原生动物阴道毛滴虫的酵酶长寿保障基因LAG1同源基因克隆和序列分析(英文)

为了探讨寄生性原虫阴道毛滴虫细胞生长和衰老相关基因 ,作者从阴道毛滴虫的cDNA表达文库中分离出一具 91 0碱基对的cDNA克隆 ,其编码框长 834bp ,推测蛋白质序列有 2 77个氨基酸。序列分析显示该克隆与酵酶长寿保障基因LAG1同源性最高 ,其氨基酸序列中含有LAG1及其同源基因保守的Lag1结构域和TLC结构域以及 6个跨膜螺旋区和一个C 未端的内质网保留信号域。因此推测该克隆系酵酶LAG1的同源基因 ,该基因可能参与阴道毛滴虫的神经酰胺生物合成以及调解细胞的生命期或细胞衰老。该基因的基因组DNA与其cDNA序列一致 。

酵酶素对断奶仔猪增重效果的影响

选用 48头 45日龄断奶仔猪 (长白×约克 )随机分为试验组与对照组 (每组各 2 4头 ) ,试验组于基础日粮中添加 2 %的酵酶素 ,对照组不加 ,试验期 30天 ,结果表明 :试验组比对照组日增重提高 9.1 4 % (P <0 .0 5 ) ,饲料利用率 7.5 % ,平均毛利润增加 9.1 4 % ,经济效益明显 。

全融合活性酵酶鲜复合蜂胶治疗难治性消化性溃疡23例

[目的]研究全融合活性酵酶(HAE)鲜复合蜂胶治疗难治性消化性溃疡(PU)的临床疗效。[方法]将44例难治性PU随机分为治疗组23例,对照组21例。治疗组给予HAE鲜复合蜂胶1粒(560 mg),3次/d,空腹口服。对照组服用奥美拉唑20 mg,2次/d,餐前口服。8周为1个疗程,治疗结束后,复查胃镜观察疗效。[结果]治疗组总有效率87.0%,与对照组比较差异有统计学意义(P<0.05)。[结论]HAE鲜复合蜂胶治疗难治性PU疗效显著。

“保酶除酵”的蜂蜜浓缩工艺技术规程在企业中的研究应用

蜂蜜作为我国有着数千年的食用历史,是天然、绿色、保健、营养的药食同源的中药材品种,掺伪造假是蜂蜜的主要质量安全问题,其活性酶代表性功能成分的保留及与发酵程度正相关的嗜渗酵母的含量可作为其重点其工艺技术研究的关键环节。文章通过前期研究基础,并根据确立的“保酶除酵”蜂蜜浓缩工艺技术规程要求,设计并总结出一条低温真空干燥浓缩蜂蜜生产线,以期为蜂蜜浓缩生产工艺提供新思路,增加国内蜂产品质量的有效性,具备其广阔的市场前景。

醇引起酵母醇脱氢酶构象变化的光谱研究

应用紫外、荧光、ＣＤ谱研究了酵母醇脱氢酶经乙醇、正丙醇和乙二醇作用后的构象变化。结果表明２２０ｎｍ、２８０ｎｍ处的紫外吸收，３３６ｎｍ的相对荧光强度随醇浓度增大而加强。ＣＤ谱显示乙醇、乙二醇引起酶分子在２０８ｎｍ、２２０ｎｍ处的双负峰逐渐加强，正丙醇使２２０ｎｍ处负峰加强，２０８ｎｍ处负峰减弱并红移，直至完全消失。上述数据表明醇浓度增加导致酶分子结构逐步松散，同时伴随着活力的丧失。

海参酶酵液对小鼠急性酒精性肝损伤的作用

目的:研究海参酶酵液(HSMJY)对小鼠急性酒精性肝损伤的作用。方法:将60只雄性昆明小鼠随机分为正常组、模型组、水飞蓟宾组(50 mg/kg)和HSMJY高、中、低剂量组(7.8 g/kg、5.2 g/kg、2.6 g/kg),每组10只。连续灌胃12 d,最后4 d通过灌胃40%乙醇溶液建立小鼠急性酒精性肝损伤模型。计算小鼠肝脏指数,测定血清及肝脏组织相关生化指标,采用苏木精—伊红(HE)染色法观察小鼠肝脏组织病理学改变。结果:与模型组比较,不同剂量HSMJY可降低急性酒精性肝损伤小鼠肝脏指数和血清AST、ALT活性以及肝脏MDA、IL-1β、IL-6和TNF-α含量(除HSMJY低剂量组小鼠血清ALT活性、肝脏TNF-α含量与模型组比较P>0.05,其余均为P<0.05或P<0.01),提高SOD活性(P<0.01),并能改善肝脏组织的病理状况,减少细胞坏死、炎症等病理状态。结论:HSMJY对小鼠急性酒精性肝损伤具有一定的保护作用,其机制可能与抑制氧化应激和炎症反应有关。

Effect of Different Raw Material Processing Methods on the Quality of Apple Distilled Spirits

