Antioxidant and antimicrobial activities of methanolic extract of gamma irradiated parsley (Petroselinum crispum) at dose levels of 0, 3, 6 and 9 kGy were determined, and the composition of methanolic extracts of non-irradiated and irradiated parsley were identified by GC-MS. The results showed that methanolic extracts of non- irradiated and irradiated parsley samples had a higher content of total phenolic compounds and exhibited antioxidant of DPPH radical scavenging activity. Based on these results, methanolic extract samples of irradiated parsley at 6 kGy were selected for their higher activity as antioxidant compared to other samples, owing to their high content of total phenolic compounds and scavenging effect on DPPH radical. The analysis by GC/MS led to the identification of 23 and 24 components for non-irradiated and irradiated samples at (6.0 kGy) respectively. The main compound of non-irradiated parsley methanolic extract is acetic acid ethyl ester (28.5%). Meanwhile, the main compound of irradiated parsley at 6.0 kGy methanolic extract was phenol, 2- methoxy-3 (27.3 %). The antibacterial effect of methanolic extract samples of non-irradiated and irradiated parsley and the minimum inhibitory concentration (MICs) values were assayed. The irradiated parsley (6.0 KGy) methanolic extract was generally more effective against tested bacterial strains than non-irradiated parsley extract. The study exhibited that Gram- negative bacteria under study were more sensitive than Gram- positive one .The MICs values of tested bacteria to the irradiated parsley (6.0 kGy) methanolic extract were in the range 4 to 20 µgml-1. In conclusion, it can be possible to employ the methanolic extract of parsley in the food industry and in particular that extract from parsley irradiated at 6.0 kGy as natural food additives.
Keywords: parsley / Gamma irradiation / methanolic extract / Antioxidant/ Antimicrobial
