**Abstract**

The current work was addressed to characterize gallic acid from amla fruit and quercetin from peels of pomegranate fruit and formulated into Chitosan (CS) nanoparticles and to evaluate their cytotoxicity towards human colorectal cancer (HCT 116) cell lines. Identification of the biomolecules was performed by chromatographic and spectroscopic techniques and characterization of gallic acid and quercetin loaded chitosan nanoparticles carried out by using FT-IR, X- ray diffraction, entrapment efficiency and loading content confirmed successful encapsulation of biomolecules into nanoparticles. *In vitro* drug release studies done by using simulated fluids at various pH (1.2, 4.5, 7.5, and 7.0) to mimic the GIT tract and achieved drug releases 77.56% for gallic acid 79.06% for quercetin at 24 hr. in a sustained manner. The human HCT116 cell line by MTT assay results inferred that the synthesized CS nanoparticles demonstrated shows more effective antiproliferative potential with IC50 value of 36.17 ug/ml than polyherbal extract 60.32ug/ml.

**Keywords:** gallic acid, quercetin, chitosan nanoparticles
