Characterization of Polyphenol-Containing Polar Extracts from Bassia Arabica and Nepeta Curviflora Boiss and Evaluation of their Bioactivity
عودة, ولاء فهمي حلمي
An-Najah National University
Around the world, medicinal plants are widely used to treat a wide range of human illnesses and diseases. Palestine's geographic position at the crossroads of Eurasia and Africa enhances the country's biodiversity in terms of fauna and flora. Despite its small size, Palestine supports over 2,700 plant species. The research aims to study the chemical composition and pharmacological effects of Bassia arabica and Nepeta curviflora, as well as their antibacterial and antioxidant activities. After the powdered plants were suspended in methanol, it was exhaustively extracted with ethyl acetate and fractionated using various chromatographic techniques. Ethyl acetate extracts of both B. arabica and N. curviflora were subjected to a sequence of silica gel column chromatography using different eluents with various polarities. The purity of the isolated fraction was conducted by thin- layer chromatography (TLC) and confirmed using high-performance liquid chromatography (HPLC). Moreover, functional groups of the pure fractions were detected using infrared spectroscopy. In addition, the radical scavenging capacity of plant extracts was assessed by DPPH assay, and antibacterial activity of B. arabica and N. curviflora fractions was evaluated using broth micro-dilution method based on the estimation of minimum inhibitory concentration (MIC). Fraction A3 of B. arabica display antibacterial activity against all types of bacteria, with MIC values ranging from 0.195 to 6.25 mg/mL. Ethyl acetate extract of B. arabica had the best antioxidant potential (IC50= 4.91 ± 0.03µg/mL). As a result, the water extract of N. curviflora had the strongest antioxidant capacity (IC50= 2.83± 0.25µg/mL).