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      Drumstick-tree Leaf is the dried leaflets of Moringa oleifera Lam. (M. pterygosperma Gaertn.) (Family Moringaceae), Herbarium Specimen Number: DMSC 5262, Crude Drug Number: DMSc 0945.

Constituents Drumstick-tree Leaf contains flavonoids and their glycosides (e.g., astragalin, kaempferol, quercetin) and phenolic acids (e.g., gallic acid). It also contains nitrile, carbamate and isothiocarbamate glycosides, carbohydrates, proteins, minerals, etc.

Description of the plant (Fig. 1) Tree up to 12 m tall; bark smooth or finely rugose, pale grey or brownish, lenticellate. Leaves 2 to 4 imparipinnate, spirally arranged, 20 to 70 cm long; rachis articulate, with conspicuously small linear or clavate stalked glands at base of rachis and rachilla; petiole 7 to 15 cm long, pulvinate at base; leaflets ovate, obovate, or oblong, 0.5 to 3 cm long, 0.3 to 2 cm wide, apex round to subemarginate, whitish mucronulate, base round to cuneate, margin entire, membranaceous, puberulous when young, glabrous when mature; petiolule slender, 1 to 2 mm long, with stalked glands at base. Inflorescence paniculate, terminal and axillary, widely spreading, 10 to 30 cm long; bract and bracteole linear, about 1 mm long. Flower creamy white; hypanthium green; sepals 5, about 1.5 cm long, connate at base, proximal ones usually reflexed, puberulous, distal most pair usually largest, more or less erect, enclosing banner petal, or more or less reflexed; petals 5, lanceolate, 1 to 2 cm long, 5 to 8 mm wide, distal most banner petal more or less erect, others usually reflexed, puberulous, short stalk at base, apex acute; fertile stamens 5, staminodes 5, filament 0.7 to 1 cm long, basally pubescent, anther yellow, oblong, basifixed; ovary superior, 1-loculed, ovules numerous, style slender, 3 to 5 mm long, stigma minute. Fruit dehiscent, pendulous capsule, dagger-shaped, 18 to 70 cm long, 1 to 3 cm wide, acuminate, 3- or rarely 4-angled, subconstricted. Seed broadly elliptic or subglobose, 0.6 to 1 cm long, 0.5 to 1 cm wide, pale brown to dark brown; 3-winged, 2 to 4 cm long, 0.4 to 1 cm wide.

Description Odour, characteristic; taste, slightly bitter.
Macroscopic (Fig. 1) Drumstick-tree Leaf occurs as a mixture of entire and broken, green to brownish green leaflets, without petioles and rachis of the compound leaf. Complete leaflets, green to dark green on upper surface, greyish green or yellowish green on lower surface, ovate, obovate, or oblong, apex round to subemarginate, whitish mucronulate, base round to cuneate, margin entire, more or less glabrous.
Microscopical (Figs. 2a, 2b, 2c) Transverse sections of the leaflet through midrib and lamina show upper epidermis, mesophyll, vascular bundle, and lower epidermis. Upper epidermis: a layer of rectangular cells, sunken stomata, idioblasts, and unicellular trichomes.
Mesophyll: palisade cells, 1 to 3 layers, cylindrical, some containing oil droplet; spongy cells, irregularly shaped, loosely arranged, some containing oil droplets and rosette aggregates or prismatic crystals; collenchyma, angular, occurring in the lower part of midrib, some containing rosette aggregates. Vascular bundle: xylem in the upper part and phloem in the lower part. Lower epidermis: a layer of small rectangular cells, sunken stomata and unicellular trichomes.

In surface view, upper and lower epidermises of the lamina show slightly wavy-walled cells, unicellular trichomes and sunken stomata.
Drumstick-tree Leaf in powder possesses the diagnostic microscopical characters of the unground drug. Sunken stomata in both upper and lower epidermises, palisade cells containing oil droplets and idioblasts are characteristic.

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

Identification
       A. Reflux 500 mg of the sample, in coarse powder, with 20 mL of water for 20 minutes and filter. To 1 mL of the filtrate, add a few drops of iron(III) chloride TS and mix: a black-blue colour develops.
       B. Reflux 500 mg of the sample, in coarse powder, with 10 mL of absolute ethanol for 20 minutes and filter. To 1 mL of the filtrate, add 0.5 mL of a 0.2 per cent w/v solution of ninhydrin and warm on a water-bath for 2 minutes: a violet colour develops.
       C. Carry out the test as described in the “Thin-Layer Chromatography” (Appendix 3.1), using a high-performance plate with silica gel F254 as the coating substance and a mixture of 80 volumes of ethyl acetate, 4 volumes of glacial acetic acid, 4 volumes of formic acid, and 8 volumes of water as the mobile phase and allowing the solvent front to ascend 8 cm above the line of application. Apply separately to the plate as bands of 10 mm, 4 μL of solution (A) and 2 μL of solution (B). Prepare solution (A) by refluxing 500 mg of the sample, in coarse powder, with 20 mL of absolute ethanol for 20 minutes, filtering and evaporating the filtrate under reduced pressure to dryness. Dissolve the residue in 4 mL of absolute ethanol. For solution (B), dissolve 1 mg of astragalin in 1 mL of absolute ethanol. After removal of the plate, allow it to dry in air and examine under ultraviolet light (254 nm), marking the quenching bands. The chromatogram obtained from solution (A) shows a quenching band (hRf value 55 to 57) corresponding to the astragalin band from solution (B) and several other quenching bands are also observed. Heat the plate at 80° for 10 minutes and then spray with natural products (NP) TS while the plate is still warm. Subsequently spray the plate with polyethyleneglycol (PEG) TS and observe the colours of the bands under ultraviolet light (366 nm) through the cut-off filter within 5 to 15 minutes; the band due to astragalin is green fluorescence and several other fluorescent bands of different colours are also observed (Table 1); see also Fig. 3.

Table 1 hR_f Values of Components in Ethanolic Extract of the Leaflets of Moringa oleifera Lam.

       *astragalin

Loss on drying Not more than 10.0 per cent w/w after drying 5 g at 105° for 5 hours (Appendix 4.15).

Foreign matter Not more than 2.0 per cent w/w (Appendix 7.2).

Acid-insoluble ash Not more than 0.5 per cent w/w (Appendix 7.6).

Total ash Not more than 13.0 per cent w/w (Appendix 7.7).

Ethanol-soluble extractive Not less than 13.0 per cent w/w (Appendix 7.12).

Water-soluble extractive Not less than 30.0 per cent w/w (Appendix 7.12).