Essential oils composition and bioactivities of most prevalent species of genus Piper in Malaysia: a scope review

The genus Piperis among the most important genera in the Piperaceae family, consisting of over 2000 species and widely distributed globally, mainly in the Southeast Asian region. It is known for several medicinally and economically important species that have been used throughout their native range. Piper species have great diversity in the world's tropical regions and are represented mainly by aromatic shrubs and trees with significant production of essential oils. Essential oils are largely consumed as they are beneficial to humans as natural remedies and have been known for years to find usefulness in foods, drugs, and cosmetics. In recent years, studies on the essential oils of the Malaysian Piper species have been progressing, and many of them have reported interesting pharmacological activities. This review attempts to summarize information on the essential oils from Malaysian Piper species concerning their medicinal uses, chemical composition, and bioactivities. Information on the Piper species was collected via electronic search (Pubmed, SciFinder, Scopus, Google Scholar, and Web of Science) and a library search for articles published in peer-reviewed journals. Throughout our literature review, seventeen Piper species have been studied for their essential oil compositions in Malaysia. They were found to contain mainly of B-phellandrene, safrole, 13-caryophyllene, and aromadendrene. As for bioactivities, antimicrobial, antioxidant, and cytotoxicity activities were the most reported. This review is mainly meant to provide relevant information on the chemical components and features of Malaysian Piper species, with an emphasis on essential oils, providing guidance for the selection of accessions or species with the best chemical profiles.