Analysis Of Glucosinolates And Their Degradation Products In Traditional Chinese Medicine And Study Of Purification And Hydrogenation Of Glucoraphenin Extracted From Laifuzi

Glucosinolates are an important class of secondary compounds found in the seeds,roots,stems,and leaves of plants belonging to dicotyledonous angiosperms.They have much effectiveness as a pesticide,anti-microbial reagent and natural fumigated disinfector.As one kind of degradation products, Isothiocyanates have shown a series of biological and chemical characteristics. Besides their special flavor for condiments,they have many biological properties such as anti-bacterial,anti-carcinogenic potential.Isothiocyanates can protect DNA-damage and cancer caused by many dietary carcinogens such as polycyclic aromatic hydrocarbons,heterocyclic amines and nitrosamines.These properties have attracted the interesting of many food chemists,medicinal scientists and biologists.In the present dissertation, glucosinolates and their degradation products in traditional Chinese medicine were investigated and the purification and hydrogenation of glucoraphenin extracted from Laifuzi were studied.Glucosinolates were evaluated in 19 Chinese traditional herbs involved in 7 different families including Brassicaceae,Capparaceae,Euphorbiaceae, Phytolaccaceae,Tropaeolaceae,Caricaceae and Rubiaceae.The results showed that high content of total glucosinolates was found in some herbs of Brassicaceae and Capparaceae,while low total glucosinolates content was observed in two Rubiaceae herbs tested.In addition,the data showed that individual glucosinolates and their content varied at different degrees among the distinct species.The highest contents of cancer-protective compounds were found in the seeds of Raphanus sativus L.(glucoraphenin),Sinapis alba (sinalbin),and Lepidium apetalum Willd.(gluconapin).Usually,traditional Chinese medicines are immersed or decocted.The content of glucosinolates,isothiocyanates and indol-3-carbinol in the decoctions from the selected medicines were evaluated.The study showed that the glucosinolates still were degraded at different degrees and small amount of isothiocyanates and indol-3-carbinol were found.In order to glucoraphenin can be extracted from cheep Laifuzi and hydrogenated to glucoraphanin,one side,the process of extraction of glucoraphenin from Laifuzi was studied.The optimum extraction conditions were boiling water extracting with material and solvent ratio 1:10 for 15min for twice.The content of protein was 0.5%,reducing sugar was 5.5%and the extraction rate was more than 92%.The decoloration conditions were as following:the Amount of active carbon 4%of material quality,decoloration temperature 100℃,decoloration time 30 min with stirring.The loss rate of glucoraphenin was 11%.The last,when the alcohol concentration was 90%, the loss rate of glucoraphenin was 1.5%.On the other hand,the hydrogenation of glucoraphenin was studied.The data showed that the conditions of hydrogenation were temperature less than 100℃,and the pressure under 2MPa.When the conditions were the amount of PtO₂ 20%of crude extract quality,temperature 25℃,pressure 0.5MPa,time 9h,250r/min;or the amount of Pd/C 20%,temperature 50℃,pressure 0.5MPa,250r/min,time 4h,small amount of glucoraphenin might transform into glucoraphanin.