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Journal of Ethnopharmacology 50
(1996) 119-130
Psychoactive constituents of the genus Sceletium
Rceived 13 July 1995;
accepted 27 November 1995
ABSTRACT
The use by the Khoisan of South Africa of Sceletium plants in
psychoactive preparations has often been alluded to in the
literature. However, much of it is fragmentary and contradictory.
The current review reassembles the historical data recorded over a
300-year period, describes techniques for the preparation and use of
'kougoed' from plants of Sceletium and documents the subjective
experiences of a number of contemporary users. Apart from chewing
the dried product, after 'fermentation', there are reports of uses
as tinctures for sedation and analgesia, chewing the material
directly and smoking the residue after chewing.
The symbolic connections of Sceletium with eland antelopes, the
'trance animal's' par excellence of the San hunter-gatherers is
noted. Observations by Paterson (1789) and reports of contemporary
users indicate a synergism and potentiation with smoked Cannabis.
There is no evidence to support the view that 'kougoed' or Sceletium
alkaloids are hallucinogenic. The alkaloid distribution in Sceletium
and other members of the family Mesembryanthemaceae are considered.
Chemical studies have indicated as many as nine alkaloids in
Sceletium which fall into three distinct structural categories.
Mesembrine, the alkaloid first isolated and named is not the
dominant constituent of plants and is weakly narcotic. Evidence is
assembled to suggest that traditional and contemporary methods of
preparation serve to reduce levels of potentially harmful oxalates,
which are found in Sceletium and other Mesembryanthemaceae. It is
concluded that there is a need for further pharmacological studies
on these alkaloids, based on their narcotic-anxiolytic properties,
strong synergism with other psychornime tics, moderate toxicity and
anti-cancer activity.
1. Introduction
It has been observed (Schultes and Hofmann, 1979; Schultes and
Farnsworth, 1980) that of the 200 or more psychoactive plants that
have been identified world-wide, nearly 90% are native to the
Americas. There is little doubt that much of this apparent
discrepancy is the result of insufficient study. For instance,
Guzman's (1983) monograph indicates an absence of psychoactive
species of Psilocybe (Fr.) Quél in sub-Saharan Africa. The recent
discovery in KwaZulu-Natal of a new species of hallucinogenic
fungus, Psilopybe natalensis Gartz and Smith (Gartz et al., 1995),
clearly attests to the under-investigation of the southern African
flora for psychoactive plants. South Africa is both floristically
rich and diverse, and local attention has recently been focused on
the use of information from folk medicine as a starting point for
pharmaceutical research (Fourie et al., 1992). With few exceptions,
the peoples of Africa have exploited psychotropic plants to only a
limited degree (Schultes, 1977; Emboden, 1979; Dobkin de Rios, 1990;
Weil and Davis, 1994), possibly because of cultural restraints.
Although not mentioned in the classical ethnography of the Khoisan,
use of plants of the genus Sceletium N.E.Br. has entered the
literature (Watt and Breyer-Brandwijk, 1962; Schultes, 1970). Plants
were reportedly highly esteemed and sought after by both Khoi
pastoralists and San (Bushmen) hunter-gatherers (Watt and
Breyer-Brandwijk, 1962; Rood, 1994), yet there is a distinct lack of
specific information on details such as preparation, psychoactivity
and species used. Furthermore, only limited human pharmacological
studies on the active constituent(s) of this plant appear to have
been done.
The purpose of this review is threefold. Firstly, we wish to
reassemble the data accumulated over some 300 years, thereby
highlighting the neglect and uncertainties associated with the genus
Sceletium in particular, (originally included in Mesembryanthemum
L.) and the Mesembryanthemaceae Fenzl in general. The second is to
record what was probably the original folk method of preparation of
Sceletium, based on field observations. Thirdly, the psychoactive
properties of Sceletium are documented by reporting on the
experiences of several test subjects.
