Abstract:来源于嗜热脂肪芽胞杆菌Bacillusstearothermophilus的耐热β 半乳糖苷酶基因bgaB被克隆到大肠杆菌-枯草芽胞杆菌穿梭质粒pMA5中,然后将外源基因及其表达调控序列亚克隆到枯草芽胞杆菌整合载体pSAS144中,转化Bacillussubtilis受体菌BD170,在5μg/mL的氯霉素抗性平板上筛选抗性转化子.经摇瓶发酵后,得到耐热乳糖酶的比酶活为0.32U/mg,是出发菌株比酶活的2倍.

Abstract:The properties of B-starch from wheat prepared in the laboratory, including the solubility,transparency,viscosity and gelatinization, were investigated and discussed in this paper. The differences of the properties between B-starch and A-starch are also c

Abstract:The kinetics of high ethanol fermentation by a strain of Saccharomyces cerevisae were studied in this paper. The regression models were used to describe the time-courses of substrate,product and biomass, respectively. It showed that the three state var

Abstract:The essential oils were extracted by steam distillation from the Spiced powder and the Curry powder. The antimicrobial activity of the two kinds of essential oils , including the inhibition zone,MIC value and inhibition effect of gaseous state, were com

Abstract:利用均匀设计法在有丝氨酸参与的美拉德反应条件下,对样品用5个细化的指标评分,通过多项式回归拟合该反应的回归方程,分析各因素及交互作用对反应的影响,结合回归方程和实际情况找到了最佳的反应条件为:丝氨酸2.000g,丙氨酸1.640g,半胱氨酸2.400g,木糖5.646g,水27.267g,系统pH值8.2,在120℃下反应53min。

Abstract:The immunized hemolymph was produced from Musca domestica Larvae by inducing injury. Three antibacterial peptides were purified by means of boiling water bath, dialysis and concentration, Tricine-SDS-PAGE preparation, and retrieval and renatural of pepti

Abstract:以麦芽糖、β 环糊精为原料,采用普鲁蓝酶生物反向合成得到超高水溶性的麦芽糖基(α 1→6)β 环糊精.试验测定,在pH4.0～4.2,温度58～60℃,酶量220～308U/gβ CD,麦芽糖与β 环糊精的摩尔比为7∶1～8∶1,反应时间35～38h的条件下,环糊精转化率可达到40%以上.

Abstract:以平菇、香菇为例,研究了不同含水率的食用菌经浸泡和气调包装处理后的物理、生理变化.通过实验,分别研究了不同含水率样品对其感官品质、失重率、细胞膜透性、酸度等的影响.结果表明,气调包装条件为1.5%～2.0%O2+15～20%CO2,并经浸泡液处理,含水率在87%～88.5%的平菇和含水率为85.5%～87.0%的香菇具有良好保鲜效果.

Abstract:半流质高能食品是一种特殊的食品,流变学性质是其质量评价体系中一个重要的方面,实验研究了样品在不同温度下的流变学特性.当温度一定时,半流质高能食品的粘度随剪切速率的增大而降低,具有剪切稀化现象.不同温度下的半流质高能食品的流变学模型不同:10～30℃时的流变学模型为y=mxn-1,而温度在40～50℃时的流变学模型是y=A+mln(x).比较了热处理前后样品的粘度随温度变化的规律,结果表明,热处理后的样品粘度曲线呈现平滑下降走势,而热处理前样品的粘度曲线会出现明显的波折.

Abstract:()~( 15)N-L-Proline was prepared by fermentation in a specific nutrient medium containing (()~(15)N-ammonium) chloride and growth stimulants, and with subsequent isolation and purification of ()~(15)N-L-Proline from fermentation liquid. 0.376 gram ()~(

Abstract:After separating beer foam from the several well known domestic beers, the total protein and high molecular weight protein in the liquid from the foam and the original beer were determined. The results showed that foam has the function of collecting prot

Abstract:研究了乳酸杆菌细胞壁肽聚糖的分离、鉴定及其对肽聚糖生物活性的影响.实验获得了SDS处理粗细胞壁的适宜条件为SDS质量浓度8g/dL,处理时间为沸水浴10min.SDS结合胰蛋白酶和TCA处理,可有效去除乳酸杆菌中的非共价结合蛋白质及共价结合蛋白质.经化学分析鉴定,所提取的乳酸杆菌成分为肽聚糖,肽聚糖中丙氨酸、天冬氨酸、谷氨酸和赖氨酸浓度分别为1.181,0.943,0.770和0.456mmol/g,是肽聚糖中的组分氨基酸.SDS结合TCA处理,方能较有效地去除DNA.TCA处理是去除细胞壁磷壁酸、脂磷壁酸的有效方法.此外,小白鼠腹腔巨噬细胞的吞噬实验、C3b受体实验以及血清溶菌酶活力实验证实,所分离纯化肽聚糖的免疫学活性未受影响.

