Cloning and Sequence Analysis of Major Histocompatibility Complex Ⅰ Gene from Goose F1 of Fast-growth Lines

According to the multiple alignments identified major histocompatibility complex Ⅰ (MHC Ⅰ) gene conserved sequence registered in GenBank from the family ducks (Anatidae) anser waterfowl, a pairs of specific primers for the fragments of MHCⅠgene of goose F1 from fast-growth lines were designed and synthesized by Primer Premier 5.0. Using the genome DNA of goose F1 from fast-growth lines, the target gene fragment was obtained by PCR. To conduct sequencing of the fragments of MHCⅠgene of goose F1 from fast-growth lines and make sequence alignment and analysis of protein structure and function by bioinformatics, and research the characteristics of MHCⅠgene of goose F1 and the physicochemical properties of the protein. Bioinformatics was analyzed the nucleic acid data, deduced amino acid sequence and phylogenetic trees. The result of sequence analysis showed that the fragments of MHCⅠgene of goose F1 from fast-growth lines was 1036 bp in length, which coded 96 amino acids polyprotein. The homology were 93% and 83% with MHC Ⅰ gene and coding sequence of Wulong goose in NCBI respectively. There were 72 different bases sequence and 16 amino acids change. There also was higher homology with other poultry, and existed genetic relationship of Siji goose > chickens > ducks.The homology segment sequences corresponding to the fragments of MHCⅠ gene of goose F1 coded 96 amino acids protein, which molecular weight, PI, positively or negatively charged amino acid, estimated half-life, instability index, aliphatic index and average hydrophobicity were 11.342 ku, 5.32, 14, 17, 2.8 h, 34.92, 42.81, -1.066, respectively, and appeared 9 B cell epitopes, but contained no signal peptide. These results indicated that the protein for hydrophilic non-secreted proteins, had the high immunogenicity. In addition, The protein structure study indicated that alpha-helix, beta-sheet, beta-turn and random coil were 31.25%,16.67%, 14.58% and 37.50%, respectively. There existed amino terminal domain and carboxyl terminal domain in the tertiary structure. Therefore, MHC gene had significant difference between species and populations of individuals by the pathogen pressure in environment, and there were the interaction between polymorphism of MHC molecules and the diversity of antigenic peptide. MHC determined the differences of individual susceptibility to disease, and could be treated as a candidate gene for disease resistance.     

羊绒与羊毛的PCR-RFLP识别方法

羊绒价格昂贵,在销售中时常出现掺假现象,最常见的是用羊毛,因此精确识别羊绒和羊毛纤维的方法非常重要。本试验采用聚合酶链式反应-限制性片段长度多态（PCR-RFLP）的技术方法,利用提取的羊绒和羊毛线粒体基因组,根据细胞色素b（Cytochrome b）基因已知的DNA序列设计引物,通过内切酶SspⅠ进行酶切,得到不同的片段长度,根据酶切图谱鉴别羊绒和羊毛样品,用来进行羊绒掺假试验的定性检测。     

Enzymatic extraction of beta-glucan from oat bran cereals and oat crackers and optimization of viscosity measurement

The viscosity of the soluble fibre, β-glucan, has been shown to influence its ability to lower serum cholesterol and postprandial blood glucose levels. The impact of various amylases, proteases and lipase on the solubility and resulting viscosity of β-glucan extracted from oat bran cereals with a range of β-glucan concentrations and molecular weights was investigated. Addition of enzymes increased the final viscosity of high molecular weight β-glucan in cereals by facilitating the release of β-glucan from the food matrix. For cereals with partially depolymerized β-glucan, the addition of digestive enzymes decreased the final viscosity by eliminating the contribution of starch and protein to viscosity. Final viscosity varied depending on enzyme combinations including pancreatin, salivary and microbial α-amylases, microbial protease, porcine protease, trypsin and α-chymotrypsin. Addition of lipase did not significantly affect viscosity or solubility of β-glucan extracted from oat crackers. Addition of lichenase showed that β-glucan was the major contributor of viscosity to the system, with negligible interference from other components. The viscosity of the optimized protocol was compared to physiological results previously obtained. The viscosity of β-glucan extracted with pancreatin plus microbial α-amylase (pH 6.9) was predictive of LDL-cholesterol reduction (R² = 0.847) and glycemic response (R² = 0.883).     

