Screening of crude extract compound from the gills of female mud crab, scylla serrata

The research among marine organisms is gaining its momentum. This is due to the fact that most of the terrestrial organisms has already been discovered their potential and there is a need for new sources of bioactive compounds. The mud crab is a good choice because it is readily available in Malaysian waters. There were a few studies that have been carried out on its haemolymph and it has been discovered to exhibit antibacterial and antifouling activities. The other parts of the mud crab were discarded which is a waste of resources because they may also contain bioactive compounds. In this study, the gills of the mud crab were placed in different solvents of different polarity; methanol, acetone and ethyl acetate as a means of extraction. Then, they were preserved using liquid nitrogen and subjected to serial dilution. Antibacterial and antifouling assays and thin layer chromatography (TLC) method were carried out. In conclusion, the Disc diffusion test (DDT) indicated that antibacterial activities of the crude extract were most effective for Salmonella typhimurium while it is least effective towards Staphylococcus aureus. Low levels of antifouling activities were observed to be slightly higher in Gram-positive bacteria in comparison to Grarn-negative bacteria. The thin layer chromatography (TLC) indicated that the compounds that exist in the sample ranges from polar to non-polar substances. This study will act as a preliminary study in discovering the potential of mud crab as a new source of bioactive compound.