Shorea robusta Gaertn. F. (SALA)

It is extensively used in the classical literature in the management of Kushtha (skin diseases) and Prameha (Diabetes). The resin is also used in bleeding piles (Rakta Arsas) and dysentery (Rakta PravŒhikŒ/Rakta Atisara). The Laghu Trayi texts and other Nighantus also described it elaborately.

Controversy and identification– For quite sometime there was confusion among the practitioners regarding identity of Sala, Sarja and Asvakarna. Caraka mentioned Sala, Sarja, Asvakarna and Ajakarna under Kaiyadeva Nighantu. Both Caraka and Sushruta quoted its resin as Sarja Rasa. The synonym Sala niryasa is used in Dhanwavtari Nighantu and Raja Nighantu. In Dhanvantari Nighantu two varieties viz., Sala & Sarja (Sarja Yugma) are described. Bhavamisra equated Sala and Sarja to Asvakarna and Ajakarna respectively.

Few years ago NBRI, Lucknow evaluated the samples of dammers sold in Indian market under the name of chunduras and Ral and analyzed them. They found that chunduras and Ral are the exudates of Shorea and Vateria species respectively (Khan. G. & Farooqi, 1994)1.

(i)     Asvakarna      =       Sala bheda (CP- C.S.Su. 25/49)

(ii)    Ajakarna         =       Sala bheda (GN- C.S.Vi. 8/122)

(iii)   Asana             =       P¶ta Sala (GN- C.S. Vi 8/122)

(iv)   Sala                =       Sarja bheda (DL- S.S.Ut. 17)

(v)    Sallaki            =       Sala (DL- S.S.Su.38)

Different Varieties– Direct reference about different varieties of Sala are not available. Bhavamishra’s Sarja yugma consists of Sala and Sarja. Apart from these two, Asvakarna and Ajakarna are to be identified . Therefore the botanical sources for the four trees shall be:

(i)      Sala               =     Shorea robusta Gaertn.

(ii)     Sarja             =     Vateria indica Linn.

(iii)    Asvakarna     =     Dipterocarpus alatus Roxb.

(iv)    Aja KarÄa     =     Shorea tumbuggaia Roxb.

It is important to note that all these trees yield resinous gums. Hence to avoid confusion, term sala niryasa and Sarja niryas are to be specifically used to denote resins of shorea robusta and vateria indica in future.

Botanical description– A deciduous tree with dark brown bark. Leaves– 10-30 x 5-18 cm., ovate-oblong, acuminate, coriaceous, cordate base, petiole 1.2-2cm long; Flowers– 1.2 cm long, yellowish, in terminal and axillary racemose panicles 7.5-23 cm, long; calyse- tubular, grey, tomentose outside, Petals narrow-oblong tolanceolate, silky- tomentose outside. Stamens upto 50, shorter than the petals, ovary 3-called. Fruit– 1.2 cm long, ovoid acute andindehisent. Seed ovoid, flesty with unequal cotyledons. Distribution– It has two main regions of distribution, one on the north and the other on the south of the Gangetic plain. It is mainly found in Kangra dist. Of Himachal Pradesh, Ambala dist. Of Haryana Darrang dist. Of Assam. To the south of Ganges, it is distributed from western parts of west bengal, Orissa and Visakhapatnam dist. Of Andhra Pradesh. It is also found in Chhindwara & Hoshangabad districts of Madhya Pradesh.

Pharmacognostic studies– Interlocking of fibres produces a ribbon grain effect, which is very characteristic of Sal. The width of alternating bands are more or less parallel or oblique to the axis of the log (pearson & Brown, I, 112; Indian Woods, I, 147).

The sapwood, is pale brownish white when fresh, but often turns black afterwards due to fungus attack. Heartwook is pale brown when first exposed but turns dark reddish brown with age. The transitional zone between the sapwood and heart wood is called as “kuch-pucca heartwood” to distinguish it from the true heart wood. Huge quantities of Sal bark are available during the conversion of the logs.