Abstract:运用响应面分析法(中心组合设计)对干酪乳杆菌(Lactobacilluscasei)LB1 11生产L 乳酸的培养基C/N进行了研究,同时研究了有机氮源(蛋白胨、玉米浆和酵母膏)和无机氮源(NH4Cl和(NH4)2HPO4)对L 乳酸产量的影响,并进行了葡萄糖、蛋白胨、NH4Cl和(NH4)2HPO4四因素的响应面分析实验.结果表明,适宜的培养基C/N(质量比)为12∶1～13∶1,培养基组成:葡萄糖120.13g/L,蛋白胨19.342g/L,NH4Cl4g/L,(NH4)2HPO42.010g/L,L 乳酸产量可达到103g/L.优化后的培养基适合于对干酪乳杆菌进行代谢网络分析.

Abstract:In this paper, the Hou-Pu (Magnolia (officinalis))powder was extracted with different solvents. The antioxidative activity of each fraction extracted or isolated from Hou-Pu was tested by OSI method. The result showed that ethyl acetate is the optimal sol

Abstract:Wild Cabbage was dehydrated by a combination of hot-air drying and vacuum microwave drying. The objective was to reduce drying time and improve the products quality. It showed that total combination drying time was reduced 48.33%, and retention rate of

Abstract:低聚木糖浆中由于含有淀粉、果胶等大分子物质,易造成产品混浊.α 淀粉酶处理虽在一定程度上可减轻低聚木糖浆产品在贮藏过程中变混浊的问题,但效果仍不理想.作者采用超滤法进行澄清工艺研究,低聚木糖浆经超滤膜(相对分子质量截留为2000)处理后,大分子相对质量分数由15.35%下降至5.14%,产品贮藏3个月后也未有混浊现象出现.

Abstract:This article reported the subunit compositions of albumin and globulin from Broad beans. Two fractions of albumin and three fractions of globulin are obtained by Sepharose CL-6B gel filtration. SDS-PAGE analysis showed that broad bean globulin is comp

Abstract:The factors such as the eluate volume eluate and the size of column affecting the separation of chitosan by ion-exchange chromatography were studied. Chitosans with 80% and 90% degrees of deacetylation were separated. Three fractions were collected, freez

Abstract:建立了一种检测虾仁和牛奶中氯霉素残留的高效液相色谱(紫外检测,即LC/UV)方法和液相色谱-电喷雾电离质谱联用(LC/ESI MS)检测方法.色谱分离选用SymmetryC18柱,以乙腈-水为流动相.紫外检测波长为278nm,质谱采用选择性离子检测(M/Z321.0,[M H]-).样品制备省去传统的多次液 液萃取过程,采用有机溶剂直接提取,转溶后,用固相萃取方法净化样品.虾仁和牛奶样品的平均回收率分别为93.7%和96.0%;检测限:LC/UV为2.5μg/kg和8.3μg/kg;LC/ESI MS为1.3μg/kg和4.5μg/kg.方法准确灵敏,样品预处理较简便快速.

Abstract:In this paper,the extracting methods and conditions of hemicellulose from corncob were improved,the ratio and purity of extraction were effectively raised by integration of cooking with alkalitreatment.The extracted hemicellulose were used as selective ca

Abstract:The aim of this paper is to study active constituents in corn silk and to investigate the possibility of using those active compositions to cure desease.The organic acids in corn silk were analyzed by GC-MS. Experiment results showed that the organic aci

Abstract:A method of fresh keeping of Water Chestnut at room temperature was introduced and compared with the others. This method is of characterics of convenience,economization and high efficiency. The results showed that the Water Chestnut preservation method c

Abstract:The compositions of amino acid,water,ash,crude protein, fat,fibre,mineral components and P.umbellatus polysacchride in the wild and cultivated P.umbellatus collected in Mt. Qinling and Mt. Bashan regions were determined. The result showed tha

Abstract:Red pigment was extracted by means of hydrochloric acid-alchohol solution, and the pigment was purified by use of ether. Based on the changes of red pigment solution under the different pH value and absorption bands,as well as the effect of different me

Abstract:The definition and technological characteristics of combination drying were formulated in this work. Meanwhile, this study introduced current research and application of various combination drying methods both inland and outland. Finally, the existing pro