect (Lyttle, 1993). In the venom, Having about the same potency as psilocybin, 5- bufotenine is a minor constituent. Other components MeODMT is a little less than 1% as potent as LSD, include phenylethylamines such as epinephrine (which but considerably more potent than DMT. When may act to increase penetrability across the blood- administered intranasally, the threshold dose is 4-6 mg brain barrier, but this has not been proven), (Grinspoon and Bakalar, 1979). Physiological and norepinephrine, and dopamine, other tryptamine derivatives such as serotonin, and bufodienolides EXPERIMENTAL CONSIDERATIONS
(steroidal derivatives that affect the heart in a manner similar to digitalis or act as potent vasoconstrictors). This study is a continuation of earlier research by Neither bufotenine nor 5-MeODMT have shown Szabo and Tebbett (2002). Previously, the presence of activity when taken orally (Horgan, 1990; McKim, certain indolic alkaloids was ascertained in the tissues 1986) which leaves reported hallucinogenic highs due and seeds of various Mucuna accessions. As a step to "toad-licking" in a questionable state. toward determining whether or not these components are of potential concern in food, feed, or fodder Structure-activity considerations
produced from Mucuna, the components were quantified in fresh and dried plant material. Structure-activity studies have attempted to explain variations in potency, specific symptoms, duration of Sample materials
effects, and observed differences in mode of action on the neuronal level as a function of minor structural The plant materials used in this study originated from differences between related drugs (Nichols and various sources. Most had previously been assayed Glennon, 1984; Jacob and Shulgin, 1994). With for L-dopa content and screened for selected regard to structure, minor differences can have indolealkylamines (Szabo and Tebbett, 2002). In profound effects. For instance, 5-HT, which is preparation for extraction, all seed samples were centrally active in the brain and spinal cord, does not ground in a Wiley mill with a 1-mm stainless steel usually affect activity in the CNS when administered screen. Initial preparations for other sample types are peripherally, as the compound is unable to enter the defined with the source description: (1) Raw seed CNS from the periphery. This limitation is directly from a local variety of Mucuna pruriens found in related to its chemical structure, especially to polar Malawi was supplied by the Rockefeller Foundation- functional groups (hydroxyl group at ring position Malawi. (2) Leaves, stems, pods, and roots from number 5 in 5-HT, also in bufotenine; Shulgin and Mucuna pruriens var. utilis grown in the Rebublic of Nichols, 1978). Formation of an ether (a modification Benin were collected, dried, and ground prior to that decreases polarity) will often disallow this shipment by CIEPCA (Center for Cover Crops limitation, as is shown by the recognized psychoactive Information and Seed Exchange in Africa, Cotonou, effects of 5-MeO-DMT. In contrast, DMT has no Benin). Two whole seed samples (Nord 98 and IITA overtly polar functional groups and also exhibits 98) of the same variety grown in different locations intoxicating symptoms. were also supplied. (3) Raw seed was also sent from the Agronomy Department, Auburn University, On consumption, the enzyme monoamine oxidase Alabama. These samples had not previously been rapidly metabolizes most tryptamine derivatives into screened for the presence of indolic alkaloids. (4) inactive by-products, often into indole acids, before Fresh leaf and stem samples of four Mucuna the agents reach the CNS, frequently while still in accessions were planted, grown in greenhouses, and stages of absorption. Serotonin, for example, is so harvested at the University of Florida, Gainesville, poorly absorbed and has such a short half life in the Florida, from seed supplied by the Agronomy periphery that L-tryptophan, the serotonin precursor, Department, University of Florida and by ECHO must be administered at levels of 3-6 g daily rather (Educational Concerns for Hunger Organization, Inc., than serotonin itself to compromised individuals. For Ft. Myers, Florida). The samples, designated mottled- these reasons, intoxicating preparations intended for Gainesville, ECHO 92023 991E, ECHO 91080 991E, oral application are generally combined with a and ECHO 60002 PG1 were chopped by hand in naturally occurring inhibitor like the harmala alkaloids preparation for analysis. or with one of the commercially available MAOI (monoamine oxidase inhibitors), medically prescribed Sample extraction
