胶陀螺的光敏活性组分

用石油醚、氯仿、乙酸乙酯和丙酮对胶陀螺子实体进行梯度提取,得到的粗提物做光敏活性药理试验,结果表明:胶陀螺的氯仿和乙酸乙酯粗提取物有明显的光敏活性。将氯仿和乙酸乙酯的粗提物分别用不同比例的氯仿—甲醇进行反复柱层析,同时配合光敏活性药理试验,得到6个有光敏活性的组分,分别为c2、c3、c4、c5、c6和c11。将6个组分合并后继续分离,最终得到1个有橙黄色荧光点的成分,对其进行光敏活性药理试验,结果证明其为胶陀螺的光敏活性成分。     

胶陀螺的化学成分及药理作用研究概况

胶陀螺[Bulgaria inquinans(Pers.)Fr.]作为一种长白山地区食药兼用的真菌,在夏、秋季节常见于蒙古栎的倒木及树桩上。文中将近年来国内外对胶陀螺的化学成分和药理作用的研究进行了综述,现已从胶陀螺中分离得到了苯并[j]荧蒽类、azaphilone类、醌类、甾类、萜类、苯丙素类等50多种化合物;在药理活性方面,胶陀螺具有抑菌、抗癌、光敏、抗疟疾、抗氧化、止痒、杀虫、抗血瘀等活性,而其中胶陀螺的光敏活性作为其特有的作用一直被关注,并已确定了光敏活性的有效组分。     

硫酸化分级香菇多糖抗氧化活性研究

提取香菇子实体多糖,用浓硫酸法进行结构修饰,经不同分子量超滤膜超滤分离得到6种不同组份的硫酸化香菇多糖,检测这6种组份抗氧化活性。结果表明,硫酸化香菇多糖具有抗氧化活性,在1-10mg/mL的浓度范围内呈量效关系,且不同分子量组份活性有差异。     

化橘红黄酮类化合物抑制亚硝化反应活性研究

根据超声波最佳提取工艺条件提取得到化橘红总黄酮,经乙酸乙酯萃取分为酯溶性和水溶性两部分,比较它们对亚硝化反应的抑制作用,并分别采用硅胶柱层析对酯溶性成分分离纯化,采用大孔吸附树脂法对水溶性成分进行分离纯化,得到4个主要的黄酮类化合物,研究它们对亚硝化反应的抑制作用,以期得到抑制亚硝化活性较强的化合物。结果表明化橘红总黄酮提取率可达26.42%,酯溶性和水溶性部分均能阻断亚硝胺的合成及清除亚硝酸盐,其中水溶性黄酮提取物作用较强,分离得到的4个黄酮类化合物中柚皮苷的抑制作用较强,对亚硝胺的合成的最大阻断率可达94.7%,对亚硝酸盐的最大清除率可达92.3%。     

蒙古口蘑子实体凝集素性质初步研究

对蒙古口蘑干燥子实体研磨后,用磷酸盐缓冲液浸提,得到蒙古口蘑子实体的凝集素粗提物。对其性质进行分析表明,蒙古口蘑子实体凝集素对牛血和羊血都能凝集,且对羊血的凝集作用较强;D-果糖、β-葡萄糖、半乳糖和木糖对蒙古口蘑子实体凝集素均具有抑制作用;弱酸或弱碱性浸提液有利于凝集素的提取;蒙古口蘑子实体凝集素具有一定的热稳定性,直到70℃以后凝集红细胞的活力才丧失;凝集素的凝集活性对Ca2+、Mg2+、Mn2+和Fe3+这4种离子有不同程度的依赖。     

茶蜂花粉抗氧化活性与成分

本实验研究了茶蜂花粉的抗氧化活性和功效成分。茶蜂花粉85%乙醇回流提取,经过石油醚、乙酸乙酯、正丁醇依次萃取,得到石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物以及萃余物4个部分,用D-半乳糖诱导衰老小鼠模型检测茶蜂花粉不同组分的抗氧化活性,采用多种色谱方法分离具有抗氧化活性的成分,利用核磁共振方法鉴定各单体的化学结构。结果表明:茶蜂花粉乙醇提取物、乙酸乙酯萃取物具有明显的抗氧化作用,乙酸乙酯萃取物经MCI柱层析,得到30%、50%、70%三个乙醇洗脱组分,其中30%乙醇洗脱组分具有显著抗氧化活性,从该洗脱部分得到三个单体化合物,经鉴定为:槲皮素、山奈素-3-O-芸香糖苷、山奈酚-3-O-(2″,3″,4″-O-三对羟基桂皮酰基)-β-D-吡喃葡萄糖苷,推测茶蜂花粉具有抗氧化活性的成分主要为黄酮类化合物。     