定性PCR方法检测转基因玉米MON810转化事件的研究

转基因玉米MON810(Yield Gard R)是孟山都公司通过DNA重组技术和微注射轰击研发的一种具有对欧洲玉米螟(ECB;Ostrinia nublialis)有特殊抗性的转基因玉米品系,目前在世界各地已经得到广泛种植,为加强对该品系玉米的安全管理,本研究旨在建立MON810品系玉米的转化事件特异性定性PCR检测方法。根据MON810的插入序列信息,在3′端的侧翼序列处设计定性PCR检测的引物,检测MON810在其他几种常见转基因作物混合样品的特异性。结果表明,该方法具有很好的特异性。同时检测该引物系统的扩增灵敏度,结果表明,检测引物的灵敏度可达0.1%。建立的MON810特异定性PCR检测方法经全国7家实验室的验证,进一步证实该方法能够特异地检测出样品中的MON810转化事件,检测方法的灵敏度可达0.1%,且检测结果具有良好的可重复性和可重现性。MON810转化事件定性PCR检测方法的建立可满足于抗虫转基因玉米MON810及其衍生品种生物安全管理的需要。     

四川小麦品种高、低分子量麦谷蛋白基因和1B/1R易位的分子标记鉴定

为给四川小麦品质育种提供参考信息,利用7个HMW-GS、17个LMW-GS和1个1B/1R易位的特异分子标记,对105份2000年后育成的四川小麦品种进行上述基因检测。结果表明:(1)针对HMWGS,在Glu-A1位点,含Ax2*的品种有2份,频率为1.9%;在Glu-B1位点,含Bx7、Bx20、Bx17、By8和By9的品种分别有73、26、4、45和30份,频率分别为69.5%、24.8%、3.8%、42.9%和28.6%,未检测到含Bx7OE的品种;在Glu-D1位点,含Dx5的品种有65份,频率为61.9%。(2)针对LMW-GS,在Glu-A3位点,含Glu-A3a、Glu-A3b、Glu-A3c、Glu-A3d和Glu-A3f的品种分别有2、2、63、29和9份,频率分别为1.9%、1.9%、60.0%、27.6%和8.6%,未检测到含Glu-A3e和Glu-A3g的品种;在Glu-B3位点,含Glu-B3b、Glu-B3d、Glu-B3f、GluB3g和Glu-B3i的品种分别有18、10、1、75和1份,频率分别为17.1%、9.5%、1.0%、71.4%和1.0%,未检测到含Glu-B3a、Glu-B3c、Glu-B3e和Glu-B3h的品种。(3)含1B/1R易位的品种有36份,频率为34.3%。(4)组合6种和5种以上优质基因的品种分别有2份(频率为3.8%)和15份(频率为14.3%)。可利用这些品种作为亲本,在四川小麦品质育种中逐步导入优质基因Ax2*、Bx7、By8、Dx5、Glu-A3d、Glu-B3d、Glu-A3b和Glu-B3b,并淘汰1B/1R易位,优化四川小麦面筋优质基因组成。     

Effect of indaziflam on microbial activity and nitrogen cycling processes in an orchard soil