Chemical constituents– Sal bark, along with leaves and twigs, is a promising tanning material. The spray-dried aqueous extract of bark consists of 39.6% of tannins (pyrogallol type). Oleanolic acid is also found in the Bark (Howes, 1953, & Satyavati et al; 1967). Benzofuranshoreaphenal is found in the bark (Phytochem. 1992,31,2561). Sal resin (oleoresin known as Sal Dammar) on dry ditstillation yields and essential oil (Chua oil). Epi- taraxastanonol, β sitosterol, hydroxyanone, dam-marenediol II, dipterocarpol, dammarenolic acid, ighant acid and amyrin are isolated from resin (Ind. Drugs, 1989, 26, 146). Ursolic acid, ursaldehyde from resin (Phytochem., 1993, 32, 466 & 1994, 35, 1073). Bergenin and hemicellulose are isolated from the plant (Ind. Drugs, 1989, 26, 574 & Orient. J. Chem. 1989, 5, 258). Fat from nuts contained cis-9-10 epoxystearic acid (Chem. Ind. 1972, 805). Corlagin, ellagic, chebulic and gallic acids are isolated fro seeds (Leathre Sci. 1977, 24, 243). A new phenolic acid- shorbic acid is found in the seeds (fitoterapia 1979, 50, 7). A new flavone glycoside is reported from the seeds (fitoterapia 1999, 70, 6)

Part Used– The bark, sap wood, heartwood, resin, oil, seeds and seed oil are all used medicianally.

The resin is used in the indigenous system of medicine as an astringent and is given in dirarrhoea and dysentery. It is also used as an ingredient of ointments for skin diseases and in ear troubles (W.I. Vol. IX p. 320)

Chua oil is also used as antiseptic for skin diseases and for ear problems.

Sal flowers are produced in abundance and yield plenty of honey. Sal wood has high timber value. Sal leaves are used for ‘beedi’ making in Assam, west Bengal & Orissa.

Dosage– Decoction of bark- 50 to 100 ml

powder of resin- 1-3 g.

Research –

(1) The non-phenolic portion of the Chua oil- is reported to have a depressing effect on the CNS while the phenolic portion is less effective [kar & Menon, East, pharm, 12 (13a): p. 53, 1969].

(2) An herbal cream (Herbinol) consisting of S. robusta is reported to be bactericidal as well as bacteriostatic (Pandya K.K. et al; 1989).

• Effect of a mixture of ethanolic extracts of five plants (Plumbago rosea, Borassus flabellifer, Carica papay (male), Dolichos lab-lab and Shorea robusta) is studied on metabolism of glycogen, of composite root extract (CRE) was dose dependent. Adminstration of 250mg/kg did not induce significant changes in the biochemical profiles, while the other two doses i.e., 500mg/kg/day and 100mg/kg/day and 1000mg/kg/day induced changes of the glycogen, protein and RNA level in uterus ighan all phases of the estrous cycle and the values statistically significant. The levels of these biochemical companents decreased in the uterus of CRE treated rats. The results showed that this herbal preparation induces biochemical changes in uterus of albino rats (Sharma H.N.& Mahanta H.C., 2001).

• 52 patients of leucorrhea (18-15 years), were given Kungi libparpam, resin of S. robusta 1g/day in two divided doses. Kadukkai (T. Chebula) decoction was used for vaginal douche. Clinical and pathological assessements were carried out once in ten days. The response was 50% on the 10^th day, 80% on the 20^th day and 100% after the 30 days of treatment. Out of 52 cases, 12 were infected with Trichomonas vaginalis were also curued. 5 cases of cervical erosion included in this trial, showed healing of erosions after completion of 30 days of treatment (Rajalakshmi S. & Veluchamy G., 1996).

• The Composite Root Extract (ERE) used by the folk women of Assam consisting of (P. rosea, B. flabellifer, C. papaya (male), D. lab-lab and S. robusta) is studied for its antifiertility activity. The CRE is used by women folk during first 7 days of menstrual cycle to prevent conception. Oral ighantuyy of ethanolic extract (100 mg/kg) indicated functional aberration of the ovarian follicle (Sharma H.N. & Mohanta H.C., 2000).