Salacia
reticulata has a pale yellow bark. Leaves are simple, opposite,
ovate or obovate-oblong, coriaceous, shortly acuminate, glabrous and
shining. Flowers are yellowish green in color and fascicled on woody
axillary tubercles. Fruits are large, tuberculate, and bright pinkish
orange. Each fruit contains 1-4 seeds immersed in the pulp.
Anthocyanidins,
catechins, phenolic acids, quinones, friedo-oleananes, triterpene
quinone-methides, and related triterpenoids (celastroloids), mangiferin,
gutta-percha, and dulcitol have been isolated from plants of the Salacia
species. Phytochemical studies conducted on Salacia
reticulata lead to the isolation of gutta-percha, sitosterol
pristimerin, mangiferin, three catechins (-)-epicatechin,
(-)-epigallocatechin, and (-)-4’-O-methylepigallocatechin),
two catechin dimers, epi-kokoondiol, salacenonal,
salaciquinone, and two novel quinonemethide triterpenoids
(celastroloids), isoiguesterinol and 30-hydroxypristimerin,
from the root bark and iguesterin, pristimerin and epi-kokoondiol
from the stem bark. Salacinol and kotalanol have been
identified from both the roots and stems of S. reticulata.
Mangiferin
(a xanthone from the roots) and sulfonium ion derivatives, kotalanol
(from the roots and stems) and salacinol (from the roots and stems),
have been identified as the antidiabetic principles of S. reticulata
through pharmacological studies. Mangiferin, salacinol and kotalanol
are potent a-glucosidase inhibitors that have been shown to inhibit
increases in serum glucose levels. Mangiferin also inhibits aldose
reductase activity, thereby delaying the onset or progression of diabetic
complications (e.g. diabetic neuropathy and nephropathy). The polyphenol
constituents of
S. reticulata, the catechins, also contribute to the antidiabetic
property of the plant.
