Investigation of Ethyl-methanesulfonate (EMS) Treatment as A Mutagenesis Approach Toward the Enhancement of the Production of Carotenoids in Chlorella vulgaris

Abstract

As the human population grows, the demand for organoleptic properties in food has linearly increased, including the use of harmful synthetic colorant. Therefore, carotenoids, as a secondary metabolites and natural compounds, can be used as an alternative to natural food preservatives. They are also attributed to antioxidant properties which are beneficial for human consumption and health. This research aims to find the optimum EMS concentration as a mutation agent for Chlorella vulgaris, a microalgae species that are able to accumulate high carotenoids content. To further improve the carotenoid content, chemical mutagenesis was used to create random modifications in the algal base pair, specifically ethyl-methanesulfonate (EMS). An axenic single colony C. vulgaris obtained was upscaled for the EMS treatment, and 57% cell viability was the lowest percent cell viability obtained, treated with 200 mM EMS. However, there was an insignificant difference of carotenoid accumulation in C. vulgaris treated with 200 mM EMS compared to untreated C. vulgaris. The result suggests that the insignificant effect might be due to the percentage cell viability selected that were still in the sublethal concentration of the EMS, which does not totally induce the genetic variations, compared to the favored cell viability of 5-10%. Furthermore, the comparison of the carotenoid content through the extraction process and analysis should be considered to validate the current result, and lower cell viability should be further selected and investigated.