G. Nosal'Ova et al., Antitussive activity of a glucuronoxylan from Rudbeckia fulgida compared to the potency of two polysaccharide complexes from the same herb, PHARMAZIE, 55(1), 2000, pp. 65-68
An alkali-extracted low-molecular glucuronoxylan and two water-extractable
polysaccharide complexes isolated from various parts of Rudbeckia fulgida w
ere tested for antitussive activity on mechanically induced cough in nonana
esthetized cats. Glucuronoxylan consisted of a (1 --> 4)-linked beta-D-xylo
pyranosyl backbone with about 18% of 4-0-methyl-D-glucuronic acid attached
to 0-2 of the chain xylose residues. The polysaccharide complexes differed
from each the other regarding the in qualitative and quantitative compositi
on of the sugar components. It was found that peroral administration of all
the compounds led to a significant suppression of the cough reflex without
negative influence on expectoration, Glucuronoxylan and the complex from t
he aerial parts of the herb exhibited much higher antitussive activity than
the complex from the roots which did not contain any uronic acid component
. Their activity (48.2% and 46,5%, respectively) highly surpassed the activ
ity of the complex from the roots (23.5%) as well as that of the peripheral
ly acting drugs dropropizine (28.3%) and prenoxdiazine (24.7%).