Preparation of Crude Ethanolic Extract
An alternative procedure developed by other related studies was adopted with some modifications [19, 20]. Remaining samples were air-dried for about 2-3 weeks. Dried samples were pulverized using a sterile electric blender and soaked in pure absolute ethanol for at least three days. Solution was filtered and concentrated using rotary evaporator. Thirty milligrams from freeze-dried decoction were dissolved in 3 ml seawater to obtain the stock solution of the decoction. On the other hand, DMSO was used as emulsifying agent to dissolve the ethanolic crude extract and was added with 3 ml of seawater to obtain the stock solution of the crude ethanolic extract. From the stock solution, 100, 500, and 1000 ppm concentrations were prepared by the addition of 50 μL, 250 μL and 500 μL of the solution, respectively to 20 mL test tubes all diluted to 5ml with seawater