Biological Properties of <i>Chamaerops Humilis</i> L.: Antioxidant and Antibacterial Activities of Leaf, Fruit and Pulp Extracts

Abstract

This work aimed to evaluate the polyphenol and flavonoid composition, antioxidant and antibacterial activity of leaf, fruit and pulp extracts of Chamaerops humilis L. Dry extracts of leaves, fruits and pulp were prepared by ultrasonic extraction and examined as potential sources of phenolic compounds and flavonoids. Different methods were used to evaluate the antioxidant activity of the extracts, including DPPH free radical scavenging assay and total antioxidant capacity (TAC). The total polyphenol content (TPC) and total flavonoid content (TFC) of the tested extracts were examined by the Folin-Ciocalteu and aluminium chloride (AlCl 3 ) methods, respectively. The antibacterial activity of leaf, fruit and pulp extracts against a collection of bacterial strains was evaluated using various in vitro methods, including well diffusion, minimum inhibitory concentration (MIC) and minimum bacte - ricidal concentration (MBC). The results suggest that the leaf, the fruit and the pulp extracts have good potential as sources of bioactive compounds, the TPC and TFC of leaves were 116.209 ± 1.58 and 2.313 ± 0.02 mg GAE/g d.w, respectively. The TPC and TFC were 78.621 ± 1.06 and 0.425± 0.02 mg GAE/g dry weight in fruits, respectively. The best ability to trap DPPH radical was observed in the leaf extract (IC50 = 4.006 ± 0.36 mg/ml d.w); also, this extract revealed a better total antioxidant capacity of 119.702 ± 1.59 mg AGE/g dry weight. Regarding antibacterial activity, the leaves showed an important antibacterial activity against the tested microorganisms with MIC ranging from 0.195 mg/ml to 3.125 mg/ml and with an inhibition diameter ranging from 12.03 ± 0.2 mm to 16.26 ± 0.03 mm Furthermore, a strong correlation was observed between phytochemical parameters (TPC and TFC) and biological activities (antioxidant and antimicrobial activities). These results revealed that leaves, fruits and pulp extracts of C. humilis are a good source of bioactive compounds with potent antioxidant and antibacterial potentials. Therefore, they can be a new and alternative source of products for medical and industrial applications.