三七二醇型皂苷氧化降解产物衍生物的合成及其抗肿瘤活性研究

本研究以三七二醇型皂苷原料,通过琼斯氧化得到化合物1,将化合物1的3位羰基经还原胺化反应转化为氨基得到化合物4,再用化合物4与酰化试剂反应得到化合物5~8,此外还通过其它两种反应得到化合物2和3,总共8个化合物,其中6个化合物未见文献报道,结构均经过核磁共振、质谱确证。所得化合物用MTS法对人白血病细胞株HL-60、肝癌细胞株SMMC-7721、肺癌细胞株A-549、乳腺癌细胞株MCF-7、结肠癌细胞株SW480等肿瘤细胞株进行抗肿瘤活性评价。药理活性评价结果显示,化合物3有一定的抗肿瘤活性,值得进一步研究。     

蛹虫草子实体活性成分的分离鉴定

蛹虫草具有悠久的食药用历史,但关于其活性成分的种类仍知甚少。本文采用大孔树脂、硅胶柱、HPLC等色谱技术对蛹虫草Cordyceps militaris子实体粗提物进行分离纯化,从中得到3个化合物。通过波谱数据分析,化合物1–3分别被鉴定为：虫草素（3’-脱氧腺苷）（1）,色氨酸（2）和5,5’-dibuthoxy-2,2’-bifuran（3）,杂环化合物3为首次从蛹虫草子实体中获得。对化合物进行抗菌活性测定发现,虫草素和5,5’-dibuthoxy-2,2’-bifuran对枯草芽孢杆菌和大肠杆菌都有显著的抑菌活性,但是它们对酿酒酵母均未表现出明显抑菌活性。     

栽培条件对灵芝子实体的三萜组成及其活性的影响

以不同灵芝品种、不同栽培基质、不同管理方式、不同生长时期获得的灵芝子实体为原料,用95%乙醇超声提取,对提取物进行了含量测定、三萜组成分析和体外抗肿瘤实验。结果表明,不同子实体醇提物中三萜和甾醇类物质的含量在4.60-6.20mg/g之间;高效液相分析发现10种三萜化合物的种类和含量在样品间存在明显差异。所有灵芝子实体醇提物对肿瘤细胞L1210的增殖均有一定的抑制作用,开伞期的灵芝子实体醇提物抑制肿瘤增殖的活性优于其他生长时期。     

一种白僵菌代谢产物中生物活性物质的研究 Ⅰ.具有清除自由基的活性物质的分离和制备

通过对白僵菌Beauveriasp.的液体培养及生物活性测定,发现该菌代谢产物具有较强的清除自由基的活性,我们用甲醇成功地提取出该活性成分,同时用色谱等方法对该活性成分进行了分离和制备,并用高压液相色谱法和DPPH薄层试验对其纯度及活性进行了检验,得到了具消除自由基活性的纯化合物P-24-3。     

Effects of environmental factors, age and genotype on sperm production and semen quality in Bos indicus and Bos taurus AI bulls in Brazil

The effects of ambient temperature and humidity, month, age and genotype on sperm production and semen quality in AI bulls in Brazil were evaluated. Data from two consecutive years were analyzed separately. Seven Bos indicus and 11 Bos taurus bulls from one artificial insemination (AI) center were evaluated in Year 1 and 24 B. indicus and 16 B. taurus bulls from three AI centers were evaluated in Year 2. Ambient temperature and humidity did not significantly affect sperm production and semen quality, probably because there was little variation in these variables. Month accounted for less than 2% of the variation in sperm production and semen quality. Increased bull age was associated with decreased sperm motility (P<0.10) and increased minor sperm defects (P<0.001) in Year 1. B. indicus bulls had greater (P<0.005) sperm concentration than B. taurus bulls in both years (1.7×10⁹/ml versus 1.2×10⁹/ml in Year 1 and 1.6×10⁹/ml versus 1.2×10⁹/ml in Year 2, respectively). Ejaculate volume was not significantly affected by genotype in Year 1 (6.6 ml versus 6.9 ml in B. indicus and B. taurus bulls, respectively), but B. indicus bulls had greater (P<0.05) total (11.4×10⁹ versus 8.2×10⁹) and viable (6.7×10⁹ versus 4.9×10⁹) numbers of spermatozoa in the ejaculate than B. taurus bulls. In Year 2, B. taurus bulls had greater (P<0.05) ejaculate volume than B. indicus bulls (8.2 ml versus 6.7 ml, respectively) and total and viable number of spermatozoa in the ejaculate were not significantly different between genotypes (10.3×10⁹ versus 9.1×10⁹ and 6.1×10⁹ versus 5.4×10⁹ in B. indicus and B. taurus bulls, respectively). Sperm motility was not significantly affected by genotype (mean, 59%). In Year 1, B. indicus bulls tended (P<0.10) to have more major sperm defects and had more (P<0.05) total sperm defects than B. taurus bulls (11.8% versus 8.7% and 13.6% versus 10.0%, respectively). In Year 2, B. indicus bulls tended (P<0.10) to have more total sperm defects than B. taurus bulls (16.2% versus 13.3%, respectively). In conclusion, neither ambient temperature and humidity nor month (season) significantly affected sperm production and semen quality. B. indicus bulls had significantly greater sperm concentration and B. taurus bulls had significantly fewer morphologically defective spermatozoa.     