In this study,the effect of yeast strains(X16 and RMS2),fruit seed,and pectinase on the quality of apple distilled spirits were investigated with apple as material.The results showed that pectinase shortened the fermentation period.The strain X16,fruit seed remaining,and pectinase addition groups had higher yields of crude distilled spirits than the strain RMS2,fruit seed removal,and without pectinase groups,respectively.Regarding the first-grade distilled spirits quality,the X16 group had higher content of total acids,total esters,higher alcohols,and alcohol content than the RMS2 group;the group with fruit seeds had higher total acids but lower alcohol content and total esters than the group with fruit seed removal;the group with pectinase addition had higher total acids and alcohol content than the group without pectinase addition.Regarding the second-grade distilled spirits quality,the X16 group had higher total acids,total esters,and alcohol content than the RMS2 group;the group without fruit seeds had higher alcohol content than the group with fruit seeds;the group with pectinase addition showcased higher total acids but lower alcohol content than the group without pectinase addition.In summary,yeast strains and pectinase affected the quality of apple distilled spirits,and strain X16 was more suitable for brewing apple distilled spirits.Pectinase affected the quality of apple distilled spirits by affecting fermentation rate and temperature.

酱油的质量

论述了酱油质量的实质及其形成的机理和条件,举例说明感官质量的重要性、强调理化质量的片面性。提出改善酱油质量应从原料和微生物2方面着手,即增加淀粉质原料的比例,采用多菌竞生,低温混合发酵的工艺。

Optimization of Fermentation Conditions of Acid Resistant α-amylase Producing Strain

[Objective] The aim was to optimize the fermentation conditions of acid resistant α-amylase producing strain. [Method] Based on the selection of an acid resistant α-amylase producing strain,the fermentation conditions including C,N contents and initial pH of culture medium,seed age,inoculum size,rotation speed of shake flask and fermentation temperature were optimized. [Result] The optimum fermentation conditions for acid resistant α-amylase producing strain were：seed age 14 h,inoculum size 8%,initial pH 5.5,fermentation temperature 35 ℃,rotation speed 150 r/min,the volume of inoculum broth 25 ml,C content 1.0% and N content 0.5%. [Conclusion] Under the optimum fermentation conditions,α-amylase activity reached 31.4 U/ml,which was 65.3 % higher than that before optimization.

Secreted Expression of S-adenosy-L-methionine Synthetase in Pichia pastoris

[Objective] The research aimed to study the secreted expression of S-edenosyl-L-methionine synthetase （SAMS） in Pichia pastoris. Method ] The gene coding SAMS, from the genomic DNA of Saccharomyces cerevisiae, was amplified by PCR and inserted into the secreted expression vector pPIC9K to get recombinant plasmid. The recombinant plasmid pPIC9K-sarr~ was integrated into Pichia pastoris GSl15 genome by electroporation and induced by methanol. The activity of the recombinant enzyme was measured using high-pedormance liquid chroma- tography （HPLC） by determining the production of S-adenosy-L-methionine （SAM） with the enzyme secreted. [ ResultJ The molecular weight of the expression protein identified by SDS-PAGE was about 50 kD, being larger than the theoretical molecular mass of SAMS, which might be due to the glycosytation in the process of secretion. Methanol-induction as well as preliminary purification could enhance the enzyme activity, espe- cially the latter, after which the specific activity of SAMS was improved to 61.48 U/rng. [Conclusion] SAMS with biological activity was secreted successfully in Pichia pastoris GSl15 for the first time. And it is the start for the genetic engineering strains to open up prospects for industrial production.

Screening of Extracellular Binding Proteins of Rice Receptor-like Kinase CR4 by the Yeast Two-hybrid

[Objective] The research aimed to find the extracellular binding proteins of CR4.[Method] The extracellular domain of OsCR4 was as the bait protein,and the yeast two-hybrid was used to screen cDNA library of seedling which was cultivated 14 d.[Result] A lot of proteins which included a peroxide B（D26484）,a methionine thioredoxin reductase（ABF96078）and an unknown function protein were gained.[Conclusion] It provided the theory basis for studying the signal transduction mechanism of CR4.

Induction and expression of T4 lysozyme gene in Pichia pastoris

Aim To induce and express the T4 lysozyme in Pichia pastoris and test the antibacterial activity of the protein. Methods T4 lysozyme gene was inserted into expression vector pPIC9K of Pichia pastoris with the fusion at N terminal. The recombinant plasmid was digested by Sal I and then introduced into prepared GS115 competent cells by electroporation. Positive clone and multiple inserts were screened. The secreted proteins in the supernatants were tested. In the agar holes diffusion assay, our expressed protein showed significant antibacterial circles. Results T4 lysozyme protein inhibited the growth of staphylococcus aureus and streptococcus Pneumoniae. There was no difference in the bactericidal activity and the amount of protein expression between the single and multiple copies. The antibacterial activity of expressed protein remained the same during the heat stability test. Conclusion T4 lysozyme was successfully induced and expressed in Pichia pastoris. There is no relationship between copy number and expression. T4 lysozyme protein is heat stable.

