Background & Aim: Chorisia is an important Bombacaceous plant that is traditionally used for a variety of ailments. Due to its richness in several bioactive phytocompounds, some Chorisia species showed a wide range of important biological effects. Accordingly, the present work was undertaken to comparatively evaluate the antioxidant potential and effects on adipogenesis of Chorisia chodatii Hassl. and Chorisia speciosa A. St.-Hil. in relation to their phenolic contents. Experimental: Total polyphenol contents and free radical scavenging potentials of the total ethanol extracts of leaves, flowers, fruits and seeds of both species, in addition to four main fractions of their leaf and flower extracts, were evaluated using the Folin-Ciocalteu's method and the DPPH assay, respectively. Besides, their effects on adipogenesis were studied using the 3T3-L1 preadipocytes model. A phytochemical screening of their different phytoconstituents was also considered. Results & Discussion: Total ethanol extracts along with their successive fractions of various parts of both species caused a concentration-dependent induction of 3T3-L1 preadipocytes differentiation, but with a noticeable reduction of the size of the lipid droplets at the lower concentrations 5 and 10 µg/ml. In addition, these extracts showed a strong evidence of their richness in free radical scavengers. The ethyl acetate, aqueous and chloroform fractions of different plant parts exhibited the greatest effects on adipogenesis, substantial free radical scavenging properties and the highest polyphenol contents, respectively. Industrial and practical recommendations: Results collectively revealed that the observed effects of both Chorisia species on adipogenesis as well as their anti-radical properties are positively related to their pool of flavonoids and other phenolics. They also suggest their potential value in obesity-related disorders and for prevention of free radical mediated diseases. Further studies for investigating the molecular basis of their effects on adipogenesis accompanied by detailed phytochemical analysis, especially of their polar and flavonoids-rich extracts, will also be strongly recommended. پرونده مقاله