Laboratory investigations on the potential of entomopathogenic fungi for biocontrol of Helicoverpa armigera (Lepidoptera: Noctuidae) larvae and pupae

The susceptibility of third instar Helicoverpa armigera to seven strains of three entomopathogenic fungal species, i.e. Metarhizium anisopliae, Beauveria bassiana and Paecilomyces fumosoroseus, was tested under laboratory conditions using the larval immersion method. High efficacies ranging from 68 to 100% corrected mortality were recorded with more profound effects in treatments with B. bassiana and P. fumosoroseus strains. The median lethal concentration (LC₅₀) for L3 was 6.0×10⁵ in M. anisopliae 79, 1.5×10⁵ in B. bassiana 124 and 4.2×10⁴ in P. fumosoroseus 14. These three strains were further used to characterize the age-dependent mortality of different larval stages (L2-L5) and the effect against pupae of H. armigera. Larval stages did not differ in their mortality but differed i in median lethal time, with shorter values recorded in the second instar. Tested fungi also caused a high reduction between 74.4 and 100% in the emergence of pupae using the soil inoculation method and the pupal immersion technique. All three fungal species, especially P. fumosoroseus, have a high potential for biocontrol of H. armigera larvae and also as a soil treatment targeting the pupae.     

阔叶丰花草与2种菊科植物之间的化感作用

阔叶丰花草是一种适用于华南果园生草控草的一年生植物。为了揭示阔叶丰花草与果园常见杂草之间的竞争关系,研究了阔叶丰花草与两种菊科植物(胜红蓟和白花鬼针草)之间的化感作用。结果表明: 10～50 mg·mL^-1的阔叶丰花草水浸液处理显著抑制胜红蓟和白花鬼针草种子萌发和幼苗生长,胜红蓟和白花鬼针草的胚根长分别比对照降低57.4%～90.2%和57.3%～62.3%。胜红蓟和白花鬼针草水浸液对阔叶丰花草种子萌发也有较强的化感效应,在50 mg·mL^-1的浓度处理下,阔叶丰花草种子几乎不能萌发。经10 mg·mL^-1阔叶丰花草水浸液处理30 d后,胜红蓟播种苗的净光合作用、株高和生物量分别比对照降低15.2%、20.6%和41.5%,白花鬼针草播种苗的生物量也出现下降趋势;但胜红蓟和白花鬼针草水浸液处理对阔叶丰花草播种苗生长的影响均不显著。在混种条件下,阔叶丰花草的生物量与单种的水平相当,胜红蓟和白花鬼针草的生物量则分别比单种降低86.0%和27.1%。与胜红蓟和白花鬼针草相比,阔叶丰花草的化感优势在于除了能抑制对方的种子萌发,也能抑制其植株生长。     

巴茅草水浸提液对3种作物种子萌发及幼苗生长的化感作用

本文以发芽率、发芽速度指数、发芽指数、根长、茎长和生物量为种子萌发和幼苗生长参数,研究不同生长时期巴茅草叶片和茎秆水浸提液对白菜、生菜、水稻的化感作用。结果表明: 巴茅草叶水浸提液化感作用强于茎秆水浸提液,叶水浸提液处理后受体植物的发芽指数和生物量均显著低于茎水浸提液。枯萎期巴茅草的化感作用强于生长旺盛期。不同浓度巴茅草叶水浸提液对3种作物的化感作用存在明显的量效关系,浸提液浓度越高,巴茅草的化感抑制作用越强。巴茅草叶水浸提液对白菜和生菜各萌发指标100%抑制的浓度分别为0.075和0.10 g·mL^-1;而0.10 g·mL^-1巴茅草叶水浸提液对水稻发芽率、发芽速度指数、发芽指数的抑制率分别为13.8%、27.2%、19.3%。巴茅草叶水浸提液对白菜和生菜各生长指标100%抑制的浓度分别为0.05和0.10 g·mL^-1;而0.10 g·mL^-1巴茅草叶水浸提液对水稻根长、茎长、生物量的抑制率分别为64.6%、92.9%、21.8%。结合种子萌发和幼苗生长的综合化感指数,3种供试作物对巴茅草化感作用的敏感程度为白菜>生菜>水稻。     

