UITTREKSEL
Die proteininhoud van drie ligeenspesies uit die N amib-woestyn
is
deur middel van
die
konvensionele Kjeldahl-metode bepaal. Van
die
drie het Parmelia hottentotta
die
hoogste proteien-inhoud gehad (16,24%), gevolg deur Omphalodium convolutum
(14,42%)
en
Teloschistes capensis (13,45%). Suurhidrolise van
die
drie spesies het
fruktose, galaktose, glukose
en
die
"aminosuiker glukosamien opgelewer. Die hidroli-
saat het ook 'n verskeidenheid amino sure bevat.
INTRODUCTION
A considerable amount
of
work has been published on the chemical composition
of
the extracellular products
of
lichens. The chemistry, structure, properties and distri-
bution
of
these so-called
~chen
substances have been treated
in
detail by Asahina &
Shibata (1954), Culberson (1969, 1970) and Culberson, Culberson & Johnson (1977).
Several studies have also appeared on the chemistry
of
carbohydrates,
free
amino acids
and other intraceUular products. Reference
to
these products has been made by
Huneck (1973), Mosbach (1973) and Hale (1974).
Huneck
& Follmann (1971) reported on the occurrence of lichen substances
in
Telo-
schistes capensis (L.f.) Malme (salazinic acid, parietin) and Omphalodium convolu-
tum Hue (norstictic acid, stictic acid,
(+)
- usnic acid). The findings
of
these and
other authors regarding the occurrence of lichen products
in
other species indigenous
to South West Africa are listed by Culberson (1970) and Culberson
et al (1977).
Considerable lichen growth occurs
in
certain parts
of
the central and northern Namib
Desert. More information on their chemical composition seemed
of
interest
in
view
.
of
their role
as
primary producers of organic matter
in
such an arid environment. This
paper represents an effort to determine the total nitrogen content as
well
as
the amino
acid and carbohydrate composition
of
three lichen species from the Namib .Desert.
MATERIALS
AND
METHODS
Lichen
material
All
the lichens used
in
this investigation were obtained through the courtesy
of
th~.
Director,
SWA
Administration, Department
of
Nature Conservation and Tourism,
and collected
by
Mr.
J.
Jankowitz. Parmelia hottentotta Ach. (Plate 1) was f6und
approximately
35
km
east
of
Henties Bay. Omphalodium convolutum (Plate
2)
was
collected along the gravel road between Swakopmund anq Windhoek, approximately
15
km
from Swakopmund. Teloschistes capensis (Plate
3)
:was
collected on the gravel
flats approximately 3 km north
of
Wlotzka's Baken. \
The lichen material was thoroughly cleaned of adhering
soil
and rock particles.
\
34
Reproduced by Sabinet Gateway under licence granted by the Publisher (dated 2012)
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