S-adenosyl-L-methionine（SAM）is an important metabolic intermediate in organism which is involved in many biochemical reaction.There are vast market for SAM as nutrient and drug.Our main task is carries on screening to yeast,and itsconditions to do research.The separation and purification of them were preliminary studied.SAM can be obtained by three ways:chemosynthesis,enzymatic conversion technique,as well as microbial ,of which is the primary way of industrial production.In our experiment one was choosen from four strains to produce SAM high saccharomycetes Sake,its output is the 1.71g/L.By the space-mutation Yeast Sake,was picked out 500 yeasts,then through refilter we obtained one to produce the SAM high strain,No.552 of the yeast than the originally and its production output increase 11.16%.By the fermentation,fermentation conditions Sake552 strain of did conduct a preliminary exploration. were studied and identified the best initial pH is 5.0,while SAM accumulation phase is 6.0 in shake flask;best fermentation temperature is 28℃;Best medium are 20%distilled potatoes, glucose 7%,yeast extract 1%,Urea 1.4%,L-Met 1%,KH2PO4 0.4%,K2HPO40.2%,MgSO4·7H2O 0.5%, CaCl2·2H2O 0.2%.The culture conditions of the Yeast Sake 552 in fermentor 5L were optimized, including the prescription of cultural medium,pH,dissolved oxygen,agitation speed,aeration,feeding strategy of complementarity-cultural medium in different stages.The SAM content of the Yeast Sake 552 reached 3g/L after fermentation for 4 days under the optimized conditions.We also has researched the separation and purification process of SAM and has established a preliminary technics.The procedure followed with that the cell suspension of pH2 to be frozen for 24h then to disrupt and then purify it with weak acid cation exchange resin,to crystal and deposit with methanol,to centrifugal deposition to freeze-dry it finally we got the crude SAM.
Post about "fermentation"
Xylitol is a polyol,with a sweetening power similar to sucrose and a calorie similar to glucose.is used as a nutrition and a cure for diabetes patients because can regulate abnormity of metabolism. is also used for salvaging acetone-body patients because of its resisting acetone-body effect.It can slower the productivity of fatty acid in plasma,but cannot result in the rise of bloodsugar.It is also used as a medicine for protecting liver.It has good heat-stability and never reacts with amino acids under heating,so it is confected all kinds of preparations for nutrition medicines together with amino acids.As a food,it can defend decayed tooth.Besides,it is applied abroadly in national defence,plastic and light industry.At present, is produced by chemical method in industry.But chemical method has high cost of production and serious pollution inenvironment.The production of by of hemicellulosic hydrolysates becomes a hotspot.The discourse studies the preparation of citurs fruit peels hemicellulosic hydrolysate for production of by .Firstly, citurs fruit peels hemicellulose with sulfuric acid.Then,detoxicate citurs fruit peels hemicellulosic hydrosate with S-8 macroporous adsorption resin and calcium hydroxide.Finally,studied the production of xylitol fermentation technology,identified the optimum operating parameters.Study results are as follows:1.Determined pentosan content of orange peels of different area.Among those areas,polemo peels produced in Chongqing Liangping has the highest pentosan content in those polemo peels.Orange peels Orange peels produced in Sichuan Rongxian has the highest pentosan conten in those orange peel.2.Firstly,on the basis of single factor experiment of four factors which are sulphuric acid concentration,hydrolysis temperature,reaction time and liquid-solid ratio,the optimal hydrolysis condition established by perpendicular design is sulphuric acid concentration 3%,liquid to solid ratio(mg/L)7.5:1,reaction time 2h,hydrolysis temperature 115℃.Under the condition,xylose yield of polemo peels produced in Chongqing Liangping hemicellulosic hydrolysis is 69.67%, xylose yield of orange peels produced in Sichuan Rongxian hemicellulosic hydrolysis is 65.83%.3.Through the single factor experiment,respectively inspected the effect of temperature,pH, reaction