This work explores underutilized peels and juice lemon (Citrus limon v. Eureka) extracts for their phenolic contents and in vitro antimicrobial activities. In this study, phenolics and flavonoids contents were found to be more present in the peel extract (30.10 ±2.98 mg of GAE/g) and (19.78±0.10 mg of QE/g) respectively compared to the juice extract (2.78 ±0.06 mg of GAE/g) and (0.13±0.001 mg of QE/g) respectively. Phytochemical study showed the presence of quercetin and gallic acid in both extracts as vanillin was identified only in the juice extract. The antimicrobial activity of peels and juice extracts was tested against six pathogen bacteria and one fungal strains using disk diffusion method. Results of this research indicated that peel extract presented an important activity on all tested strains, that gram-positive bacteria were more susceptible than gram-negative bacteria. The most susceptible gram-positive bacteria was Staphylococcus epidermedis with 32mm diameter of inhibition zone. Exceptionally Staphylococcus epidermedis that showed a higher zone of inhibition against juice extract (32mm) compared with its inhibition zone against peels extract (31mm). So, the peel extract had an inhibitory effect more than juice extract. It could be concluded that peels extract of this plant can be explored as an economically viable source of naturel antimicrobials which can be used as an alternative for antibiotics.
