A remarkable study by researchers at the
Department of Biological Sciences, College of Science and Technology,
Covenant University Ogun State in Nigeria showed that the local cherry
fruit, African star apple (Agbalumo, Udara) lowered blood sugar and
cholesterol, and could be useful in preventing and treating heart
diseases.
By Chukwuma Muanya
African star apple also known as Agbalumo (Yoruba), Udara (Igbo) in
Nigeria, is associated with the dry season and has been enjoyed over the
years by Nigerians as a fruit. But more studies are supporting its
folklore use for treating diseases such as diabetes, heart diseases and
drug resistant bacteria.
The
fruits are sub-spherical in shape, about 3cm in diameter, usually
5-celled and contain an edible, sweet fruit-pulp. This fruits are good
remedies for sore-throat, tooth-ache, constipation, and much more.
Photo: Olanrewaju Disu
Botanically called
Chrysophyllum albidum, white star apple
belongs to the Sapotaceae family. It is distributed throughout the
southern part of Nigeria. In Southwestern Nigeria, the fruit is called
agbalumo and popularly referred to as udara in Southeastern Nigeria.
Chrysophyllum albidum is a popular tropical fruit tree and widely
distributed in the low land rain forest zones and frequently found in
villages.
The fleshy pulp of the fruits is eaten especially as snack and its
fruit has been found to have higher contents of ascorbic acid than
oranges and guava. It is also reported as an excellent source of
vitamins, irons, flavours to diets. The seeds are also used for local
games or discarded.
Chrysophyllum albidum fruit is common in both urban and rural centres
especially during the months of December to April. The fruits are not
usually harvested from the trees, but left to drop naturally to the
ground where they are picked.
A recent study by researchers at the Department of Biological
Sciences, College of Science and Technology, Covenant University Ogun
State in Nigeria showed that the local cherry fruit, African star apple
(Agbalumo, Udara) lowered blood sugar and cholesterol, and could be
useful in preventing and treating heart diseases.
The study titled, “Effects of ethanolic leaf extract of Chrysophyllum
albidum G. on biochemical and haematological (blood-related) parameters
of albino Wistar rats” was published in African Journal of
Biotechnology.
Previous
studies indicate that the roots, barks and leaves of Chrysophyllum
albidum have been employed in folk medicine for the treatment of
diseases. The bark is used for the treatment of yellow fever and
malaria, while the leaf is used as an emollient and for the treatment of
skin eruption, stomachache and diarrhoea. The cotyledons from the seeds
of Chrysophyllum albidum are used as ointments in the treatment of
vaginal and dermatological infections in Western Nigeria.
The fruit pulp is rich in Vitamin C and iron and an excellent source
of raw material for industries. Tannins, flavonoids, terpenoids,
proteins, carbohydates and resins are the phytochemicals that have been
reported in Chrysophyllum albidum. Methanolic extract of the cotyledons
from the seeds of Chrysophyllum albidum led to the isolation of
eleagnine, tetrahydro- 2 -methylharman and skatole.
Eleagnine was found to be the main compound responsible for its
antimicrobial activity. Eleagnine was further shown to exhibit
anti-nociceptive, anti-inflammatory and antioxidant activities. The seed
cotyledon has been reported to possess anti-hyperglycemic (lowers high
blood sugar) and hypolipidemic (lower blood cholesterol) effects.
The researchers investigated the effect of oral administration of the
leaf extract of Chrysophyllum albidum G. on biochemical and
haematological parameters in albino rats for 16 days.
The researchers write: “In conclusion, the study has demonstrated
that the leaf extract of Chrysophyllum albidum may not cause any adverse
effect on the biochemical and haematological indices of
toxicity. Moreover, the extract was found to possess anti-platelet and
hypoglycemic (lowers blood sugar) properties and might be employed in
the management of myocardial infarction (heart attack) and diabetes
mellitus, respectively. Further investigation is needed to establish the
anti-platelet property of the extract.”
Another study by researchers at the Forest Research Institute,
Ibadan, Oyo State, showed that star apple leaves exhibited strong
antibacterial activity against common bacteria isolates.
The study titled, “Antibacterial activity and phytochemical screening
of Chrysophyllum albidum leaves” was published in Asian Journal of Food
and Agro-Industry.
Culturally,
African star apple (Agbalumo) (Udara) seeds are threaded as anklets in
dancing in Nigeria. Also, young people, especially boys, use the seeds
to play a peculiar out-door game. Photo credit: Olanrewaju Disu
Preliminary phytochemical screening of Chrysophyllum albidum leaves
for secondary metabolites showed the presence of tannin, anthraquinone
and cardiac glycosides in the plant samples. The samples were devoid of
saponin, alkaloids and reducing sugars.
The researchers write: “Biological actions are primarily due to these
components in a very complicated concert of synergistic or antagonistic
activities. Mixtures of such chemicals show a broad spectrum of
biological effects and pharmacological properties.
“The antimicrobial properties of the plant observed in this study
could be attributed to the presence of tannin, anthraquinone and cardiac
glycosides. The results showed that the test organisms were susceptible
to the water extracts based on their zones of inhibition, which ranged
from 10 to 27 mm. Escherichia coli showed the highest susceptibility of
27. All the organisms were sensitive at all concentrations except
Escherichia coli, which was not sensitive at 125 µg/mL and 250 µg/mL.
The least activity 10 mm was detected at 125 µg/mL concentration with.
“The methanolic extract of Chrysopyllum albidum leaves exhibited some
antimicrobial activity against all the microorganisms tested as
assessed by zones of inhibition that ranged from (25±0 to 35±0.40mm).
Escherichia coli had the highest susceptibility at 250 µg/mL
concentrations with zone of inhibition of 35±0.40 mm. There was increase
in the zone of inhibition for Escherichia coli from 30 (±0.15) mm at
125 µg/mL to 35 (±0.40) mm and 35±0.21 at 250 µg/mg and 500 µg/mL
respectively. Salmonella typhi and Shigella spp had a zone of inhibition
of 35 mm at all concentrations except at 500 µg/mg where Shigella spp.
which had zone of inhibition of 30 (±0.30) mm.
“These results suggest that water and methanolic extracts from the
leaves of Chrysophylum albidum may contain active agent(s). This
provides the basis for their folkloric use as cure for some human
ailments like skin infection, diarrhoea and stomachache, which are as a
result of infections and inflammatory reactions. It is suggested that
more research be conducted to further isolate, identify, characterise
and elucidate the bioactive compounds from Chrysophylum albidum.
“In conclusion, the result of this study justifies the traditional
uses of the leaves of Chrysophylum albidum for therapeutic purposes. The
findings could also be of commercial interest to both pharmaceutical
companies and research institute in the production of new drugs.”
Researchers have also studied the nutritional value and mineral
contents of Chrysophyllum albidum fruit. According to the study
published in Journal of the Science of Food and Agriculture, fresh fruit
samples, both untreated and treated with 2,4-dichlorophenoxyacetic
acid, were investigated.
InformAfrica
“I
believe good people who will be able to manage it (Nigeria), maybe
later. But the earlier we are there, the better and I am sure we will be
there,” the former president said.