time and liquid-solid ratio on .The influence of temperature,pH,reaction time and liquid to solid ratio on detoxification of hydrolysate by S-8 macroporous adsorption resin isconsidered.The detoxification condition by S-8 macroporous adsorption resin is:adjust the pH of cellulosic hydrolysis to 10～11 by Ca(OH)2 powder,centrifuges it within 10min at the rate of 4000r/min,adjust the pH of supematant fluid to 6.0 with phosphoric acid,centrifuges it within 10min at the rate of 4000r/min.Then added the S-8 macroporous adsorption resin at the liquid-solid ratio of 5:1,35℃dealt with under 10h.Under these conditions,the polyphenol compounds, single-phenol compounds and the removal of furfural were 89.3%,92.7%and 58.1%,xylose loss rate of 15.2%.The results showed that this process can effectively remove the economic inhibitor.4.Conducted a preliminary study on fermentation of detoxified hydrolysates.The detoxified hydrolysates are fermented which are obtained with calcium hydroxide followed by S-8 macroporous adsorption resin.Examined the effect of inoculum age,inoculum concentration, culture medium volume,initial pH,fermentation temperature,sorts and addition of nitrogen source, sorts and addition of carbon source,sorts and concentration of salts on xylitol production.Concluded the best fermentation process as follow:inoculum age 10h,inoculum concentration 10mL,culture medium volume 125mL,initial pH 7.0,fermentation temperature 28℃, sorts and addition of nitrogen source:mixture of yeast extract(20g/L)and tryptone(40g/L),carbon source glucose(4g/L),NaCl addition 6g/L.Under these conditions,the higest concentration of xylitol is 28.6g/L,the percentage xylose conversion is 72.4%.
Dietary fibre is the food ingredient that is not enzymatically degraded within the human alimentary digestive tract, which is proved a good correlation in preventing and assistant therapy colonic, fat, diabetes and other chronic diseases. The present work investigates the effect of some potential use of various commercial fibres (soy fibre, sweet potato fibre, apple fibre and oat fibre) on the rheological properties of wheat flour and the final quality of breads. The following results were achieved.1. The result of rheological properties by using the Brabender Farinograph and Extenograph showed that, water absorption and stability time increased as the amount of increased, and the addition of enhanced the degree of . Apple fibre was the most prominence thereinto, while except the soy fibre, the development time and degree of softening decreased as the amount of increased. From the studies of extensographic, the result showed that energy and extensibility decreased as the mount of dietary fibre increased except the oat fibre, While the degree of resistance increased.2. From the studies of the properties of during the , the influence of fibre additions on the characteristics showed that dough with dietary fibre could make more gas during the middle of (60-120min), but this trend could not keep to the terminal. Dietary fibre addition interfere with the cross link of dough, at the same time, weaken the holding-gas capability of dough, which make the dough volume became small, especially when the amount was more than 7%. But the speed of dough increase was not influenced.3. The result of texture properties of dough and bread by using the TA-XT2i texturometer showed that, although the addition of dietary fibre increased the hardness of dough before the ferment, with the ferment progress, this effect became not evident. During this process, the Adhesiveness of dough decreased as the mount of dietary fibre. Low levels of dietary fibre caused slightly decreases in total sensory scores, and slightly effects in hardness, springiness, chewiness and resilience of breads.4. In breadmaking, dietary fibre breads had similar or slightly smaller specific volumes than the control breads, when the addition at level of 4%. The differences among the crust color of control and dietary fibre breads were significant when the addition were higher than 4% and increasing levels of fibre caused serious decreases in both sensory and texture. Regarding the effect on bread store properties, the fibre be added at level of 4% can enhance the shelf life.
