金银花精油及其与β-环糊精包合物的制备工艺研究

[目的]优选金银花精油及其与β-环糊精包合物的制备工艺。[方法]采用水蒸气蒸馏法制备金银花精油,用GC-MS分析金银花精油的主体呈香成分及含量;采用饱和水溶液法,通过正交试验设计,以金银花精油的包合率为指标,考察金银花精油与β-环糊精的包合比例、包合温度、搅拌时间和烘干温度对金银花精油-β-环糊精包合物制备工艺的影响。[结果]水蒸气蒸馏法制备金银花精油的得率为0.12%,经GC-MS分析,金银花精油的主体呈香成分为单萜和倍半萜类化合物,占金银花精油含量的75.30%,其中,金银花精油中芳樟醇及其衍生物含量大于25.60%;最佳金银花精油-β-环糊精包合物制备工艺条件为金银花精油与β-环糊精的包合比例1∶10(m L∶g)、包合温度60℃、搅拌时间3 h、烘干温度45℃,在此最优条件下,金银花精油的包合率为68.95%。[结论]水蒸气蒸馏法和饱和水溶液法可分别用于金银花精油及其与β-环糊精包合物的制备。     

中药组方“回乳康”对回乳期奶牛血清E、P4和TGF-β1含量的影响

【目的】探究中药组方"回乳康"对回乳期奶牛血清雌激素(Estrogen,E)、孕酮(Progesterone,P4)和转化生长因子β1(Transforming growth factorβ1,TGF-β1)含量的影响。【方法】选取即将干乳日产奶量为(15.42±0.71)kg的健康奶牛80头,随机分为4组,每天饲喂0(对照组)、400、500和600 g"回乳康"中药,采用逐渐干奶法回乳,分别在回乳第0、1、3、5、7、9和11天采集奶牛尾静脉血,并记录奶牛单日产奶量,采用ELISA法检测血清E、P4和TGF-β1含量。【结果】0、400、500和600 g处理回乳时间分别为11、7、5和5 d;各组奶牛血清E含量在回乳期均随时间推移呈下降趋势,对照组下降趋势较中药组慢;对照组奶牛血清P4含量在回乳期变化不显著,而中药组奶牛血清P4含量均随时间推移呈上升趋势,在回乳期之后下降,但下降后仍极显著高于对照组;各处理回乳期奶牛血清TGF-β1含量均呈上升趋势,而在回乳期之后中药组奶牛血清TGF-β1含量呈下降趋势;回乳期奶牛血清E、TGF-β1含量和日产奶量两两间均呈极显著相关,血清P4含量与血清E、TGF-β1含量、日产奶量均无显著相关性。【结论】在奶牛回乳过程中,添加中药组方"回乳康"能显著促进回乳期奶牛回乳,E是奶牛回乳的负调控激素,TGF-β1是正调控因子,而P4对回乳无明显影响。     

刺激隐核虫感染诱导斜带石斑鱼MHC Ⅰα和β2m基因的表达谱分析

[目的]检验石斑鱼(Epinephelus coioides)MHC Ⅰα和β2m基因是否参与诱导抗寄生虫免疫应答,为揭示鱼类免疫系统启动抗刺激隐核虫(Cryptocaryon irritans)感染的细胞免疫应答分子机制打下基础.[方法]以实时荧光定量PCR对刺激隐核虫感染斜带石斑鱼前后MHCⅠα和β2m基因在感染局部位点和免疫器官中的表达变化进行检测.[结果]MHCⅠα和β2m基因在健康斜带石斑鱼的组织中均呈组成性表达,且以在外周血、腮、头肾和脾脏中的表达量较高.经刺激隐核虫感染后,MHCⅠα和β2m基因在斜带石斑鱼皮肤中的表达明显上调,均在感染后第5 d达峰值,其中MHCⅠα基因的最大表达量为2.6倍、β2m基因的最大表达量为6.1倍;在腮中二者呈波动性变化,而在头肾中以显著下调为主.在脾脏中,MHCⅠα基因在刺激隐核虫感染后第5 d显著上调表达,为对照组的2.0倍,至感染后第7 d其表达水平略微下调,为对照组的1.5倍;β2m基因表达于感染后12h即升高至对照组的4.0倍,此后呈下调表达趋势,至感染后第5 d其表达水平再次上调为对照组的3.4倍.[结论]在刺激隐核虫感染过程中,斜带石斑鱼MHCⅠα和β2m基因的相对表达量在皮肤、鳃、头肾和脾脏中均发生了明显变化,即鱼类MHC Ⅰ类分子可能参与了机体的细胞免疫,在抗寄生虫感染的特异性免疫应答过程中发挥重要作用.     

