Identification And Purification Of Toona Sinensis Characteristic Aroma Precursors Containing Oligopeptide

Toona sinensis is a traditional Chinese food of woody vegetable,but also has a unique aroma,the characteristic of precursor substances of Toona sinensis aroma components are produced by enzymatic reaction and go through a series of changes.In this paper,we preliminary study the precursor substances of cedar's aroma components,and some progress has been made,the experimental results are as follows:1)Determine the optimization of precursor substances of Toona sinensis flavor extraction condition,get the best extraction conditions:40?,pH=7,and solid-liquid ratio in 25,300 w ultrasonic 30 min.2)By using ion exchange chromatography(001 X 7,D201),we separate two compounds from cursor substances of cedar aroma components,and identified them by TLC,NMR,IR,and then find out retention time and peak area of the two kinds of material through qualitative quantitative using LC-MS and Dns-Cl derivative technique.It is confirmed that the two compounds are ?-GIutamyI-(S-1-propenyl)thioglycine and three peptides C11H19N3O6S(Glu-Cys-Ala),the purity is 80.8%(136 mg)and 97.26%(14 mg).3)By using GC/MS and GC-O technology,we determine the precursor substances of Toona sinensis flavor is 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene,and we established the enzymatic reaction pathway of Toona sinensis flavor precursor.