antidepressants known to elevate brain amines. This recognized limitation has led to the purposeful design The extraction method was modified from the of chemical structures to avoid enzymatic inactivation. technique described by Brain (1976). Approximately The synthetically produced α-methyltryptamine and 5- 0.5 g of dried plant or seed material was weighed into methoxy-α-methyltryptamine differ from DMT and 5- a culture tube. (For fresh plant and dried pod samples, MeODMT in that the synthetic structures posses a 1 g of material was used with all solvent volumes single methyl group attached to the carbon preceding adjusted accordingly.) The sample was mixed with 3 the amine group which lacks the dimethyl mL of 0.1 N hydrochloric acid, heated in a boiling functionality; this difference allows for oral activity at water bath for 5 min, and allowed to cool to room about the same levels of potency as the natural analogs temperature. Three milliliters of ethanol were then when inhaled or injected (Shulgin and Nichols, 1978). added; the sample was shaken for 10 min by hand and Tropical and Subtropical Agroecosystems, 1 (2003): 295 - 307 centrifuged at 2000 rpm for 10 min. The supernatant (single-ion monitoring) to maximize sensitivity for was removed by pipette to a fresh vial, and the residue quantification. The [M + H]+ ions at m/z 161 for was re-extracted with the supernatants being collected tryptamine, the [M + H] + ions at m/z 177 for 5-HT, together. Ethanol was added to the combined extracts the [M + H] + ions at m/z 205 for bufotenine, the [M + to a final volume of 5 mL. A 1-mL aliquot was then H] + ions at m/z 189 for DMT, and [M + H] + ions at removed and filtered through a syringe packed with m/z 219 for 5-MeODMT were selected for glass wool coupled to a 0.45-µm PTFE syringe filter. Just prior to analysis, caffeine was added as an internal standard (20 µg mL-1). All solvents used were of reagent grade. All water was distilled and deionized. Table 1. Description of instrumentation and Suitability of the extraction method for the indolic alkaloids ( 95% recovery) had previously been determined through a recovery study in which a mixed standard containing all analytes was added to ground seed samples at a level of 0.05% dry wt. Instrumentation: Hewlett-Packard HP1100 system with autosampler, degasser, binary Sample analysis
pump modules, and variable wavelength UV detector (Hewlett- Alkaloid content was determined by liquid Packard Company, Wilmington, DE) chromatography with mass spectrometric detection Column: Adsorbosil using electrospray ionization. (Table 1 contains a 150 mm length; Serial #97032088; detailed description of the instrumentation and parameters.) Stock solutions of tryptamine hydrochloride (99%; Aldrich Chemical, Milwaukee, Phase: Solvent A: 20 mM ammonium WI), serotonin (96.7%; Sigma), N,N-dimethyl- acetate in water tryptamine (Alltech), 5-methoxy-dimethyltryptamine Solvent B: methanol (Sigma), and bufotenine (Radian Analytical Products, Austin, TX) were prepared individually. Bufotenine Gradient: 13% Solvent B for 2 min; and DMT were dissolved in methanol; tryptamine in 13% increased to 100% Solvent B ethanol; and 5-HT and 5-MeODMT in water acidified over 14 min; hold 8 min; 100% to a pH of 3.2 in acetic acid with a few drops of decreased to 13% Solvent B over 2 methanol to assist dilution. A five-point curve (R2 ≥ min; equilibrate 5 min 0.998) of mixed standards was freshly prepared in Column Temp: 25 °C ethanol from the individual stocks each day; each contained 20 µg mL-1 of caffeine to match the sample Injection Vol.: 50 µL UV Detection: 280 nm Qualitatively, the positive confirmation of a Mass Spectrometer compound's identity requires comparison of the Instrumentation: Finnigan LCQ Ion Trap Mass retention time and the pattern of fragmentation ions of Spectrometer (Finnigan MAT, San the sample and the standard. These must all agree within some limit of acceptability, generally, 0.2-0.3 100-500 m/z full scan mode min for the retention time and 5-10% for the ion Electrospray Ionization proportions. Due to the similarity in structures among this particular group of compounds, close retention Capillary Volt: 20 V times and the sharing of fragmentation ions were not Capillary Temp: 220 °C uncommon. There was also the reasonable concern that one of the many previously unrecognized analogues could appear in the extracts. To ensure identification of any target compound believed to be RESULTS AND DISCUSSION
present, that sample extract was spiked to a level of 20 µg mL-1 with a standard of the suspect analyte and re- In the previous screening study (Szabo and Tebbett, analyzed. The unspiked and spiked spectra were then 2002), 5-MeODMT had been identified in each of compared against each other, as well as against the several samples examined, but 5-HT and tryptamine corresponding standard. While identification depended found only in a few select samples. The concentrations on multiple ions, mass spectra of the standards and of these components were estimated to be 0.001%, samples were also collected in selected-ion mode low compared to that of L-dopa ( 5% by weight in the seeds and 0.1-0.5% in plant tissues), but of concern weights of the various samples are presented in Table nonetheless. The earlier screening results along with the current measured alkaloid concentrations for dry Table 2. Summary of assay results. Sample description Estimated concentration (µg g-1 dry wt.) Unknown Bufotenine Malawi, local variety: 5-MeODMT, Tryptamine Benin samples, M. pruriens: 5-MeODMT, Tryptamine Whole seed (Nord 98 ) Whole seed (IITA 98) Gainesville fresh plants: Auburn seed: 90 Day