Background: The venomous jellyfish Cassiopea andromeda can produce envenomation and different
toxicological and biological effects by their nematocysts. The phospholipase A2 enzymes (PLA2) are toxic
and induce various pharmacological effects including neurotoxicity, myotoxicity, and anticoagulant
activities. The main aim of the current project was to screen the in vitro PLA2 activity of the C. andromeda
crude venom. To better understand the experimental result; a molecular docking study was also performed.
Materials and methods: The live specimens were collected from Nayband lagoon, by a trawl net, and
separation of their tentacles was done according to Bloom 's et al., method. The PLA2 activity of crude
venom was performed according to the acidimetric method of Tan and Tan. The lyophilized venom was
subjected to Gas Chromatography/ Mass Spectroscopy, and the obtained structures were used for docking
study against PLA2. The indoxam was considered as standard control.
Results: The PLA2 activity of the jellyfish crude venom was 413 ±0.08 µmol/min/mg. Analysis of the crude
venom detected seven compounds (i-vii) using GC-MS. Docking data was also confirmed the experimental
results. According to the docking results, the highest affinity [-6.7 (kcal/mol)] was observed in the compound
“Pregn-5-ene-3,11-dione, 17,20:20,21 bis [methylenebis(oxy)]-, cyclic 3-(1,2-ethane diyl acetal”.
Conclusions: A high PLA2 level was found in the venom of C. andromeda. There was a good correlation
between in vitro and in silico studies