2. Historical record
Historically, at least as far back as the 17th century, the Little
Karoo and Namaqualand, two localities where Sceletium species are
known to occur, were inhabited by nomadic groups of Khoi and San
(see, for example, van der Stel's Journal of the Expedition into
Namaqualand; Waterhouse, 1932). Elphick (1977) points out that the
Khoi were originally hunter-gatherers who adopted pastoralism and,
as a result, effected major changes in the economy, size and social
structure of the hunter-gatherer band. This thesis adequately
accounts for both the cultural similarities and differences between
Khoi and San. The utilisation of Sceletium species appears to be one
such case of cultural convergence between Khoi and San, as is its
symbolic connections with the eland (Taurotragus oryx Pallas),
indicating a shared history of hunting and gathering. Lewis Williams
(1981) has drawn attention to the symbolic significance of the eland
in San thought as the 'trance animal' par excellence. It is a
predominant and widely recurring feature of San rock art in southern
Africa. Quite apart from its economic importance as one of the major
objects of the hunt, the eland was symbolically linked to fertility,
marriage, rainmaking, divination, dancing, trance and healing.
Whether or not Sceletium was chewed or mixed with 'dagga' (Cannabis
sativa L.) and smoked, there are suggestions that it induced Khoi
users to dance (Laidler, 1928). The Khoi of the Little Karoo
certainly referred to Sceletium and the eland by the same term
'Kanna' (sometimes also spelt 'channa' or 'canna' (c.f. Burchell,
1822). Hence, the derivation of the place-name 'Kannaland' (or 'Canna
Land', Raper and Boucher, 1988) which was used by the early white
settlers in reference to the Little Karoo, was doubtless a
reflection of the fact that Sceletium and eland cooccurred in
abundance (Nienaber and Raper, 1977). The term 'Kanna' is not to be
confused with 'ganna' (Salsola dealata Botsch.), which the early
settlers used in soap making, nor with 'kamma', the Khoi term for
water; there appears to have been a considerable degree of confusion
in some of the early writings with respect to the vernacular name
given to Sceletium by the indigenous peoples. It is recorded that in
1662 van Riebeeck bartered with the local inhabitants, in return
receiving sheep and 'kanna'. This plant was prized by the Europeans
as a ginseng-like herb (Laidler, 1928), and is unlikely to have been
hallucinogenic, although Kolben (1738) noted that the scarce root
was 'the greatest Chearer of the Spirits, and the noblest
Restorative in the World'. He indicates some uncertainty about the
plant, but cites a Father Tachart's commentary: 'tis something like
the 'European Mandragora', but much less ... it resembles the 'Mandragora'
pretty nearly in its effects too'.
From the labelled illustration presented (Aureliana canadensis), it
is clear that the rootstock is mandrake-like, but the plant clearly
not of the Mesembryanthemaceae. In all probability Kolben's
illustration was used for general effect rather than botanical
accuracy.
Much of the early confusion in naming of plants appears to result
from settlers confusing similarsounding words of the indigenous
languages, aggravated by looseness and inaccuracies. It is easy to
corrupt the Dutch colonists 'channa' to 'kanna' or 'canna'. Smith
(1966) provides a clear indication of this confusion in his
dictionary of common plant names of South Africa. Errors have been
perpetuated in some of the more recent literature, where 'kanna' has
been used to describe 'kougoed' or 'kauwgoed' prepared from
Sceletium (e.g. the Merck Index; Jacobsen, 1960). Nevertheless, it
is recorded in 1685 by van der Stel, the second colonial governor of
the Dutch Cape colony, in his journal:
'They chew mostly a certain plant which they call Canna and which
they bruise, roots as well as the stem, between the stones and store
and preserve in sewn-up sheepskins. When we came to the Coperbergh
in October, it was being gathered from the surrounding hills by
everybody (to serve as a supply for the whole year). They use it as
the Indians use betel or areca, and are of a very cheerful nature'.
Fig. 1. Illustration from Simon van der Stel's Journal of 1685 of
putative mesembryanthemaceous flower and skeletoid leaf typical of
Sceletium.
Accompanying the illustration (Fig. 1), which leaves little doubt
that the plant was a species of Sceletium was the caption:
'This plant is found with the Namaquaas and then only on some of
their mountains... It is held by them and surrounding tribes in as
great esteem as the betel or areca with the Indians. They chew its
stem as well as the roots, mostly all day, and become intoxicated by
it, so that on account of this effect and its fragrance and hearty
taste one can expect some profit from its cultivation' (Waterhouse,
1932; Waterhouse et al., 1979).
