Abstract:Water soluble pentosan was prepared from wheat bran using water. The prepared pentosan was a mixture, it was fractioned by stepwise ethanol precipitation, ion exchange chromatograph and gel filtration chromatograph, respectively. Two main purified fracti

Abstract:初步探讨了一种微生物转化生产d 伪麻黄碱的新方法.通过TLC和HPLC分析,对实验室保藏菌株进行筛选,得到可专一性转化前体物质1 苯基 2 甲氨基丙酮(1 phenyl 2 methylamino propanone,简称MAK)生成d 伪麻黄碱的菌株MorganellamorganiiJ 8.通过对转化条件的研究,发现最适起始转化pH为7.5,最适转化温度为40℃.在合适的转化条件下,经过24h能将1000mg/L的MAK转化为852.4mg/L的d 伪麻黄碱,相应的摩尔转化率为84.4%.

Abstract:对重组人血管抑素表达菌株pQE32 AGN的生长及产物表达规律进行了探索,确定了最佳发酵条件.培养温度为37℃,初始pH7.0,OD600为0.8～1.0时开始诱导,诱导持续时间为6h,诱导剂浓度为0.1mmol/L,最终目的产物达到菌体总蛋白的35%,rhAGN的表达量达到560mg/L.

Abstract:采用中性蛋白酶处理热凝胶胞外多糖发酵液,降解其中的菌体,实验证明,与传统的酸碱法相比,中性蛋白酶法更能有效地对热凝胶多糖发酵液提纯,而且保持了其主要性能--热成胶性.进一步确定了酶法提取纯化热凝胶的最优条件,获得的多糖产品为纯一的β-(1,3)葡聚糖,且有效地去除了蛋白质等杂质.

Abstract:二氢杨梅素是一种重要的黄酮类物质,具有较好的抗氧化活性.通过溶析称重法测定了溶解度的变化,采用紫外 可见光谱扫描法研究其化学结构的变化,结果表明:二氢杨梅素溶液易发生氧化,稳定性较差,在不超过100℃,加热时间不超过30min以及酸性和中性条件可保持其化学结构稳定,而过渡态金属离子Al3+,Fe3+,Cu2+等对二氢杨梅素的氧化则起到诱导催化作用.

Abstract:Gelling properties of soy protein-gum mixtures were determined by small deformation oscillation and the experimental data were analyzed with blending laws of polymers. Gel strength of soy protein-carrageenan mixture was found to follow either upper or low

Abstract:甘油脱水酶是1,3 丙二醇发酵过程中的重要限速酶,具有很好的工业应用前景.其中α亚基为甘油脱水酶的主要组成部分,该基因的正确克隆与分析对甘油脱水酶的正确表达起重要作用.作者采用PCR技术,从肺炎克雷伯氏杆菌A.S.1.1736基因组中扩增得到了编码甘油脱水酶α亚基的gldA基因,并将其克隆至pMD18 T载体中.经核苷酸序列分析证实,gldA基因开放阅读框架由1668bp组成.经GenBank检索对照分析,gldA基因序列与国外文献报道的同源性达99.34%,表明所克隆的gldA基因即为克雷伯氏甘油脱水酶α亚基基因.

Abstract:Lipases from different commercial sources were screened in terms of their regioselectivities (RE) and activity of esterification. Obvious differences were found in the RE value so that it can be selected as a measure to classify these biocatalysts as tho

Abstract:A strain, Lactobacillus plantarum RS2-2, with intracellular L-LDH activity was isolated from pickled vegetable juice. After mutating it by nitrosoguanidine combining with ultrasonic, the specific activity was increased from 3.48 U/mg to 7.49 U/mg. The fer

Abstract:实验研究了不同热处理条件对保持蒲菜绿色的效果,结果表明:当热处理条件为120℃加热10min,热处理溶液pH值为7.0;十二烷基硫酸钠质量浓度为1g/L;Zn2+质量浓度为100mg/L;料液体积比为1∶3;锌盐为ZnCl2时,蒲菜表皮色泽的-a值达7,在贮藏中能很好地保持绿色.

Abstract:The capacity and speed of yeast to assimilate monosaccharide is bigger than that of yeast to assimilate of oligosaccharide, so the redundant glucose in ismalto-oligosaccharide products can be consumed.A strain D was isolated and screened, which could fast

Abstract:To prepare Oyster Functional Oligopeptides (OFO) with ACE activity inhibition capability, The fresh oysters without shells was hydrolysed by a microbial protease alcalase. The OFO were separated from the hydrolyzate by Sephadex G-15, their molecular weigh

Abstract:The synthesizing conditions of ferrous glycinate chelate using ferrous chloride and glycine as raw materials were studied in this paper. The result showed that the constitution of the product and the recovery of ferrous were considerably affected by pH, t

