Protective Effect of Ethanol Extract from Sweet Potato Leaves on CCL_(4)-Induced Liver Injury in Mice

[Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose extract group(200 mg/kg),low-dose extract group(100 mg/kg)and positive control group(2 mg/kg colchicine),with 5 mice in each group.All groups except the blank group were given intraperitoneal injection of 20%CCl 4 olive oil solution(2 mL/kg),and the blank group was given the same dose of olive oil solution three times a week.After 4 weeks,each administration group was given the corresponding dose of drugs(10 mL/kg),and the blank group and model group were given the corresponding amount of normal saline for 2 weeks.After the last intragastric administration,fasting was required,but water was allowed,blood was taken from eyeballs,and upper serum was taken by static centrifugation.Serum AST,ALT,CRP,IL-6 and SOD levels were detected by the kit.[Results]Compared with the blank group,the serum AST and ALT levels in the model group were significantly increased;compared with the model group,the ethanol extract of sweet potato leaves could decrease the levels of ALT,AST,CRP,IL-6 and increase the level of SOD in serum.[Conclusions]The ethanol extract of sweet potato leaves had protective effect on the mice with liver injury induced by CCl_(4),and its mechanism may be to protect the liver by lowering enzymes,inhibiting inflammation and antioxidant stress.

Kinetic models of peroxidase activity in potato leaves infected with late blight based on hyperspectral data

Potato late blight,which is caused by Phytophthorainfestans(Mont.)de Bary,is a worldwide devastating disease for potato.It decreased yields of potato and caused unpredictable losses all over the world.Various simple statistical methods and forecasting models have been developed to predict and manage potato late blight.Meanwhile,there is a rising need to develop prediction models reflecting peroxidase(POD)activity,which is an important health index that varies with infection and correlated with stress resistance in plants.Thus,the aim of this research was to develop kinetic models to predict POD activity.Infection-induced changes in potato leaves stored in an artificial climate chest at 25°C were analyzed using hyperspectroscopy.Four prediction models were developed by using linear partial least squares(PLS)and nonlinear support vector machine(SVM)methods based on the full spectrum and effective wavelengths.The effective wavelengths were selected by the successive projection algorithm(SPA).In this study,the prediction model developed by means of SPA-SVM method obtained the best performance,with a Rp(correlation coefficient of prediction)value of 0.923 and a RMSEp(root mean square error of prediction)value of 24.326.Five-order kinetics models according to the prediction model were developed,and late blight disease can be predicted using this model.This study provided a theoretical basis for the prediction of latencies of late blight.

Effects of Different Wall-breaking Methods on Extraction of Solanesol from Stems and Leaves of Potato

In order to extract solanesol from potato stems and leaves more effectively and improve the extraction rate of solanesol, the same batch of potato stems and leaves harvested from Guyuan, Ningxia was selected as a research object, cell wall of potato stems and leaves was broken by enzymolysis with cellulase and high- speed shearing, and then reflux-extracted with 95% ethanol. Solanesol content was determined by HPLC, and extract yield was calculated. Extract yield and solanesol extraction rate was used as an index for comparison of difference between the 2 wall-breaking methods, so as to select the optimal wall-breaking method. The results showed that enzymolysis with cellulase exhibited extraction rate and extract yield of solanesol of 91.38% and 8.02%, respectively, which were better than those under high-speed shear emulsification technique. The enzymolysis wall-breaking method has the advantages of simple operation and strong feasibility.