Abstract:
In recent years research on the chemistry o f seaweeds (or more generally marine algae)has experienced a tremendous increase due to the need for compounds possessing bioactivities o f possible pharmaceutical applications or other potential economic properties. Marine algae (Seaweeds) are known to produce an incredible diversity of secondary metabolites some o f which show potent anticancer, antibiotics, antiviral antimicrobial, anti-inflammatory, anthelmintic, antinmgal, antitumor and insecticidal
activities. Considerable amount o f work have been done on seaweeds around the world.
However, the biomedical potential o f the rich Sri Lankan seaweeds remains largely
unexplored. Due to this reason Natural product program o f the Institute o f Fundamental
studies initiated a project on chemistry and biological activity studies o f Sri Lankan
seaweeds.
Padina pavonica, brown algae was collected from the coastline o f Arugambay at Ampara
District in the Eastem Province in Sri Lanka. Plant material was cleaned, washed with
fresh water, air dried, powdered and extracted with MeOH using a sonicator. Dried
MeOH extract was successively fractionated with Hexane, Chloroform and Ethyl acetate.
After that the dried Hexane fraction was subjected to column chromatography with
normal Silica and C-18, followed by Preparative Thin Layer Chromatography (PTLC) to
gave three pure compovmds but the amount o f these compounds were small and needed
high sensitive instruments to analyze them.
As I was not in a position obtain the H NMR o f isolated compounds, for familiarization
o f spectroscopic techniques, spectral data o f a compound isolated fiom green seaweed,
Ulva lactuca was analyzed ('H and 13C NMR, HMQC and HMBC Spectrums) and its’
structure was proposed as 9-octadecenoic acid (Oleic Acid).
