Study On Technology Of Extraction And Purification Of Sesamin From Sesame And Sesame Meal

Sesame (sesame) is edible which also can be used as oil. It is an important oil-bearing crop which has been planted for many centuries, especially widely cultivated in developing countries such as Asia and Africa. China is a sesame-producing country, however, there is difficulty in further processing of sesame and sesame oil for a large number of by-products namely sesame meals produced in sesame oil production process. The research relates to a method for extracting sesamin using sesame and sesame meal which is a waste in sesame oil production as raw materials. The raw sesamin was purified by column chromatography and its structure was identified after purification.Sesamin (sesamin) is a fat-soluble lignans (lignan) compounds with a variety of physiological activity. There were a lot of national reports on the sesamin extracting from sesame oil but little from sesame meal. For this reason, these research works were carried out as followed:1 A method for the determination of sesamin in sesame seeds, sesame oil and sesame seed meal was established. Sesame seeds, sesame oil and sesame seed meal were pre-treated applying organic solvent dissolving method. Qualitative and quantitative research on sesamin was carried out by HPLC method which using CH3OH- H2O (90:10, V/V)as gradient elution mobile phase with Hypersil BOS C18 5μm(4.6×250mm) column. The flow rate, injection volume of the sample and the column temperature were 1.0 mL/min, 20μL, room temperature respectively and the detection wave-length was set at 287 nm. The linear fit equation was y=14.882x-22.66,R2=0.9991(n=7)based on the integral peak area of sesamin. It was proved that the system suitability of this method well met the analysis requirements of chromatography with high separation, convenience and quickness. The average recovery of sesamin in sesame oil was 98.06% with the RSD of 0.90%, and in sesame seed meal was 97.76% with the RSD of 1.05%, which both had good accuracy and precision.2 The optimum extracting condition of sesamin in sesame oil and sesame seed meal were studied in the paper. Using the concentration of sesamin as evaluating indicators, the experimental factors such as different organic solvents, extracting times, temperature, time and the ratio between the materials and the solvents were optimized by orthogonal experiment. The optimum condition of extracting the sesamin in sesame oil and sesame seed meal were obtained, the concentration of ethanol, the extracting times , temperature, time, the ratio between raw material and solvent were 65%, 1 time, 50℃, 2h, 1:8 respectively. The repeatability experiment had shown that the extracting yield of sesamin in sesame oil and sesame seed meal were73.81% and 68.22%.3 The raw sesamin separated from sesame oil and sesame seed meal was purified by column chromatography. The purification process was obtained as followed: silica gel was used as stationary phase by dry-mounting method, while the ratio between the dry sample and silica gel was 1:50. Choosing ethyl acetate as eluting agent with elution rate of 1.0mL/min, the purity of sesamin was 81.06%. There were still small amount of sesamolin and sesame oil left in the final product according to the analysis by liquid chromatography, infrared spectroscopy and GC-MS.