Prec. Indian Aead. Sei., Vol. 88 B, Part 2, Number 1, January 1979, pp. 35-48, printed in India Pharmacognostic studies on Dillenia indica Linn. I. Leaf*. USHA SHOME, R K KHANNA and H P SHARMA Pharmacognosy Laboratory, National Botanical Research Institute, Lucknow 226 001 MS received 7 January 1978; revised 23 October 1978 Abstract. Dillenia indica Linn. is widely used in the indigenous systems of medicine; the leaf and bark as an astringent, the bruised bark, externally as a cataplasm in arthritis, and the fruit juice as a cough mixture, a cooling beverage as also for toning up the nervous system. It is considered a 'vat' suppressant ' pitta ' augmenting drug in Ayurveda. The paper deals with pharmacognosy of the leaf of D. indica. The characters studied in detail include both macroscopic and microscopic characters; physical and other constants, such as stomatal index, palisade ratio, vein islet numbers, vein termination numbers, ash values, percentages oftannins, totalsugars and reducing sugars. Preliminary phytochemical tests, TLC and fluorescence tests have also been carded out. Keywords. Dillenia indica ; pharmacognosy; Dilleniaccae. 1. Introduction Dillenia indica Linn. known as Chilta and Girnar in Hindi, Chalta in Bengali, Bhavya in Sanskrit and Elephant apple in English (Benthall 1946), belongs to the family Dilleniaceae. Nine species of the genus are reported from the Indian subcontinent (Hooker 1872). D. indica grows in tropical forests in the western peninsula, Bihar and the Himalayas from Nepal to Assam and from Sylhet to Sri Lanka (Hooker 1872). It is an evergreen tree, 9-25 m in height and up to 1.8 m in girth, with a dense rounded crown (Anon 1952). The tree is grown in gardens for its handsome foliage and attractive flowers. It is the showiest of the whole family, being equally attractive in foliage, flower and fruit (Blatter and Millard 1954). The leaves, bark and fruits of the plant are used in the indigenous systems of medicine. The leaf and the bark are used as astringents and the bruised bark is applied as a cataplasm in arthritis. The fruit juice is employed in cough mixture (Nadkarni 1954; Sharma 1956) and mixed with sugar and water, it is prescribed as a cooling beverage in fevers. It regulates the heat of the body, tones up the nervous system, removes fatigue and stops abdominal pain (Blatter and Millard 1954). The fruit is slightly laxative and acid but it is apt to induce diarrhoea when consumed too freely (Nadkarni 1954; Kirtikar and Basu 1933). It is considered as a ' rata' suppressent and a ' pitta ' augmenter in the Ayurvedic system. Green leaves are used as feed for tusser silk-worms (Ghose 1914; Badhwar et al 1944). The bruised bark is used in tanning. The wood is employed in making tool *N B R I Research Publication No. 23 (N.S.) 35 36 Usha Shome, R K Khanna and H P Sharma handles and gun stocks and is also used in construction work. It also makes good fire-wood and charcoal (Blatter and Millard 1954). The alcoholic extract of the leaves of D. indiea has been reported to possess CNS depressant activity in mice (Bhakuni et al 1969). The pharmacognostic characters of bark of D. indiea were studied by Chaudhury (1968). An abstract on its pharmacology was published by Datta (1960). However no detailed pharmacognostic work on leaf and fruit has been reported so far. The present paper deals with the morphological, anatomical quantitative, chemical and fluorescence analyses of the leaf of D. indica. The work on fruit characters is in progress and will be published subsequently. 2. Materials and methods The present studies are based on fresh and preserved material collected from the National Botanical Research Institute and the Lucknow University Gardens during the months of April and June. Form -acetic-alcohol was used as preservative and the material was subsequently stored in 70 % alcohol. However, dried material was employed for chemical and fluorescence studies. Hand and microtome sections were cut and stained in safranin as well as in safranin-fast green combinations. Ferric chloride and iodine were used for testing tannins and starch respectively. For quantitative histological examination, leaves of the same size were taken and portions from apex, middle and base were cleared in dilute nitric acid followed by chloral hydrate and mounted in glycerine. 3. General characters of the leaf The exstipulate leaves are borne alternately on the branches but assume a whorled appearance in the apical region (figure la). They are simple and broad with conspicu- ous lateral veins and vary from 14-37 em in length and 5.5-10 em in breadth. The leaves are oblong to laneeolate, pubescent, with serrate margins, asymmetric base and acuminate apex (figure la). The venation is reticulate and unieostate (figure lb; figures 2 and 3). The petioles are channelled, 2.2-4.8 em long and have sheathing bases. 