Abstract:
Biological and chemical diversity of marine habitats provide a sizeable reservoir of novel
bioactive compounds with therapeutic usage. Marine sponges (Porifera) are ranked at the top of
hierarchy, with respect to the discovery of an array of bioactive compounds. We investigated
anti-inflammatory activity of five marine sponge (Class Demospongiae) crude extracts, by in
vitro protein denaturation and nitric oxide (NO) radical scavenging assay. Sponge material was
collected from Dehiwala, Colombo (WL/3/2/14/17) and identified by morphology, skeleton and
spicule analysis. The sponge crude extracts (SCEs) were prepared by methanol/dichloromethane
extraction, followed by filtration and rotary evaporation. The zoo chemical analysis was carried
out to investigate major chemical compounds present in SCEs. Concentrations of 100, 50, 25,
12.5 and 6.25 μgml-1 of SCEs were prepared by serial dilution. In vitro assays of egg albumin
denaturation and Griess method were carried out to investigate the anti-inflammatory activity of
the SCEs by means of protein denaturation and nitric oxide radical scavenging activity
respectively while the percentage inhibition (IC 50) of each activity was calculated. The sponge
species were identified as Stylissa sp. (SP1), Stylissa cartetrri (SP2), Axinella sp. (SP3),
Phakellia sp. (SP4) and SP5 belongs to family Axinellidae. They contained alkaloids and
terpenoids (SP3, SP4 & SP5), saponins (SP1 & SP4) and unsaturated sterols (SP3 & SP4).Three
SCEs of SP2, SP3 and SP5 inhibited egg albumin denaturation with IC 50 value of 22.74, 3.98
and 63.67 μgmL-1 respectively indicating anti- inflammatory activity. In each, IC50 values were
lower than that of the standard reference drug (147.02 μgml-1). The SCE of SP4 showed antiinflammatory
activity, yet was not dose dependent. The SCE of SP2 indicated nitric oxide
radical scavenging activity with IC50 of 44.65 μgml-1, which was more potent than the reference
drug (126.07 μgml-1). In toto, this pilot study prove that the tested crude extracts of five selected
marine sponge species (Stylissa sp., Stylissa carterri, Axinella sp., Phakellia sp., and Family
Axinellidae) possess in vitro anti-inflammatory properties with respect to egg albumin
denaturation and Nitric Oxide radical scavenging activity. It further warrants the chemical
characterization of these SCEs and a comprehensive study using in vivo and ex vivo models.
