Continuous Separation And Purification Of Bioactive Componets In Soybean Molasses

Soybean molasses is the by-product of soybean protein concentrate,which has a red brown color and sweet taste.It has been identified that soybean molasses contains bioactive components such as soybean oligosaccharide,soybean isoflavone and soybean saponins.Aim to increase the utilization and added value of soybean molasses,many scholars focus on how to separate and purify bioactive components from soybean molasses In the paper,soybean molasses was used as raw material to continuous separation of oligosaccharides,saponins,isoflavones and enzymatic isoflavone aglycones in a creative line.Then,in order to obtain ideal pure substance,the active components were purified by different purification steps.The main results are as follows:1.Study on the process conditions of continuous separation of oligosaccharides,isoflavone and saponin in soybean molasses.Firstly,the optimal conditions of extracting oligosaccharides were determined by single-factor experiments,which were 10% solid content at pH=2.5 and centrifuged at 1500 r/min for 20 min.A clear and brown supernatant was obtained.The transmittance of the supernatant was 84%,and the total sugar accounted for 53.04%.Then,the isoflavones were obtained by extraction with acetone-aqueous from the soy molasses acid precipitation.Under the conditions of acetone-water ratio 4:1 and liquid to liquid ratio 1:10 at pH=2.5 and 55? for 2 h,the extraction amount of isoflavone was(43.79 ±2.05)mg/g.Finally the isoflavone supernatant was separated by centrifuging at 2500 r/min for 10 min,and the precipitation was dried at 105? for 3 h,which could be used to extract saponins.2.Selection of auxiliary method for solvent separation of isoflavone and saponins.Comparison ultrasound with microwave assisted the separation of isoflavone and saponin,the results showed that ultrasound is more suitable for the separation.Under the conditions of ultrasonic power of 130 w for 20 min,the extraction amount of isoflavone was(64.16±5.91)mg/g.3.Optimization of extraction conditions of soybean saponins.Aim to extract saponins from soybean molasses,single-factor and orthogonal experiments were carried out to optimize the extraction.The optimized condition determined was that ethanol concentration of 75%,ratio of ethanol/water to raw material 25:1,at 70? for 4 h,and the actual yield of saponins was(167.81±6.19)mg/g.Meanwhile,the purity of saponins was 42.57%±2.34%.4.Study on the decolorization conditions of soybean oligosaccharides by activated carbon.The decolorization rate of soybean oligosaccharides was the best at the temperature and the time of45? and 15 min,with the addition of activated carbon was 3%.The decolorization rate reachedabout 96.51% ±1.04%,and the total sugar content was(77.74±6.66)mg/m L with the purity of82.93%.5.Extraction and purification of isoflavones.Isoflavones were flocculated by calcium hydroxide,then precipitated by acid,and two-phase extraction by ethyl acetate and water,in order to get pure isoflavone with the purity of 70.22% ± 2.37%.6.Study on the process conditions of preparation of enzymatic isoflavone aglycones.The optimum condition of enzymatic hydrolysis preparation isoflavone aglycone was obtained through single-factor experiments.Under the optimal condition: enzymatic temperature of 50?,ultrasonic power of 92.5 W,enzymatic p H=4.2,enzyme volume of 120 U/g isoflavone,and hydrolysis 25 min,The enzymatic hydrolysis rate reached 78.60%±0.8% through this progress7.Purification of soybean saponin by column chromatography.The purity of saponins reached to 73.21%±1.05% by AB-8 resin column chromatography and 0~99% ethanol gradient elution.