Research On Extraction, Separation And Microencapsulation Of Polysaccharide In Lentinus Edodes Substratum

The Lentinus edodes, regarded as"the king of the mushroom", has been used as a kind of edible fungus for a long time in our country, due to its nutrition, tasty flavor. The Lentinus edodes is the second big edible fungus in the world, also as one of the special products in our country. According to the statistics, our country's Lentinus edodes annual output is 80,000 tons, accounting for above 80% of the global 100,000 tons, as the top one in the world.However, after Lentinus edodes was harvested, massive Lentinus edodes substratum was abandoned rather than recycled. But massive mycelia in Lentinus edodes substratum including the multi-carbohydrate compound has been wasted, therefore, in order to the comprehensively utilizing Lentinus edodes substratum, then Lentinus edodes substratum can be made up of oral or capsule, the mastication piece and so on. The purpose of this paper is to explore the bioactive polysaccharide in Lentinus edodes substratum, which will be much prospective to change"waste"into"valuable"products, reducing the cost, simultaneously also opened a new path to comprehensive utilization of the Lentinus edodes substratum that used to be abandoned in the past.This article firstly used the hot backflow, the ultrasonic wave, the microwave method the multi-carbohydrate compound carries on the extraction to the shiitake mushroom culture medium, then the most superior technological conditions was obtained. The most superior technological conditions for hot backflow law are: Soaks proposes the temperature 100℃, solid to liquid ratio 1:30, soaks proposes the time 3h, the granularity 80-100 item, under this condition, the polysaccharide in Lentinus edodes substratum reached 4.46%.The most superior technological conditions ultrasonic using wave law are: Supersonic time 45min, solid to liquid ratio 1:30, supersonic power 300W,under this condition, the polysaccharide in Lentinus edodes substratum reached 3.46%. The most superior technological conditions using microwave method are: microwave temperature 80℃, microwave power 400W, solid to liquid ratio 1:20, time 35min, under this condition, the polysaccharide in Lentinus edodes substratum reached 4.63%.Moreover, the comparative analysis on the deproteinization has been conducted using the Sevage method and the TCA method. The the Sevage method was repeated 5 times, and then protein removing rate was only 37.21%, however, the polysaccharide loss reached 23.68%. In a contrast, the TCA method was used only once, the protein removing rate reached 80.0%, the polysaccharide loss was 1.97%. Therefore, through a comprehensive analysis on the deproteinization and the polysaccharide loses, the TCA method was selected to deprotein in polysaccharide solution.The decoloring process was carried out through a comparison on the effect the activated charcoal and the hydrogen peroxide solution, and the optimized decoloring parameters for decoloration was obtained: activated charcoal amounts 1.5%, decolorization temperature 50℃, decolorization time 60min, under this conditions, the average decolorization rate of the polysaccharide reached 44.37%,and the sugar retention rate reached 63.04%. The optimized conditions for the processing of decoloriztion with hydrogen peroxide solution were obtained as follows: pH value 11, hydrogen peroxide solution amount 6%, decolorization temperature 60℃, time 80min. After repeating the confirming test, the polysaccharide of decolorization reached 50.33%, under the technological conditions, the sugar retention rate reached 80.43%Then, gas chromatogram was carried on to identify the monosaccharide composition in polysaccharide substratum, anti-tumor research was conducted in vitro. The results indicated that, the polysaccharide included glucose, galactose, monosaccharides, Li Tang, xylose, isodulcite, pectin sugar, fructose and mannose. However, the gas chromatography analysis demonstrated, there is a need to carry out a separation in order to obtain the definite monosaccharide composition. In vitro anti-tumor research, the polysaccharide could inhibit the S180 cell in vitro.Finally, the microencapsulated products were prepared. The HLB value was used to evaluate the emulsifier, and the optimized emulsion was Span-80 and Tween80. Based on the single factors, multiple-linear-regression was designed to optimize the amounts of emulsifier and the polysaccharide. Then the regression equation was obtained: Y = 0913 +0.002X1?0.06X2?0.008X1X2, meanwhile through a confirmation, the equation is not fitting. The optimized emulsifier amount was 10%, the amounts of polysaccharide 40%, and the stability approached 99%. The double-layer emulsifier was prepared using the L9(34) orthogonal design, the optimized parameters for microencapsulated products were as follows: ratio of egg abumen to maltodextrin 2:1, amounts 25%, ratio of primary emulsifier to secondary emulsifier 4:1. Based the above conditions, the microencapsulated products has the highest stability.