TERMINALIA SERICEA GENERAL DESCRIPTION

TERMINALIA SERICEA
GENERAL DESCRIPTION
Scientific name
with author
Terminalia sericea Burch. ex DC.
Plant photo – live
plant
Synonyms
Terminalis angolensis O.Hoffm.; Terminalia fischerii Engl.; Terminalia nyassensis Engl.; Terminalia
brosigiana Engl. & Diels; Terminalia velutina Rolfe; Terminalia bubu De Wild.
Family
Combretaceae
Vernacular/
traditional/
regional names
Vaalboom, silwerboom, bloubos, bosvaal, sandvolbos (Afrikaans); silver cluster-leaf, silver terminalia
(English); umangwe (Ndebele); mangwe, mukonono, mususu, mutabvu (Shona); mususu (Venda);
amangwe (Zulu)
Botanical
description
Terminalia sericea is a small to medium-sized deciduous tree which usually grows about 5-8 metres high. It
has an erect trunk and a wide spreading crown. T. sericea has reddish-brown branches. The leaves are
crowded at the ends of branches, narrowly obovate-elliptic with smooth margins, blue-green above, paler
below, densely covered in silvery hairs. The blue-silvery leaves make it very easy to identify. It flowers
mostly in September–January. The flowers are in axillary spikes and are pale yellow to creamy white.
Flowers have an unpleasant smell. The fruit is an oval nut surrounded by two broad papery flat wings. The
fruits are often parasitized and form deformed masses of thin round galls. Terminalia species are closely
related to Combretum species but the latter have four or more wings on the fruit.
Reference
South African National Biodiversity Institute. (2012). Terminalia sericea Burch. ex DC.
bhttp://www.plantzafrica.com/planttuv/terminaliasericea.htm
Geographical
distribution
T. sericea occurs on sandy soil in the savannah areas in northern South Africa.
Distribution map
ETHNOBOTANICAL INFORMATION
Medicinal uses
T. sericea is important in traditional medicine. Root decoctions and infusions are used in traditional
medicine to treat venereal diseases, diarrhoea, dysentery, colic, pneumonia, cough, skin diseases,
schistosomiasis, gonorrhoea and problems with menstruation, and applied as an eye wash to treat
trachoma and ophthalmia. Roots are also used as an emetic.
Pulverized bark is applied externally to wounds. Ground bark is also eaten mixed with mealie meal to treat
diabetes.
Leaf extracts serve to treat diarrhoea and stomach complaints, and a leaf infusion taken to treat cough.
Pulverized leaves are applied as a dressing to wounds. In case of bleeding, a paste can be made by cooking
the leaves in water and placing them on the wounds. Use of dried fruit for tuberculosis is also recorded.
References
Nkobole, N.K. (2009). Antidiabetic activity of pentacyclic triterpenes and flavonoids isolated from stem bark
of Terminalia sericea Burch. Ex DC. Thesis, University of Pretoria, South Africa.
Pujol, J. (1990). Naturafrica – the herbalist handbook. Jean Pujol Natural Healers’ Foundation, Durban.
Watt, J.M. and Breyer-Brandwijk, M.G. (1962). The medicinal and poisonous plants of southern and eastern
Africa. 2nd ed. Livingstone, London.
QUALITY STANDARDS
Macroscopial
Deciduous shrub or small to medium-sized tree, usually up to 8 metres tall; bole straight or crooked, up to
50(–100) cm in diameter; bark surface cream-coloured to grey-brown, deeply grooved; crown layered,
with horizontal branches; branchlets red-brown to purplish, with peeling bark, silky hairy when young.