武夷山自然保护区土壤可培养芽胞杆菌 的物种多样性及分布

为了解武夷山自然保护区土壤中可培养芽胞杆菌的分布状况, 2012年6月从该保护区的黄岗山顶部、中部、底部和桐木关、挂墩、大竹岚等6个地点采集土样75份。用80℃水浴加热、稀释平板法进行芽胞杆菌的分离, 并根据16S rRNA基因序列分析对菌株进行初步鉴定。从土样中分离出芽胞杆菌418株, 鉴定为8个属42个种, 其中Bacillus属的种数最多, 有20种, Paenibacillus属和Lysinibacillus属分别有8种和7种。不同地点分离到的芽胞杆菌在种类、数量上存在差异: 从大竹岚土壤中分离到的芽胞杆菌种类最多, 从黄岗山中部和底部分离到的种类数则较少; 挂墩、大竹岚土壤中芽胞杆菌的数量较大, 达3.6×10⁶ cfu/g以上, 而黄岗山顶部和中部土壤中的数量则少于4.9×10⁵ cfu/g。Bacillus cereus、B. mycoides、B. thuringiensis和Lysinibacillus xylanilyticus等4个种在6个地点的土样中均有分离到, 其中B. thuringiensis、L. xylanilyticus是该保护区土壤中的优势种。桐木关土壤中芽胞杆菌的种类多样性和均匀度指数都比其他5个地点的高, 而挂墩土壤中芽胞杆菌的Shannon-Wiener多样性、均匀度和优势度指数都最低。B. mycoides和B. thuringiensis的数量与海拔显著相关, 相关系数分别为0.852和-0.834, B. cereus、B. mycoides、B. thuringiensis的分离频度与海拔的相关性极显著, 相关系数分别为0.960、0.952和-0.931。研究结果表明, 武夷山自然保护区土壤中可培养芽胞杆菌的种类丰富、数量较大, 具有较高的多样性。     

基于游离质粒的木糖诱导型枯草芽孢杆菌转化体系的建立及其应用

枯草芽孢杆菌（Bacillus subtilis）作为食品级安全菌株,因其具有理化特征清晰、培养发酵方便等特点,广泛应用于异源蛋白质的高效表达以及高附加值物质的合成。传统的B. subtilis遗传转化方法存在操作流程繁琐、效率低等缺点,因此,开发方便高效的遗传转化系统具有重要意义。转录因子ComK被证实能调控B. subtilis感受态的形成,并在B. subtilis高效转化中有重要作用。构建1个含有木糖诱导启动子P_xyl调控comK表达的穿梭质粒pUBC01?P_xyl?comK的菌株B. subtilis K1,经木糖诱导条件优化后,质粒pHY300?p43?egfp的转化效率达到4.8×10³ CFU·μg^-1。此外,质粒pUBC01?P_xyl?comK可在无胁迫条件下连续培养及消除。木糖诱导感受态体系及质粒消除极大地提高了芽孢杆菌基因编辑和菌株改造的便捷性,同时增强了菌株尤其是生产菌株的性状稳定性。     

Photogeneration of singlet oxygen (1O2) and free radicals (Sen·-, O·-2) by tetra-brominated hypocrellin B derivative

To improve photodynamic activity of the parent hypocrellin B (HB), a tetra-brominated HB derivative (compound 1) was synthesized in high yield. Compared with HB, compound 1 has enhanced red absorption and high molar extinction coefficients. The photodynamic action of compound 1, especially the generation mechanism and efficiencies of active species (Sen^·-, O^·-₂ and ¹O₂) were studied using electron paramagnetic resonance (EPR) and spectrophotometric methods. In the deoxygenated DMSO solution of compound 1, the semiquinone anion radical of compound 1 is photogenerated via the self-electron transfer between the excited and ground state species. The presence of electron donor significantly promotes the reduction of compound 1. When oxygen is present, superoxide anion radical (O^·-₂) is formed via the electron transfer from Sens^·- to the ground state molecular oxygen. The efficiencies of Sens^·- and O^·-₂ generation by compound 1 are about three and two times as much as that of HB, respectively. Singlet oxygen (¹O₂) can be produced via the energy transfer from triplet compound 1 to ground state oxygen molecules. The quantum yield of singlet oxygen (¹O₂) is 0.54 in CHCl₃ similar to that of HB. Furthermore, it was found that the accumulation of Sens^·- would replace that of O^·-₂ or ¹O₂ with the depletion of oxygen in the sealed system.     

