Artemia salina lethality test
Dried Artemia salina cysts were hatched in
filtered and sterilised artificial seawater (1 g
cyst per liter) at 28°C, under conditions of
strong aeration and continuous light regime
(Vanhaecke et al., 1981). Approximately 24
hours after hatching, the phototropic nauplii
were collected with a pipette and
concentrated in a small vial. Various
concentrations of extracts ranging from 0μL/
mL to 1000 μL/mL were prepared in 6x4
cell culture well plates. The concentrations
were obtained by transferring the
corresponding volume of the extracts from
the stock solution to different wells and
added with artificial seawater to make up
the final volume of 1 mL. The wells were
then gently shaken to ensure that the
compounds diffused adequately in the
aqueous solution. Three replicates were used
for each treatment and control.
An average of 10 to 15 nauplii was
transferred to each well using a pipette. Each
test consisted of exposing groups of 10 to 15
Artemia aged 24 hours to various
concentrations of the extracts tested. The
lethality was determined after 24 hours of
exposure where the larvae were observed
under stereo microscope. The number of
survivors were counted and percentages of
deaths were calculated. Larvae were
considered dead if they did not exhibit any
movement during observation.