Michael T. Smith (a), Neil R. Crouch
(b), Nigel Gericke (c), Manton Hirst (d)
(a) Botany Department, University of Natal, Private Bag X01, Scottsville,
3209 Pietermarilzburg, South Africa
(b) National Botanical Institute, Ethnobotany Section. Natal Herbarium,
Botanic Gardens Road, Durban 4001, South Africa
(c) TRAMED, Department of Pharmacology, Medical School, University
of Cape Town, Observatory 7925 South Africa
(d) Kaffrarian Museum, P.O. Box 1434. Kingwilliam's Town 5600, South
Aftica
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.
Keywords: Sceletium; Mesembryanthemaceae; Alkaloids;
Oxalates; Hallucinogens; Anxiolytic agent
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.) Qu?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 ?er 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 M?er of the National Botanical Institute are thanked
for taxonomic assistance and constructive criticism of the manuscript.
References
Aiton. W.T. (1811) Hortus Kewensis
or, A Catalogue of the Plants Cultivated in the Royal Botanic
Garden at Kew. Vol. Ill. Longman, Hurst, Rees, Orme, and Brown,
London.
Allison, M.J., Dawson, K.A., Cook,
H.M. and Mayberry, W.R. (1985) Oxalobacter formigenes gen. nov.,
sp. nov: oxalate-degrading anaerobes that inhabit the gastrointestinal
tract. Archives of Microbiology 141, 1-7.
Argenzio, R.A., Liacos, J.H. and
Allison, MJ. (1988) Intestinal oxalate-degrading bacteria reduce
oxalate absorbtion and toxicity in guinea pigs. Journal of Nutrition
118, 787-792.
Arridt, R.R. and Kruger, P.E.J. (1970)
Alkaloids from Sceletium joubertii L. Bolus: the Structure of
joubertiamine, dihydrojoubertiamine and dehydrojoubertiamine.
Tetrahedron Letters 37, 3237-3240.
Arnold, T.H. and de Wet, B.C. (1993)
Plants of Southern Africa: Names and Distribution. Memoirs of
the Botanical Survey of South Africa, No. 62, National Botanical
Institute, Pretoria.
Barz, W. and K6ster, J. (1981) Turnover
and degradation of secondary (natural) products. In: P.K. Stumpf
and E.E. Conn (Eds.), The Biochemistry of Plants: a Comprehensive
Treatise. Vol. 7, Academic Press, New York, pp. 35-84.
Bastida, L, Viladomat, F., Llabres,
J. M., Ramires, G., Codina, C. and Rubiralta, M. (1989) Narcissus
alkaloids, VIII mesembrenone: an unexpected alkaloid from Narcissus
pallidulus. Journal of Natural Products 52, 478-480.
Bittrich, V. (1986) Untersuchungen
zu Mermalsbestand, Gliederung und Abgrenzung der Unterfamilie
Mesembryanthemoideae (Mchembryanthemaceae Fend) Mitteilungen
aus den Instit? Allemeine Botanik (Hamburg) 21, 5-116.
Bolus, H.M.L. (1928) Notes of Mesembrianthemum
and Some Allied Genera with Descriptions of a Hundred New Species.
Part I. Bolus Herbarium, University of Cape Town. The Speciality
Press, Cape Town.
Burchell, W.J. (1822) Travels in
the Interior of Southern Africa. Vol. 1. Longman, Hurst, Rees,
Orne and Brown, London.
Burchell, W.J. (1824) Travels in
the Interior of Southern Africa. Vol. 11. Longman, Hurst, Rees,
Orne and Brown, London.
Daniel, S.L., Hartmann, P.A. and
Allison, MJ. (1987) Microbial degradation of oxalate in the
gastrointestinal tracts of rats. Applied and Environmental Microbiology
53, 1793-1797.
Dobkin de Rios, M. (1990) Hallucinogens:
Cross Cultural Perspectives. Prism-Unity, Dorset, U.K.
Elphick, R. (1977) Kraal and Castle:
Khoikhoi and the Founding of White South Africa. Yale University
Press, London.
Emboden, W. (1979) Narcotic Plants.
MaeMillan, New York.
Fourie, T.G., Swart, I. and Snyckers,
F.O. (1992) Folk medicine: A viable starting point for pharmaceutical
research. South African Journal of Science 88, 190-192.
Gartz, J., Reid, D., Smith, M.T.
and Eicker, A. (1994) Psilopybe natalensis sp. nov. The first
indigenous blueing member of the Agaricales in South Africa.
Integration (in press).