Development of a rapid and sensitive immunoassay for detection and subsequent recovery of Bacillus anthracis spores in environmental samples

Bacillus anthracis is considered a major threat as an agent of bioterrorism. B. anthracis spores are readily dispersed as aerosols, are very persistent, and are resistant to normal disinfection treatments. Immunoassays have been developed to rapidly detect B. anthracis spores at high concentrations. However, detection of B. anthracis spores at lower concentrations is problematic due to the fact that closely related Bacillus species (e.g., B. thuringiensis) can cross-react with anti-B. anthracis antibodies, resulting in false positive detections. Subsequent polymerase chain reaction (PCR) analysis is required to differentiate virulent strains. We report here on a protocol for the rapid, sensitive detection of B. anthracis spore using the Integrating Waveguide Biosensor followed by a method for the rapid release and germination of immunocaptured spores. A detection limit of ca. 10³ spores was achieved by incubating spores simultaneously with capture and detection antibodies (“liquid-phase” assay) prior to capture on capillary tubes/waveguides. Subsequent incubation with BHI broth directly in capillary tubes allowed for rapid germination, outgrowth, and release of spores, resulting in vegetative cells for PCR analysis.     

杨树桑黄饮片水提物对免疫低下小鼠的免疫功能的影响

探究桑黄饮片水提物对环磷酰胺所致免疫低下小鼠的免疫功能的影响。本研究以桑黄饮片为原料,采用超声和沸水提取方法得到桑黄饮片水提物,注射环磷酰胺造成小鼠免疫功能低下,通过测定脾脏和胸腺指数、血清免疫球蛋白和细胞因子、脾淋巴细胞增殖、碳粒廓清等实验,对免疫低下小鼠的免疫功能进行研究评价。结果表明,灌胃桑黄饮片水提物的小鼠与模型组相比,免疫器官指数、血清中免疫球蛋白含量、细胞因子水平、脾淋巴细胞增殖程度、巨噬细胞的吞噬速率和吞噬指数、小鼠耳肿胀度均有提高,脾脏苏木精-伊红(HE)染色也表明桑黄饮片水提物可以改善环磷酰胺导致的脾脏组织病理状态。本研究表明桑黄饮片水提物对环磷酰胺所致的免疫抑制小鼠具有良好的免疫保护作用,为桑黄饮片扩大临床应用提供实验依据。     

Horizontal Transmission of the Entomopathogenic Fungus Beauveria bassiana among the Spruce Bark Beetle, Ips typographus (Col., Scolytidae) in the Laboratory and under Field Conditions

In laboratory and field cage experiments, the horizontal transmission of the entomopathogenic fungus Beauveria bassiana (Boverol®) between adults of the spruce bark beetle Ips typographus was examined. In a laboratory experiment, conidia transfer between treated and untreated beetles at different ratios resulted in 96% mortality (MST 4.3 days) at a ratio of 1:1 and 90% mortality (MST 4.5 days) at a ratio of 1:2. At ratios of 1:5, 1:10 and 1:20, the mortalities at 7 days were 83, 77 and 75%, respectively. In a second laboratory experiment, the efficacy of B. bassiana was investigated after transmission from contaminated to healthy beetles over a period of 5 days. Two weeks later, the mortality of treated and untreated beetles was 99% (control mortality was 44%), while the rate of mycosis was 79% in the treatment compared to 10% in the control beetles. A single contact between one treated male (2.0×10⁵ conidia/beetle) and an untreated female was found to be sufficient to transmit a lethal dose of B. bassiana of about 1.2×10⁴ conidia. Two experiments in field cages in a spruce stand demonstrated horizontal transmission of B. bassiana (Boverol®) between beetles. In the first experiment the transmission was investigated following the introduction of B. bassiana-inoculated beetles into a population of untreated beetles. Significant reductions were observed in the length of maternal galleries, and the number of larvae and pupae. In the second field cage experiment, natural populations of beetles were lured into a flight cage using a pheromone trap, and treated with B. bassiana or left untreated on alternate days. In this experiment, significant reductions were observed in the number of bore holes and the length of maternal galleries, while no larvae, pupae or juveniles were found under the bark of spruce trunks in the Boverol® transmission treatment. It is concluded that B. bassiana has potential for control of I. typographus, and further field experiments are warranted to investigate its efficacy under more practical conditions.