To prepare the biocatalyst for biodiesel production, the strain which could producewas screened and the characteristics of were investigated. The catalyzing system was built to converse the cotton seed oil to biodiesel when the immobilized lipase was as catalyst. The results were following:A new strain, Li-38 from Xinjiang was screened which could express lipase massively. The strain of Li-38 is a member of Aspergillus niger after identified by morphology and 18SrDNA gene sequenes, and named （A. niger Li-38）.The study of characteristic indicated that the cell growth of A. niger and lipase production were partially coupled. The study of characteristic indicated that the optimal cultivation parameters for temperature and pH were determined as 45℃and 5.5, respectively; the optimized nitrogen source was 1% （w/v） of （NH4）2SO4, 3% （w/v） of peptone and carbon source was 1.5% （w/v） of rap oil; the concentration of metal ions were 0.01 % （w/v） of K2HPO4, 0.01 % （w/v） of MgS04·7H2O, 0.01% （w/v）of CaCl2, 0.01% （w/v） of NaCl2 respectively. Under the optimized conditions, activity of lipase reached the highest yield of 84.9 U·ml-1.Three methods including UV radiating, DES treatment and microwave radiating were applied in the treatment to spore and protoplast of A. niger Li-38. The results showed that the effect of the compound treatment of UV radiating and DES on them was better. The optimal parameters for spore of A. niger Li-38 were determined as the concentration of 1%DES+UV,the corresponding mutant times were 20min + 20s,15min + 30s,10min + 40s,10min + 50s,5min + 60s respectively. Preparation conditions for protoplast were optimized, which were determined as 1% of lywallzyme, 0.5% of snail enzyme, 1% of cellulose, and treatment time 40min. The optimal mutant parameters for protoplast of A. niger Li-38 were determined as the concentration of 0.2%DES+UV,the corresponding mutant times were 30min+10s,20min +20s,15min + 30s,10min +40s respectively. One mutant strain whose activity of lipase was improved 38% reached 125.36 U·ml-1. The genetic stability of mutant strain MLi-38 was good.Research about the characteristic of lipase showed the following results. The optimal reaction temperature and pH were 50℃and 5.5 respectively, and the enzyme was relatively stable under 70℃and pH 5.55.0. In all of the metal ions tested, Na+、Mg2+、Ca2+and K+ have activation effect, while Fe2+、Zn2+ and Cu2+ have inhibition effect on the enzyme and Mn2+ almost has no effect. When cotton seed was as substrate, the activation energy and inactivation energy of the catalyzing reaction of lipase were 9.8 kJ·mol– 1 and 87.975 kJ·mol– 1. The study also displayed that Km and Vmax were 9.706 mmol·L-1 and 12.11μmol·L-1·min-1.Chitosan was as immobilizing material for the immobilized lipase and the optimal parameters for were determined that the concentration of glutaraldehyde was 0.015% and the cross-linking time was 50min. The optimal reaction parameters for biodiesel production in the transesterification of cotton seed oil and methanol were determined that t-butyl alcohol was as the reaction media, the water concentration was 0.6%, the reaction temperature was 8%, the ratio of methanol and fatty acid was 0.3. Batch-addition of methanol technology was adopted, which methanol was added in 0 h, 7 h and 16 h. After reaction for 28h, the highest rate of transesterification reached 89.1%. The research for the characteristics of cross-linked immobilized lipase showed that its storage stability was better. After 12d at room temperature, the activity of lipase also retained 80% and 30 d, 46.8%. The immobilized lipase was stable at 30-70℃, pH 5.5-6.5. After immobilized lipase utilized for seven times, the ratio of transesterification was over 80%.
