Antibacterial and antioxidant activity of peach leaf extract prepared by air and microwave drying

Abstract

In this study, antioxidant and antimicrobial effects of methanol and water extracts of peach leaves dried in air and microwave drying on E. coli ATCC 25922 and L. monocytogenes ATCC 7644 were investigated. Pathogens were inoculated into broth medium prior to the extract addition. Samples were then kept at 4°C for 15 min. The highest inhibitory effect on the samples inoculated with E. coli at 5.44 ± 0.03 cfu/ml and 7.44 ± 0.03 cfu/ml levels was obtained from the treatment of microwave-water; the final enumeration counts of E. coli were 3.80 ± 0.01 cfu/ml and 5.44 ± 0.07 cfu/ml, respectively. Similarly, the highest inhibitory effect on the samples inoculated with L. monocytogenes at 5.18 ± 0.02 cfu/ml and 7.18 ± 0.02 cfu/ml levels was obtained from the treatment of microwave-methanol; the final enumeration counts of L. monocytogenes were 4.40 ± 0.03 cfu/ml and 6.03 ± 0.07 cfu/ml, respectively. Inhibitory activity of microwave-dried peach leaf extracts was higher. The highest TPC (4.08 mg GAE/ml) values were obtained from air-dried samples extracted by water. The DPPH value of both extracts of microwave-dried samples was higher than the air-dried samples. The results indicate methanol extracts as an antimicrobial and antioxidant agent may be used to reduce microbial population. Novelty Impact Statement The highest Total phenolic content (4.08 mg GAE/g) values was seen samples that dried in the air extracted with water. All samples TEAC values changed from 0.86 to 5.35 mg TEAC/g. The Inhibitory effect of all peach leaf extracts on E. coli and L.monocytogenes was found statically important (p < .05).