This observation is probably the first to attribute intoxicating
properties to Sceletium. The value of Sceletium as a trade item and
its value in suppressing hunger and thirst, were noted by Thunberg
in his 1773 expedition:
'The Hottentots come far and near to fetch this shrub with the root,
leaves and all, which they beat together, and afterwards twist them
up like pig-tail tobacco; after which they let the mass ferment and
keep it by them for chewing, especially when they are thirsty. If
chewed immediately after fermentation, it intoxicates. The word kon,
is said to signify the quid; the colonists call it Canna-root... The
Hottentots, who live near this spot.. hawke it about, frequently to
a great distance, and exchange it for cattle and other commodities.'
(Thunberg, 1794).
From these accounts it is apparent that there was a seasonal and
almost ritualistic gathering at a specific locality, and that the
value of the material warranted such collection, storage, and
barter. The reputed intoxicating effects, as well as preparation by
fermentation, are noteworthy and will be discussed further (Section
5).
Plants of the genus Sceletium were first shown to contain an
alkaloid by Meiring (1898) who isolated the, then, unknown
mesembrine from Sceletium tortuosum (L.) N.E.Br. and demonstrated a
rapid physiological response in frogs to subcutaneous injection of a
'few drops' of the alkaloid. His bioassays also included guinea
pigs, which were noted as being much more tolerant of the alkaloid.
Uneasiness and loss of appetite were the only recorded responses.
Meiring also noted that some frogs and guinea pigs died. Some time
later, several Mesembryanthemum samples were sent by H.W.R. Marloth,
a pharmacist, analytical chemist and botanist (Gunn and Codd, 1981)
to Professor C. Hartwich in Zurich. E. Zwicky, a student of the
latter, produced a dissertation Über channa' in 1914 in which
Sceletium expansum (L.) L. Bolus and Sceletium tortuosum (L.) N.E.Br.
were reported to contain alkaloids, to which the trivial name
mesembrin (now mesembrine) was given.
The impression is given (Herre, 1971) that Sceletium is a richer
source of alkaloids than other Mesembryanthemums, although
Mesembryanthemum crystallinum L. is also reputedly relatively rich
in alkaloids. However, the latter also contains high levels of
oxalates, which is a gastric irritant that may cause bladder or
kidney stones.
The fact that farmers reputedly use this plant to take hair off
animal skins (Laidler, 1928) suggests its ingestion would be
contra-indicated!
3. Alkaloid distribution within the Mesernbryanthernaceae
It is impossible, based on available information to draw any
conclusions about the taxonomic implications of alkaloid
distribution in the Mesembryanthemaceae. Currently two subfamilies
are recognized, the Mesembryanthemoideae and Ruschioideae, and some
of the recent taxonomy is in a state of flux (Bittrich, 1986;
Hartmann, 1991). It has been suggested, for instance, that Sceletium
N.E.Br. is a basionym for Phyllobolus subgenus Sceletium (N.E.Br.)
Bittrich, but species names have not been suggested (Bittrich,
1986).
Nevertheless, using the data provided by Watt and Breyer-Brandwijk
(1962) and the older classification scheme presented by Herre (1971)
it is possible to note some interesting patterns of alkaloid
distribution by plant genera. The genus Sceletium N.E.Br. is in one
of the five subtribes in the subfamily Mesembryanthemoideae and five
of the six genera investigated tested positive for alkaloid (Aptenia
N.E.Br., Prenia N.E.Br., Sceletium N.E.Br., Aridaria N.E.Br.,
Psilocaulon N.E.Br.). Within the larger subfamily Ruschioideae, only
five of the twenty-two subtribes of the tribe Ruschieae have been
investigated, and that somewhat unrepresentatively. Four out of five
species of Ruschia Schwantes (subtribe Ruschfinae) were tested
positive; Lampranthus N.E.Br. (subtribe Lampranthinae) tested both
positive and negative. Six out of the nine species investigated in
the subtribe Delospermatinae were positive (Delosperma N.E.Br.,
Drosanthemum Schwantes, Trichodiadema Schwantes, Mestoklema N.E.Br.
ex Glen). In the subtribes Conophytinae and Malephorinae, the genera
Conophytum N.E.Br. and Glottiphyllum Haw. tested alkaloid-positive.
