| Perigord Truffle symbiotic with trees is a kind of medicine and food bacteria, which is famous for its unique and delicious taste, special smell and the higher medical care value. So far, the domestic and foreign researches only confine to the Truffle artificial planting and simple processing, and the researches on active ingredients of it are little. Truffle which contains special aroma and active polysaccharides has special curative effect on boosting sexual ability, antitumor, aging and so on. It can be widely used in the food industry, chemical industry and pharmaceutical industry. Therefore, this experiment in the system of Truffle aroma and polysaccharides Truffle resources of full use opened wide prospect of market.The article is based on experiences of T.huidongense. The aroma compounding of T.huidongense was extracted by simultaneous distillation extraction (SDE), ultrasonic-assisted solvent extraction (UASE) and solid-phase micro extraction (SPME), and then investigated by GC-MS. Meantime, the isolation, purification, physiochemical and structural characteristics of polysaccharide from T.huidongense was also investigated. The result of experiment was showed as follow:1. Truffle aroma compositions extraction and analysis identification:(1).Using three methods which are ultrasonic solvent extraction, simultaneous distillation and extraction, solid-phase micro-extraction to extract the aroma of T.huidongense, and under the same conditions using gas chromatography-mass spectrometry combined with computer retrieve to analyze and identify the constituents of truffle aroma, the article shows us the result that by using ultrasonic solvent extraction method, the extract was isolated 80 peaks, and identified 65 kinds of compounds which occupy the total content of 93.59% of the identified components. With simultaneous distillation and extraction method, the extract was isolated 91 peaks, and identified 67 compounds which occupy the total content of 90.45% of the identified components. With solid-phase micro-extraction extraction method, the extract was isolated 64 peaks, and identified 50 compounds which occupy the total content of 75.15% of the identified components. Pros and cons of an integrated three methods, the article gets a conclusion:SDE (simultaneous distillation extraction) in three methods is the best, at the same time with UASE and SPME for the auxiliary. The three methods complement each other, in order to have a comprehensive measuring analysis about chemical constituents of the aroma of truffle; a total of 142 kinds of flavor substances isolated. The common contains ingredients have 10 kinds of aroma compositions,23 kinds of main aroma compositions, and then the experiences had further analysis on aroma compositions, and showed that aroma compositions are mainly formed by enol, Alkenes, esters, acids and phenols.2. The truffle polysaccharides extract research:using acid and alkali extraction which configured different concentrations of liquid and baptized by ultrasonic extraction. The results found:cooperated with ultrasound neutral water extraction, the degree of the proposed polysaccharides flocculation in the two methods above was very low, and was not easily separated from impurity, which was low in efficiency, so these two kinds of methods were not for research. Based on single factor, using response surface methodology to optimize the major process parameters to get the regression model and the analysis of variance to optimize the combination of the yield of polysaccharides, ultrasonic processing time, extraction temperature, liquid-solid ratio and ultrasonic power. The results showed that the model fits well and experimental error is small. It's right to choose the model. Its quadratic equations for:Y=3.30+0.14X1+0.08X2-0.056X3+0.27X4+0.11X1X2+0.15X1X3-0.18X1X4+0.048X2X3-0.5 1X2X4+0.022X3X4-0.14X12-0.25X22-0.50X32-0.41X42.Optimal conditions for the optimal parameters are ultrasonic power (105 W), ultrasonic processing time (40 min), liquid-solid ratio (25:1), and extraction temperature (75℃). Under these conditions, the yield of polysaccharide truffles reached 3.48%.3. Water-soluble polysaccharide (WPST) purification research:Two water-soluble polysaccharides (PST-W and PST-A) were isolated and purified by using ultrasound-assisted extraction, ethanol precipitation, dialysis, Sevag and enzymatic protein removal, DEAE-52 cellulose and Sephadex G-100 column chromatography. The final extraction respectively is 0.12% and 0.41%.4. PST-A, PST-W physicochemical properties of the research:These polysaccharides were identified by high performance liquid chromatograph (HPLC) and found to be a highly homogeneous polysaccharide, which did not contain proteins and nucleic acids, Are soluble in water, insoluble in organic solvents with a relative molecular mass of 128059.9 Da (PST-W) and 729140.5Da (PST-A) rather than starch.5. The structure of PST-A, PST-W research:By means of IR spectroscopy, high performance liquid chromatograph (HPLC), methylation analysis, nuclear magnetic resonance (NMR), and the polysaccharides fraction was characterized structurally, and the results indicated that both PST-W which was composed of seminose, galactose and glucose, and PST-A which was composed of glucose were furanose.The mole ratio is monosaccharide PST-W:Glc:Man:Gal=3.01:1.00:0.96. With further verification by methylation analysis and nuclear magnetic resonance (NMR), it was presumed that the glucose units of PST-A was only joined by a-D-(1→6) bond, and its molecular structure is [→6)a-D-Glcp (→6)a-D-Glcp(1→]n.(In view of the PST-W low extraction, This experiment on only for PST-A methylation and nuclear magnetic resonance (NMR) analysis.)Based on comprehensive study of truffle aroma and polysaccharides, the extraction technology of truffle aroma is optimized; truffle polysaccharides extract, separation and purification of optimum route got sure. This experiment is tasted for the extraction of polysaccharides system comprehensive physical and chemical properties research, PST-An identified alpha D-(1-6) connection linear glucan.
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