In this paper, the optimal seed medium, the bestmedium in flask-shaking and the batch process in 5-liter fermentor and the analysis of dynamic were investigated for production with recombinant Escherichia coli LGE35（Thr-, Met-, Kan+）. The results are as follows: The genetic markers were tested for E.coli LGE35（Thr-, Met-, Kan+）. The results showed that the genetic markers were not lost. The optimal seed medium was optimized by one-variable-at-a-time and orthogonal experiment methods. The optimum seed medium composition was found to be: sucrose 20g/L, beef extract 50g/L, peptone 20g/L, L-methionine 0.05g/L, L-threonine 0.05g/L,kanamycin 0.1g/L, calcium carbonate 20g/L. Based on the one-variable-at-a-time experiment of medium, three main significant factors of the sucrose, ammonium sulfate and yeast extract powder which affect the flask-shaking batch fermentation production of secreted by recombinant E.coli LGE35 were screened by the Plackett-Burman design. The optimal level of these three significant factors and their interactions were studied by response surface methodology. The polynomial regression model was established and the optimum medium composition was determined as follows: sucrose 71g/L,ammonium sulfate 31g/L,yeast extract powder 14g/L, MgSO4·7H2O 1g/L, K2HPO4 3g/L, L-methionine 0.15g/L, L-threonine 0.1g/L, kanamycin 0.05g/L, FeSO4 0.01g/L,MnSO4 0.01g/L,VB1 0.01g/L. The optimum fermentation condition was studied. The results showed that: temperature 30℃, pH7.0, inoculum 8%, flask-shaking speed 240 r/min.. Under optimum conditions, after the strain E.coli LGE35 was cultured 96 hours, can be produced 16.04g/L of L-arginine which increased about 32.78% more than before. Based on the flask-shaking batch fermentation condition, the batch fermentation was investigated with strain E. coli LGE35 in 5-liter fermentor. The L-arginine batch was studied based on the experimental data from the batch fermentation of 5-liter fermentor. Three kinetic models were constructed which could reflect the regularity of growth, product formation and substrate consumption in the process of batch fermentation.
Selection and Breeding of Good Avermectins Strains and the Cloning and Expressing of Integrative Vitreoscilla Hemoglobin Gene in Streptomyces Avermitilis
produced by is a type of 16-membered ring macrolide oleandrose disaccharide derivatives with structural similitude.In the of large scale and high density,oxygen supply is one of the key factors affecting cell growth and products yield.Therefore,the dissolved oxygen becomes a limiting factor to increase the production of .This research is to integrate Vitrescilla globin gene（vgb）to genome of Streptomyces avermitilis,aimed at increasing oxygen uptake rate and improving cell growing condition in order to increase the production of avermectin.S.avermitilis62 and S.avermitilis 64 screened by natural separation were stable with high ability of producing antibiotics.Their Blatiter were respectively 547μg·mL-1and 512μg·mL-1.The inactivated parental stain protoplasts fusion method was used to select high avermectin-producing stain.The total titer of Streptomyces avermitilis R08 was up to 2889μg·ml-1,and the titer of effective composition Blawas 716μg·ml-1,increased respectively by 30.9%and 39.8%compared with those of S.avermitilis 62 and S.avermitilis 64.An E.coli-streptomyces stochastic integrated plasmid pLH1001 was constructed by streptomyces stochastic integrated plasmid pSET152 and E.coli plasmid pUC19-vgb with vgb and transformed into Streptomyces avermitilis by method.Transformants were screened with the Apramycin resistance.Expression of VHb protein in transformants and the bioactivity of the expressed VHb were verified by the analysis of a CO difference spectra experiments,and there is an absorption peak at 420nm.S.avermitilis（contains or non-contains gene vgb）was cultured for 24h by secondary method,then transferred to shaking culture of in inoculum concentration of 7%（v/v）.Seven days later,by evaluating its titer,the titer of transformant is lower than before.The possible reason of the low production is the random integratation of the objective fragment to genome of StreptomycesTo optimize the fermentation medium of transformant S.avermitilisT3,Comprehensive studies were carried out about the fermentation composions.The results are as follows:Corn flour 10g/100ml,Soy flour 0.4g/100ml,Peanut flour 0.6g/100ml,Yeast powder 0.8g/100ml.Yeast extract paste 0.20g/100ml,Corn steep liquor 0.30g/100ml.The avermectin producing strain S.avermitilisT3 with the total avermectin titer was 3298μg·mL-1,and the Blatiter was up to987μg·mL-1,increased by 56.7%.
