Interference from ordinarily used solvents in the outcomes of Artemia salina lethality test

Abstract

Methanol, ethanol, Tween 20 and dimethyl sulfoxide (DMSO) are widely used as dissolving agents in Artemia salina lethality test (aka brine shrimp lethality test [BSLT]) to screen the pharmaceutical properties of natural products. Nevertheless, there is lack of toxicity level of these solvents against brine shrimp. High concentration of these organic solvent might be toxic for this zoology invertebrate and interfere in the experimental outcomes. To avoid this, permissible concentration of the solvents used in BSLT was identified. BSLT was performed to evaluate the toxicity effect of Tween 20, methanol, ethanol and DMSO at 24 h post-treatment time point against A. salina. The suggested maximum working concentration (v/v) for DMSO, methanol, ethanol was found to be 1.25% and that for Tween 20 was 0.16%. LC 50 for the solvents were 8.5% (DMSO), 6.4% (methanol), 3.4% (ethanol) and 2.5% (Tween 20). The findings have shown a toxicity level among the solvents in descending order as Tween 20 > ethanol > methanol > DMSO. DMSO is a safer solvent to be used in BSLT compared with other tested solvents, whereas Tween 20 has been shown to be the most stringent solvent among the tested solvents. The findings are resourcefully useful to avoid interference of solvents in the assessment of natural products using BSLT.

Keywords

• Brine shrimp
• brine shrimp lethality test
• dimethyl sulfoxide
• ethanol
• methanol
• Tween 20