It should be stressed that these were general alkaloid tests and do
not necessarily indicate only mesembrine-like alkaloids. For
example, Rimington and Roets (1937) isolated piperidine
hydrochloride as the toxic alkaloidal constituent of Psilocaulon
absimile N.E.Br.
Additionally, although the tests were not quantitative, some plants
possessed only traces of alkaloid, namely Delosperma subincanum
(Haw.) Schwantes., Delosperma ecklonis Salm-Dyck Schwantes,
Lampranthus deltoides (L.) Wijnands and Ruschia rubricalis (Haw.) L.
Bolus.
It should be noted that 116 genera are recognised within the
Mesembryanthemaceae (Hartmann, 1991), some of which contain less
than ten species (Apienia N.E.Br., Prenia N.E.Br. and Mestoklema
N.E.Br. ex Glen). Whereas there are over one hundred species in each
of the genera Drosanthemum Schwantes and Delosperma N. E. Br., over
two hundred and three hundred species are known for Lampranthus
N.E.Br. and Ruschia Schwantes, respectively (Amold and de Wet,
1993). The extent of under-investigation of the Mesembryanthemaceae
with respect to alkaloids is illustrated in Fig. 2 where twelve of
the thirteen genera (Psilocaulon is excluded, see above) which
tested alkaloidpositive by Zwicky are presented graphically, by the
number of species. It is a salutatory observation that of the
possible number of species, less than 0.04% have been investigated.
Several points warrant further comment and investigation. Levels of
secondary plant products, including alkaloids, are strongly
influenced by factors such as the age of plants, growing conditions,
season and even geographical race. Turnover and degradation of plant
alkaloids is a well-established concept and seasonal fluctuations in
levels have been documented in many cases (Barz and Koster, 1981).
Although many Mesembryanthemums were introduced into cultivation in
Europe by early plant collectors in the Cape there is a paucity of'
phytochemical studies. Sceletium was apparently grown in England
from 1705 (Bolus, 1928). Haworth (1794) recorded that the 'houseleek
leav'd fig marygold' (Sceletium expansum) flowered abundantly
between June and August, while Sceletium tortuosum, the 'tortuose
figmarygold' acquired a considerable stem with age. Sceletium
anatomicum (Haw.) L. Bolus, the 1 skeleton-leav'd fig-marygold' was
cultivated somewhat later (Aiton, 1811). Herre (1971) reported that
plants cultivated in Germany did not form alkaloids, whereas those
cultivated in the United States did (further details not given; see
below). The precise basis for this discrepancy awaits elucidation.
Some twenty-four species of Sceletium are recognised, but only
Sceletium joubertii L. Bolus, Sceletium namaquense L. Bolus,
Sceletium strictum L. Bolus, Sceletium tortuosum (L.) N.E.Br. have
been investigated chemically and shown to contain mesembrine-like
alkaloids. Studies by Jeffs et al. (1971) indicated greater
biosynthesis of alkaloids in Sceletium strictum L. Bolus during the
spring and summer, suggesting that levels may change seasonally. It
is significant that within genera of the Mesembryanthemaceae,
different species were tested both alkaloid-positive and negative.
Alkaloids based on phenylalaninetyrosine are found in the Cactaceae
and the 'mesembrine variant' is formed in the Mesembryanthemaceae (Hegnauer,
1988). Both these families are placed in the superorder
Caryophyllidae (Rowley, 1978). Although reference has been made to
the alkaloids in Sceletium being either cocaine-like (Jacobson,
1960) or hyoscyarnine-like (Watt and Breyer-Brandwijk, 1962; Lewis
and Elvin-Lewis, 1977), more correctly, they show structural
similarity to the Amaryllidaceae alkaloids of the crinane class (Jeffs
et al., 1971; Schultes, 1977).