Patulin is a mycotoxin having ability in carcinogenesis, teratogenesis, mutagenesis and immunosupression. Penicillium expansum was proved to be the most important-producing fungus in apple and apple products. Microorganisms that have ability in inhibiting Penicillium expansum have great potential in biocontrol of. P. expansium. The study aimed at searching s and evaluating their potential in biocontrol of P. expansium. Stability and conditions for production of the active components were also studied to get further information on practical application. Main contents and results of the study were listed as followings:(1)154 strains of actinomycetes were isolated from soil of apple orchard, kiwifruit orchard and vegetable orchard in Yangling Shaanxi province. Four strains of s named P50,C11,C16,C60 respectively were selected by prescreening for further screening, because they had high ability in inhibiting the growth of three strains of -producing pecillium on the agar medium. Strain C16 was finally sreened out from four strains for further study on production and properties of active components because showed the greatest to three patulin-producing P. expansium, and its average inhibitory diameter is 2.33cm in agar plate tests.(2)Actinomycetes C16 was classified and identified on the basis of morphologic and physi-biochemical characteristics and the analysis of 16 SrDNA sequence. was identified as as a new species of the Genus of Micropolyspora, the Family of Micromonosporaceae, and the Order of Actinomycetale. was named as Micropolyspora.C16 and patented as the code of CCTCC M207210.(3)The compositiona of media for cultivation seed of Actinomycetes CCTCC M207210 was optimized at 20.0 maltose g/L, 2.0 yeasty protein g/L, 1.0 K2HPO4 g/L, 1.0 MgSO4 g/L, and 1.0 NaCl g/L. Nutrients of the media for were optimized by using the central composite design. Results showed the highest value of cell growth was obtained at 2.70 maltose g/100mL,0.26 yeast protein g/100mL,0.17 K2HPO4 g/100mL,0.14 MgSO4 g/100mL,and 0.15 NaCL g/100mL. (4)Conditions for liquid cultivation of Actinomycetes CCTCC M207210 were optimized by using the Box-Behnken design. Response Surface Designs was used to analyze the data. The optimal conditions were obtained at inoculum’s amount of 13.5%(v/v), initial pH of 7.4, rotation speed of 180rpm, temperature of 27.6℃, and medium volume of 125mL in 250mL shake flask. Under the optimal conditions, the highest value of dry cell weight (DCW) was predicted as 6.27 g/L.( 5 ) In order to investigate the stability of active components for inhibiting patulin-producing Penicillium, the cell-free liquid culture of Actinomycetes CCTCC M207210 was tested on its ability in inhibiting the growth of P. expansium and patulin production in agar media after being treated for a period at different temperature, pH, and ultraviolet radiation.The cell-free liquid culture was also used in apple fruits and apple juice inoculated with P. expansium to test its potential in biological controller. The liquid culture was very stable at 28oC and pH 5.7 (the nature pH) but not stable at higher temperatures and when pH was too acidic or too alkaline. The inhibiting ability of the liquid culture declined by 39.5% when it was kept at 100oC for 30min and was completely destroyed when the treatment was prolonged to 60min. Comparatively, alkaline condition (pH8 to 10) showed higher inhibiting ability than acidic condition (pH2 to 4). The liquid culture lost the inhibiting ability when it was exposed to ultraviolet radiation for 90min. The liquid culture showed the highest inhibition of rotten ratio by 25% in apple fruit which was sprinked with the liquid culture 120h after inoculation of P. expansium. The patulin production was reduced by 90% when the liquid culture was added in apple juice at ratio of 40%(v/v). Therefore, the liquid culture had great potential in inhibiting the growth and patulin production of P. expansium.
