สารบัญ

         Tarlmounia Elliptica Leaf is the dried full-grown leaf of Tarlmounia elliptica (DC.) H. Rob., S. C. Keeley, Skvaria & R. Chan (Vernonia elliptica DC., V. elaeagnifolia DC.) (Family Compositae), Herbarium Specimen Number:  DMSC 230, Crude Drug Number:  DMSc 0558

Constituents  Tarlmounia Elliptica Leaf contains glaucolides A and B and their acetates, along with lupeol, taraxasterol, sitosterol, and stigmasterol. 

Description of the plant  (Figs. 1a, 1b)  Scandent shrub; branch slender with longitudinal ridge, densely silvery hairs.  Leaves simple, alternate, ovate, obovate, elliptic or oblong, 6 to 10 cm long, 3 to 4.5 cm wide, apex acute or obtuse, base obtuse, margin entire or remotely serrate, coriaceous, upper surface glabrous, lower surface densely covered with silvery hairs; veins 7 to 9 pairs; petiole 2 to 10 mm long.  Inflorescence paniculate, corymbose heads of 3- to 5-flowered, 10 to 40 cm long, at the end of branches or on upper axil of the leaves, flower-heads numerous, purple at first, becoming whitish on fading, sweet smelling;  involucral bracts elliptic, 1 to 4 mm long, apex obtuse, shortly pubescent; calyx pappus; corolla-tube with 5-oblong toothed at the apex; stamens 5, anther sagittate at base; style divided into 2 branches.  Fruit achene, terete, about 2 mm long, about 1 mm wide, terete, compressed, longitudinally ribbed, covered with light brown translucent glands, crowned  by the pappus, 4 to 8 mm long, base pointed. 

Description   

       Macroscopical  (Fig. 1a)  Dried leaves more or less crumpled, blade ovate, obovate, elliptic or oblong from 6 to 9 cm long, and 2 to 4 cm wide, coriaceous; upper surface pale greenish brown to greyish brown, lower surface pale greyish brown and showing prominent midrib; petiole 4 to 10 mm long. 

          Microscopical  (Figs. 2a, 2b)  Transverse section of the leaf shows upper epidermis,  a single layer of cuticularized rectangular cells, with few uniseriate multicellular trichomes and multicellular glandular trichomes.  Mesophyll consisting of a single- or double-layer palisade parenchyma, some containing a small rosette aggregate crystal of calcium oxalate and several layers of irregular-shaped spongy parenchyma rich in chloroplastids. Through this region scattered small vascular bundles. Lower epidermis, a single layer of rectangular cells, with multicellular glandular trichomes and numerous T-shaped nonglandular  trichomes, each with one horizontal, tapering end cell on short, 1- to 2-celled stalk.

     Transverse section through the midrib of lamina shows several layers of collenchyma underneath the epidermis, parenchyma and collateral vascular bundles. 

      In surface view, epidermides of upper and lower surfaces are polygonal cells, with much more anomocytic stomata in the lower epidermis than in the upper one.

       Tarlmounia Elliptica Leaf in powder possesses the diagnostic microscopical characters of the unground drug.

Packaging and storage  Tarlmounia Elliptica Leaf shall be kept in well-closed containers,  protected from light, and stored in a dry place. 

Identification

       A. To 500 mg of the sample, in powder, add 2 mL of acetic anhydride, warm on a water- bath for about 2 minutes, shake, and filter.  Slowly add 1 mL of sulfuric acid to the filtrate to form a layer:  a brownish red ring forms at the zone of contact. 

       B. Carry out the test as described in the “Thin-Layer Chromatography” (Appendix 3.1), using silica gel G as the coating substance and a mixture of 70 volumes of hexane, 29 volumes of ethyl acetate and 1 volume of glacial acetic acid as the mobile phase.  Apply to the plate,   10 μL of the test solution prepared by refluxing 500 mg to 1 g of the sample, in powder, with 10 mL of methanol on a water-bath for about 20 minutes and filtering.  After removal of the plate, allow it to dry in air and spray with a 1 per cent w/v solution of diphenylboric acid β-aminoethyl ester in methanol.  Examine the plate under ultraviolet light (366 nm); five orange spots appear (Table 1); see also Fig. 3. 

Table 1 hR_f Values of Components in Methanolic Extract of the leaves of Tarlmounia elliptica (DC.) H. Rob., S. C. Keeley, Skvaria & R. Chan

Loss on drying  Not more than 11.0 per cent w/w after drying at 105° to constant weight (Appendix 4.15).

Acid-insoluble ash  Not more than 2.0 per cent w/w (Appendix 7.6).

Sulfated ash  Not more than 20.0 per cent w/w (Appendix 5.3).

Ethanol-soluble extractive  Not less than 5.0 per cent w/w (Appendix 7.12).

Water-soluble extractive  Not less than 14.0 per cent w/w (Appendix 7.12).

Chloroform-soluble extractive  Not less than 4.0 per cent w/w (Appendix 7.12H).