表达广谱抗真菌蛋白转基因水稻秸秆的化学成分与纤维素结构

为了给表达广谱抗真菌蛋白转基因水稻的安全性评估提供基础数据,本文以表达广谱抗真菌蛋白转基因水稻转品1和转品8及非转基因七丝软粘(对照)为试材,对其秸秆化学成分进行分析,同时,采用傅立叶变换红外光谱(FTIR)和X-射线衍射(XRD)方法观察秸秆中不同部位纤维素结构的变化情况。研究结果显示:(1)转基因水稻转品1和转品8与对照在秸秆相同部位的化学成分含量不存在显著差异;(2)转基因水稻转品1和转品8及对照在秸秆相同部位纤维素的红外吸收峰形状基本一致,且品种间的吸收峰强度和结晶指数(O'KI和N·O'KI)也无显著差异;(3)转品1和转品8秸秆的X-射线衍射图与对照相似,且结晶度(CrI)与对照无显著差异。综上所述,广谱抗真菌基因的导入不会对水稻的化学成分、纤维素结构及晶体结构产生明显影响。     

Chemical composition and antifeedant activity of some aromatic plants against pine weevil (Hylobius abietis)

The pine weevil Hylobius abietis is an important pest causing severe damage to conifer seedlings in reforestation areas in Europe and Asia. Plants that have no evolutionary history with the pine weevil are of special interest in the search for compounds with a strong antifeedant activity. Thus, the essential oils of nine aromatic plants, viz Amomum subulatum, Cinnamomum tamala, Curcuma longa, Laurus nobilis, Ocimum basilicum, Origanum majorana, Origanum vulgare, Syzygium aromaticum and Trachyspermum ammi were extracted by hydrodistillation. The essential oil constituents were identified by gas chromatography–mass spectrometry, and antifeedant properties towards the pine weevil were assessed using choice feeding bioassay. The essential oils of C. longa, O. majorana, S. aromaticum and T. ammi showed an excellent antifeedant activity towards the pine weevil for 24 hr, whereas the essential oil of other plants showed the activity for 6 hr. There was a positive correlation between the amount of benzenoid compounds and the antifeedant activity of the essential oils. This study suggests that pine weevil non-host plant compounds have potential to be used for the protection of seedlings against pine weevil feeding. However, further study will be needed to explore the antifeedant activity of individual components and oils in the laboratory as well as in the field.     

Effect of nitrate supply on the facilitation between two salt-marsh plants (Suaeda salsa and Scirpus planiculmis)

在河口盐沼中,硝酸盐浓度和土壤盐分是两个主要的环境驱动因素,它们同时影响着植物物种之间的相互作用。然而,迄今为止,它们的交互作用对盐沼植物种间相互作用的影响还没有得到针对性的研究。在被漂洗过的河沙中种植盐地碱蓬(Suaeda salsa L.)和扁秆藨草(Scirpus planiculmis Fr.)的幼株,实验中设置三种处理：种间相互作用处理(混合培养或者单独培养)、三个盐度水平处理(1、50和100 mmol L^-1) 以及三个硝酸盐水平处理(0.5、5和10 mmol L^-1)。首先测量了所有植物植株的高度和生物量,然后分析了这两个物种的生长数据、种间相对关系指数和竞争重要性指数。在三个盐度处理中,盐地碱蓬和扁秆藨草的种间相互作用为种间促进。高浓度的硝酸盐促进了盐地碱蓬的生长,但并没有增强该物种的种间促进作用效果,特别是在低盐度处理中。然而,在高盐度处理中,高浓度的硝酸盐显著地将扁秆藨草的种间相互作用从促进转变为竞争。我们的结果表明,过量施用硝酸盐会在盐度梯度中改变胁迫梯度假说的预测,从而导致在盐沼中这两个物种共存的崩溃。这些发现有助于人们理解盐地碱蓬和扁秆藨草以及盐沼植物群落如何响应由人类活动导致的河口营养水平的改变。     