Abstract:The extensive use of antibiotics has resulted in an increase of antibiotic resistant strains of bacteria. Alternative methods such as photodynamic therapy are necessary for the inhibition of bacteria. In the present study, the chlorophyllin ester was foun

Abstract:分别采用紫外分光光度法和肼比色法检测了人工圈养秦岭大熊猫的2种主食竹叶———淡竹和箬竹中还原型维生素C和总维生素C的含量.结果显示,全株总维生素C含量在2种竹叶中无明显差别,但还原型与总维生素C的比例有所不同,箬竹、1年生淡竹和2年生淡竹竹叶中还原型维生素C分别是总维生素C质量分数的39.7%、32.5%和28.1%.不同部位淡竹竹叶中2种类型维生素C含量有相似的趋势,即上部竹叶维生素C水平明显高于下部(1.26～2.07倍),而且随着竹龄增长维生素C的水平有不同程度降低.

Abstract:分析了葡醛内酯传统工艺中淀粉原料、中间产物及产品流失的主要原因,提出了从葡醛内酯生产废液中通过二次内酯化进一步回收产品的可行性方案.结果表明,在V(硝酸)∶V(冰醋酸)∶V(废液)=0.6∶1.0∶10,反应温度为60℃,反应时间为60min的条件下,葡醛内酯提取物每100mL废液可达6g,纯度为82%.

Abstract:油豆腐是一种营养丰富的豆制品,由于含有较高的蛋白质和脂肪,其产品不易保存.将油豆腐制成软罐头的形式,既能延长其保质期,又便于食用.试验用高温高压杀菌锅对油豆腐软罐头进行杀菌研究,确定其最佳杀菌工艺为120℃条件下9min-25min-10min.在该杀菌工艺条件,油豆腐中微生物指标达到软罐头产品质量标准,油豆腐软罐头能保存半年以上时间.

Abstract:Thiosulfinates are the best known biological active compound in garlic. It is produced by the interaction of nonprotein amino acid alliin with enzyme alliinase (alliin lyase, EC 4.4.1.4). In this paper, thiosulfinates were extracted by solvent under mild

Abstract:Original strain Corynebacterium acetoacidophilum ATCC13870 was mutated by NET, DES and ~(60)Co. As a result of a strain named G21-8,producing Glutamine was obtained. Under optimum condition , G21-8 was able to accumulate an average of 32.5 g/L, and the h

Abstract:Fucoidan, separated from Sargassum fusiform (grown in Dongtou, Zhejiang Province), was graded into three fractions: F1, F2 and F3 by chromatography on a DEAE Sepharose CL-6B column. F3 was further graded into three fractions: F31, F32 and F33 by chromatog

Abstract:A gas chromatography/mass spectrometry method was developed for the identification of 6 alkoxyglycerols components in shark oil (ocean near Tasmania of Australia). The sample was saponified with potassium hydroxide in aqueous methanol and non-saponifiable

Abstract:在玉米芯木聚糖的碱法提取中,玉米芯木聚糖在80℃抽提120min的抽提率较高,还原糖质量分数较低,同时,抽提液的颜色较浅,明显优于121℃抽提30min.以80℃抽提的木聚糖为诱导,草菇产生的木聚糖酶的酶活比121℃抽提的木聚糖的酶活高.以80℃抽提的木聚糖为碳源,通过正交试验,设计出适合草菇生长和产生木聚糖酶的发酵条件.培养基组成为:木聚糖15g/L,(NH4)2SO42.5g/L,Tween 803g/L,酵母膏1g/L,KH2PO41g/L,MgSO4·7H2O0.6g/L,微量元素0.0005g/L.pH7.0,40℃下150r/min培养4d,此时酶活达32.4IU/mL.

Abstract:比较苦参的灵芝发酵液和苦参与灵芝发酵液的混合液体外抗乙肝病毒(HBV)的效果.用HBVDNA转染的2.2.15细胞作为模型,放射免疫法测定2种药物作用后细胞培养上清液中HB sAg和HBeAg量,计算其对HBsAg和HBeAg分泌的抑制率,用MTT法检测细胞毒性.结果表明:剂量在12.5～200μg/mL的范围内,均能不同程度地减少细胞培养上清液中的HBsAg和HBeAg量,发酵液细胞的毒作用不明显,而混合液具有一定的细胞毒作用.结果显示发酵液具有一定的体外抗HBV作用.

Abstract:通过对点样量、展开体系、显色方法等研究,解决了利用纸层析法定量测定γ 氨基丁酸误差大、重现性差的问题,从而建立了以纸层析法定量测定γ 氨基丁酸的方法.结果表明,此法定量测定γ 氨基丁酸简单易行,耗费低廉,可作为食品中γ 氨基丁酸分析测定的手段.

Abstract:Fractal theory that studies irregular, non-smooth geometrical figures produced in nonlinear system has been applied to food science. Fractal theory makes good explanation for many nonlinear problems in the fields of large biological molecules, such as DNA