Leaves arranged spirally, clustered near ends of branchlets, simple and entire; stipules absent; petiole up
to 1.5 cm long; blade narrowly elliptical-obovate, 5–13 cm × 1–4.5 cm, cuneate at base, rounded to shortacuminate at apex, silvery silky hairy especially when young, pinnately veined with 5–8(–13) pairs of
indistinct lateral veins. Inflorescence an axillary spike 5–12 cm long, densely silky hairy; peduncle 2.5–5
cm long. Flowers bisexual or male, regular, 4–5-merous, greenish white; receptacle spindle-shaped, c. 5
mm long; sepals triangular, c. 2 mm long; petals absent; stamens usually 10, free, c. 4 mm long; disk
annular, hairy; ovary inferior, 1-celled, style 3–5 mm long. Fruit a winged nut, broadly elliptical in outline,
3–4 cm × 1.5–2.5 cm including the wing, stipe up to 0.5 cm long, pinkish or purplish brown, finely hairy,
indehiscent, 1-seeded. T. sericea grows slowly. Annual elongation of the bole results in a layered crown.
Flowers develop together with young leaves, usually in September–November. The flowers have a strong
and unpleasant smell, and are probably pollinated by flies. Fruits ripen 3–5 months after flowering, but
they may remain on the tree for up to 1 year.
Reference
Lemmens, R.H.M.J. (2009). Terminalia sericea Burch. ex DC. In: Lemmens, R.H.M.J., Louppe, D. & OtengAmoako, A.A. (Eds.). Prota 7(2): Timbers/Bois d’œuvre 2. PROTA, Wageningen, Netherlands.
http://database.prota.org/PROTAhtml/Terminalia%20sericea_En.htm
Microscopial
CHEMICAL CONSTITUENTS
Chemical
constituents –
compounds diagrams
Chemical
constituents –
compounds description
Anolignan B is the main bioactive compound isolated from the roots. Several pentacyclic triterpenoids, of
which sericic acid and sericoside are the major constituents, have been isolated in roots. Roots also contain
hydroxystilbene glycoside, the triterpenoid arjunglucoside, termilignan B and arjunic acid. A stilbene
glycoside, resveratrol-3-O-β-rutinoside, and resveratrol have been isolated from an ethanol extract of the
root bark.
Terminoic acid has been isolated as one of the antibacterial compounds from leaves. Nerifolin, a glycoside,
has been isolated from the tree. Galls have been found to contain 10.2% tanning matter. Gum
polysaccharides contain galacturonic, glucuronic and 4-0-methylglucuronic acids and galactose, arabinose,
rhamnose and xylose.
References
Hutchings, A., Scott, A.H., Lewis, G. and Cunningham, A.B. (1996). Zulu Medicinal Plants: an inventory.
Natal University Press, Pietermaritzburg.
Kruger, J.P. (2008). Isolation, chemical characterization and clinical application of an antibacterial
compound from Terminalia sericea. Ph.D. thesis, University of Pretoria, South Africa.
Chemical
constituents –
organoleptic
properties
The flowers have a strong and unpleasant smell. Root decoctions taste very bitter.
Chemical
constituents –
TLC / HPLC / GC
Chemical
constituents –
NIR Spectroscopy
image
Chemical
constituents –
NIR
The triterpenoids sericoside and arjunglucoside have been isolated from the roots and stem bark without
any biological assays. Terminoic acid was isolated as one of the antibacterial compounds from leaves, and
anolignan B from the roots. A stilbene glycoside, resveratrol-3-O-β-rutinoside, and resveratrol have been
isolated from an ethanol extract of the root bark.
Purity tests /
Requirements
TLC, HPLC and GC are used.
Assay
Not yet available.
USAGE
Plant part used
The roots are mainly used, sometimes also the stem bark and leaves.
Plant part used
photograph
Dosage forms
Pharmacology/
bioactivity
Anolignan B is a bioactive compound isolated from the roots. It showed activity against both gram-positive
and gram-negative bacteria, as well as anti-inflammatory activity. Root extracts showed significant antiHIV-1 properties. Root extracts are particularly active against the bacteria Staphylococcus aureus and
Streptococcus pyogenes and against the fungi Candida albicans, Candida glabrata and Cryptococcus
neoformans. The triterpenoids and saponins are well known for their antimicrobial and anti-inflammatory
activity. The pentacyclic triterpenoid sericic acid has been isolated from the roots, as well as its glycoside
sericoside. Root extracts and sericic acid have anti-inflammatory and wound-healing properties, and
showed antibacterial and antifungal activities. Sericoside has anti-inflammatory activity, whereas strong
lipolytic activity has also been suggested. The results from tests support the ethnomedical use of the roots.