Gunn, M.G. and Codd, L.E. (1981)
Botanical Exploration of Southern Africa: an Illustrated History
of Early Botanical Literature on the Cape Flora, Biographical
Accounts of the Leading Plant Collectors and their Activities
in Southern Africa from the days of the East India Company until
modern times. Balkerna, Cape Town.
Guzinan, G. (1983) The Genus Psilocybe.
Beiliefte Zur Nova Hedwigia 74, 1-439. Kramer, Vaditz.
Hanson, C.F., Frankos, V.H. and Thompson,
W.O. (1989) Bioavailability of oxalic acid from spinach, sugar
beet fibre and a solution of sodium oxalate consumed by female
volunteers. Food Chemistry and Toxicology 27, 181~184.
Hartmann, M.E.K. (1991) Mesembryanthema.
Contributions from the Bolus Herbarium 13, 75-157.
Haworth, A. H. (1794) Observations
on the Genus Mesembryanthemum, in Two Parts. J. Barker, B. and
J. White, London.
llcgtiauer, R. (1988) Biochemistry,
distribution and taxonomic relevance of higher plant alkaloids.
Phytochemistry 27, 2423-2427.
Herre, H. (1971) The Genera of the
Mesembryanthemaceae. Tafelberg Publishers, Cape Town.
Jacobsen, H. (1960) A Handbook ofSucculent
Plants. Vol. III. Mesembryanthemums (Ficoidaceae). Blandford
Press, London.
Jeffs, P.W., Allmann, G., Campbell,
H.F., Farrier, D.S., Ganguli, G. and Hawks, R. L. (1970) Alkaloids
of Sceletium species. 111. The structures of four new alkaloids
from Sceletium strictum. Journal of Organic Chemistry 35, 3512-3518.
Jeffs, P.W., Archie, W.C., Hawks,
R.L. and Farrier, D.S. (197 1) Biosynthesis of mesembrine and
related alkaloids: the arnino acid precursors. Journal ofthe
American Chemical Society 93, 3752~3758.
Jeffs, P.W., Capps, T., Johnson,
D.B., Karle, J.M., Martin, N.H. and Rauckman, B. (1974) Sceletiton
alkaloids. VI. Minor alkaloids of Sceletium namaquense and Sceletium
strictum. Journal of Organic Chemistry 39, 2703-2709.
Jeffs, P.W., Karle, LM, and Martin,
N.H. (1978) Cinnamic acid intermediates as precursors to mesembrine
and some observations on the late stages in the biosynthesis
of the mesembrine alkaloids. Phylochemistry 17, 719-728.
Juritz, C.F. (1906) Kaffir beers,
their nature and composition. Cape Agricultural Journal, 28,
35-47.
Kellerman, T.S., Coetzer, LA.W. and
Naude, T.W. (1988) Plant Poisonings and Mycotoxicoses of Livestock
in Southern Africa. Oxford University Press, Cape Town.
Kolben, P. (1738) The Present State
ofthe Cape ofGood Hope. Vol, 1, 2nd ed. G. Medley (trans.) W.
Innys and R. Matiby, London.
Laidler, P.W. (1928) The magic medicine
of the Hottentots. South African Journal of Science 25, 433-447.
Lewis, W.H. and Elvin-Lewis, P.F.
(1977) Medicinal Botany: Plants Affecting Man's Health. Wiley,
New York.
Lewis-Williams, I.D. (1981) Believing
and Seeing.. Symbolic Meanings in Southern San Rock Paintings.
Academic press, London.
Libert, B. and Franceschi, V.R. (1987)
Oxalate in crop plants. Journal of Agricultural and Food Chemistry
35, 926~938.
Marloth, R. (1913) The Flora of South
Africa with Synoptical Tables ofthe Genera ofHigher Plants.
Vol. I. William Wesley & Son, London.
McKenna, D.J., Towers, G.H.N. and
Abbott, F. (1984) Monoarnine oxidase inhibitors in South American
hallucinogenic plants: tryptarnines and 0-carboline constituents
of ayahuasca. Journal of Ethnopharmacology 10, 195-223.
Meiring, I. (r898) Notes on some
experiments with the active principle of Mesembryanthemum tortuosum.
Transactions of the South African Philosophical Society 9, 48-50.
Nienaber, G.S. and Raper, P.E. (1977)
Toponymica Hottentolica. (Volume H-Z). HSRC, Pretoria.
Paterson, W. (1789) A narrative offourjourneys
into the country of the Hottentots and Caffraria. London.
Popelak, A. and Lettenbauer, G. (1968)
The mesembrine alkaloids. In: R.H.F. Manske (Ed.), The Alkaloids.
