Abstract
Opuntia Ficus Indica(OFI) is widely cultivated in arid and semiarid areas of Tunisia and other parts of the world and reported to have sound biological activities. The current work aimed at investigating the effect of various solvent concentrations (80% acetone, 80% methanol and 80% ethanol) on extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity using three assays: DPPH, ABTS and FRAP and antibacterial activity of Red and yellow-orange (YO)OFIskin and pulp extracts. Results showed high content of polyphenols and flavonoids ranging from 3.046 to 86.287 mu g GAE/mg DW and from 0.167 to 11.917 mu g QE/mg DW respectively. Although pulp extracts had the highest extraction yield, skin extracts exhibited the highest TPC, TFC and antioxidant activity and in most cases the highest antibacterial activity. The 80% acetone extracts exhibited the lowest yield extraction but showed the highest TPC, TFC and the strongest antioxidant activity compared to the 80% methanol and 80% ethanol extracts except for Red pulp. Among all extracts, the 80% acetone YO skin extract showed the best TPC (86.287 mu g GAE/mg DW), TFC (11.917 mu g QE/mg DW). Moreover, it showed the highest antioxidant activity (DPPH IC50 = 0.784 mg/mL, ABTS IC50 = 0.829 mg/mL and FRAP EC50 = 1.285 mg/mL). The antibacterial activity tests showed that the 80% ethanol of YO skin extract had the most influence on the inactivation of the Gram-positiveEnterococcus feaciumbacteria type(zone of inhibition = 11.00 mm) compared to other extracts. In addition, the 80% acetone extracts showed better antibacterial activity compared to hydro-alcoholic extracts against other bacterial strains.