Agriculture Reference
In-Depth Information
Family —
Lythraceae
Common Names —
Pomegranate tree, grenadier (French)
African Names —
Arabic: roumamman-goulnar, rumman, rummani, ximani; Chagga: nguku-
maanga; Mpondo: mbona wesilungu; Swahili: mkoma manga
Description —
Pomegranate is one of the oldest drugs known. It was mentioned in the
Papyrus Ebers of Egypt written in about 1150 BC and was also included in many Ayurvedic texts.
Pomegranate of commerce consists of the stem and root of
Punica granatum
containing at least
0.4% and sometimes 1% of alkaloids, of which the anthelmintic pelletierine tannate is the most
important. It is a shrub, which often reaches a height of 2.5 cm, with quadrangular and somewhat
thorny stalks. The leaves are lanceolate, 4 to 6 cm. It bears red, solitary flowers 4 cm long. The fruits
are spherical and 10 cm in diameter and contain numerous reddish fleshy seeds. The plant is cited
in the first edition (Vol. 1) of the
African Pharmacopoeia
.
436
Ethnomedicinal Uses —
The plant has limited use in traditional medicine but is acclaimed as
a potent anthelmintic. The plant is an ingredient in the remedy for dysentery and chronic diarrhea.
The fruit rind is used in postpartum medication.
Constituents —
The most important compound found in the plant used to be the anthelmintic
alkaloid pelletierine, which has been isolated from the root, stem bark, and unripe but mature fruits.
Other alkaloids found in pomegranate include isopelletierine, pseudopelletierine, and methylisopel-
letierine. The ellagitannins punicalin, punicalagin, punigluconin, and punicacorteins A, B, C, and
D and casuarin are also found in the plant.
894
The rind of pomegranate, which was once used as food
flavor and sometimes added as an adulterant to the drug, does not contain the anthelmintic alkaloids
but yields gallotannic acid and other phenolic compounds. The presence of phenolic compounds,
such as anthocyanin,
895
in the leaves and fruits is considered of immense therapeutic importance.
An analysis of
P. granatum
juice with high-performance liquid chromatography with diode array
detection and tandem mass spectrometry analysis with positive and negative electrospray ionization
(HPLC-DAD-ESI
+/−
/MS
n
) powered by an ion trap yielded a total of 151 phenolics, consisting of
65 anthocyanin, anthocyanin-flavanol, and flavanol-anthocyanin adducts, including some unusual
cyanidin and pelargonidin trihexosides not previously described in natural extracts. Similarly, a
total of 86 nonanthocyanin phenolic components were also identified, 39 of them reported for the
first time in this juice.
896
Pharmacological Studies —
Pelleterine, the active constituent, possesses a specific action on
tapeworms but is ineffective against other intestinal parasites.
205
The alkaloids of pomegranate act
by causing the tapeworm to relax its grip on the intestinal walls, thereby making it possible to be
expelled by cathartics. Pomegranate and its alkaloids are not favored as an anthelminthic due to
their toxic effects, muscle cramps, and dizziness.
123
The extract of the flowers and the rind has been
shown to possess significant inhibitory activity against many bacteria
897
and some fungi.
898
The modern use of
Punica granatum
is not because of its anthelmintic principles but its anti-
oxidant activity. Differential solvent extracts of
Punica granatum
leaves (hexane, dichloromethane,
ethyl acetate, ethanol, and methanol) have been evaluated for antioxidant, anti-inflammatory, anti-
cholinesterase, and cytotoxic activities. TPC (8.8-127.3 mg gallic acid equivalent/g dry weight),
flavonoids (1.2-76.9 mg quercetin equivalent/g dry weight), tannins (63.7-260.8 mg catechin equiv-
alent/kg dry weight), and anthocyanins (0.41-3.73 mg cyanidin-3-glucoside equivalent/g dry weight)
of different extracts were evaluated. The methanolic extract presented a good IC
50
by DPPH and
ABTS assays (5.62 and 1.31 mg/l, respectively). The strongest 5-LOX, acetylcholinesterase, and
butyrylcholinesterase inhibition activities were obtained for the ethanol extract (IC
50
values of 6.20,
14.83, and 2.65 mg/l, respectively), and the best cytotoxic activity against MCF-7 cells was obtained
for the methanol extract (IC
50
= 31 mg/l). Although it is the fruits and juice of
P. granatum
that are
used as pharmaceutical antioxidants, the leaves could be a potential source of the active molecules
intended for applications in the pharmaceutical industry.
899
