Magnetic nanoparticles immobilized thrombin ligand fishing to screen thrombin inhibitors in natural products.

In this study, thrombin was immobilized with magnetic particles modified by glutaraldehyde. The changes in secondary structures of immobilized enzyme revealed an increment in conformational rigidity and stability, which can be reflected in temperature and pH stability as well as the tolerance of organic reagents. The optimal reutilization times of magnetic particle immobilized thrombin were 7 times, and the half-life of enzyme activity preserved at room temperature was 5 days, which was 2.5 times higher than that of free enzyme. Ligusticum chuanxiong and Anemarrhenae Rhizoma with high enzyme inhibitory activity were selected for primary screening, and six potential inhibitors of thrombin were identified by HPLC/MS. The results showed that three compounds in Anemarrhenae Rhizoma had better predictive thrombin inhibitory activity. Through the in vitro thrombin activity inhibition experiment, it was also verified that mangiferin and neo-mangiferin had an ideal thrombin activity inhibition effect, which was consistent with the results of molecular docking.

[Research on improving memory impairment of blue lavender volatile oil].

In order to study the potential application value of lavender volatile oil (LVO), the chemical composition of the volatile oil of lavender was analyzed by GC-MS, and the mouse model of Alzheimer's disease (AD) was established. Additionally, the antioxidant enzymes activity of T-SOD, GSH-PX, CAT and MDA content were studied. Experimental results showed that 55 kinds of chemical constituents including terpene, terpene alcohol and ester compounds from LVO were identified, and the content of linalool and linalyl acetate was the highest, accounting for 49.71% of the total volatile oil. The ability of mouse platform memory was improved significantly. The levels of GSH-PX, CAT and T-SOD of mouse brain tissue in the treatment group were significantly higher than those in the model group (P<0.05). The level of MDA reached the maximum value in the model group, while there was no notable difference between the levels of MDA in the drug group and the normal group. The result indicated the significant oxidative activity of LVO, the possibility of induced oxidative stress reduction in neurons, and the reversal effect of memory acquired disorder.

[Study on the extraction of the active component in Atractylode macrocephala with ultrasonic wave technology optimized by the response surface method].

OBJECTIVE: To create Atractylode macrocephala inspissation decoction pieces. The effect of ultrasonic wave on extraction of the active components in A. macrocephala was studied in a water solution. METHOD: The factors including the ratio of material to liquid, ultrasonic power, ultrasonic time, soaking time, particle size etc, were studied. The best extraction method was found through the response surface method. RESULT: The best extraction method was found as follows: the granularity of material 0.1 mm, the repetition times of ultrasonic process 3 times, the soaking time before the ultrasonic process 30 min, the ratio of liquid to material 10:1, the soaking time after the ultrasonic process 2.6 h, the time of the ultrasonic wave 15.5 min, the power of the ultrasonic wave 531 W, the rate of reservation of active components 88.5%, the rate of inspissation 1.6. CONCLUSION: The ultrasonic wave can used in the extraction of the active components in A. macrocephala and a model equation that can be used to predict the experiment was get through the response surface method.