It is an evergreen dioic woody vine, 2 - 4 m high with lignified rhizomes. Rhizome is voluminous, with tuberous swelling, reddish brown in color, measuring 14 - 21 cm long, 3.925 cm wide and 3.175 cm high. The average weight is around 87.05 g. Roots are adventitious, growing from the rhizomes (Figure 1).

The powder drug is reddish brown in color, and displays a characteristic flavor and smell (Figure 2).

In this paper, the description by Huft [2] is enriched by our botanical observations. It is evident that the analyzed spice has a great coincidence by the description done by Ferrufino & Gómez-Laurito [11] , and Cáceres [12] . We finally arrived to a clear description of S. domingensis in Cuba, represented by a big woody red rhizome.

Analyzed individually, Fragmented drug shows the anatomical features in Figure 3. Cortical parenchyma cells are elongated, with idioblasts containing calcium-oxalate raphides, mucilage, and granular material (3A); long phloems

measuring 36 µm wide, with appendage and simple terminal plate (3B) and scalariformly thickening vessels (3C and 3D).

This is the first time that the micromorphological characteristics of S. domingensis rhizome are described, as well as the powder drug in our country.

Preliminary phytochemical screening suggested the presence of flavonoids, alkaloids, coumarins, catechins, pyrochatecolic tannins, fat and/or volatile oils, saponins, triterpens and/or steroid, quinones and reducing sugars, and the absence of resins, amino acids or amines, cardiotonic glycosides, anthocyanidins and astringents and/or bitter principles (Table 1). Data presented here refer to evaluations with wild material. Further studies are needed to establish the molecules responsible for the real chemical composition.

There were three absorption peaks at 205 nm, 280 nm and 394 nm. There may be the presence of flavonoids in 70% ethanol extract [13] . This result corroborates the suggested presence of flavonoids after phytochemical screening (Figure 4).

TLCP (thin-layer chromatography plate) presented four obvious spots (Figure 5). Under ordinary light two spots were observed, the first one (1) with R_f = 0.37 and the second one with R_f = 0.83. Both spots are cream-yellowish in

Legend: + (positive); ++ (very positive); +++ (highly positive); − (negative).

color (5A). The colorimetric detection with concentrated sulfuric acid and heat presented the same two spots, with the identical R_f (0.37; 0.83), but, with different colors, the first one yellow-green and the second one yellow-orange, both of them representative of chemical compounds type flavonoids [14] [15] and another one appear near the solvent front red violet in color that could be related with terpenoids structures (5B). Colorimetric detection with FeCl₃ showed two spots (4) with R_f = 0.78 and another one near the solvent front (R_f = 0.90), both of them black green in color, indicating the presence of phenolic compounds derivates from catechol (5C). In colorimetric detection with AlCl₃ were observed two spots (3 R_f = 0.52; another one R_f = 0.90), both spots with few chromatography complexity at ordinary light (5D), but changing their colors under UV 365 nm to pale yellow (3) and the other one to more brilliant yellow, and inside this last one and near to the solvent front, another one clear blue (R_f = 0.94) (5E). Under UV 254 nm, the spots change in tonality, the three firsts with reddish orange colors, typically from chemical compounds like flavonoids and another one in the solvent front clear blue intense (5F).

The chemistry of Smilax has been described primarily for the long roots and small rhizome type of species, which include steroidal saponins, flavonoids, polyphenols and stigmasterol [5] .

Phytochemical screening of the extract by macro, semi-micro and TLC demonstrated steroids by Salkowsky, Liebermann-Burchard and foam test; flavonoids and anthocyanins by Shinoda and TLC (Rf 0.24 - 0.89). Alkaloids, antraquinones and tannins were not detected, only phenolic compounds by FeCl₃. Ethanol (50%) extracts and fractions showed flavonoids, saponins, sesquiterpene lactones, coumarins and tannins. Rhizomes from female and male plants showed little difference, particularly the presence of sesquiterpene lactones in female plants, and the lack of these in male rhizomes. Flavonoids were present in the 1:1 extract at 0.02% ± 0.01% and in the dry extract at 0.08% ± 0.01%, expressed as quercetin; steroidal sapogenins in the 1:1 extract were 0.68% ± 0.02%, and in the dry extract 1.63% ± 0.02%. Contrary to expected according to the literature, sarsapogenin, smilagenin or steroids (stigmasterol, β-sitosterol and cholesterol) were not detected by GC/MS analysis, according to the molecular masses of known saponins from Smilax officinalis. From 10 samples from different locations in Guatemala, chromatographic profiles were similar, with the exception of a sample from Carchá, which showed fragmentation patterns similar to sarsapogenin/smilagenin, which correspond to Smilax kunthii [12] .

Moisture content (13.11%) was inside the limited index (8% - 14%). Extractable matter in ethanol at 70% (13.53%) suggests that this solvent is appropriated to the extraction of active components from the rhizomes. Total ash (3.45%) is according to the standard allowed (3% - 5%), while water soluble ash (2.43%) was relatively higher than the standard for medicinal plants (< 2%), the possible reason is that medicinal rhizome is not clean, containing soil and another inorganic impurity. Acid insoluble ash (0.64%) was lower than the standard (< 2%).