Extracting And Purifing Trehalose From Yeast

Trehalose is a nonreducing disaccharide of glucose. It has an excellent ability to protect biological cell (such as protein, nucleic acid, etc) from damage caused by drying and dehydration, so it has been the studying focus for scientist in the recent years. Now, in our country, there have been many studies on the base theories and the applications of trehalose, but how to produce trehalose in factory has not been solved. So the technology of extracting and purifying trehalose from yeast was studied in this paper.There are two methods to extracting trehalose from active dry yeast, by water or by ethanol solution. The best operation conditions of extracting trehalose by ethanol solution were that the proportion of ethanol in ethanol solution was 40%,80℃,1h,the proportion of material and liquid was 1/10(g active dry yeast/mL trehalose extracting liquid).Meantime, extracting trehalose by ethanol solution was compared with by water.Active carbon was a kind of effective absorbent, it was used in decolorization and removing protein of trehalose extracting liquid. To the ethanol solution extracting liquid of trehalose, the best operation condition were that pH4.1, the quantity of active carbon was 1%(g active carbon /mL trehalose extracting liquid) To the water extracting liquid of trehalose, it was determined active carbon was unfit for.As a kind of new protein of flocculant, Chitosan was wildly used in wastewater and protein recovery. Chitosan was unpoisonous and no smell. Both chitosan and protein could be recovered. To the ethanol solution extracting liquid of trehalose, the best operation condition were that pH5.0, the quantity of chitosan solution whose density of chotosan was 10mg/mL was 0.2mL/mLtrehalose extracting liquid. To water extracting liquid of trehalose, the best operation condition were that pH7.0, the quantity of chitsan solution whose density of chitsan was 10mg/mL was 0.07mL/mLtrehalose extracting liquid.Ion exchange resin n has strong ability of exchanging ion. It could be used to removing cation and anion from solution. Especially, big hole resin not only had good ability of exchange ion, but also could absorb non-ion pigment material. Ion exchange resin was used to demineralize and decolorize for trehalose extracting liquid. First, 001 × 7,001 × 7andD290resins were chosen from 12 different resins. Resins were composed to ion exchange volume. The best operation conditions were that 001 ×7(50mL)+ D290(50mL)+001 ×7(20mL),the speed of liquid was 1mL/min. Trehalose was dissolved in water well, but it has little solubility with ethanol. So ethanol was putin to trehalose extracting liquid to get crystal of trehalose.Finally, different ways of extracting trehalose from waste beer yeast were compared with.