稀碱法提取食用蝇蛆蛋白

对蝇蛆粉充分脱脂后采用稀碱法提取蝇蛆蛋白。结果表明,液料比、浸提温度、碱浓度对提取得率有显著影响(P<0.01),提取时间对提取得率影响差异不显著。蛋白提取的最佳条件为:液料比20mL/g,浸提温度80℃,浸提时间2h,碱浓度1%(w/v)。在此条件下,所得蝇蛆蛋白粉蛋白氮含量为11.14%,蛋白得率为57.53%,提取效率为69.84%。对最优条件下得到的蝇蛆蛋白粉进行理化指标检测,并与速溶豆粉的企业标准以及脱脂乳粉的国家标准进行比较。结果表明,水分、灰分、脂肪、蛋白含量均已达到可食用级别的要求,重金属铅、汞、砷含量均低于限量要求,微生物检测不含致病菌和大肠杆菌,在最优提取条件下所得蝇蛆蛋白粉,综合指标已达可食用标准。     

茶多酚提取优化工艺研究

本文研究了可食用茶多酚的提取优化工艺。萃取剂为乙醇,料液比1：15,浸提过程伴随300W超声波震荡,就乙醇的浓度、提取温度、提取时间和提取次数等因素利用正交设计筛选了茶多酚的最佳提取工艺条件,并对浸提液最佳离子沉淀方法作了比较。结果表明,茶多酚提取的最佳工艺条件为：65％的乙醇溶液作浸提剂,当浸提温度为50℃,浸提时间30min,两次超声波辐射浸提后茶多酚从粗茶叶中的提取率为20．1％。沉淀剂AlCl3和ZnSO4质量比为1：2对茶多酚的沉淀效果最佳,pH=6．0。     

加压提取地榆根中黄酮成分的研究

研究加压提取地榆中黄酮的最佳提取工艺。探讨了乙醇浓度、料液比、粒径、提取压力、提取温度和提取时间6个因素对黄酮得率的影响,并通过正交试验优化,确定了加压提取地榆中黄酮的最佳条件。结果表明加压提取地榆中黄酮的最佳提取条件:浸提温度120℃,料液比为1∶20,提取溶剂为60%的乙醇,浸提时间为30min,浸提压力为5 kg/cm2,粒径为40目,在该条件下黄酮提取率可达17.35%。与回流提取法相比,加压浸提法可显著提高浸提率。     

纤维素酶提取楮实子多酚及其抗氧化性研究

以楮实子为原料,采用纤维素酶法研究楮实子多酚的提取工艺,以单因素实验(纤维素酶含量、浸提时间、液料比、浸提温度和p H)为依据,选取浸提时间、液料比、浸提温度和pH等4因素,以楮实子多酚提取率为指标,通过4因素3水平的Box-Behnken实验设计,优化了楮实子多酚提取的工艺参数,结果表明:浸提时间150 min、液料比35∶1 mL/g、浸提温度70℃、pH6.10,楮实子多酚提取率达到39.67 mg/g。并通过2种体外抗氧化实验(DPPH自由基清除力和铁氰化钾还原法),证明楮实子多酚具有较强的抗氧化活性。     

芦笋茎叶游离氨基酸的提取及含量测定

通过对芦笋茎叶游离氨基酸提取工艺中温度、提取时间、料液比、乙酸浓度等影响因素的试验分析,确定芦笋茎叶游离氨基酸测定过程中的最佳提取条件为：提取温度60℃;料液比为1：35;提取时间为2．5h;并对芦笋茎叶游离氨基酸含量进行了测定,确定芦笋茎叶游离氨基酸含量为76．54mg／100g。     

杜梨叶黄酮的提取工艺研究及其初步定性分析

目的:优化杜梨叶总黄酮提取的工艺及其初步定性分析.方法:研究了浸提温度、乙醇浓度、提取时间、料液比等因素对杜梨叶中黄酮类化合物提取效果的影响,和正交试验进行优化,所得结果采用方差分析.采用颜色反应的方法进行杜梨叶中黄酮的初步定性分析.结果:确定了最佳单因素水平,正交实验确定了以乙醇为浸提荆的最佳提取工艺条件为:乙醇体积分数60%,料液比1:22,温度80℃,浸提时间1h,在此条件下黄酮含量为5.03%.结论:杜梨叶中含黄酮类化合物,颜色反应试验表明,其成分主要集中在黄酮醇类和二氢黄酮类.     

