Effect of salt stress on different components of Glycyrrhiza uralensis / 中草药

ABSTRACT

Objective: To investigate the effect of salt stress at different concentrations on the accumulative contents of glycyrrhizic acid and five components and their correlations. Methods: Annual Glycyrrhiza uralensis cultivated in the plastic flowerpot was treated with salt at different concentrations (3, 6, and 9 mg/mL). The contents of glycyrrhizic acid, total sugar, crude protein, crude fiber, crude fat and ash were determined after 35, 70, and 105 d treatment. The proportional relationships of five components and the correlation of glycyrrhizinic acid and five components were analyzed. Results: On 70 d after the treatment of 6 and 9 mg/mL salt solution, the glycyrrhizic acid content was extremely higher than that in control group. Crude protein in the treatment groups of 6 and 9 mg/mL salt solution increased significantly compared with that in control group. While total sugar content decreased significantly compared with that in control group. On 105 d, crude fat content in the treatment group of 9 mg/mL salt solution was extremely higher than that in control group. And on 70 and 105 d, the crude fat proportion in the treatment group of 9 mg/mL salt solution was extremely higher than that in control group, while the total sugar proportion was extremely lower than that in control group. The correlation analysis showed that glycyrrhizic acid content had a positive correlation with the content of crude fat and ash, while had a negative correlation with total sugar on 70 and 105 d. Conclusion: The accumulation of glycyrrhizic acid is closely related to proportion of crude protein, total sugar , crude fat and ash content. The proper salt stress could stimulate sugar metabolisms and accelerate the decomposition of the substance. All of these could promote the secondary metabolism and make the formation and accumulation of glycyrrhizic acid.