4. Epidermal characters 4.1 Epidermis Cells of the lower epidermis are slightly thinner than those of the upper one (figures 4 and 5). The lower epidermal cells in young leaves are much less wavy than those in the older leaves (figures 6 and 7). Epidermal cells on both the surfaces are notably modified over the veins, leaf margins, and triohome bases. They are narrow and elongated over the veins and smaller, squarish, thick-walled and easily distinguishable from the surrounding epidermal cells at trichome bases. The cells surrounding the stomata are less wavy. Pharmacognosy studies on D. indiea leaf 37 Figure la. Dillenia indica Linn. A twig with flower bud x 43. b. Portion of a leaf showing venation. Pharmacognosy studies on D. indica leaf 39 3' .J mm ~,s. ,o-s5 ' |~ ' 9 m. 14 6 o.. 9 10 7 Figures 2-14. 2. A magnified portion of the leaf showing vein islets and vein termina- tions. 3. Leaf margin magnified to show the venation along marginal serrations. 4. Upper epidermal cells from a mature leaf. 5. Lower epidermis of a mature leaf showing thinner cell walls and stomata; one pair of stomata are arranged end to end. 6. Lower epidermis of a young leaf. 7. Lower epidermis of a mature leaf showing sinuous cell walls. 8. Trichome from the margin of the upper epidermis. 9. Tri- chome on the midrib of the lower epidermis. 10. A sepate trichome. 11. Upper epidermis showing stomata and surrounding cells at the marginal serration. 12. Portion of lower epidermis showing one pair of stomata arranged side by side. 13. Lower epidermis showing striations. 14. Epidermal cells over the lateral vein showing longitudinal striations. Proc. B.--3 40 Usha Shome, R K Khanna and H P Sharma 4.2 Trichomes Unicellular trichomes of varying size occur sparsely throughout the upper surface and along the margins but are eontined to midrib, lateral veins and veinlets on the lower surface of the leaf. The young leaves are densely covered with brown to white trichomes. Their intensity, however, decreases with the age of the leaves. The triehome walls are greatly thickened at the base (figures 8 and 9). It appears that the thickening is laid down in the form of columns on the trichome wall leaving un- thickened areas in between. As a consequence the lumen is greatly reduced. Occa- sionally, bieeUular triehomes are also found (figure 10). 4.3. Stomata The stomata in D. indica are present only on the lower epidermis except at the tip of the marginal serrations, where these occur on the upper surface. Elsewhere stomata are absent on this surface. They are slightly sunken and surrounded by thick-walled cells arranged somewhat in a circular pattern (figure 11). The stomata are typically ranunealazeous type i.e. anomocytie (figure 7). Occasionally, twin stomata are found united end to end or side to side (figures 5 and 12). 4.4. Cuticle The cuticle of the lower epidermis has striations radiating from the stomata occurring near the lateral veins, as also reported in Hibbertia dentata (Dickison 1970). Longi- tudinal striations are also present on epidermal cells over the lateral veins (figures 13 and 14). Elsewhere the striations are less prominent and at places they can be made out only with difficulty. 5. Anatomy of the leaf 5.1. Petiole The petiole is densely covered with triehomes on its abaxial side. It has a broad and flat adaxial groove (figures 15-17). The petiolar bundles are arranged in the form era crescent in its lower region (figure 15). Further up the vascular bundles come nearer, coalesce and become enclosed in a common sclerenchymatous perieycle with marginal traces in the wings (figures 16 and 17). The epidermis on both sides is highly eutieularised and consists of small rectangular cells (figure 18). The cortex can be differentiated into an outer zone of small thick walled collenehymatous cells and an inner zone formed of large parenehymatous isodiametrie cells having intercellular spaces in between (figure 18). No well-defined endodermis could be differentiated. The pericycle consists of two or three layers of selerenehymatous fibres (figures 18, 28-35). The phloem is composed of sieve cells, sieve tubes and phloem parenchyma (figures 18 and 48). The xylem is composed of spiral, annular, scalariform perforated and pitted vessels, tracheids, xylem fibres and xylem parenchyma (figures 36-47). Large parenchymatous ceils constitute the pith. Pharmacognosy studies on 1). indica leaf 41 19 9 1ram ir-m 9 16 \ ,. - /:" PH 18 SCHII 15 -,...a Figures 15-20. 15-18. Transverse sections of a petiole (diagrammatic). 15. Basal region showing free vascular bundles. 16. Middle region showing the vascular bundles arranged close to one another. 17. Upper region--The vascular traces of basal veins are separated; the stelar bundles are reorganising.