采用膜分离法从玉米皮中制备阿魏酸的研究
Study on preparation of ferulic acid from corn bran by ultra- and nano-filtration
-
摘要: 采用乙醇/水/NaOH溶液从玉米麸皮中提取阿魏酸,解决了提取液粘度高而难于实现膜分离的问题。最优提取工艺为:NaOH 0.25mol/L,醇水比1∶1(v/v),料液比1∶10(w/v),提取时间2.0h,提取温度75℃,搅拌速度120r/min。膜分离工艺为:利用截留分子量为5000u的超滤膜,在室温、0.10MPa下超滤,阿魏酸透过率达86.4%;透过液用截留分子量150u的纳滤膜在0.45MPa、30℃下浓缩120min,此时料液浓缩4.3倍,阿魏酸截留率为94.3%。将纳滤浓缩液经酸化、结晶,低温干燥后获得阿魏酸含量为55.8%粗制品;粗制品得率为16.5g/kg玉米皮。Abstract: Ferulic acid was released from corn bran by alkaline-ethanol aqueous solution, thus significantly decreased the viscosity of extracts and mad it easy for further purification by membrane separation. The optimal extraction technology was:one weight of corn bran was suspended in 10 volume of extraction solution (0.25mol/L NaOH dissolved in 50% ethanol solution) and extracted at 75℃ for 2h under constant stirring at 120r/min. Ferulic acid in the extract was concentrated and purified using ultrafiltration and nanofiltration successively. 86.4% of ferulic acid was recovered in the permeats when extracts were ultrafiltrated using the membrane with 5000u molecular cutoff. These permeats after ultrafiltration was then nanofiltrated using a membrane with 150u molecular cutoff, when the concentration factor reached 4.3, 94.3% of ferulic acid was maintained in the retentate, in which, the pH value was adjusted to 2.0 and the crystal of ferulic acid was obtained. After the extraction and separation processes, it was yielded 16.5g/kg of ferulic acid powder with the purity of 55.8%.