Isolation And Purification Of Polysaccharides Of Edible Cactus And Study On Its No-sugar Food

Isolation and purification of polysaccharides from cladoes of edible cactus and its no-sugar food were studied in this paper.In order to select the optimum technology and conditions with the highest extraction ratio,polysaccharides from cactus powder were detected by quantum resonance spectrometer(QRS)to analysis differences of nutritional composition and pharmacological function among different extracting technologies.The raw polysaccharides,which were prepared by fractional precipitation were purified by polyamide column chromatography and Sephadex G-100 column chromatography,and then detected by SDS-PAGE.In addition,no-sugar food such as cake,preserved fruit,beverage and tablets were made from edible cactus powder and xylitol.The main results were showed as follows:Ultrasonic extraction and freeze-drying was the optimum extraction technology, which could improve extracting efficiency much,and its nutritional composition and pharmacological function indexes were also in the highest level as a whole.Water is the best extracting solvent compared with other three,and operation parameters ultrasonic power,extracting time,extracting time,the ratio of cactus to water and extracting times were 150W,20min,50℃,1:20 and 2 respectively.Except obesity,staphylococcus and E.coli,quantified value of all indexes was above 3,and Ca,Zn,antiulcer,antivirus,Vitamine C and Vitamine D reached to 7,6,5,5,4 and 4 respectively.The raw polysaccharides prepared by fractional precipitation contained flavonoids and protein,and no starch and alkaloid were detected.Free protein and flavonoids were effectively removed by polyamide column chromatography,which had a very good preservation of the polysaccharides.Single sugar fraction OFP5 and OFP6 were eluted respectively after Sephadex G-100 column chromatography,while protein was also eluted in the mean time and both of them had characteristic absorption at wavelength 280nm.The gel after SDS-PAGE was dyed by coomassie blue and thymol blue to identify the purity of the two fraction.OFP6 was proved to be a kind of homogenous proteoglycan and its molecular weight was between 35KD and 45KD.Four kinds of no-sugar food with characteristic flavor of edible cactus were developed, and correlative quality standards were constituted.