Evaluation of Crude Plant Extracts for their Total Phenolic Content, Antioxidant Activity, and Other Phytochemicals with Potential Applications in Health

  • Saeed A. Alkhoori

Student thesis: Master's Thesis


Due to extreme heat, water scarcity, and saline soil, UAE's floral kingdom developed unique survival traits by producing distinctive active phytochemicals. This study evaluates the Total Phenolic content (TPC), DPPH radical scavenging activity and spectral profile of botanical extracts from four native plant species that belongs to genera: Arthrocnemum, Tetraena, Calotropis, and Tamarix. Biomass were extracted using Soxhlet Extraction with different absolute ethanol concentrations v/v (25%, 50%, and 75%). Arthrocnemum sp. and Tamarix sp. extracts exhibited higher DPPH scavenging activity when assayed at a low concentration of 0.03 mg/mL compared to the other two botanical extracts which had substantially lower DPPH scavenging activity when assayed at this same concentration. TPC increased with increasing concentration of ethanol in the extraction solvent for all plants except Calotropis sp.. Highest TPC was found in Tamarix sp. when extracted with 50% ethanol (~178 mg.GAE/g.dry weight), and the lowest TPC was found in Tetraena sp. when extracted with 25% Ethanol (~22 mg.GAE/g.dry weight). Infrared and visible spectral analysis of the botanical extracts suggest differences in chemical composition. Preliminary chemical characterization of the extracts also suggests the presence of alkaloids, saponins and other medicinally valuable compounds.
Date of AwardMay 2017
Original languageAmerican English
SupervisorLina Yousef (Supervisor)


  • Plant Extracts
  • Total Phenolic Content
  • Botanic Extracts Phenolics
  • Phytochemicals
  • Antioxidants.

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