Although there has been support for taxonomically discrete alkaloids
and alkaloid pathways at family and order levels its significance
may now be questionable. Both amaryllidaceous and mesembrine-type
alkaloids share a common biogenetic pathway, although the
biosynthetic pathways are fundamentally different (Jeffs et al.,
1978). However, the presence of mesembrine alkaloids in Narcissus
pallidulus (Bastida et al., 1989) may suggest that such discrete
chemotaxononic criteria not be as sharp as previously believed (Hegnauer,
1988).
Sceletium tortuosum (L.) N.E.Br. was reported to contain 0.3% and
0.86% mesembrine in the leaves and stems, respectively (Watt and
Breyer Brandwijk, 1932). Popelak and Lettenbauer (1968) reported
that levels of alkaloids in 'kougoed' ranged from 1-1.5%, while
mesembrine and mesembrenine levels were 0.7 and 0.2%, respectively.
While this suggests that mesembrine may often be the most abundant
alkaloid, it is important to note that the phenolic alkaloid
constituents of the plant represent a highly complex,
multi-component mixture (Jeffs et al., 1974) with as many as nine
alkaloidal components (Popelak and Lettenbauer, 1968). Some of these
are illustrated in Fig. 3, along with two synthetic analogues which
have been patented by the Tanabe Seiyaku Company of Osaka, Japan.
These had weak sedative effects on reserpine-induced central
inhibition tests (Nabe, personal communication). Jeffs et al. (1974)
presented a unified biogenetic scheme of the Sceletium alkaloids and
distinguished three broad structural categories. One is typified by
mesembrine, sceletenone, mesembrenone and mesembranol. A different
skeletal type is typified by the dehydrojoubertiamine molecule (Fig.
3), first isolated from Sceletium joubertii by Arridt and Kruger
(1970). Interestingly, these workers also reported the presence of
hordenine in this species. Unidentified species of Delosperma have
been reported to contain methyltryptarnine and dimethyItryptarnine
(Smith, 1977), although these would not be psychoactive orally
without a monoamine oxidase inhibitor (Schultes, 1976; McKenna et
al., 1984). Sceletium tortuosum was found to contain a third
structural variant, Sceletium A4 and tortuosamine (Snyckers et al.,
1971). Jeffs et al. (1970) found that 3-year-old plants of Sceletium
strictum grown from seed yielded, from a dry cake weight of 151 g,
some 4 g of alkaloid. Over half of this was demethylmesembrenol and
demethylmesembranol, followed by mesembrenol, mesembrine,
mesembranol, mesembrenone (Fig. 4). Curiously, on one occasion o-acetylmesembrenol
proved to be the major alkaloid. In a later study (Jeffs et al.,
1974) 3.5 kg dry weight Sceletium namaquense yielded 50 g of
alkaloidal material. When 20g were subjected to column
chromatography, formyltortuosamine and unidentified alkaloids
predominated, followed by mesembranol, mesembrenone, mesembrine,
unidentified alkaloids and mesembrenone, and Sceletium A4 alkaloid.
These vastly different alkaloid levels and types serve to highlight
our poor state of knowledge, and suggest that a clear understanding
of the psychoactive properties of 'kougoed', and of alkaloid
biosynthesis by the plants, has yet to be achieved.
4. Alkaloid activity of Sceletium as reported in the literature
There are many reports in the literature concerning the activity and
use of 'kougoed' by the indigenous peoples. How many are based on
critical observation, as opposed to hearsay is difficult to
determine. Laidler (1928) notes that it was: 'chewed and retained in
the mouth for a while, when their spirits would rise, eyes brighten
and faces take on a jovial air, and they would commence to dance.
But if indulged in to excess it robbed them of their senses and they
became intoxicated.'
