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Erythritol (Erythritol) four-carbon sugar alcohol, is a naturally occurring chemical name 1,2,3,4 - Tetrabutyl alcohol, MF C 4 H 10 O 4 , molecular weight 122.12, melting point 126 ℃, boiling point of 329 to 331 ° C, the appearance of a white crystalline powder, comminuted, soluble in water will absorb more energy, the heat of solution-97.4J / g, using a cool mouthfeel characteristics. Erythritol, a very wide distribution in nature contain erythritol, seaweed, mushrooms, fruits and melon, grapes, peaches, etc., due to bacteria, fungi and yeast can also produce erythritol, so Chek The erythritol there in wine, beer, soy sauce and other fermented foods. Erythritol is a moderate sweetness bulking agents, and the sweetness of sucrose, 60% to 70%, is not mutated Streptococcus use, anti-caries, does not participate in the glucose metabolism and blood glucose changes, suitable for diabetes, obesity, and heart cerebrovascular disease human consumption. Heat resembles the taste of sucrose but close to zero, the high amount of physiological tolerance, functional health food ingredients can be used as a low-calorie, very broad application prospects. The purpose of this study is to use UV mutagenesis screening from the laboratory to the erythritol bacteria breeding superior strains and protoplast fusion technology with different strains of higher production Erythritol hypertonic Candida The yeast strains fusion obtained erythritol yield engineering bacteria and depth study of the growth conditions of the strain. Strains activated while the collection and screening method for the detection of the erythritol, worked out a use of special color toner tlc detection methods, i.e. by standard sample gradient quantitative point samples, create a standard thin-layer plate, samples in the experiment simply thin layer plate chromatography results with standard board control Erythritol samples preliminary qualitative and quantitative analysis. The great convenience yield erythritol strain detection and cell fusion experiments in mutant strains detected purpose fusion strains fusant. The orthogonal experimental of UV mutagenesis yield erythritol bacteria, to determine the of UV mutagenesis Ho photoreactivation alternately mutation breeding conditions; protoplast fusion the overproducing strain obtained from the temperature, culture time and pH growth conditions studied, and finally establish yielding erythrose alcohol strain RH-UV-L4-F9 culture conditions for the culture temperature of 30 ° C, culture time 6D, the initial pH of the medium is from 5 to 6, and the glucose concentration was 30%, a nitrogen source for 0.5% yeast extract and 0.1% urea. Erythritol fermentation broth after cultivation of the above conditions sugar alcohol content 120.6mg/ml, and 3.61 times more than the starting strain. The conducted studies on the various factors that affect the rate of the formation of protoplasts, the regeneration rate during the experiment, as well as the parameters affecting the electric fusion. The results prove that the enzyme concentration, hydrolysis time, optimum temperature, pH value, osmotic stabilizer selection protoplast formation rate, regeneration rate has a significant impact in each influencing factors on the basis of single factor experiments to determine a protoplast formation rate, the regeneration rate higher optimum conditions. At the same time by the
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