Optimization of the Extraction Technology of Total Alkaloids from the Roots of Suaeda salsa by Response Surface Method and Its Antibacterial Activity

To optimize the extraction process of total alkaloids from the roots of Suaeda salsa and study its antibacterial activity, based on the single-factor experiments, response surface method was used to determine the optimal extraction conditions of total alkaloids from the roots of Suaeda salsa. The cylinder-plate method and the two-dilution method were used to detect the inhibitory effects of the total alkaloid extract of the roots of Suaeda salsa on three common pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis). The results showed that the highest yield of total alkaloids was 0.521%±0.04% when the ratio of material to liquid was 1:25 g/mL, the concentration of ethanol was 86%, the extraction temperature was 78℃, and the extraction time was 2.1 h. The total alkaloid of the roots of Suaeda salsa had a certain bacteriostatic effect on Escherichia coli and Staphylococcus aureus. The minimum bacteriostatic concentration was 0.4 mg/mL, and it had no bacteriostatic effect on Bacillus subtilis. The extraction process was efficient and feasible, and could be used for the extraction of total alkaloids from the roots of Suaeda salsa, and the extracts had certain bacteriostatic properties.