正交试验法优选三七茎叶中总黄酮的提取工艺

目的：从三七茎叶中提取总黄酮。方法：采用正交试验法研究三七茎叶总黄酮的提取工艺,考察了浸提用水的pH值、浸提温度、浸提时间、浸提次数、液料比五个因素对三七茎叶总黄酮提取率的影响。结果：确立了三七茎叶总黄酮最佳提取条件为：用pH10的稀碱水作溶剂,液料比30：1,浸提温度为80℃,回流提取2次,提取时间为每次40min。     

超声波辅助浸提毛木耳总黄酮类化合物的工艺优化

黄酮类化合物是一类重要的次生代谢产物,广泛存在于各种植物和真菌中,具有抗菌、抗癌、抗氧化等生物活性。本研究以提取毛木耳子实体中总黄酮量为考察指标,运用响应面分析法研究了超声功率、浸提时间、乙醇浓度和料液比4个因素对总黄酮提取量的影响,以获得提取毛木耳总黄酮的最优工艺。经响应面分析,各因素按照对响应值的影响顺序为：浸提时间＞超声功率＞乙醇浓度＞料液比,且超声功率、浸提时间、乙醇浓度对总黄酮提取量的影响极显著。结果表明提取毛木耳子实体中总黄酮含量的最优工艺为：超声功率168W、浸提时间50min、乙醇浓度60%、料液比1:7,总黄酮的最大预测提取量为2.11%。验证试验结果表明,总黄酮含量平均为2.08%,与理论值基本吻合。本研究将为食用菌中总黄酮的提取工艺提供理论基础。     

水皂角多酚的提取工艺研究

本研究通过单因素实验和正交实验 ,以提取物中水皂角总多酚含量为考察指标 ,对影响水皂角多酚提取效果的各因素进行了研究。结果表明各因素对水皂角多酚提取效果的影响程度从高到低依次为 :浸提温度 >乙醇浓度 >固液比 >浸提时间。确定了水皂角多酚的最佳提取工艺为乙醇浓度 70 % ,浸提温度 70℃ ,浸提时间 5h ,固液比 1∶10。     

正交设计优选橙皮苷提取工艺研究

采用碱-醇提酸沉法提取陈皮中橙皮苷,首先针对提取温度、提取时间、pH值、碱液料液比、醇液料液比、提取次数等因素对提取率的影响进行单因素实验考察,并进一步利用正交实验对橙皮苷的提取工艺进行优化。得到最优浸提条件为:陈皮粉与食用乙醇料液比为1:10、与0.5%NaOH溶液料液比1:10,浸提温度70℃,浸提时间4 h,提取率最高。     

Synergistic Enhancement of the Antifungal Activity of Wheat and Barley Thionins by Radish and Oilseed Rape 2S Albumins and by Barley Trypsin Inhibitors

Although thionins and 2S albumins are generally considered as storage proteins, both classes of seed proteins are known to inhibit the growth of pathogenic fungi. We have now found that the wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.) thionin concentration required for 50% inhibition of fungal growth is lowered 2- to 73-fold when combined with 2S albumins (at sub- or noninhibitory concentrations) from radish (Raphanus sativus L.) or oilseed rape (Brassica napus L.). Furthermore, the thionin antifungal activity is synergistically enhanced (2- to 33-fold) by either the small subunit or the large subunit of the radish 2S albumins. Three other 2S albumin-like proteins, the barley trypsin inhibitor and two barley Bowman-Birk-type trypsin inhibitor isoforms, also act synergistically with the thionins (2- to 55-fold). The synergistic activity of thionins combined with 2S albumins is restricted to filamentous fungi and to some Gram-positive bacteria, whereas Gram-negative bacteria, yeast, cultured human cells, and erythrocytes do not show an increased sensitivity to thionin/albumin combinations (relative to the sensitivity to the thionins alone). Scanning electron microscopy and measurement of K+ leakage from fungal hyphae revealed that 2S albumins have the same mode of action as thionins, namely the permeabilization of the hyphal plasmalemma. Moreover, 2S albumins and thionins act synergistically in their ability to permeabilize fungal membranes.     

Albumin storage proteins in the protein bodies of castor bean

Of the total protein in the protein bodies of castor bean (Ricinus communis L.), approximately 40% is represented by a group of closely related albumins localized in the matrix of the organelle. This group of albumins has a sedimentation value of 2S and is resolved into several proteins of molecular weight around 12,000 daltons by sodium dodecyl sulfate-acrylamide gel electrophoresis. It has a high content of glutamate/glutamine and undergoes rapid degradation during the early stage of germination. In view of the abundance and ubiquitous occurrence of albumins in various seeds, we suggest that albumins, in addition to globulins, glutelins, and prolamines, are important storage proteins in seeds.     

