| As a kind of rare edible fungus, Truffles has abundant nutritions and superior health function. polysaccharides is the main biologically active substances in Truffles, but the research of Truffles polysaccharides reported in currently both in the domestic and foreign.With Truffles which bought in panzhihua,this study applied modern techniques to extract the polysaecharide from Truffles.We used papain and macroporous resin AB-8to isolate protein and pigments from crude polysaecharides. The preliminary study of polysacchari-des vitro antioxidant aetivity was also studied. The primary content and conclusions are as follows:1. The four different ways to extract polysaeeharides from Truffles were systemataeially studied. Based on the single-factor experiments, wih the response value of polysaccharide extraction yield and content, the Box-Behnken center-united experiment-tal design principles were used to determine the experiments condition and the response surfaces analysis.The results showed that:the optimum parameters of the tradition hot water extraction were90℃and60min for the temperature and time, the ratio of water and Truffle was33:1, under these conditions the theoretical rate of polysaccharide extraction was13.45%and the polysaccharides content was70.75%, experimental result was13.32%and the actual polysaccharides content was71.55%. The optimum parameters of the enzymatic extraction were extraction pH, enzymatic temperature, time and enzyme dosage, which were5.6,61℃,65min andl.6%, respectively. The theoretical rate of polysaccharide extraction and the polysaccharides content should be15.00%and74.19%respectively, experimental result was14.31%and the actual polysaccharides content was74.96%. The optimum parameters for ultraphonic were temperature,ultraphonic time, ultraphonic power and the ratio of water, which were36min,50℃,140W and40:1, respectively. The theoretical rate of polysaccharide extraction and the polysaccharides content should be18.42%and74.70%, experimental result was18.15%and actual content was71.04%. The optimum parameters for ultraphonic power, ultraphonic time, enzymatic pH and enzymatic time were140W,27min,6.4and20min, respectively. The theoretical rate of polysaccharide extraction and the polysaccharides content should be21.11%and71.93%, the experimental result was20.91%and actual content was72.70%.The polysaccharide extraction rate by using ultraphonic synergistic enzymatic method is higher than else methods, therefore it is the best method.2. Compared with TCA, Sevage and protease collaborative Sevage, the protein in crude polysaccharides can be efficiently hydrolyzed by proteases collaborative Sevage. According to the results of single factor and Box-Behnken center-united experimental design, the optimum condition for removing protein were that enzymatic time, chloroform:normal butanol(v/v) and shaking time were2h,5.6:1,20min, respectively. At this condition, the deproteinization rate was73.16%and polysaccharides recovery rate was85.47%.3. Macroporous resin AB-8,X-5,D101,active carbon, diatomite, kaolin and hydrogen peroxide were chose to decolorize polysaccharides. The results showed that AB-8was best decolourant among them.The optimum condition for decolorization were40℃,5h,170r/min for the decoloring temperature, time and speed of the shake bed were.The decoloring rate was76.02%and polysaccharides recovery rate was84.23%.4. Three different molecular weight components of polysaccharides were obtained from crude polysaccharides by dialysis and ultrafiltration centrifugation, which are TIP-III(mole cular weight greater thanl00KD),TIP-II (molecular weight between100KD and50K D),TIP-Ⅰ (molecular weight less than50KD).5. To study the properties of polysaccharides from Truffles, five different kinds of systems (reducing power,hydroxyl radical-OH, superoxde anion O2·,DPPH-, chelating metal ions) were used. It has strong antioxidant activity, and the ability has positive correlation with concentration.The ability of scavenging free radical from high to low was TIP-Ⅲ,TIP-Ⅱ,TIP-Ⅰ,TIP, the high molecular weight polysaccharides has better antioxidant activity. |
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