Screening of antimutagenicity via antioxidant activity in different extracts from the leaves of Acacia salicina from the center of Tunisia

The effect of extracts obtained from Acacia salicina on genotoxicity and SOS response induced by Benzo(a)pyrene (B[a]P) as well as nifuroxazide was investigated in a bacterial assay system, i.e., the SOS chromotest with Escherichia coli PQ37. Preparations obtained from the leaves of A. salicina exhibited no genotoxicity either with or without the external S9 activation mixture. However, all extracts significantly decreased the genotoxicity induced by (B[a]P) and nifuroxazide. Ethyl acetate, methanol and TOF extracts exhibited the highest inhibition level of the SOS response induced by the direct mutagen nifuroxazide. Whereas, aqueous, ethyl acetate and methanol extracts displayed the greatest level of protection towards the indirect mutagen, (B[a]P), induced response. In addition to their antigenotoxic activity, TOF, aqueous, methanol and chloroform extracts showed an important free radical scavenging activity towards the 1,1-diphenyl 2-picrylhydrazyi (DPPH) free radical. These extracts showed IC50 value of 36, 73, 65, and 87 mu g/ml respectively. Taken together, our finding showed that A. salicina exhibits significant antioxidant and antigenotoxic activities. (c) 2006 Elsevier B.V. All rights reserved.