The Study On Determination Of 1-Deoxynojirimycin In Mulberry Leaves By Gas Chromatograph

1-deoxynojirimycin(DNJ)is a special alkaloid in the mulberry leaves.Its molecular formula is C6H13NO4,and its molecular weight is 163.As a potent inhibiter ofα-glucosidase,DNJ is used in lowering glucose level,antiviral,antimetastasis.In addition,DNJ is also a potent inhibites ofα-glucoamylase,trehalase.In the experiment,we coverted DNJ into ester with lower boiling point through chemical synthesis,gauged the DNJ content in the mulberry leaves,and campared with each other the content between 15 varieties of mulberry leaves(picked in autumn)bred by ShaanXi mulberry and silk institute.It's shown in the result that gas chromatography is advisable in the measuring of the DNJ content in mulberry leaves,and there's certain differences between different varieties in DNJ content .The different effect caused by different solvents in the extraction of DNJ was also tested .We chose certain kinds of solvents to extraxt DNJ,such as carbinol,ethanol without water,acet,chlorofoem,pyridine base.And at last pyridine base was chosen to be the solvent for the gas thromatoraphic measurement. At the same time we tested the effect of different deriving condition.Deriving solvent,time,temperature were selected as three indecies.In the end we fixed the combination solvent N,O,Bis(trimethylsily)acetamide(BSA) ; time: 5min; temperature:60℃(water bath).The effect of Gas Chromatograph condition was also tested.Four indecies were chosen : chromatographic column,temperature,gas flow,injection method.The combination we chose: chromatographic cilumn:ov-275.initial temperature:130℃for 3min and then risen to 170℃at a rate of 30℃/min ,170℃for 4min;Oven temp:200℃;Inlet temp.:180℃;gas:N2;current velocity:40mL/min;injection volume:1mL;hydrogen flame ionization detector;and software we used for chromatographic analysis were provide by QianPu Softwere Corporation, HW- 2000 Chromatographic working station.DNJ content was reckoned through standard curve methed.This method enjoys some advantages:it can simplify repetitions jobs,avoid systematic error .The equation of the standard curve:Y=18362.45C-5.22,r=0.987.The lowest concentration detected:0.12ug/mL. Recoveries test result:RSD=0.99%(n=5).Reproducible test result:RSD=1.32%(n=5)It's shown in the stability tests that standard samples and samples were stable on the whole within 8 hours.RSD were 0.87% and 1.03% respectively(n=5).Among the 15 varieties of mulberry,the highest DNJ content was 0.198%,the lowest was 0.105%,and the average content 0.159%.Through comparison we can find out those varieties with higher DNJ content,which has more medicinal value in lowering blood sugar.