However, caution is needed because in Tanzania several cases of death after application of root extracts
have been recorded. In tests root extracts were toxic to brine shrimps. Root extracts showed strong
cytotoxic effects against several human cancer cell lines.
Sericic acid and sericoside have shown anti-ulcer, anti-inflammatory and cicatrising activity.
Nerifolin, a glycoside isolated from the tree, inhibits fibroblastic outgrowth in aneural explanted heart tissue
in vitro and inhibits the pulsation rate in a dilution of 1:700 or higher.
Methanol extracts of the leaves showed strong in-vitro activity against HIV-1 reverse transcriptase.
The anti-diarrhoeal effects may be due to tannins.
Roots are reputed to be poisonous. Potential known toxins include tannic acid, saponin and hydrocyanic
acid.
References
Eldeen, I.M.S., Elgorashi, E.E., Mulholland, D.A. and van Staden, J. (2006). Anolignan B: A bioactive
compound from the roots of Terminalia sericea. Journal of Ethnopharmacology, 103(1):135-138.
Hutchings, A., Scott, A.H., Lewis, G. and Cunningham, A.B. (1996). Zulu Medicinal Plants: an inventory.
Natal University Press, Pietermaritzburg.
Kruger, J.P. (2008). Isolation, chemical characterization and clinical application of an antibacterial
compound from Terminalia sericea. Ph.D. thesis, University of Pretoria, South Africa.
Masoko, P. (2007). Characterization of antifungal compounds isolated from Combretum and Terminalia
species (Combretaceae).Thesis, University of Pretoria, South Africa.
Nkobole, N.K. (2009). Antidiabetic activity of pentacyclic triterpenes and flavonoids isolated from stem bark
of Terminalia sericea Burch. Ex DC. Thesis, University of Pretoria, South Africa.
Contraindications
Adverse
reactions
Roots are reputed to be poisonous.
Reference
Watt, J.M. and Breyer-Brandwijk, M.G. (1962). The medicinal and poisonous plants of southern and eastern
Africa. 2nd ed. Livingstone, London.
Precautions
Dosage and
preparation
Traditionally, root decoctions and infusions are taken orally and applied externally. Hot water decoctions of
the roots are used for diarrhoea, and to relieve colic pains. Roots steeped in water for 1 hour are used for
trachoma. A tea is made from roots for skin diseases and coughs. Enemas of root decoctions are used for
menstrual cramps. For headaches and general body weakness, root is powdered and swallowed with food.
For pneumonia roots are boiled in water for a hot fomentation. The powdered root bark is taken with maize
meal for diabetes. Leaf infusions are used for chest ailments and diarrhoea. Stem bark or leaves are
applied externally to wounds and burns. In case of bleeding, a paste can be made by cooking the leaves in
water and placing them on the wounds.
References
Hutchings, A., Scott, A.H., Lewis, G. and Cunningham, A.B. (1996). Zulu Medicinal Plants: an inventory.
Natal University Press, Pietermaritzburg.
Watt, J.M. and Breyer-Brandwijk, M.G. (1962). The medicinal and poisonous plants of southern and eastern
Africa. 2nd ed. Livingstone, London.
Source References
Brendler, T., Eloff, J.N., Guri-Fakim, A. and Phillips, L.D. eds. (2010). African herbal pharmacopoeia. Association for African
Medicinal Plants Standards, Mauritius.
Van Wyk, B-E., van Oudtshoorn, B. and Gericke, N. (2009). Medicinal plants of South Africa. 2nd ed. Briza, Pretoria.
`