Reputed negative side effects include headaches, listlessness, loss
of appetite and depression (Marloth, 1913). The narcotic properties
of the product are frequently cited in the literature, supposedly
only after the 'fermentation' process (Watt and Breyer-Brandwijk
1962; see below). However, tinctures were used by the early white
settlers as a sedative, and chewing of the leaves was useful for
toothache and stomach pains (Laidler, 1928). Zwicky (1914) reported
discomfort, analgesia and a slight headache following ingestion of'
kougoed', swallowing a decoction, or taking the hydrochloride salt
of the alkaloid. No stimulatory action was observed. Perhaps the
most remarkable claim is to be found in Watt and Breyer-Brandwijk
(1962) who cite the observations of a mining engineer (and
apparently also a social scientist and moralist!). The Nama peoples
had a 'universal addiction' to the use of 'kougoed' which 'produces
visions' and led to a 'serious degree of moral degeneration
particularly with regard to veracity and sex'. This unsubstantiated
notion was later promulgated by Lewis and Elvin-Lewis (1977).
Although 'kougoed' was primarily chewed, there are reports of it
being taken as a tea (Jacobsen 1960; Watt and Breyer-Brandwijk,
1962) and also as a snuff (Jacobsen, 1960). This latter mode of
administration has also been used for the 'keng-keng' of the Griquas
who used another genus of the Mesembryanthemaceae, Rabaiea albinota
(Haw.) N.E.Br. (= Nananthus albinotus N.E.Br.) as an additive to
tobacco or snuff (Emboden, 1979). Since the narcotic effect of 'kougoed'
can be effectively achieved sublingually, there is little reason to
doubt the efficacy of administration by snuff. Smoke-derived
volatiles would have a somewhat different chemistry, but could
presumably have been just as effective pharmacologically. Of
relevance in this regard Thunberg (1794) wrote in his journal of the
San: 'These people chew 'Canna' (Mesembryanthemum) and afterwards
smoke it'. Paterson, a traveller of the same period, recorded in
1789:
'We now proceeded ... to enter into a country which is, perhaps, one
of the most barren in the world. This is called the Channa Land: and
derives its name from a species of Mezembryanthimum (sic), which is
called Channa by the natives, and is exceedingly esteemed among
them. They make use of it both in chewing and in smoaking (sic);
when mixed with the Dacka (sic) is very intoxicating, and which
appeared to be of that species of hemp which is used in the East
Indies by the name of Bang'.
5. Field studies and pharmacological investigations
In view of the somewhat contradictory information about Sceletium
and 'kougoed', one of the authors undertook a field trip to
Namaqualand where plants are collected and prepared using
traditional methods, for commercial resale. In keeping with
literature observations, the plant material is crushed between
stones following harvest and allowed to remain in closed containers
for several days to 'ferment'. An informant reported that
historically, a skin or canvas bag was used as a fermentation
vessel, but that these have been replaced by plastic bags. The
informant detailed his technique:
'Leave the bag of crushed 'kougoed' in the sun to get warm; its not
necessary to put it (the bag) in the shade, it gets shade at night,
and the sun doesn't harm it. The plant is left to sweat. After 2-3
days the bag is opened, the 'kougoed' is mixed around, and then the
bag is tightly closed again. On the 8th day after the crushing, the
bag is opened and the 'kougoed' is spread out to dry in the sun, as
when you dry raisins. You leave it out until it is dry. If you don't
do the whole thing, the plant won't have power. If you eat the fresh
plant nothing will happen - it doesn't have power. I learned to
prepare it from my father'.
The finished product is stringy, light brown and unattractive in
appearance. The informant noted that the season of collection of
plants was important; plants collected too early would posses less
psychoactivity.
A second informant described an alternative preparation technique,
employed when the user seeks to rapidly prepare 'kougoed'. A small
fire is made over sand, and when it dies down, the ashes are scraped
aside, and a hollow made in the sand. A freshly picked, whole
Sceletium plant is placed in this excavation, and covered with hot
sand. An hour later the baked plant product is recovered, reputedly
with acquired properties similar to the conventionally prepared
material. Lewis-Williams (1981) describes a similar method for
preparing eland fat among the San, the only difference being that it
was left to cook overnight. In the Coloured community, to this day,
'ou vet' (old fat) is a colloquial expression for dagga (Cannabis
sativa).
