Abstract:In order to understand the effect of liquid cultures on thallus of Huperzia serrate (Thunb.) Trev. in vitro, the changes in thallus growth, huperzine A accumulation, antioxidant enzymes activities and endogenous hormones were studied cultured on different dosage of liquid medium. The results showed that the huperzine A contents had significant differences among different dosages of liquid medium. The huperzine A content could reach up to 3 115.159 μg L-1 with 15 mL medium, which was 2.20 times more than the control. The superoxide dismutase activity of thallus cultured in shallow liquid was higher than that of the control, the activity of peroxidase was higher than that of the control at early stage, while did the activity of catalase at later stage. The contents of endogenous hormones IAA and GA were lower than the control, while ABA content was higher than the control. Therefore, it was suggested that the ability to produce HupA was high in thallus in vitro of H. serrata cultured with shallow liquid medium, the HupA content had relation with the content of endogenous hormone ABA, and the activities of three antioxidant enzymes in thallus had collaborative enhancement effect during growth stage.