Abstract
The present study aimed to isolate β-amyrin for the first time from Laurencia microcladia Kützing distributed at Dahab Coast, Aqaba Gulf, Egypt. The successive extraction of the ethanolic extract of the alga showed that, the petroleum ether extract was the best extractive solvent which contains the isolated active compound. Based on IR, MS, and 1H NMR analyses, the active principle is proposed to be triterpens having the empirical formula C30H50O with a melting point range 191–194°C. The importance of this study was to draw attention and study the economic importance of different types of marine algae that grow on the Egyptian shores as they contain varying antimicrobial effectiveness. β-Amyrin obtained in this study from L. microcladia was known for its potent antibacterial activity and commonly used medically in many areas. These results provide evidence, to intensify the study on this L. microcladia to be used as a source of β-amyrin.