大麦籽粒及花药愈伤组织的游离氨基酸含量分析

对同一基因型大麦花药愈伤组织与籽粒中的游离氨基酸含量尤其是赖氨酸含量之间的关系进行分析,结果表明,对同一基因型而言,愈伤组织及籽粒中的同一氨基酸含量高低具有相同趋势。同时着重分析了愈伤组织中游离脯氨酸的含量与绿苗分化的关系,结果表明游离脯氨酸含量高的愈伤组织,其绿苗分化率较高,说明脯氨酸对绿苗分化具有重要作用。966259的花药愈伤组织及籽粒中的游离氨基酸总含量及游离赖氨酸含量均最高。     

A cathepsin F-like peptidase involved in barley grain protein mobilization, HvPap-1, is modulated by its own propeptide and by cystatins

Among the C1A cysteine proteases, the plant cathepsin F-like group has been poorly studied. This paper describes the molecular and functional characterization of the HvPap-1 cathepsin F-like protein from barley. This peptidase is N-glycosylated and has to be processed to become active by its own propeptide being an important modulator of the peptidase activity. The expression pattern of its mRNA and protein suggest that it is involved in different proteolytic processes in the barley plant. HvPap-1 peptidase has been purified in Escherichia coli and the recombinant protein is able to degrade different substrates, including barley grain proteins (hordeins, albumins, and globulins) stored in the barley endosperm. It has been localized in protein bodies and vesicles of the embryo and it is induced in aleurones by gibberellin treatment. These three features support the implication of HvPap-1 in storage protein mobilization during grain germination. In addition, a complex regulation exerted by the barley cystatins, which are cysteine protease inhibitors, and by its own propeptide, is also described.     

转trxS基因大麦发芽种子水解酶活性的变化

利用转基因技术是改良大麦品种品质的有效途径.研究了转trxS基因对大麦种子发芽过程中水解酶活性的影响,结果表明转基因种子中α-淀粉酶、自由态β-淀粉酶和极限糊精酶的活性比未转基因种子高;转基因种子醇溶蛋白和谷蛋白中巯基的含量提高,说明该基因能够表达,为大麦育种和品质改良提供新的途径.     

Endogenous Elicitor Present in Barley Seeds

Endogenous elicitor(s) present in barley seeds induce the accumulation of antifungal substances effective against powdery mildew fungi. Antifungal substances induced by the treatment with barley seeds extract coincides with the one induced by the inoculation with compatible or incompatible races of powdery mildew fungi on thin-layer chromatography analysis. The resistance induced by the treatment with barley seeds extract correlates to the accumulation of the antifungal substances in barley leaves. Furthermore, the activity of phenylalanine ammonia-lyase was also induced by the treatment with barley seeds extract.     

Characterization of Albumins fromLupinus luteus L. Cotyledons

The cotyledons of yellow lupin seeds contain 15.4 mg of the albumins, water soluble proteins, per 100 mg of dry matter. These proteins were resolved by SDS gel electrophoresis into 13 polypeptides with relative molecular mass, Mr, between 16 000 and 84 000. Isoelectrofocusing analyses of the albumins showed that they were composed of six components with isoelectric points between 4.1 and 5.5. These results have indicated that the albumins are acid proteins and exhibited molecular and charge heterogeneity.     

Reserve Mobilization During Germination of Tagetes minuta L.

Levels of albumins, globulins and starch were measured in dryTagetes minuta L. achenes (seeds) germinating at 25 °C andin those thermo-inhibited at 35 °C. In addition, the compositionof amino acids, fatty acids and free sugars was determined. In germinating seeds, albumins increased, while globulins decreased.At 35 °C, only a delayed decrease in globulins occurred.However, in both, the amino acids serine and glutamate increased.Lipid composition remained constant except for a slight declinein linoleic acid in the germinating seeds. At 25 °C, starchlevels increased with time while at 35 °C, there was onlya transient increase. Sucrose was the major free sugar foundin the seeds at all times, but its levels declined in the germinatingseeds. This was accompanied by an increase in the proportionsof glucose and fructose. No such changes in sugar compositionwere observed in the thermo-inhibited seeds. Tagetes minuta L., seed germination, reserve mobilization, thermo-inhibition     

A STATIC MAGNETIC FIELD OF 125 mT STIMULATES THE INITIAL GROWTH STAGES OF BARLEY (Hordeum vulgare L.)

In this paper the influence of a stationary magnetic field on the initial stages of barley plant development was evaluated. A stationary magnetic field has a stimulating effect on the first stages of growth of barley seeds for all exposure times studied. When germinating barley seeds were subjected to a magnetic field of 125 mT for different times (1, 10, 20, and 60 min, 24 h, and chronic exposure), increases in length and weight were observed. Maximum increases in the measured parameters were obtained when the time of exposure to magnetic field was long (24 h and chronic); however, the exposure for a short time (1 min) had a similar effect on growth.     

Repair of single-strand DNA breaks and recovery of chromosomal and chromatid aberrations after treatment of plant seeds with propyl methanesulfonate in vivo.

Repair of single-strand breaks of DNA and simultaneous recovery of chromosomal aberrations were studied after treatment of barley seeds with the monofunctional alkylating chemical mutagen, propyl methanesulfonate in vivo. In soaked seeds the diminution of single-strand breaks of DNA induced by PMS was correlated with the decrease of chromosomal aberrations, whereas in dried seeds the repair of DNA breaks was depressed and, in accord with this, the frequency of chromosomal aberrations increased. The prolonged storage of seeds led to a more delayed repair of chromosomal aberrations in dry seeds and a more delayed accelerated repair in soaked seeds.