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          Piper Sarmentosum Leaf is the dried leaf of Piper sarmentosum Roxb. (Family Piperaceae), Herbarium Specimen Number:  DMSC 2714, BKF 160077, Crude Drug Number:  DMSc 0686.

Constituents  Piper Sarmentosum Leaf contains phenylpropanoids.

Description of the plant  (Figs. 1a, 1b)  Herb erect or creeping, often stoloniferous, swollen node.  Leaves simple, alternate, stipulate; suborbicular ovate, or ovate-oblong, 7 to 15 cm long, 5 to 10 cm wide, surface glabrous or short hairs, apex acute to shortly acuminate, base cordate to obliquely obtuse or rounded, margin entire, slightly undulate, veins palmately 5- to 7-nerved, prominent on lower surface; petiole 2 to 5 cm long.  Inflorescence  leaf-opposed dense spike, generally unisexual.  Male spike white, 1.5 to 3 cm long; peduncle 0.5 to 1.5 cm long; stamens 2 to 3, filament very short, anther subglobose.  Female spike whitish, 2 to 5 cm long; peduncle 0.5 to 1.5 cm long; stigmas 3 to 4.  Fruit drupe, obovoid, dark green when ripe.  Seeds small. 

Description  Odour, characteristic; taste, slightly pungent.

          Macroscopical  (Fig. 1a)  A mixture of entire and broken leaves.  Entire leaf, ovate or obovate-oblong, 3.5 to 13 cm long, 2.5 to 7 cm wide; apex, acuminate; base, cordate or obtuse or obliquely obtuse; upper surface green to greenish brown, lower surface green to greyish green, lighter colour; petiole brown, 1 to 6 cm long.

          Microscopical  (Figs. 2a, 2b, 2c)  Transverse section of the leaf shows upper epidermis,  a single layer of cuticularized rectangular cells, polygonal in surface view, with few unicellular trichomes and pearl glands.  Mesophyll, a single layer of palisade parenchyma and several layers of round spongy parenchyma with scattered small vascular bundles.  Lower epidermis, a single layer of rectangular cells, polygonal and irregular shape in surface view; stomata, mostly anomocytic.  Hypodermis, 1 to 2 layers of cells under upper and lower epidermises of midrib and nearby area, and leaf margin.

          Transverse section through the midrib of lamina shows several layers of collenchyma underneath the epidermis, parenchyma and collateral vascular bundles.  Trichomes, 1 to 3 cells, uniseriate nonglandular, abundant at lower epidermis.

          Piper Sarmentosum Leaf in powder possesses the diagnostic microscopical characters of the unground drug.

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

Identification

          A. Macerate 500 mg of the sample, in coarse powder, with 25 mL of ethanol for 24 hours,  filter, and evaporate the filtrate to dryness.  Dissolve the residue in 10 mL of dilute sulfuric acid and filter (solution 1).  To 2 mL of solution 1, add a few drops of mercuric-potassium iodide TS:  a white precipitate is produced.

          B.To 2 mL of solution 1, add a few drops of modified Dragendorff TS1:  an orange precipitate is produced.

          C. Boil 500 mg of the sample, in coarse powder, with 10 mL of water in a water-bath for 10 minutes and filter.  To 2 mL of the filtrate, add 1 or 2 drops of a 1 per cent w/v solution of iron(III) chloride:  a greenish grey precipitate develops.

          D. Carry out the test as described in the “Thin-Layer Chromatography” (Appendix 3.1), using silica gel GF254 as the coating substance and a mixture of 3 volumes of ethyl acetate and 1 volume of toluene as the mobile phase.  Apply to the plate, 10 µL of the test solution  prepared by macerating 500 mg of the sample, in coarse powder, with 25 mL of ethanol for 24 hours, filtering, and evaporating the filtrate to dryness.  Dissolve the residue in 1 mL of ethanol.  After removal of the plate, allow it to dry in air and examine under ultraviolet light (254 nm), marking the quenching spots.  Subsequently examine the plate under ultraviolet light (366 nm) through the cut-off filter; several fluorescent spots of different colours are  observed.  Spray the plate with modified Dragendorff TS1; several spots of different colours appear (Table 1); see also Fig. 3.

Loss on drying  Not more than 10.0 per cent w/w after drying at 105° to cons tant weight (Appendix 4.15).

Acid-insoluble ash  Not more than 7.0 per cent w/w (Appendix 7.6).

Total ash  Not more than 20.0 per cent w/w (Appendix 7.7).

Ethanol-soluble extractive  Not less than 7.0 per cent w/w (Appendix 7.12).

Water-soluble extractive  Not less than 20.0 per cent w/w (Appendix 7.12).