Expression of Exogenous Gene in Prokaryotes and Eukaryotes

[Objective] This study aimed to investigate the expression of exogenous gene in prokaryotes and eukaryotes. [Method] The expression vector pTYB2-WF harboring target gene was transformed into E. coli ER2566. IPTG was employed to induce the expression of phytase gene. The expression of phytase fusion protein was detected by SDS-PAGE, and the fusion protein was further purified. Phytase gene phyA was expressed in Pichia pastoris expression system. Yeast recombinant vector pPIC9K-phyA was constructed and transformed into P. pastoris GS115 to construct engineering strain GS115-pPIC9K-phyA. [Result] Phytase protein was ex-pressed under methanol induction. Enzyme activity assay indicated that the activity of phytase was 7.3 U/ml. P. pastoris engineering strain GS115-pPIC9K-phyA was successful y constructed. [Conclusion] Methanol yeast expression mechanisms play a certain role in molecular biology and industrial applications.

Soil Enzyme Activity Changes in Different-Aged Spruce Forests of the Eastern Qinghai-Tibetan Plateau

Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices.

Enzymatic Synthesis of Fatty Acid Methyl Esters from Crude Rice Bran Oil with Immobilized Candida sp. 99-125

The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles.

Alkaline Protease Production by a Strain of Marine Yeasts

Yeast strain 10 with high yield of protease was isolated from sediments of saltern near Qingdao, China. The protease had the highest activity at pH 9.0 and 45 ℃. The optimal medium for the maximum alkaline protease production of strain 10 was 2.5 g soluble starch and 2.0 g NaNO3 in 100 mL seawater with initial pH 6.0. The optimal cultivation conditions for the maximum protease production were temperature 24.5 ℃, aeration rate 8.0 L min -1 and agitation speed 150 r min -1. Under the optimal conditions, 623.1 U mg -1 protein of alkaline protease was reached in the culture within 30 h of fermentation.

Brewing of low-alcoholic drink from corncobs via yeast-cellulase synchronous fermentation process

The present work focuses on the influence of various parameters, i.e., the dosage of cellulase, the inoculum concentration of yeast, the fermentation temperature and the fermentation time, on the alcohol content and sensory evaluation of the low-alcoholic health drink produced from corncob in a yeast-cellulase synchronous fermentation process. The fermentation was performed by inoculating the seed solution (containing corncob powder and yeast) and cellulase into the synchronous saccharification fermentation medium. Single-factor experiments and orthogonal experiments were performed, and the optimal processing conditions were obtained based on the characterizations of alcohol content and sensory evaluation. The results show that the alcohol content and sensory evaluation of the drink can reach 6.1 vol.% and 92, respectively, when the dosage of cellulase, inoculum concentration of yeast, the fermentation temperature and the fermentation time are 15 U/g, 7%, 32℃ and 84 h, respectively.

Studies on Production of Biodiesel by Esterification of Fatty Acids by a Lipase Preparation from Candida sp. 99-125

A self-made lipase preparation from Candida sp. 99-125 was used for the production of biodiesel through enzymatic esterification of fatty acids. The crude lipase powder and fermentation broth were immobilized on a cheap fiber cloth carrier. The conditions of lipase-catalyzed esterification between long-chain fatty acids and methanol in a solvent system were investigated in detail, including the temperature, pH value, substrate concentration, solvent, absorbent agent, enzyme dosage and purity, immobilization method, the mode of addition of substrate. The results show that reaction temperature, pH of lipase micro-environment, substrate concentration, enzyme dosage and purity affect the esterification strongly. Several new methods and enzymatic procedures for improving the enzymatic reaction involving the process cost are also discussed, such as fossil diesel fuel as reaction solvent, immobilization method, multi-step gradient addition of methanol. The esterification degree of 92.8% was obtained with oleic acid and methanol under the optimal reaction condition after 12.5 h reaction time. The half-life of the immobilized lipase preparation from crude free lipase powder for esterification was 15 days.

Research on Production Conditions of Highgrade Wine from Northern Blueberry

In order to develop the best brewing condition for high-grade fruit wine from northern blueberry, on the basis of reviewing literatures about blueberry wine manufacturing process, this study put forward a new technological process, including raw materials-juicing-addition of auxiliary materials including pectinase-primary fer- mentation with yeast-post-fermentation-hot and cold treatment-sterilization-packaging- finished product, and sensory indexes, physicochemical indexes and hygienic index- es of the product were inspected according to corresponding national standards and industry standards. The results showed that for northern blueberry pulp, the optimal addition amount of yeast was 1.1 g/L, the fermentation temperature was 22 ℃, and the addition amounts of pectinase and sulfurous acid were 0.3 ml/kg and 100 ppm, respectively; the alcohol degree of the finished product was adjusted to 15.6°; and alternated cold and heat treatment used instead of conventional clarifying agent for removing colloid-like impurities resulted in the brewed product with good wine fra- grance, taste and color.