After completing his PhD program at University of Georgia, USA in 1979, he joined University Putra Malaysia (UPM, previously known as University of Agriculture, Malaysia)as Lecturer in the Department of Chemistry. In 1986 he was appointed as the Head of the Department of Chemistry and later became the Deputy Deanof the Faculty of Science. His last appointment in UPM was the Head of the Laboratory of Natural Products. Currently, he is holding a Professorial Chair at Taibah University, Madinah al-Munawarah, Saudi Arabia. In his capacity as lecturer and researcher, he has written, translated and edited several books for university education, general public and researchers. He has published more than 210 research papers in various journals and holds 3 patents. His research interest includes the chemistry of natural products, drug synthesis and design, as well as the use of metabolomics in biological science research.