Studies On The Extraction, Isolation And Identification Of The Seed Oil Of Descurainia Sophia(l.)

This kind of Chinese traditional medicine is the ripe dried seed of Descurainia sophia(L.)Webb ex Prantl, which is the plant of Cruciferae. The pharmacopoeia of P.R.China(2005 revision)specifies Tinglizi as the ripe dried seeds of Descurainia sophia(L.)Webb ex Prantl and Lepidium apetalum Willd. Descurainia sophia(L.) Webb ex Prantl is the main sources of Tinglizi at present. The Descurainia sophia(L.) seed oil contains polyunsaturated fatty acids(PUFAs), which have important functions for human health.Based on a series of literature investigations, research field of Descurainia sophia(L.) seed abroad was mainly in it's essential oil and fatty oil, while domestic research emphasised on active pharmaceutical ingredients and pharmacological effects of it. But little study on the extraction technology seed oil in Descurainia sophia(L.) was carried over the time. This research attempts to make a systematic research on the seed oil of Descurainia sophia(L.), including chose extration method and optimized the extration technical, the fatty acid composition and unsaponifiable matter constituents were also investigated in this thesis.The extraction method of Descurainia sophia(L.) seed oil was established. After comparing four extraction solvent, it was found that pertroleum ether can be used as the most suitable solvent to extract fatty oil from the seed oil of Descurainia sophia(L.). Comparison of extraction rate and physiacl-chemiacl porperties of the obtained oil by four extraction methods, it is suggests that ultrasound-assisted extraction is the best one. Specific gavity(20/4℃), rerfactive index(n²⁰), acid value (mgKOH/g), Saponification value(mgKOH/g), peroxide value(meq/Kg), iodine value (gI₂/100g) of Descurainia sophia(L.) seed oil extareted by ultrasound-assisted are 0.9176, 1.4767,3.43, 182.54, 1.65, 153.26, respectively.Ultrasound-associated extraction technology of Descurainia sophia(L.) seed oil was optimized. The effects of some operating parameters such as appropriate extraction solvent, extraction temperature, extraction time, solvent to solid ratio, and ultrasonic power and frequency on the yield of Descurainia sophia(L.) seed oil have been investigated. The optimal conditions were obtained as follows: the extraction solvent was pertroleum ether, extraction temperature was 30℃, solvent to solid ratio was 1:6(g/ml), extraction time was 40min, size of raw material was 55 mesh, extraction times of 1 time, ultrasonic power and frequency are 45kHz and 240W respectively. The average extraction rate was 31.95%.The method for analysis and identification fatty acids in Descurainia sophia(L.) seed oil was established. After Saponification and methylated by BF3/methanol the oil was analyzed by GC-MS. 29 components were identified. The analysis results indicate that the main compositions of the fatty acids in Descurainia sophia(L.) seed areα-linolenic acid(26.12%), linoleic acid(15.68%), erucic acid(12.34%), 11 -Eicosenoic acid(11.34%), oleic acid(10.75%), palmi tic acid(6.40%), stearic acid(3.03%).The total content of unsaturated acids is 86.06%, which suggest that Descurainia sophia(L.) seed oil has a developing potential as functional oil.Column chromatography and thin-layer chromatography were used to separate unsaponifiable matters in Descurainia sophia(L.) seed oil. Each portion of the unsaponifiable matters was analyzed by GC-MS. The main contents of the unsaponifable matters in Descurainia sophia(L.) seed oil are hydrocarbons, sterol,4-methylsteols and triterpene alcohols, 2,3-Oxidosqualene and tocopherol are also detected in the unsaponifable matters. All compounds exceptβ-Sitosterol were determined from Descurainia sophia(L.) seed for the first time.