Physiological Response of an Oil-Producing Microalgal Strain to Salinity and Light Stress

By separating and extracting algae from the collected water samples, an oil-producing diatom strain was obtained. Microscopic observation of the strain revealed that its morphological characteristics were highly similar to those of the genus Cyclotella. The cloning of 18S rDNA and phylogenetic analysis showed that the algae were clustered with Cyclotella menegheniana with a high support rate, indicating that the alga was C. menegheniana. The fatty acid content of the alga was determined and found to be mainly C14, C16, and C18 fatty acids, which were in accordance with the relevant standards for edible oil. In this study, different gradient levels of salinity and light were set to investigate the culture and bioactive substance production of C. menegheniana. The results showed that the best growth condition was achieved when the salinity was 15 g center dot L-1, and its biomass and oil content were the highest at 0.27 g center dot L-1 and 21%, respectively. The final biomass was the highest when the light intensity was 2000 Lux and the oil content was 18.7%. The results of the study provided a basis for the large-scale production of edible oils and biodiesel.

Automated summary

An oil-producing diatom strain, identified as Cyclotella menegheniana, was obtained through the separation and extraction of algae from water samples. The study showed that the strain had high morphological similarity to the genus Cyclotella. Optimal growth conditions for C. menegheniana were determined to be a salinity of 15 g center dot L-1, resulting in the highest biomass of 0.27 g center dot L-1 and oil content of 21%. The study's findings provide a foundation for large-scale production of edible oils and biodiesel.