On one occasion two of the authors took 2g of
conventionally-prepared 'kougoed' by mouth with a small quantity of
alcohol, and held the material in the mouth for 10 min. Some of the
product was swallowed with saliva during this period. No major
discomfort was encountered and after about 30 min both subjects felt
a 'tranquil mellowness'. There was no impairment of motor function,
and no visual hallucinations were experienced. On a separate
occasion, 2 weeks later, the subjects took 1g of material prepared
by another of the coauthors. This material induced the same effects
as previously, but appeared to be slightly stronger. This second
sample, however, differed from the first in several respects: the
preparation included the root, and was prepared in a different
season from plants of different origin. When the subjects further
attempted to ingest unfermented plant material which had been
freeze-dried, by mouth, the acidity was most objectionable and the
exercise was discontinued. The discomfort was not unlike that of
placing a crystal of oxalic acid under tile tongue; the pH of
aqueous extracts of freeze-dried material was later determined to be
between 5 and 5.5.
An analysis of this material using the technique of Sutikno et al.
(1987) indicated levels of 3.6-5.1% oxalate. This is higher than the
levels of 1.9% reported for elephant grass by those authors, but
falls within the median range for oxalates in crop plants reported
by Libert and Franceschi (1987). Our observation, and reports by
others of oxalates in Sceletium (Watt and Breyer-Brandwijk, 1962;
Kellermah et al., 1988) have led us to the view that perhaps the
physical crushing of the plant and the fermentation process may, in
some way, ameliorate the potentially harmful effects of oxalic acid.
Free oxalic acid is likely to complex with cell wall-associated
calcium salts and precipitate as calcium oxalate when plant material
is crushed.
Hanson et al. (1989) have suggested that a low bioavailability of
oxalates in plant tissues may be a function of high ratios of
minerals such as calcium. and magnesium to oxalate.
Oxalates are degraded by microbial populations in the
gastrointestinal tract of humans, ruminants and non-ruminant
herbivores (Daniel et al., 1987). There is evidence that adaptive
changes in microbial microflora may reduce oxalate absorbtion and
toxicity (Argenzio et al., 1988). Allison et al. (1985) have
proposed that these anaerobes be named Oxalobacter formigenes and it
has been suggested that soils and lake sediments may serve as an
inoculum. for oxalate degrading organisms in the digestive tract of
animals (Smith et al., 1985). We would like to suggest that the
crushing process, prior to anaerobic fermentation would introduce
oxalate-degrading microbes into the skin or plastic bag and so
ameliorate the potential toxic effects of oxalic acid. The use of
Mesembryanthemaceae to initiate fermentation for alcohol or
breadmaking is well documented (Juritz, 1906; Watt and
Breyer-Brandwift, 1962), so that the microbiology of 'fermentation'
in 'kougoed' is likely to be quite complex.
The second preparatory method involving burying plant material in
hot sand may also have a scientific basis. Oxalic acid is a simple
dicarboxylic acid, and considerable sublimation is likely to occur
at temperatures above its melting point of 101-102'C; on the other
hand, mesembrine only boils between 186-190'C (Merck Index).
Hence the use of this simple physical technique may achieve the same
result as the more traditional 'fermentation' process by removing
oxalates, and drying the material while retaining alkaloids.
Additional information on the effect of 'kougoed' has been
documented from a dozen individuals who self-experimented with the
traditionally prepared material, and provided oral anecdotes of
these experiences. Most users found that the 'kougoed' induced a
marked anxiolytic effect. One informant used approximately 5 ml of
powdered 'kougoed' orally before giving a lecture that he was
anxious about. He reported feeling relaxed throughout the lecture,
with no cognitive impairment. Many users felt that 'kougoed', in
addition to alcohol or on its own, enhanced social intercourse at
parties and functions. Users felt considerably less inhibited and
self-conscious, and more open than usual in conversation with
strangers. One user claimed that she felt that 'kougoed' was a
'truth drug'.