An ABAGE-Like Metabolite of Botrytis cinerea Isolate BC4 Inhibited the Growth of Hypocotyls and Roots of Amaranthus retroflexus Seedlings

A metabolite, which had an inhibitory effect on plant growth, was isolated from cultural filtrate of Botrytis cinerea isolate BC4 by column chromatography on silica gel and preparative HPLC. Its structure was determined from HPLC-ESI MS, GC, IR, ^1H NMR and ^13C NMR spectral data, as well as chemical hydrolysis. The results showed that this metabolite was quite similar to abscisic acid-β-D-glucopyranosyl ester（ABAGE） in structure. The inhibitory effect of the ABAGE-like metabolite on plant growth was investigated using a weed Amaranthus retroflexus L. as a bioassay material. The results showed that it inhibited hypocotyls and roots growth of A. retroflexus （Amaranthus retroflexus L.） seedlings when its concentration was over 0.5 μM. The concentrations for 50% inhibition of hypocotyls and roots growth of A. retroflexus seedlings were 2.8 and 1.4 μM, respectively.     

不同β-胡萝卜素供给水平对奶牛血液和乳中胡萝卜素含量的影响

通过在奶牛日粮中添加β-胡萝卜素制剂,用高效液相色谱测定奶牛血液和乳中的β-胡萝卜素含量,研究不同β-胡萝卜素制剂添加水平对奶牛血液和乳中胡萝卜素含量的影响.试验结果表明,在添加β-胡萝卜素第60 d,奶牛血液中胡萝卜素的含量变化为:基础日粮+300 mg/dβ-胡萝卜素添加组(Ⅱ)比基础日粮对照组(Ⅰ)增加了38.55%,差异显著(P<0.05);基础日粮+600 mg/dβ-胡萝卜素添加组(Ⅲ)比对照组Ⅰ增加了99.24%,差异极显著(P<0.01);基础日粮+900 mg/dβ-胡萝卜素添加组(Ⅳ)比对照组增加了122.85%,差异极显著(P<0.01).Ⅱ、Ⅲ、Ⅳ组奶牛牛乳中β-胡萝卜素的含量在添加胡萝卜素第60 d,分别比对照组(Ⅰ)增加了63.27%、148.46%、262.29%,差异均极显著(P<0.01).     

青霉QM-1产酸性β-甘露聚糖酶液体发酵条件研究

[目的]为酸性β-甘露聚糖酶生产菌株的开发与应用提供技术参考。[方法]以单因子试验和正交试验对青霉QM-1（Penicillium sp．）液体发酵产酸性β-甘露聚糖酶条件进行研究。[结果]产酶最适培养基配方：麸皮＋魔芋粉（2：1）10．0g／L,NaNO3 2．0s／L,KH2PO4 1．5g/L,MgSO4·7H2O 0．3g／L,H2O 1000ml。最适培养条件为：起始pH值6．0,装液量为50ml／250ml三角瓶,转速为175r／min,在35℃下培养4d,最高酶活力达86．3IU。该菌所产粗酶液最适反应温度为60℃。[结论]麸皮和硝态氯能有效促进青霉QM—1产酸性β-甘露聚糖酶,且所产的β-甘露聚糖酶有一定的温度耐受性。     