Chemical composition of reindeer forage plants in Svalbard and Norway

Several of the most important reindeer forage plants in Svalbard were analysed for content of minerals (Na, K, P, Ca, Mg, S, Cl, Fe, Cu, Mn, Zn, Mo and Co) and for content of ash, crude protein, crude fiber, ether extracts and nitrogen free extracts. Some forage plants were also examined in in vitro digestibility trials. The results were compared with results from similar analyses of alpine mountain plants from southern Norway. Also freshly voided fecal samples were analysed for the same components as the forage plants.
The Svalbard vegetation had a higher content of Na, Ca, Mg, Cl, Fe and Co, than similar plants from Southern Norway. The content of other elements examined seemed to be more equal in Norway and on Svalbard. Within the Svalbard area plants growing in limestone areas had the highest content of calcium and magnesium. Also plants growing on manured soil below bird cliffs appeared to have high nutritional value. It is furthermore concluded that the closeness to the sea as well as the occurrence of several plants with high mineral content, gave the Svalbard reindeer the possibility to further improve their mineral balance compared with continental reindeer. Also the dietary shift from lichens as a major dietary component in Norway, to mosses on Svalbard, may increase mineral intake, but may also have an inferior effect on digestibility.
Although balance experiments and carcass analyses of minerals in Svalbard reindeer are missing, it is concluded that Svalbard reindeer apparently had adequate intake of most mineral elements. In spite of low standing biomass of reindeer forage plants, the quality of the vegetation seemed to compare favourably with continental reindeer pasture.     

Chemical composition and antimicrobial activity of 2 Peruvian plants]

In this work we determined the hydrocarbon , sterol and triterpenoid composition of two plants used as antibacterial drug in traditional peruvian medicine, Berberis rariflora and Chenopodium multifidum. In both plants the presence of unsaturated hydrocarbons is very low, whereas the presence of odd hydrocarbons is considerable. The delta 7 sterols are more abundant than delta 5 sterols. We found also a great presence of stigmasterol derivatives in both plants, whereas lanosterol derivates are more abundant in B. rariflora. The microbiological tests shows for both plants an evident antibacterial activity against Gram(+) bacteria.     

Chemical constituents of plants from the genus Symplocos

The chemical constituents of Symplocos genus were reviewed with 90 structures and 28 references cited. These constituents include triterpenoids, flavonoids, lignans, phenols, steroids, alkaloids, and iridoids. Triterpenoids are the dominant constituents within the genus Symplocos, some of them exhibited antiproliferative effects. Some phenolic glycoside derivatives showed inhibitory activity against snake-venom phosphodiesterase I and human nucleotide pyrophosphatase phosphodiesterase.     

A new cytoplasmic polyhedrosis virus from the salt-marsh mosquito, Aedes cantator (Diptera: Culicidae)

The ultrastructure, development, and histopathology of a new cytoplasmic polyhedrosis virus of Aedes cantator are described. Virus particles measure 70 nm in diameter, are icosahedral in shape, and consist of a central electron-dense core surrounded by a capsid with six projections. Occlusion bodies are irregular in size (0.5–3.0 μm) and shape and contain several virus particles. Virus particles are assembled within an interconnecting network of fine filaments and are occluded by the deposition of a proteinaceous crystal around groups of mature virus particles within a virogenic stroma. Infections are confined to cells of the cardia, gastric ceca, and posterior portion of the midgut, which hypertrophy and frequently lyse. Infected larvae die during the fourth larval instar or as pupae. The prevalence of infection in natural field populations is less than 1%.     

Ankistromeces mariae n. g., n. sp. (Digenea: Sanguinicolidae) from Meuschenia freycineti (Monacanthidae) off Tasmania

Ankistromeces mariae n. g., n. sp. is described from Meuschenia freycineti (Monacanthidae), the six-spined leatherjacket, from off northern Tasmania. The new genus differs from the 21 other sanguinicolid genera in the combination of the anteriorly intercaecal and posteriorly post-caecal single testis, the presence of a cirrus-sac, the absence of an auxiliary external seminal vesicle, separate genital pores, the typically post-ovarian uterus and the H-shaped intestine. A. mariae is the first sanguinicolid to be reported from a monacanthid fish.     

Chemical composition of lipophylic compounds from the body surface of unfed adult Ixodes persulcatus ticks (Acari: Ixodidae)

Chemical compositions of ethereal extracts of the body surface of unfed male and female Ixodes persulcatus ticks (Acari: Ixodidae) were studied by gas chromatography using mass-spectrometric detection. More than 100 different organic compounds were detected. The predominant components were saturated fatty hydrocarbons, saturated and unsaturated fatty acids, aldehydes, squalene, cholesterol and cholesterol derivatives. A number of compounds found in I. persulcatus are known as components of pheromones or constituents of dermal gland secretions in tick species of the genus Amblyomma: nonanoic acid, saturated fatty acids having from 14 to 16 carbons, and squalene. Saturated fatty aldehydes have not been reported previously as body surface components of hard ticks. Substituted phenols were not found in the extracts, although they are known as common components of sex and attraction–aggregation–attachment pheromones in Amblyomma ticks. With a few exceptions (henicosanal, 2,4-holestadiene and two unidentified cholesterol derivatives), there was no marked difference in composition of surface components between male and female I. persulcatus. The possible role of the different chemical groups in communication between I. persulcatus ticks is discussed.