Bioactive compounds of seven seagrass species from the Western Indian Ocean identified by Gas Chromatography-Mass Spectrometry

Abstract. Maganga PY, Mbusi LD, Hamisi MI, Mgina CA, Lyimo TJ. 2024. Bioactive compounds of seven seagrass species from the Western Indian Ocean identified by Gas Chromatography-Mass Spectrometry. Asian J Nat Prod Biochem 22: 74-91. Seven seagrass species from the coast of Tanzania, namely Cymodocea serrulata, Halodule uninervis, Enhalus acoroides, Cymodocea rotundata, Syringodium isoetifolium, Thalassia hemprichii, and Thalassodendron ciliatum, were previously reported to have antibacterial activity against pathogenic microorganisms. This study presents the results of quantitative analysis of the phytocompound composition of hexane extracts of these seagrass species using Gas Chromatography-Mass Spectrometry technique. Overall, 24 known biologically active phytocompounds were revealed, with commonly found compounds being steroids, namely stigmasta-5,22-dien-3-ol acetate and 3? sitosterol acetate. On the other hand, 3?-cholest-5-en-3-ol tetradecanoate was found only in C. rotundata and T. ciliatum. Hydrocarbons (1-nonadecene and tetracosane) and a diterpene (phytol acetate) were found only in H. uninervis and T. ciliatum. In addition, pentadecanal and n-hexadecanoic acid were found in C. rotundata and T. hemprichii, respectively, while heneicosane and hexadecanoic acid methyl ester were found in T. ciliatum only. Moreover, T. ciliatum was found to contain more compounds than other seagrass species. This study reports for the first time the occurrence of fourteen compounds from seagrass species. All seven seagrass species are rich sources of phytocompounds with various pharmacological properties, such as antimicrobial, antioxidant, and antiinflammatory activities.