Study On Extration, Purfication, Elementtary Structural And Properties Of Polysaccharide From Sauerkraut Juice

Sauerkraut is a traditional fermented food in northeast China, because it has a long history and unique flavor characteristics, loved by consumers. As people living standard rise, sour pickled cabbage has produced by family development for factory production, products are exported to at home and abroad. In addition to lactic acid bacteria, inorganic salts and impurities also contain bacteria fermentation to produce secondary metabolites, such as polysaccharide, protein, polypeptide and pigment in sauerkraut juice. Sauerkraut juice was thrown away after sauerkraut fermentation maturity. In recent years, sauerkraut industry is developing rapidly, sauerkraut emissions also increased, which resulted in the environmental pollution and resource waste. To our knowledge no systematic investigations concerning extraction, purification, structure analysis and bioactive of polysaccharide from sauerkraut juice have been published previously, which makes the rich and precious resources cannot be made the best and is the major roadblocks in their development for pharmaceutical fields and promoting health. This paper to fermentation mature sauerkraut juice as raw material, the sauerkraut juice spolyaccharides (SJP) crude extraction process parameters, the separation of mixed polysaccharides, purification of a single polysaccharide, and the polysaccharide group a preliminary study on the structure and properties of the designed to provides theoretical basis for the sauerkraut fermentation broth of comprehensive development and utilization. The main contents and results are as follows:(1)Optimize to the extraction process parameters of crude polysaccharide. Single factor test was used to this experiment, respectively, four factors:the concentration of ethanol, extraction of crude polysaccharide required time, extraction temperature, pH value, with comparison, the concentration of ethanol, extraction time and pH value have been proved main influencing factors. Response surface method was used to anlysis the impact and parameter values of these three factors. Get through the analysis of the model:ethanol concentration 85%, extraction time is 16 hours, the pH of solution is 8.4, and the average extraction of crude polysaccharide was obtained under this parameter reached 1.87g/L.(2) Select to the deproteinization methods in Crude Polysaccharides after extraction. Four desproteinization methods:Sevag, TCA and n-butanol mixed method, enzyme and Sevag combination method, enzyme and TCA combination method were selected by reviewing and summarizing the previous written papers. With loss ratio of protein and polysaccharide as index, enzyme and TCA combination method are chose as the best method to remove protein in this test. Using this method,94.86% of protein are revoved, polysaccharide only loss less than 20%.(3) Study on purification process of polysaccharide from sauerkraut juice. Four components SJP Ⅰ, SJPⅡ, SJPⅢ and SJPIV were gained by DEAE-52 ion-exchange column chromatography after deproteinization and dialysis. The high peak compon-ent-SJPⅡ was collected and a single symmetrical peak component-SJPⅡ-1 by Sephadex G-50 gel filtration chromatography was gained. Purity identification results showed that RDP Ⅱ was a uniform component by ultraviolet spectrum (UV) scanning and Sephadex G-50 gel filtration chromatogram.(4) Study on primary structure of polysaccharide from sauerkraut juice. Its relative molecular mass was 34190 by using high performance size exclusion chromatography (HPSEC).Infra-red(IR) spectrometry showed that component SJPⅡ-1 had typical absorption peaks of polysaccharides and it was pyranose conformational monosome. High performance Liquid Chrmatography (HPLC)result indicated that SJPⅡ-1 was composed of Fructose, mannose, rhamnose and glucose, and the moore percentage of them was 1:0.33:0.46:0.39.(5)Study on physicochemical and antioxidant activity in vitro of polysaccharide from sa-uerkraut juice.Solubility test, Phenol-sulfuric acid reaction, Feling test and Ninhydrin test were utilized to confirm that component SJPⅡ-1 was typical polysaccharide compound and non-starth polysaccharide without binding protein.With the Vc as control group, the clearance rate of superoxide radical (O2-),Hydroxyl radicals(·OH), DPPH free radical, Ferrous Ion(Fe2+)chelation and total reductive ability were measured. The results show that the clearance rate of O2- was 72.08% while the concentration of SJPⅡ-1 was 1.0mg/mL; the clearance rate of OH was 50.48% while the concentration of SJPⅡ-1 was 8.0mg/mL; the clearance rate of DPPH free radical was 52.47% while the concentration of SJPⅡ-1 was 1.0mg/mL; the clearance rate of Fe2+ chelation was 47.97% while the concentration of SJPⅡ-1 was 5.0mg/mL. The three kinds of free radicals clearance rate, Fe2+ chelation clearance rate and total reductive ability were increased with increasing concentration of polysaccharide and it showed dose-effect relationship in definite concentration range.