Preliminary research revealed that the content of trehalose and the specific glucose consumption rate of free yeast cells were significantly improved by inoculating wood chips with yeast cells immobilized onto them. But the reason and mechanism of this phenomenon have not been explored.In this study, the ethanol tolerance of yeast cells was evaluated directly to examine the deduction in the preliminary research.was found that the viability of free yeast cells in wood-chips-packing system was twice as high as that for no-packing system, which verified the previous deduction that the ethanol tolerance of free yeast cells in wood-chips-packing system was improved.Effects of inoculation and fermented broth as well as extract from the wood chips were further investigated to explore the mechanistic reason for this phenomenon. was indicated that the increase of ethanol tolerance was not due to the difference of inoculation. The result demonstrated that the ethanol tolerance of the free yeast cells was improved by some compounds in the broth but the compound(s) was not from wood chips. Experiment results revealed that the ethanol tolerance of the yeast cells was improved by some compounds in the broth released from immobilized yeast cells, which might be related to some microorganism multi-cellular behavior.The effect of ethanol stress on the release of the compound(s) was further investigated. was observed that the specific glucose consumption rates of yeast cells in the wood-chips-packing and no-packing systems were quite close to each other when the initial ethanol concentration in the medium was controlled at 0% or 4% (v/v). The specific glucose consumption rate of yeast cells in the wood-chips-packing system was about 10% higher than that in the no-packing system for an initial ethanol concentration of 8% (v/v). No significant difference was found in the viability of yeast cells between two systems under low ethanol condition (1.6%, v/v). These results revealed that the behavior that immobilized cells released some compounds to increase their ethanol tolerance is stress (ethanol)-dependent. This behavior of yeast cells might be an active response to the condition of ethanol stress.The effect of carrier on the release of the compound(s) was also investigated. The phenomenon of ethanol tolerance increasing for wood-chips-packing system was not observed when standard Ceramic Raschig Rings were used as carrier. The structure of wood chips was further analyzed using scanning electron microscope (SEM). It was suggested that the structure of yeast cell population might play an important role in the release of the compound(s) that can increase the ethanol tolerance of yeast cells. This feature is similar to those reported on microorganism multi-cellular behavior.Finally, the contents of trehalose and ergosterol (including free ergosterol and total ergosterol) and the plasma membrane ATPase activities of yeast cells in two systems were compared to investigate the mechanism of ethanol tolerance improvement. It was found that the contents of trehalose and the plasma membrane ATPase activities of yeast cells in two systems were close to each other at a low ethanol condition (1.6%, v/v). The contents of trehalose and ergosterol (including free ergosterol and total ergosterol) and the plasma membrane ATPase activities of yeast cells in wood-chips-packing system was higher than those in no-packing system at a high ethanol condition (11.6%, v/v). It was supposed that stress response pathways already opened was further activated by the compound(s) released from immobilized yeast cells, which caused the improvement of ethanol tolerance of free yeast cells in the system.
Improvement of Guanosine Producer Bacillus Subtilis JSIM-G518 and Studies on Optimization of Its Fermentation Conditions
as known as 9-13-D-ribofuranosyl-guanine, is an important intermediate of foods and medicines. can be used to synthesis 5′-disodium guanylate, disodium nucleotide and nucleoside antiviral drugs such as ribavirin, acyclovir. And is the main material to manufacture Sodium Triphosphate. As more and more enterprises are going to produce acyclovir, ribavirin and guanosine 5′-acid, the demand of guanosine is increasing quickly.With the goal of increasing the yield of guanosine, this study shows a mutant JSIM-GU-124-19 selected from Bacillus subtilis JSIM-G518, obtained from a production strain with protoplast mutation, which produced guanosine in a high yield after optimizing the condition. And the fed-batch and regulation of guanosine were studied. The main research and results are as follows:1. A fast and reliable method of obtaining protoplasts from JSIM-G518 which can produce guanosine is studied. The conditions of protoplast formation and the regeneration were determined through the analysis of enzyme concentration and temperature. The high-yield of protoplast is in 40 minute, 2.4 mg/mL (the final lysozyme concentration) at 36℃. The method of protoplasts is simple and effective, can improve the production capacity and performance of bacteria in a short time. The paper electrophoresis display that both contain guanosine and guanine, so in order to obtain a high-yield guanosine strain we have to gain a mutant which lacks nucleoside hydrolyase through protoplasts . At the same time a mutant with SGr, Psir was obtained, the mutant could produce guanosine 24.0 g/L, which increased by 30% of the original strain.2. The optimizations of medium and fermentation conditions for the production of guanosine by the mutant JSIM-GU-124-19 were carred out on the basis of single factor experiments and . The optimal conditions were: pH 6.4, temperature 36℃, dissolved oxygen 40%, inoculation time 10 h. The optimized medium was: glucose 12.5%, yeast powder 1.4%, (NH4)2SO4 1.5%, MgSO4 0.5%, KH2PO4 0.4%, Sodium Glutamate (MSG) 1.0%, CaCl2 0.2%, soybean digest 4.0 mL/dL, corn steep liquor1.7 mL/dL, CaCO3 2.0%. The yield of guanosine was increased to 28.3 g/L after optimization.3. The fed-batch fermentation and regulation of guanosine were studied and the flow mode and concentration of Sodium Glutamate and Dioxane were established. The experiments show that adding 0.25%Sodium Glutamate can reduce the cost of raw materials. In 30 h adding the final concentration of 100 mg/L Dioxane can short the fermentation period.
