PHYTOCHEMICAL CONSTITUENTS AND PPAR α/γ AGONIST ACTIVITY OF JUNIPERUS COMMUNIS BERRIES AND COMPARISON STUDIES OF J. COMMUNIS BERRIES TO SAUDI JUNIPERUS SPECIES (ARAR): J. PROCERA AND J. PHOENICEA

Abstract

Juniperus communis is distributed over a large geographical area mainly in the Northern Hemisphere across multiple continents making it the most known and medically used species among 75 other Juniperus species. One of the main traditional uses of J. communis that has been proven by several studies is its antidiabetic properties. An ethanolic extract of J. communis berries has shown promising antidiabetic results leading us to investigate its phytochemical constituents and to identify the active compounds that work through peroxisome proliferators–activated receptor (PPAR) α and γ receptors. Activation of both receptors by a drug candidate will achieve more benefits and avoid side effects that could occur through working with only either one receptor. In this dissertation, chapter one will preface the experimental work covered in the next three chapters. The phytochemical work and PPAR/LXR assays of the ethanolic extract of J. communis berries will form chapter two and chapter three, respectively. Chapter two covers the extraction, fractionation, and isolation of secondary metabolites of J. communis berries. Compounds’ spectra will be presented and the structure elucidation of a major compound will be detailed. In order to investigate the biological activity of the J. communis—natural products chemistry, all tested samples in chapter three will be acquired from chapter two. Also, the chemical structure of the active compounds will be presented in chapter three. Chapter four will cover two comparison studies between the female seed cone (berry) parts of three Juniperus spp. including J. communis using four of its chemical constituents as markers. Macroscopic and microscopic studies of J. communis, J phoenicea, and J. procera will be conducted and presented in this chapter along with the HPTLC chemical fingerprinting of the same three species in addition to a quality evaluation of eight commercial samples and five dietary supplements of J. communis berries.