Astragalus root is a precious Chinese medicinal material, rich in Asarum resources, widely distributed in Northeast China, and partly in Japan and South Korea. In recent years, astragalus root has been widely used in the pharmaceutical industry. After Asarum was officially included in the "Chinese Pharmacopoeia", its application and research have attracted more and more attention from researchers. In this paper, taking Asarum as raw material as the material basis, focusing on the major needs of the national forestry economy and social development, the essential oil components in Asarum root and rhizome were obtained by microwave water distillation method. The important non-volatile components Asarum and sesamin in rhizomes were extracted by microwave-assisted method, and the process was optimized by response surface methodology. Bacterial experiments. The main contents are as follows:1. Asarum essential oil was extracted by microwave water distillation. The test showed that the water content of Asarum root and rhizome was 57.50%, and the microwave irradiation power was 540W. Under the condition of microwave irradiation time of 40min, the yield of Asarum was the highest. Oil was 15.80±0.55 mL/kg. The components of Asarum essential oil were identified by GC-MS. The results showed that 3,5-dimethoxytoluene, methyl eugenol, 3,4,5-trimethoxytoluene, and β-pinene were the main components of Asarum essential oil, and the relative content of these four components was 40.33%, 12.47%, 12.74% and 1.@ were >62%, respectively. Compared with traditional essential oil extraction methods, microwave water distillation technology has the advantages of high essential oil yield, low energy consumption during use, and short extraction time.
2. Microwave-assisted extraction of the fat-soluble components Asarum and sesamin in the extraction residue of Asarum essential oil. The optimal extraction conditions of octene and sesamin were as follows: under the experimental conditions of ethanol volume fraction of 90%, the liquid-solid ratio of 19 mL/g, microwave irradiation power of 332 W, and microwave irradiation time of 20 min, the extraction process was carried out under the following conditions: Xin and sesamin had the best extraction rates of 1.81±0.27 and 0.74±0.09 mg/g, respectively. A high-performance liquid chromatography method was established for the quantitative analysis of Asarum and sesamin: the detection wavelength was 287 nm, the flow rate was 1 mL/min, the column temperature was 28 ℃, and the mobile phase was acetonitrile-5% phosphoric acid water (50:50, v/ v) Perform isocratic elution. 3. The antibacterial experimental study of the obtained Asarum essential oil, the minimum inhibitory concentration (MIC), and the minimum killing concentration (MBC) of the five pathogenic Fusarium species are: Fusarium oats (F.) MIC=1.25 mg/mL , MBC=1.5 mg/mL; MIC=1.5 mg/mL, MBC=1.5 mg/mL; MIC=1.5 mg/mL, MBC=2.0 mg/mL Elderberry (F.).) MIC2.0 mg/mL , MBC=3.0 mg/mL; (F.) MIC 2.0 mg/mL, MBC=2.5 mg/mL.
The results show that Astragalus root and Asarum essential oil have an obvious bacteriostatic effect on Astragalus root rot fungus Fusarium, Asarum essential oil inhibits the growth and development of mycelium, destroys the shape of mycelium, and inhibits the production and development of spores. Using microwave water distillation technology can not only obtain essential oils but also take into account the efficient acquisition of fat-soluble components (Asarum, sesamin). Through single factor and response surface optimization experiments, the optimal experimental conditions for the extraction of Asarum and ephedrine were obtained. The practice has proved that the microwave water distillation cascade extraction method is an innovative, efficient, and resource-saving method.