Strain No. 3 and No. 621 were two of 35 strains which isolated from nature. Their characters of morphological andof been systemic studied. Both strains have typical morphological characters of yeast, reproduction as budding and use familiar carbon resource, such as Glucose, lactose and so on. Strain No. 3 utilizes ammonium nitrogen and nitrate nitrogen. Strain No. 621 utilizes ammonium nitrogen but not nitrate nitrogen. Strain No. 3 grows at pH from 4.4 to 7.6, best of all between 6.6-7.0. Temperature ranged from 20℃-45℃, further between 28℃-30℃. Strain No. 3 grows at pH from 3.4 to 8.4, best of all between 5.2-6.4. Temperature ranged from 20℃-45℃, further between 28℃-30℃. Through 18S rDNA sequence analysis, strain No.3 is characterized as and the other strain No. 621 shows highly identical 99.0% with .In conditions 28℃, 120 r/min, 72 h, strain 3 produced 6.480 g/L from 70 g/L xylose and 43.70 % theoretical production of from 30 g/L xylose. can produce up to 21.225 g/L when incubation time prolong to 156 h from 80 g/L xylose. also can ferment 130 g/L glucose produce 47.647 g/L ethanol and reach 76.90 % of theoretical ethanol production, respectively. Compared to CK, ethanol productivity can be improve 9.91 % when add 80 g/L xylose in three times as 30 g/L,20 g/L and 30 g/L, respectively. Glucose can be first utilized in the mixture sugar medium. -fermenting can be improve when glucose exist. Ethanol of mixture with 60 g/L xylose and 20 g/L glucose is 25 % more than the total by ferment them separate.In conditions 28℃, 120 r/min, 72 h , strain 621 produced 6.059 g/L ethanol from 90 g/L xylose and 35.08 % theoretical production of ethanol from 30 g/L xylose, and 15.593 g/L ethanol from 80 g/L xylose when incubation time prolong to 156 h. It also can ferment 110 g/L glucose produce 47.647 g/L ethanol in same conditions. Glucose can be first utilized from the mixture of xylose and glucose. -fermenting can be improve when glucose exist. Ethanol of mixture with 20 g/L xylose and 60 g/L glucose is 22 % more than the total yield by ferment them separate. Compared with add 80 g/L xylose in one time, ethanol productivity can be improve 11.00 % when add 80 g/L xylose in three times as 30 g/L, 20 g/L and 30 g/L, respectively. Results of Gas Chromatography analysis to the distilled products fermented from xylose, glucose or mixture of them, showed these two strains have high efficiency production of ethanol in all of them. It judged from curve direction that ethanol yield improved when aeration level in shake flask meliorate by increase of speed of shaker.Those two wild yeast strains were found to have tolerance to high osmotic pressure. Strain 3 can grow in liquid medium with up to 12 % NaCl, 6 % ethanol or 58 % glucose, while Strain 621 can grow in liquid medium with up to 16 % NaCl, or 4 % ethanol or 61 % glucose, respectively. 10 % NaCl effected the from xylose weakly.