Antiproliferative and Antimicrobial Activities of <i>Citrus limon</i> (L.) Burm. f. Stem Bark Extract

Abstract

Citrus limon is traditionally use for the treatment of several ailments including infectious diseases. This study was designed to evaluate antiproliferative and antimicrobial activities of Citrus limon stem bark extract. The plant material was collected, authenticated, air-dried and pulverized. Two hundred grams of powdered plant material was extracted into distilled methanol by cold maceration and the extract was concentration in a vacuo. The extract was subjected to in vitro phytochemical screening and bioassays including; antiproliferative assay (Sorghum bicolor radicle and Allium cepa root growth inhibitory assays) and antimicrobial susceptibility against Escherichia coli, Staphylococcus aureus, Citrobacter ferundii and Candida albicans. Phytochemical evaluation detected the presence of alkaloids, flavonoids and cardiac glycoside in the extract. The extract displayed concentration-dependent antiproliferative activity with an IC₅₀ of 1.10±0.07 and 0.62±0.04 mg/mL compared to cyclophosphamide (IC₅₀ of 0.17±0.02 and 0.83±0.08 mg/mL) for Sorghum bicolor radical growth and Allium cepa root growth inhibitory assays, respectively. The extract displayed antimicrobial activity with the highest activity against Escherichia coli and Citrobacter ferundii with activity indices of 0.68 and 0.59, respectively compared to gentamicin. Citrus limon stem bark extract displayed antiproliferative and antimicrobial activities.