Polysaccharides have various effects and exhibit several bioactivities that possess an enormous influence on healthcare due to their therapeutic beneficial and comparatively low toxicity. The study is focusing in investigation of the chemical structure of the isolated polysaccharides from wastes of Punica granatum, Musa acuminate, and Brassica oleracea, beside to validation of the analgesic, anti-inflammatory, antipyretic and antiulcer activities. Moreover, the polysaccharide yields were determined, characterization of the hydrolyzates was performed using UV-visible, FT-IR, 1HNMR and GLC analyses. In addition, significant biological activities were obviously presented by all the isolated polysaccharides. The highest analgesic and anti-inflammatory activities exhibited by polysaccharides of B. oleracea outer leaves (62.98 and 81.69 %), followed by that of P. granatum peels (53.31 and 78.17%), and that of M. acuminate peels (50.50 and 76.05%), while the antipyretic activity was showed nearly the same results for both M. acuminate and B. oleracea polysaccharides (6.59 and 6.35%), then that of P. granatum peels (5.30%). On the other, the antiulcer activities of polysaccharides of different wastes showed corrective action of inflammatory markers including tumor necrosis factor -α (TNF-α), interleukin -6, 8 (IL-6 &8), myeloperoxidase (MPO) as well as lowering oxidative stress, improved lesion count which lead to ameliorations in histopathological picture of stomach. In conclusion, the polysaccharide isolated from Musa acuminate showed the most potent therapeutic effect in the majority of the biomarkers under investigation.