Vol. 9. Academic Press, New York, pp. 467-482.
Raper, P.E. and Boucher, M. (Eds.)
(1988) Robert Jacob Gordon. Cape Travels, 1777 to 1786. Vol.
1. The Brenthurst Press, Houghton, South Africa.
Rimington, C. and Roets, G.C.S. (1937)
Notes upon the isolation of the alkaloidal constituent of the
drug 'channa' or 'kougoed' (Mesembryanihemum anatomicum and
Mesernbryanthemum tortuosum). Onderstepoort Journal of Veterinary
Science and Animal Industry 9, 187-191.
Rood, B. (1994) Uit die Veld-Apteek.
Tafelberg, Cape Town.
Rowley, G.D. (1978) Caryophyllidae.
In: V.E. Heywood (Ed.), Flowering Plants of ihti World. Oxford
University Press, UK, pp. 63-67.
Schapera, 1. (1963) The Khoisan Peoples
of South Africa. Routledge, London. '
Schultes, R.E. (1970) The botanical
and chemical distribution of hallucinogens. Annual Review of
Plant Physiology 21, 571-598.
Schultes, R.E. (1976). Indole Alkaloids
in Plant Hallucinogens. Planta Medica 29, 330~342.
Schultes, R.E. (1977) The botanical
and chemical distribution of hallucinogens, In: B.B. Du Toit
(Ed.), Drugs, rituals and altered states of consciousness, A.A.
Balkerna, Rotterdam, pp. 25-55.
Schultes, R.E. and Farnsworth, N.
(1980) Ethnomedical, botanical and phytochemical aspects of
natural hallucinogens. Botanical Museum Leaflets of Harvard
University 28, 123-214.
Schultes, R.E. and Hofrnann, A. (1979)
Plants of the Gods.. Origins of Hallucinogenic Use. Hutchinson,
London.
Schwantes, G. (1953) The cultivation
of the Mesemhryanthemaceae. Blandford Press, London.
Smith, C.A. (1966) Common names of
South African plants. Botanical Survey Memoir No. 35, Botanical
Research Institute, Pretoria.
Smith, R.L., Strohmaier, F.E. and
Oremland, R.S. (1985) Isolation of anaerobic oxalate-degrading
bacteria from freshwater lake sediments. Archives of Microbiology
141, 8-o.
Smith, T.A. (1977) Tryptamine and
related compounds in plants. Phylochemistry 16, 171-175.
Snyckers, F.O., Strelow, F., and
Weichers, A. (1971) The structures of partial racemic Sceletium
alkaloid A4 and tortuosamine, pyridine alkaloids from Sceletium
tortuosum N.E.Br. Chemical Communications (The Journal of the
Chemical Society, Section D), 1467-1469.
Stevens, R.V. (1977) Alkaloid synthesis.
In: J. ApSimon (Ed.), The Total Synthesis of Natural Products.
Wiley, New York, pp. 439-554.
Sutikno, A.I., Suherman, D. and Tangendjaja,
B. (1987) A screening method for total oxalate determinations
in plant material by gas chromatography. Journal of the Science
of Food and Agriculture 39, 233-238.
Steyn, D.G. (1934). The Toxicology
of Plants in South Africa (Together With a Consideration of
Poisonous Foodstuffs and Fungi). Central News Agency Ltd., London.
Thunberg, C.P. (1794) Travels in
Europe, Africa and Asia, made between the years 1770 and 1779.
Vol. II. W. Richardson and J. Egerton, London.
Waterhouse, 0. (1932) Simon van der
Stel's Journal of his Expedition to Namaqualand 1685-6. Longmans,
Green, and Co., London.
Waterhouse, G., De Wet, G.C. and
Pheiffer, R.H. (1979) Simon van der Stel's Journey to Namaqualand
in 1685. Human and Rousseau, Cape Town.
Watt, J. M. and Breyer-Brandwijk,
M.G. (1932) The Medicinal and Poisonous Plants of Southern Africa.
Livingstone, Edinburgh.
Watt, J.M. and Breyer-Brandwijk,
M.G. (1962) The Medicinal and Poisonous Plants of Southern and
Eastern Africa 2nd ed. Livingstone, London.
Weil, A.T. and Davis, W. (1994) Bufo
alvarius: a potent hallucinogen of animal origin. Journal of
Ethnopharmacology 41, 1-8.
Weniger, B., Italiano, L., Beck,
J-R, Bastida, J., Bergonon, S., Codina, C., Lobstein, A. and
Anton, R. (1995) Cytotoxic activity of Amaryllidaceae alkaloids.
Planta Medica 61, 77-79.
