Effects Of Environmental Changes On Secondary Metabolites And Antioxidant Activities Of Tetrastigma Hemsleyanum

Tetrastigma hemsleyanum belongs to the grape family of Vitaceae,which is a unique and rare medicinal plant in China,tetrastigma hemsleyanum possess anti-tumor,anti-inflammatory,analgesic and anti-pyretic properties,and it is used for the treatment of high fever,pneumonia,asthma,hepatitis,rheumatism and sore throat.In this paper,we chosed T.hemsleyanum roots tuber of artificial cultivation as the research object,established the ultraviolet determination method of flavonoids,steroids and polysaccharides,used UPLC method to qualitative and quantitative analysis the flavonoids and DPPH activity by ultraviolet spectrophotometry.Based on the content of total flavonoids,total sterols and polysaccharides,Central Composite Design(CCD)Response Surface Method experiments with four variables and five levels was designed to optimize the extraction conditions.Canoco 5.0 and SPSS 20.0 software were used to analyze the correlation between the climatic factors and secondary metabolites under diverse environment condition,and preliminarily analyzed the correlation of DPPH activity and active ingredients.In addition,using NaCl as inducer,we investigated the effects of NaCl concentration and induction time on the accumulation of secondary metabolites in T.hemsleyanum root tubers.The main results are listed as following:1.The optimum extracting condition of total flavonoids and total steroids from T.hemsleyanum roots tuber was as follow:temperature 78℃,time 97 min,methanol concentration 77%,mass ratio 10 with yields of 17.12 mg/g,relative error 0.8%for total flavonoids and 0.83 mg/g,relative error 2.5%for total steroids.The content of isoorientin 42.67μg/g;orientin 11.28 μg/g;rutin 8.71 μg/g;isoquercitin 12.03 μg/g;kaempferol-3-0-rutinoside 4.16 μg/g;astragaline 16.32μg/g;quercetin 25.45 μg/g;apigenin 10.03 μg/g;kaempferol 2.47μg/g.And,the optimum theoretical yield of polysaccharides was 44.02 mg/g,about 1.35 times as high as PH=7,when the condition as follow:temperature 80℃,time 155 min,mass ratio 31,PH=3,relative error 2.8%.2.The correlation coefficient between orientin content(Y2)and daily maximum temperature(X3)was-0.455.When the daily average temperature(X2)or the daily minimum temperature(X4)was the control variable,the partial correlation coefficient was 0.513 and 0.407,respectively.The correlation coefficient between isoquercitrin content(Y4)and daily average temperature(X2)was 0.152.When the daily maximum(X3)and lowest temperature(X4)were used as control variable,the partial correlation coefficients were greater than 0.670.The correlation coefficient of total steroids(YTs)and the daily average temperature(X2)was-0.534,when the daily minimum temperature(X4)was used as control variable,the partial correlation coefficient was 0.434.3.The correlation coefficients of total flavonoids,total steroids and polysaccharides with DPPH radical scavenging were 0.152,0.998 and 0.899,respectively.And the correlation coefficients of isoquercitrin(Y4),orientin(Y2),rutin(Y3)and quercetin(Y7)with DPPH radical scavenging were 0.601,0.555,0.431 and 0.396,respectively.In addition,astragaline(Y6)had little effect on the activity of DPPH.4.Compared with the blank group,the increments of total flavonoids(YTF),orientin(Y2),isoquercitrin(Y4),total steroids(YTS)and polysaccharides(YTP)were 10.22 mg/g,15.00 pg/g,29.81μg/g,0.47 mg/g,16.4 mg/g,respectively,and the increments of rutin(Y3)were 62.39μg/g after NaCl induction treatment of 150 mMol/L for 3 days.