β–1,3葡聚糖酶基因转化提高苹果对斑点落叶病的抗性

为提高苹果抗病性,利用根癌农杆菌介导的叶片转化法,将带有NPTⅡ筛选基因、GUS标记基因及β–1,3葡聚糖酶目的基因质粒导入‘富士’和‘嘎拉’苹果。具有卡那霉素(Kan)抗性的转化株系,经GUS组织化学染色及PCR扩增检测,得到17个‘嘎拉’阳性株系和11个‘富士’阳性株系。选取‘嘎拉’和‘富士’各3个阳性株系进行Southern blot检测,结果表明外源目的基因已整合到所试转化株系中。选取‘嘎拉’及‘富士’各5个阳性株系进行半定量RT-PCR检测,除1个‘富士’株系没有条带外,其余株系均有阳性条带,且各条带的明亮清晰程度有差别,说明不同转基因株系中目的基因的表达量有差异。转化植株离体叶片接种苹果斑点落叶病菌进行抗病性表型检测结果证实,‘嘎拉’10个转化株系中8个株系表现抗病,7个‘富士’转化株系中2个株系表现一定的抗病性,抗病性的增强与目的基因的表达水平有关。     

斑玉蕈β-葡萄糖苷酶基因的序列分析及皂苷对基因表达的影响

通过转录组测序获得了斑玉蕈(Hypsizygus marmoreus)SIEF3133菌株的β-葡萄糖苷酶基因的cDNA序列(命名为bgl1),采用荧光定量PCR检测bgl1的相对表达量。当PDB中加入0.05g/L的皂苷溶液,菌丝培养4~6d时,bgl1相对表达量降低了1/2左右(相比对照),8d开始升高,第10天为对照组的1.8倍;向工厂化生产用的栽培瓶(接种培养85d后搔菌处理)中添加0.05g/L的皂苷溶液15mL,可缩短子实体采收时间约3d(与对照组相比),在此过程中bgl1相对表达量在第5天时最低,20d时超过对照组,5d时为对照组的1.66倍。     

Development,and genetic and metabolic characterization of new tomato mutants with enhanced and deficient carotenoid content

Tomato (Solanum lycopersicum) is a valuable vegetable crop rich in health-protective carotenoids, but breeding improvements are limited by its narrow genetic diversity. New mutants with enhanced and deficient carotenoid content in a single genetic background of tomato cv. MicroTom were developed via chemical mutagenesis. Genetic and metabolic analyses showed that mutant DC260, which exhibited fruit color alteration from red to deep red interlaced with orange color, had significant (P < 0.05) increases of lycopene (up to 42.8%) and ß-carotene (up to 61.5%) compared with control plants. Pearson correlation analysis of M1 and M2 generations in DC260 revealed that fruit color alteration was significantly (P < 0.05) correlated with lycopene (coefficient = 0.55) and ß-carotene content (coefficient = 0.63). The fruit color alteration of DC260 was controlled by a single gene at a heterozygous locus. In contrast, mutant DC107 and DC624, which exhibited fruit color alteration from red to orange-yellow, was significantly (P < 0.05) carotenoid-deficient with up to 346.3-, 10.8-, and 185.2- fold reductions of lycopene, ß-carotene, and total carotenoids, respectively, compared with the control plants. Carotenoid deficiency in DC170 and DC624 was responsible for the fruit color alteration and was controlled by a dominant gene at a homozygous locus.     

Extraction and purification of an endo-1,4-β-xylanase from wheat malt

Wheat and wheat malt are known to be high quality raw materials in the beer brewing process. The size and structure of wheat arabinoxylans (AXs) and their enzymatic degradation products have a profound impact on beer properties, such as viscosity, turbidity, filtration rate and foaming properties. AXs are of great benefit to human health due to their anti-tumor properties and potential roles in the immune system. Endo-1,4-β-xylanase is a key enzyme for degradation of AXs and production of small molecule AXs, thereby altering the properties of AXs, such as solubility, viscosity, and turbidity. In this study, extraction and purification of an endo-1,4-β-xylanase from wheat malt was described. The results showed that, after 40%–60% ammonium sulfate precipitation, Q-Sepharose Fast Flow anion exchange chromatography, Phenyl-Sepharose 6 Fast Flow Hydrophobic chromatography, and twice sephacryl S-100 HR gel filtration, a final endo-1,4-β-xylanase was obtained. The purified wheat malt endo-1,4-β-xylanase showed a single band on SDS-PAGE with a molecular weight of 27.8 kDa, which had a purification fold of 12.08 and a specific activity of 4.47 μ/mg.