ASHOKA Saraca asoca
Caesalpiniaceae
San:Asoka, Gatasokah; Hin:Asok, Asoka; Ben:Ashok; Mal:Asokam;
Tam: Asogam; Kan:Asokada, Aksunkara; Tel: Asokamu, Vanjalamu
Importance
Ashoka, the sacred tree of Hindus and Buddhists, possesses varied medicinal uses.
The bark is useful in dyspepsia, fever, dipsia, burning sensation, visceromegaly, colic, ulcers,
menorrhagia, metropathy, leucorrhoea and pimples. The leaf juice mixed with cumin seeds is used for
treating stomachalagia. The floweres are considered to be uterine tonic and are used in vitiated
conditions of pitta, syphilis, cervical adinitis, hyperdipsia, burning sensation, haemorrhoids, dysentery,
scabies in children and inflammation. The well-known Ayurvedic preparations are ”Ashokarishta”
and “Ashokaghrita”. Ashokarishta is prescribed in leucorrhoea, haematuria, menorrhagia and other
diseases of genitourinary system of females.
Distribution
Ashoka is found almost throughout India, except North-Western India, upto 750m. It is also
found in the Andaman Islands.
Botany
Saraca asoca (Roxb.) de Wilde. syn. S. indica auct. non Linn. is a medium sized evergreen
tree growing upto 9m height with numerous spreading and drooping glabrous branches. Leaves are
pinnate, 30-60cm long having 2-3 pairs of lanceolate leaflets. Flowers are orange or orange yellow,
arranged in dense corymbs and very fragrant. Fruits are flat black pods, leathery and compressed with
4 - 8 seeds/pod. Seeds are ellipsoid oblong and compressed. The bark is dark brown to grey or black
with a warty surface. The thickness varies from 5mm to 10mm. The entire cut surface turns reddish
on exposure to air. Polyalthia longifolia (Annonaceae) is equated with the name Asoka by some
(Kapoor & Mitra, 1979; Chunekar, 1982) and is often used as an adulterant of the genuine Asoka
bark or as a substitute (Warrier et al,1996).
Agrotechnology
Asoka grows well in areas with well distributed rainfall and in slightly shady areas. Asoka
requires soil rich in organic mater and moisture. The best season of planting is June-July. It is also
grown in summer, if irrigation facilities are available. The plant is seed propagated. Seeds are formed
usually during February-April. Seeds are collected when they are ripen and fall down and are sown
after soaking in water for 12 hours on the prepared beds. Seeds germinate within 20 days. The seeds
are then planted in polybags. 2-month-old seedlings from the polybags are used for transplanting.
Square shaped pits of 60cm depth are taken at 3m spacing and filled with topsoil, sand and dried
cowdung. On this the seedlings are planted. Application of FYM at 10kg/tree/year is highly beneficial.
Chemical fertilisers are not usually applied. Irrigation during summer months is essential. No serious
pests or diseases are generally noted in this crop. If properly cultivated, Asoka can be cut after 20
years and the bark collected. It is cut at a height of 15cm from the soil level. If given irrigation and
fertilisers, the cut wood will sprout again and harvested again after 5 years. This can be continued.
When it is difficult to cut the tree, the bark can be peeled off from one side first. When the bark
grows and cover that part, the other side can be peeled off. This is also continued (Prasad et al, 1997;
Karshakasree, 1998).
Properties and Activity
Flowers give β-sitosterol, flavonoids and flavone glycosides-quercetin, kaempferol- 3 - O-β-D-
glucoside, quercetin- 3 - O-β-D-glucoside. The anthocyanins present are pelargonidin-3, 5-diglucoside
and cyanadin-3, 5-diglucoside. Bark yields catechol and sterols-(24ζ)- 24 - methyl cholest- 5 - en- 3 β-ol,
(22E, 24ζ)- 24 - ethylcholesta-5, 22-dien- 3 β-ol and (24ζ)- 24 - ethyl cholest- 5 - en- 3 β-ol, a wax
containing n-alkanes, esters and free primary alcohols. Alcoholic extract and glycoside P 2 from stem
bark is oxytoxic. Aerial part is CNS active, hypothermic, CNS depressant and diuretic. Stem bark is
anticancerous, has spasmodic action on rabbit intestine and cardiotonic action in frog and dog. Seed is
antifungal. Stem bark is astringent, antileucorrhoeic, antibilious and uterine sedative. Flower is uterine
tonic, antidiabetic and antisyphilitic. Stem bark and flower is antibilious (Husain et al, 1992).