Of 'kougoed', some felt that there was a synergistic effect with
alcohol, and with smoked 'dagga' (Cannabis sativa). One
experimenter, a poly-substance abuser, used 'kougoed' in addition to
alcohol (whisky) and smoked 'dagga'. He experienced a traumatic
flashback to a violent event he had participated in during a
regional armed conflict. Another experimenter, who on two separate
occasions smoked 'dagga' after chewing 'kougoed', reported seeing
distinct visions of the Sceletium flower and was able to accurately
describe its form and colour, without ever having seen a specimen of
it. The chewing of 'kougoed' was reported to greatly enhance the
psychoactivity of an inferior grade of Cannabis smoked shortly
thereafter (see also 4, above, Paterson's commentary on synergism).
A poly-substance abuser addicted to nicotine and a frequent abuser
of alcohol and 'dagga', reported that after using a single dose of 'kougoed',
he had felt no craving for alcohol, tobacco or 'dagga' for 4 days.
Some reported euphoria as well as a feeling of meditative
tranquillity. Several users felt that the relaxation induced by 'kougoed'
enabled one to focus on inner thoughts and feelings, if one wished,
or to co ncentrate on the beauty of nature.
Some informants reported heightened sensation of skin to fine touch,
as well as sexual arousal. A senior traditional African healer, not
previously exposed to 'kougoed', tried it and announced that it
'relaxes the mind' and one's body feels 'light' the following day.
A white Namaqualand farmer, who has observed his shepherds and
labourers using 'kougoed', points out that it is not possible to
discern that they are intoxicated with it: they walk normally and
work as usual. The only sign that they have been using 'kougoed', he
says, is 'a sort of faraway look in their eyes'. Three first-time
users reported experiencing clouding of consciousness with doses
that caused intoxication. A horticulturist reported that he was once
stung by a bee while on a fieldtrip. He chewed on some 'kougoed'
(for the first time) in the hope that it would alleviate the pain.
The pain subsided rapidly but no intoxication was experienced.
Rood (1994) includes a number of anecdotes on Sceletium anatomicum.
A Mr. P. van Breda of Worcester reported that if enough is eaten, it
anaesthetizes the lower jaw sufficiently to enable a tooth to be
extracted painlessly. Mrs. Helena Marincowitz of Prins Albert
reported that San mothers used to simply chew the root and spit the
juice into the mouth of an infant, who would then sleep soundly for
a few hours. Mrs. Lettie van Niekerk of Karnieskroon reported that
it is an excellent carminative for stomach ailments and winds. Mr.
J.H. Cornelissen stated that Blacks from Queenstown and Khoisan from
Namaqualand use an infusion of the leaves of Sceletium tortuosum to
relieve pain and alleviate hunger.
6. Conclusion
It may be concluded from the evidence presented that 'kougoed' and
the Sceletium alkaloids show no hallucinogenic properties, but
rather are narcotic-anxiolytic. This and their strongly synergistic
interaction with other psychomimetics indicates a serious need for
thorough pharmacological investigations. Foremost amongst these
would be toxicity and mode of action, such as receptor binding. A
recent study has shown that although mesembrenone was considerably
less toxic to mouse fibroblasts that twenty-one amaryllidaceous
alkaloids tested in vitro, it was moderately effective against
cancer cells (Weniger et al., 1995).
According to the observations of plant gatherers, plants of
Sceletium tortuosum and Sceletium strictum are becoming increasingly
scarce. Dwindling natural populations point to possible
overexploitation. A resurgence of interest in Sceletium alkaloids
will serve to encourage cultivation of these plants, either in the
natural habitat, botanical gardens, or elsewhere, especially as
these taxa are reputedly easily grown (Schwantes, 1953).
Acknowledgements
The Board of Trinity College, Dublin for permission to reproduce
folio 116r of Simon van der Stel's Journal. Mrs. Estelle Potgieter,
Chief Librarian of the Mary Gunn Library, National Botanical
Institute is thanked for locating and supplying the rare, early
publications. Ms. Fiona Archer, Mr. Lodewyk Mories, Jap-Jap Klaase
and Gertijies Drukse are thanked for ethnobotanical data and field
participation. Dr. Hugh Glen, Pascale Hertz and Marthina Mössmer of
the National Botanical Institute are thanked for taxonomic
assistance and constructive criticism of the manuscript.
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