溶剂萃取法从褐藻浸提液中分离提取褐藻糖胶

用溶剂萃取法分离提取了实际海藻浸提液中的褐藻糖胶. 考察了接触时间、溶剂加入量及萃取剂浓度等对萃取的影响，并与从多糖配制液中的萃取情况进行比较. 考察了无机盐水溶液反萃褐藻糖胶的性能及在溶剂中加入TOA(三正辛胺)对萃取和反萃的影响，结果表明，季铵盐从实际鼠尾藻浸提液中萃取褐藻糖胶受溶剂加入量的影响很大，溶剂加入量越大，萃取率越低；而萃取时间对萃取的影响不大. 海带浸提液的萃取优于鼠尾藻浸提液，而超声破碎法有利于萃取. TOA的加入既有利于褐藻糖胶的萃取也有利于无机盐水溶液反萃褐藻糖胶. 采用溶剂萃取法制备的固体褐藻糖胶的纯度优于乙醇分步沉淀法制备的固体褐藻糖胶的纯度.

Liquid-Liquid Extraction of Fucoidan Leached from Brown Seaweeds

Liquid-liquid extraction of fucoidan leached from brown alga was studied in the present work. Effects of contact time, diluent volume added and extractant concentration were investigated. Results show that the liquid-liquid extraction of fucoidan from brown alga with N263 is rapid and the equilibrium between two phases can be reached in 5~10 min, and the extraction of fucoidan is significantly influenced by diluent volume added and the more the diluent volume added, the lower the percent extraction. This phenomenon is much different from the prepared solutions in which the diluent amount added has little effect on the liquid-liquid extraction. For different brown alga, the results show that the liquid-liquid extraction is more easily for fucoidan leached from Laminaria japonica than from Sargassum thunbergii, and moreover, an ultrasonic breakage technology is more favorable than hot acidic aqueous solutions for the liquid-liquid extraction. Furthermore, the stripping of fucoidan with an aqueous inorganic salt solution was investigated. The results indicated that fucoidan in the organic phase can be stripped by an aqueous inorganic salt solution, the percent stripping increases with increasing salt concentration and decreasing volume ratio of organic to aqueous phases. The effects of addition of TOA (tri-n-octyl amine) into the organic phase on the liquid-liquid extraction and stripping of fucoidan were also studied and it is shown that the addition of TOA to the organic phase is favorable to both the liquid-liquid extraction of fucoidan and the stripping with aqueous inorganic salt solutions. Finally, fucoidan was prepared from Sargassum thunbergii with liquid-liquid extraction technology and its purity (higher than 40%) is much higher than that (about 20%) with alcohol precipitation.