Enhancing alpha-linolenic acid content in a promising microbiology food (Chlorella sp. L166) via low-temperature plasma

With the emergence of food shortages and other problems caused by global warming, Chlorella has attracted extensive attention as a new renewable food resource. In this experiment, low-temperature plasma (LTP) was used to promote the alpha-linolenic acid (ALA) content of Chlorella sp. The results showed that the biomass of Chlorella was the largest and the content of Chlorella ALA was the highest when the LTP treatment time was 120 s. The content of ALA in Chlorella was increased by 35.52% compared with the control group. Furthermore, the mechanism by which LTP stimulates microalgal blooms and ALA accumulation was investigated. It was found that LTP had a certain damaging effect on the cell membrane of Chlorella, reducing the pH of microalgae solution, and long-term LTP treatment would lead to the lysis and death of microalgal cells. In addition, LTP treatment increased the content of ROS and MDA in microalgal cells, and also had a certain effect on the activities of antioxidant enzymes such as SOD and CAT in microalgal cells. Research has demonstrated that the application of LTP treatment can provide microalgal strains with rapid growth rates and elevated ALA content, hence offering a viable means of augmenting Chlorella ALA levels. • Chlorella was treated with LTP at various intervals to produce a high ALA content and growth rate. • When LTP is treated for 120 s, chlorella is more likely to accumulate high value-added products such as lipids. • LTP treatment lowered the pH of the microalgae solution and damaged the cell membrane. • Impact of LTP on antioxidant enzyme activity and MDA concentration in microalgal cells.