Immunostimulant plant extractives as well asits isolates constitute an alternative
to conventional chemotherapy and prophylaxis of infections. In the present study
eight plants (Ecballium elaterium, Luffa cylindrica, Cucurbita maxima, Agaricus
bisporous, Pleurotus ostreatus, Oryza sativa (Rica bran), Tropaeolum majus and
Echinacea purpurea) were primarily screened for specific and nonspecific immune
responses. T. majus and E. elaterium were the most active, in addition to the well
known immunostimulant E. purpurea. Tumor Necrosis factor–alfa (TNF-) and
gamma Interferon (INF-) production were used as a measure of immunostimulatory
activity.
"Cucurbitacin D" and "2-0--D-glucopyransoyl cucurbitacin I" of E.elaterium in
addition to "5,3'-dihydroxy-7,4'-dimethoxy flavone" and 5,3'-dihydroxy-7,4'
dimethoxy flavone – 5-0– glucoside of T. majus were found to significantly stimulate
the production of both TNF-and INF-, while , "Androstan" and "4-acetyl-3,5-bis-(methyl thio)-2-pyrrolin-5-Ol" of T. majus stimulated the production of INF-only.