Studies On The Extraction, Purification And The Pilot Procedure Of Oat β-glucan

Oatβ-glucan is a kind of non-starch polysaccharide which is usually concentrated in the inner aleurone cell walls and subaleurone endosperm cell walls covering the ranges of 3-7%on a dry basis.Naked oat is the speciality cereal in China.This paper studied on the analysis methods,extraction,purification and the pilotscale extraction procedure ofβ-glucan from naked oat bran.A spectroscopic method for determination ofβ-Glucan from oat was established.The determination conditions were as follows:the optimal pH 8.0,reaction time 30 min, reaction temperature 20℃and the maximum absorption wavelength 545 nm.The accuracy and recovery tests demonstrated that this method is simple and feasible.Factors that had influence on the yield ofβ-glucan were mainly considered,including extraction solvent,extraction temperature,reaction time,pH,the solvent-solid ratio and extracting time.On the basis of single factor experiments,the two times rotated regression was used to search the optimum extracting parameter.The optimum conditions of water extraction were:the optimal pH10.0,temperature 70℃,reaction time 60min,the solvent-solid ratio1:15 and extracting two time.In these optimum conditions,the yield ofβ-glucan was 8.47%.The extract solution was successively treated by enzymatic removal of starch, de-protein,de-color and precipitation of water-soluble polysaccharide with different precipitator.The result showed that,the optimum dosage of o-amylase was 40U/50mL;the isoelectric precipitation of protein residue is the best method,by which the protein-removed rate was 80.6%and the loss rate ofβ-glucan was 18.15%;the adsorption colophony of AB-8 was used to remove the color ofβ-glucan and at the same time adopt ethanol as the precipitator and the terminal concentration was 60%.The crudeβ-glucan was purified by using polyamide adsorption chromatography as well as Sepharose CL-4B gel-filtration column chromatography.Two components POG-1 and POG-2 were obtained.The method of UV showed that POG-1 wasn't a homogeneous fraction.The purity of POG-1 was approved by UV and HPLC detection after adsorption chromatography and gel-filtration chromatography.POG-1 molecular weight was 678297 by HPLC analysis.According to the optimum conditions of extraction in laboratory scale as well as the realizable of mass-produce,designing a pilot extraction procedure ofβ-glucan from oat bran and extracting a mass ofβ-glucan.The result showed that the purity of crudeβ-glucan extract by the pilot procedure can reach 68.72%.The cost ofβ-Glucan is approximately 50 Yuan per kilogram.These demonstrated that this method suit to industrialization manufacture.