A deep eutectic solvent magnetic molecularly imprinted polymer for extraction of laminarin from seaweeds.

Magnetic molecular imprinted polymers (MIPs) based on 4-vinylbenzyltrimethylammonium chloride (VBTAC) and 4-vinylbenzoic acid (VBA) deep eutectic solvent as dual functional monomers was successfully synthesized for the specific recognition of laminarin. The MIPs were characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis, and vibrating sample magnetometer analysis. The results showed that the MIPs were spheres of a uniform size, with the surface rich in cavities and excellent superparamagnetism properties. The adsorption experiments showed that MIPs conform to pseudo-second-order kinetics and Langmuir isotherm adsorption. The maximum adsorption capacity under optimal conditions was 322.58 µg·mg-1 and the imprinting factor was 2.13. Under the optimized conditions, the limit of detection (LOD) of the developed material was 6.6 µM. Linearity of the material was obtained within the range 20-800 µM with a coefficient of determination (r2) being better 0.999. Relative standard deviations (RSDs) were less than 3.96%, and satisfactory recoveries were between 94.55 and 97.39%. The actual sample analysis manifested that MIPs could effectively separate laminarin from Laminarin japonica Aiesch.

Protective effects of 5(S)-5-carboxystrictosidine on myocardial ischemia-reperfusion injury through activation of mitochondrial KATP channels.

5(S)-5-carboxystrictosidine (5-CS) is a compound found in Mappianthus iodoides Hand.-Mazz., root, a traditional Chinese medicine used for the treatment of coronary artery disease. In this study, we investigated whether 5-CS protects heart against I/R injury. Sprague-Dawley rats were treated with 5-CS intraperitoneally for 7 days before the experiment. Hearts were perfused for 20 min global ischemia and 180 min reperfusion. 5-CS significantly inhibited an increase in the post-ischemic left ventricular end-diastolic pressure (LVEDP) and improved the post-ischemic left ventricular developed pressure (LVDP), dP/dt maximum and dP/dt minimum rates of pressure change, and coronary flow as compared with sham group. Pretreatment with 5-hydroxydecanoic acid (5-HD), an inhibitor of mitochondrial KATP channel, for 10 min before ischemia attenuated the improvement of LVEDP, LVDP, dP/dt maximum and dP/dt minimum rates of pressure change, and coronary flow induced by 5-CS. 5-CS markedly decreased the infarct size and attenuated the increased lactate dehydrogenase (LDH) level in effluent during reperfusion. Pretreatment with 5-HD also blocked these protective effects of 5-CS. 5-CS increased Mn-SOD, catalase, and HO-1 levels decreased by I/R injury and pretreatment of 5-HD blocked the 5-CS effects. Increases in Bax, cleaved caspase-3 and cytochrome c levels, caspase-3 and caspase-9 activity, and decrease in Bcl-2 level by I/R injury were attenuated by 5-CS treatment and pretreatment of 5-HD blocked its effects. These results suggest that the protective effects of 5-CS against myocardial I/R injury may be partly related to activating antioxidant enzymes and suppressing apoptosis through opening mitochondrial KATP channels.

Separation and enrichment of sibiskoside from Sibiraea angustat with magnetic surface dummy template molecularly imprinted polymers.

In this work, a novel strategy was developed for separation and enrichment of sibiskoside by dummy molecular imprinting technology and magnetic separation technology. The structural analogue geniposide was selected as the dummy template, using 4-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the cross-linking agent, and acetonitrile as the porogen. The molecularly imprinted layer was formed on the surface of the magnetic carrier to prepare dummy template molecularly imprinted polymers (DMIPs) with a core-shell structure. The DMIPs were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and Vibration sample magnetometer (VSM). The results of adsorption kinetics experiments and isothermal adsorption experiments showed that DMIPs can reach adsorption equilibrium in a short period of time and the maximum adsorption capacity can reach 14.67 mg/g. The imprinting factor was 2.08. Compared with the andrographolide, polydatin, arbutin, caffeic acid, neohesperidin dihydrochalcone and quercetin, DMIPs have good adsorption capacity for the sibiskoside. And the reusability was better. After the adsorption of DMIPs, the purity of sibiskoside in the crude extracts from Sibiraea angustata increased to 78%. It provided a basis for the further development and utilization of Sibiraea angustata as well as the separation and enrichment of monoterpenes.

Biological mechanisms of premature ovarian failure caused by psychological stress based on support vector regression.

Psychological stress has become a common and important cause of premature ovarian failure (POF). Therefore, it is very important to explore the mechanisms of POF resulting from psychological stress. Sixty SD rats were randomly divided into control and model groups. Biomolecules associated with POF (ß-EP, IL-1, NOS, NO, GnRH, CRH, FSH, LH, E2, P, ACTH, and CORT) were measured in the control and psychologically stressed rats. The regulation relationships of the biomolecules were explored in the psychologically stressed state using support vector regression (SVR). The values of ß-EP, IL-1, NOS, and GnRH in the hypothalamus decreased significantly, and the value of NO changed slightly, when the values of 3 biomolecules in the hypothalamic-pituitary-adrenal axis decreased. The values of E2 and P in the hypothalamic-pituitary-ovarian axis decreased significantly, while the values of FSH and LH changed slightly, when the values of the biomolecules in the hypothalamus decreased. The values of FSH and LH in the pituitary layer of the hypothalamic-pituitary-ovarian axis changed slightly when the values of E2 and P in the target gland layer of the hypothalamic-pituitary-ovarian axis decreased. An Imbalance in the neuroendocrine-immune bimolecular network, particularly the failure of the feedback action of the target gland layer to pituitary layer in the pituitary-ovarian axis, is possibly one of the pathogenic mechanisms of POF.