Isolation, characterization and antimicrobial assay of some components from the chloroform extract of Lobophyton crassum

• Main Author: Urubio, Gracia
• Format: text
• Language: English
• Published: Animo Repository 1995
• Subjects: Corals; Microbiological assay; Microbial sensitivity tests; Extracts; Chloroform; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1668; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=8506&context=etd_masteral
• Institution: De La Salle University

The chloroform extract of the soft coral Lobophyton crassum was found to contain two isolates with potent antimicrobial properties. The first isolate, Isolate I was partially elucidated based on the spectral evidences (IR, 1H nmr, 13C nmr). Comparison of its 13C nmr chemical shifts with that of 3 beta-hydroxylated steroids, and of its 1H nmr with that of a gorgosterol, the major components of Isolate 1 is either an isomer or derivative of gorgosterol. The exact structure of its side chain could not be determined due to presence of impurity. The second isolate, Isolate 2 was structurally elucidated based on the spectral evidences (IR, 1H nmr, 13C nmr) and comparison of its 13C nmr chemical shift with a known diterpene. The isolate has a molecular formula of C20H30O2 and it is systematically named as 2-[(E,E,E,)-7',8',12'-trimethylcyclotetradeca-1',3',11'-trienyl]propan-2-ol.Both isolates exhibited antimicrobial activity against six of seven test organisms. Of the six text organisms, Isolates 1 and 2 were most active against M. aevium exhibiting a complete zone of inhibition measuring 24.0 mm and 20.6 mm, respectively.