Indaziflam is a preemergent herbicide widely used for the control of weeds in pecan (Carya illinoinensis) orchards in the southwestern region of the United States. Given the paucity of data regarding the effect of indaziflam on the biochemical properties of soils supporting pecan production, this study was conducted to evaluate the effects of different application rates of indaziflam on soil microbial activity, diversity, and biochemical processes related to nitrogen (N) cycling. During two consecutive growing seasons (2015 and 2016), soil samples were obtained from experimental mesocosms consisting of soil-filled pots where pecan saplings were grown and treated with indaziflam applied at two different rates (25 and 50 g active ingredient (ai) ha^-1, with the higher rate being slightly lower than the recommended field application rate of 73.1 g ai ha^-1). Soil samples were collected approximately one week before and one week after herbicide application for determination of soil microbial biomass and diversity, N mineralization, and β-glucosaminidase activity. Soil samples collected from the control mesocosms without herbicide application were treated in the laboratory with two rates of indaziflam (75 and 150 g ai ha^-1) to determine the immediate effect on microbial activity. No significant effect of herbicide treatment on soil respiration and microbial biomass was detected. The results showed a slight to moderate decrease in microbial diversity (7% in 2015 and 44% in 2016). However, decreased β-glucosaminidase activity with herbicide treatment was observed in soils from the mesocosms (33%) and soils treated with indaziflam in the laboratory (45%). The mineral N pool was generally dominated by ammonium after indaziflam application, which was consistent with the drastic decrease (75%) in nitrification activity measured in the laboratory experiment. The results of this study indicate that indaziflam, even when applied at higher than recommended rates, has limited effects on soil microbial activity, but may affect N cycling processes.     

天然β-胡萝卜素提取工艺研究进展

β-胡萝卜素是维生素A的重要来源并且可作为食品着色剂,同时其突出的抗癌特性和抗氧化性使其成为日常膳食补充剂的理想选择。综述了国内外近十年来不同来源的生物原料中天然β-胡萝卜素提取工艺的研究概况,将其归纳为有机溶剂萃取法、超临界CO2萃取法、超声波辅助萃取法、微波辅助萃取法和酶解辅助萃取法,并对比了各种方法的优缺点,以期为今后β-胡萝卜素及其他天然色素特别是类胡萝卜色素的提取与开发提供参考。     

产β-甘露聚糖酶菌株的物理和化学诱变育种研究

[目的]比较产β-甘露聚糖菌株的物理和化学诱变育种效果。[方法]以产β-甘露聚糖酶的Bacillus subtilis WD23为出发菌株,利用紫外线诱变和甲基磺酸乙酯诱变的方法提高酶的活性。[结果]紫外线照射时间选为20～30s,诱变后酶活提高了8．72％;1％的甲基磺矗乙酯诱变10min,酶活提高了1．29％。[结论]紫外线诱变效果好于甲基磺酸乙酸,该研究中,物理诱变效果好于化学诱变。     

萝卜清除DPPH自由基活性研究

[目的]研究萝卜清除DPPH自由基的活性.[方法]通过对萝卜叶水提物、水提物不同极性部位萃取物、萝卜中脂肪油类有效成分β-谷甾醇进行清除DPPH（1,1-二苯基-2-三硝基苯肼）自由基活性测试,对萝卜的抗氧化能力进行评价.[结果]以柠檬酸为对照其清除能力大小顺序为：乙酸乙酯层＞二氯甲烷层＞萝卜叶水提物＞β-谷甾醇＞石油醚层＞柠檬酸.[结论]萝卜具有较好的抗氧化能力.     

三孢布拉氏霉中β-胡萝卜素的提取研究

[目的]确定从三孢布拉氏霉干菌体中提取β-胡萝卜素的溶剂种类及提取条件。[方法]以发酵所得的三孢布拉氏霉干菌丝体为原料,通过单因素试验考察了不同溶剂种类、料液比、提取时间和提取温度对β-胡萝卜素提取得率的影响。[结果]试验得出,乙醇提取得率较低,而丙酮、石油醚、乙酸乙酯和正己烷4种溶剂从三孢布拉氏霉干菌体中提取β-胡萝卜素的得率几乎相同。从价格因素考虑,选取石油醚作为提取溶剂。适宜的提取条件为料液比1∶15 g/ml,提取时间2 h,提取温度40℃,提取得率可达约16 mgβ-胡萝卜素/g干菌体。[结论]该研究可为利用三孢布拉氏霉发酵法生产天然β-胡萝卜素提供依据和参考。