球等鞭金藻多糖的微波萃取工艺

采用微波法，通过单因素试验研究pH值、微波功率、萃取温度和萃取时间对球等鞭金藻多糖提取的影响。在此基础上，通过正交试验进一步优化多糖的微波提取工艺。最后，比较微波提取法和热水浸提法制备的球等鞭金藻多糖样品的红外光谱，并测定样品中蛋白质和多糖含量。单因素试验结果表明，pH值、微波功率、萃取温度和萃取时间均能显著影响球等鞭金藻多糖的提取。正交试验结果表明，微波法提取球等鞭金藻多糖的最佳工艺为pH9、微波功率600W、萃取温度90℃、萃取时间20min。微波提取法和热水浸提法制备的多糖产率分别为96.8mg/g和47.7mg/g。其中，前者蛋白质和多糖含量分别为1.08%和43.6%，后者中蛋白质和多糖含量依次为1.18%和22.1%。微波法与热水浸提法制备的多糖具有相似的红外光谱，表明微波提取法并不会破坏多糖结构。综上所述，在球等鞭金藻多糖提取过程中，微波法明显优于热水浸提法。

Optimization of Microwave-assisted Extraction of Polysaccharides from Isochrysis galbana

One-factor-at-a-time method and orthogonal array design were employed to optimize four process conditions for microwave-assisted extraction of polysaccharides from Isochrysis galbana such as pH, microwave power, temperature and extraction time. One-factor-at-a-time experiments showed that each of the four conditions had a marked effect on polysaccharide extraction, and their optimal levels were identified by orthogonal array design to be: pH 9, microwave power of 600 W, extraction temperature of 90 ℃ and extraction time of 20 min. Under these conditions, the extraction rate of crude polysaccharides was 96.8 mg/g compared with 47.7 mg/g for hot water extraction, and the contents of protein and polysaccharides were respectively 1.08% and 43.6% in the crude polysaccharide sample obtained compared with 1.18% and 22.1% for hot water extraction. The crude polysaccharides obtained by both extraction methods revealed similar IR spectra, demonstrating that microwave did not destroy the chemical structures of polysaccharides. In summary, microwave-assisted extraction is greatly superior to hot water extraction.