Eliminating the accumulation of reactive oxygen species through periodic hypoxic stress control for effective DHA production by Schizochytrium sp

•A novel periodic hypoxic stress control strategy proposed/used for DHA production.•The severe accumulation of ROS induced by oxygen-rich condition was eliminated.•The distribution of glucose to cells maintenance was maintained at the lowest level.•The highest activities of key enzymes in DHA biosynthesis metabolisms were achieved.•DHA concentration reached a highest level of 23.19 ± 1.29 g/L with this strategy.