runner white, 024-W 90 Day runner speckled, 024-S Bella Mina speckled, 025 S-1 Bella Mina speckled, 025 S-2 Bella Mina speckled , 025 S-4 Bella Mina light black, 025-LB Edgar farm white, 023-W USA black, 022-B USA white, 022-W Abbreviations: NA, not available; 5-MeODMT, 5-methoxy dimethyltryptamine; 5-HT, serotonin In the current study, neither tryptamine nor DMT were possibly N-methyltryptamine, was determined to be detected in any sample (< 0.5 µg g-1). Although ions present in all plant tissue samples and one seed corresponding to tryptamine were noted at a number sample. Although serotonin was not identified in any of retention times as fragmentation products for other sample tested (<0.5 µg g-1), the levels of the unknown compounds, especially serotonin and bufotenine, indole were estimated against the serotonin standards. tryptamine, itself, was excluded as a possible In root and pod, 5.96 and 4.03 µg g-1 were calculated, constituent at levels ≥0.5 µg g-1 in Mucuna samples respectively, with an average of 8.49 and 3.94 µg g-1, due to discrepancies between observed retention times respectively, in leaf (n=5) and stem (n=5). Only one for the samples and the tryptamine standard. An seed sample (1.70 µg g-1) contained the unknown in unknown compound close to the weight of serotonin, detectable amounts. Bufotenine was also identified in Tropical and Subtropical Agroecosystems, 1 (2003): 295 - 307 most samples, in root at a level of 4.14 µg g-1, but not kg-1) would induce symptoms. The highest measured in the pod sample. In leaf (n=5), stem (n=4) and raw presence of any tryptamine derivative in a seed sample seed (n=15) concentrations averaged 3.46, 3.09, and was 2.25 µg g-1 d.wt. for bufotenine. This correlates 1.48 µg g-1, respectively. As expected, 5-MeODMT to 0. 00225 mg g-1 in dried seed. Assuming 150 g of was detected in all samples. In root and pod, dried seed would be consumed by the 70 kg subject, concentrations of 1.76 and 1.29 µg g-1, respectively, he would consume 0.0048 mg kg-1, a level more than were found with average levels of 1.44, 1.48, and 0.45 10 times below the inhaled threshold, and much µg g-1 present in leaf (n=5), stem (n=5), and seed further below any ingested threshold. This amount of (n=15), respectively. Compared to L-dopa, the tryptamine derivative would not be psychoactive on detected indoles were present at roughly 0.0001% by ingestion. To address the additive effect, one can take weight, lower than had been previously hypothesized. the seed sample with the highest total indole content, 3.53 µg g-1 in seed, and repeat the above assumptions. Differences in constituent identifications between the In this case, the consumed concentration would be earlier study (Szabo and Tebbett, 2002) and this one 0.008 mg/kg body weight, about twice the level are possibly due to loss or to metabolism during calculated for the individual alkaloids, but still below a storage, although differences are most likely due to the level of concern. low concentrations, structural similarities, and to an earlier mobile phase that had not been as finely Although indolic alkaloids are generally stable to optimized for separations of these closely related freezing, drying and the elevated temperatures of structures. The ions associated with tryptamine were cooking, they are water-soluble, and so can be also among the major fragments formed for the other removed by boiling. For example, the psychoactive indoles, most strongly for 5-HT and bufotenine. In mushrooms of the Psilocybe genus are often frozen or addition, the ions of 5-HT and bufotenine strongly dried for storage. Occasionally they are boiled prior to overlapped in profile. Due to the structural similarities use, in which case the water is ingested rather than the among the derivatives, this was not surprising. With mushroom as the potency of the mushrooms is the improved separation program and with a larger decreased during processing (Spoerke and Hall, 1990). presence of analyte in each sample, differentiating the Psilocin, psilocybin, and other tryptamine derivatives analogues was simplified – sufficiently so that an are contained in the tissues at total levels around 15 unknown tryptamine could be recognized, quantities mg per 30 g of mushroom, much higher than the estimated, and an identification suggested. Based on concentrations of tryptamine derivatives in Mucuna. the probable molecular weight, as estimated from the likely molecular ion (the largest ion present at a high Regarding the obvious concern of chromosomal level after the molecules had been fragmented in the damage and the possibility of elevated levels of birth detector) in the fragmentation pattern, and retention defects over time due to exposure of time in relation to the other indole derivatives, the indolealkylamines, there is no information related to unknown may be N-methyltryptamine. In at least the tryptamines directly. However, a multi- some plant species where DMT and/or 5-MeODMT generational study of routine mescaline (peyote) users are endogenous, N-methyltryptamine has also been has indicated no adverse effect (Dorrance et al., 1975). identified (Holmstedt and Lindgren, 1979). When considering the implications of this information, one should note that both men and women partake and Now that it has been determined Mucuna beans and that exposure levels are true hallucinogenic levels, and plant tissues do indeed contain psychoactive indolic not ones below threshold. Unfortunately, there has alkaloids in measurable amounts, what does this mean been no such study conducted among the snuff-users for humans and animals consuming food and feed of South America. products? Two factors should immediately be considered: (1) threshold limits of effect for oral Does food preparation affect indolic alkaloid levels? administration, and (2) effects of preparation and Are these levels sufficiently high to be of concern to cooking processes. Because of structural similarities, healthy adults and children, and to health- these agents share the same mechanism of action, compromised persons? Although reliable information which means that additive levels must be evaluated in on these topics is limited, the detected levels of addition to levels of the individual components. To indolealkylamines are well below any known simplify this approach, one can consider only the threshold level for oral activity even before one takes tryptamine derivative (5-MeODMT) with the lowest food preparation into account. Based on chemical threshold (4-6 mg) when administered intranasally. properties, boiling or cracking and boiling the seed Like most naturally occurring tryptamines, it is should certainly decrease the alkaloid content even inactive orally. However, for the sake of argument, further, along with the L-dopa content. Regarding one can assume 4 mg in a 70 kg human male (0.05 mg healthy adults, pregnant women, and children, again, the best evidence for use is likely found in the sub- chemical, Behavioral, and Clinical Perspectives, p 77- threshold levels of the components and in the multi- 94. Ed by Jacobs, BL. Raven Press, New York. generational study of traditional peyote users, which showed no effect. For anyone taking monoamine Bowers, MJ, Jr. 1972. Acute psychosis induced by oxidase inhibitors Mucuna consumption should psychotomimetic drug abuse, I. Clinical findings. probably be limited until a physician can be consulted AMA Archives of General Psychiatry 27: 437-440. or until additional research clarifies any potential for adverse effect. To secure the future of Mucuna as a Brain, KR. 1976. Accumulation of L-Dopa in food for human consumption, the evaluation of Cultures from Mucuna pruriens. Plant Science Letters prepared food products for indolealkylamine content should allay any remaining concerns. Bressani, R. 1993. Grain quality of common beans. Food Reviews International. 9: 217-297. The author expresses her sincere appreciation to the Bridger, WH, Barr, GA, Gibbons, JL, Gorelick, DA. following people and institutions: Robert Gilbert 1978. Dual Effects of LSD, Mescaline, and DMT. In (Rockefeller Foundation-Malawi) for the seed from The Psychopharmacology of Hallucinogens, p 150- Malawi; Albert Etèka, Bob Carsky and Kokou 180. Pergamon Press, Inc., Elmsford, New York. Ahouanton from CIEPCA (Cotonou, Benin) for the Mucuna pruriens var. utilis accessions from Benin; Burris, KD, Sanders-Bush, E. 1988. Hallucinogens Marjatta Eilittä (consultant), Lynn Sollenberger, directly activate serotonin 5-HT1c receptors in choroid Richard Fethiere, and Ken Buhr (Department of plexus. Society of Neuroscience Abstracts. 14: 553. Agronomy, University of Florida), and Daniel Sonke (ECHO, Ft. Meyers, Florida) for planting, growing, Capo-chichi, LJA, Eilittä, M, Carsky, RJ, Gilbert, RA, and harvesting samples, volunteering greenhouse Maasdorp, M. This volume. Influence of latitude on space, and for donating the seed for the fresh mottled- L-dopa synthesis in Mucuna seeds. Gainesville material and ECHO accessions grown in Gainesville, Florida; Ludovic Capo-Chichi (University Chern, MS, Ray, CY, Wu, DL. 1991. Biologic of Alabama, Birmingham, Alabama) for seed samples; intoxication due to digitalis-like substance after Carolyn Diaz and Matthew Bean (Analytical ingestion of cooked toad soup. American Journal of Toxicology Core Lab staff members) for the creative Cardiology 67: 443-444. and consistent effort that generated these results. The author also wishes to acknowledge partial funding Davis, M, Kehne, JH, Commissaris, RL, Geyer, MA. from the Rockefeller Foundation through the project, 1984. Effects of hallucinogens on unconditioned Increasing Mucuna's Potential as a Food and Feed behaviors of animals. In Hallucinogens: Crop, coordinated by the Center for Cover Crops Neurochemical, Behavioral, and Clinical Perspectives, Information and Seed Exchange in Africa (CIEPCA) p 35-75. Ed by Jacobs, BL. Raven Press, New York. at the International Institute for Tropical Agriculture Daxenbichler, ME, VanEtten, CH, Hallinan, EA, Earle, FR. 1971. Seeds as sources of L-dopa. Journal REFERENCES
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Psychopharma- cology 94: 213-216. Submitted February 20, 2003 - Accepted February 26, 2003

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