Isolation and identification of oligomers from partial degradation of lime fruit cutin

Complementary degradative treatments with low-temperature hydrofluoric acid and methanolic potassium hydroxide have been used to investigate the protective biopolymer cutin from Citrus aurantifolia (lime) fruits, augmenting prior enzymatic and chemical strategies to yield a more comprehensive view of its molecular architecture. Analysis of the resulting soluble oligomeric fragments with one- and two-dimensional NMR and MS methods identified a new dimer and three trimeric esters of primary alcohols based on 10,16-dihydroxyhexadecanoic acid and 10-oxo-16-hydroxyhexadecanoic acid units. Whereas only 10-oxo-16-hydroxyhexadecanoic acid units were found in the oligomers from hydrofluoric acid treatments, the dimer and trimer products isolated to date using diverse degradative methods included six of the seven possible stoichiometric ratios of monomer units. A novel glucoside-linked hydroxyfatty acid tetramer was also identified provisionally, suggesting that the cutin biopolymer can be bound covalently to the plant cell wall. Although the current findings suggest that the predominant molecular architecture of this protective polymer in lime fruits involves esters of primary and secondary alcohols based on long-chain hydroxyfatty acids, the possibility of additional cross-linking to enhance structural integrity is underscored by these and related findings of nonstandard cutin molecular architectures.     

Development and characterization of a new marine fish cell line from turbot (<Emphasis Type="Italic">Scophthalmus maximus</Emphasis>)

A new marine fish cell line, TK, derived from turbot (Scophthalmus maximus) kidney, was established by the method of trypsin digestion and subcultured for more than 50 passages over a period of 300 days. The TK cells were maintained in Minimum Essential Medium Eagle (MEM) supplemented with HEPES, antibiotics, fetal bovine serum (FBS), 2-Mercaptoethanol (2-Me), and basic fibroblast growth factor (bFGF). The suitable growth temperature for TK cells was 24°C, and microscopically, TK cells were composed of fibroblast-like cells. Chromosome analysis revealed that the TK cell line has a normal diploid karyotype with 2n = 44. Two fish viruses LCDV-C (lymphocystis disease virus from China) and TRBIV (turbot reddish body iridovirus) were used to determine the virus susceptibility of TK cell line. The TK cell line was found to be susceptible to TRBIV, and the infection was confirmed by cytopathic effect (CPE) and transmission electron microscopy, which detected the viral particles in the cytoplasm of virus-infected cells. Finally, significant green fluorescent signals were observed when the TK cells were transfected with pEGFP-N3 vector, indicating its potential utility for fish virus study and genetic manipulation.     

特早熟桃早春蕾选育研究

早春蕾桃属于早熟桃的全株变异。该品种树势健壮,花芽着生部位低,以中长果枝结果为主;幼树早果丰产性能好,果实的主要经济性状均优于春蕾桃,并且具有良好的遗传稳定性和较强的适应性和抗逆性,是目前成熟期最早的桃树优良品种,并于１９９９年３月,通过了山东省品种审定委员会审定。     

广东南岭国家森林公园旅游形象定位

本文通过对广东南岭国家森林公园基本情况的介绍，论述了旅游形象定位对于该森林公园的重要意义：从该森林公园的旅游形象基础、旅游环境、旅游资源特色、旅游市场感应等几个方面进行全面分析和系统综合．提出了合理的旅游形象定位和形象推广措施。     

移动智能体在森林病虫害专家系统中的应用研究

介绍智能体和移动智能体的发展及其技术理论。通过对移动智能体技术的分析,利用其移动性、能动性和交互性强的特点,提出将其应用到森林病虫害专家系统中,构建基于移动智能体的森林病虫害专家系统,进而提高专家系统的智能性,并对此系统的主要功能模块结构及其运行流程作了详细地阐述,对系统的发展前景作了展望。     

日本金竹文化论

日本的金竹文化鲜明体现在古代战争、传统节日、文学等方面,具有历史悠久、内涵深刻、表现广泛等特点。近代以后金竹文化低迷,但仍然是日本竹文化中最具神圣文化内涵的部分。     

Molecular identification of a phytoplasma associated with Sophora Root yellows

A phytoplasma infecting Sophora Root (Sophora alopecuroides) was detected and identified in Alar, Xinjiang Uygur Autonomous Region of China. Typical phytoplasma bodies were observed in sieve tubes of the diseased plants by transmission electron microscopy. A partial 16S rRNA gene and ribosomal protein (rp) genes containing rpl22 (rplV) and rps3 (rpsC) were amplified by direct and nested PCR. Based on the sequence similarity of the 16S rRNA and rp genes with accompanying phylogenetic analyses, the phytoplasma associated with Sophora Root yellows belongs to the 16SrI group (aster yellows group). Virtual RFLP analysis of these 16S rRNA and rp gene sequences showed distinct differences from those of reference phytoplasma strains representing previously described subgroups of the 16SrI group. Moreover, the similarity coefficient (0.92) of the RFLP profile of this phytoplasma was less than the threshold similarity coefficient (0.97) required for subgroup classification. Thus, the phytoplasma isolate of Sophora Root plants, designated as ‘SoRY’, represents a new subgroup. Furthermore, this is the first report of phytoplasma disease associated with Sophora Root plants.     

沙棘木蠹蛾性信息素的合成与林间诱蛾活性试验

利用气相色谱和触角电位初步确定沙棘木蠹蛾性信息素的主要组分为顺-7-十四碳烯醇(Z7-14:OH)、顺-7-十四碳烯基乙酸酯(Z7-14:Ac)和反-7-十四碳烯基乙酸酯(E7-14:Ac).应用本实验室人工合成的标准化合物在不同地点进行2年的田间试验,结果表明:以Z7-14:Ac、E3-14:Ac和E7-14:Ac 3种化合物按10:10:1配成含量为500 μg·个-1的诱芯,其诱蛾效果最好,诱蛾量能准确反映林间沙棘木蠹蛾发生与消长的情况.     

萍乡采矿废弃区退化森林的恢复与重建技术

借鉴国内外采矿废弃区退化森林的恢复重建经验,阐述了萍乡采矿废弃区退化森林的恢复、重建技术,并总结提出了萍乡采矿废弃区退化森林的恢复、重建的措施。     

几种小红栲变性淀粉的结构特性

目前世界上变性淀粉的年产量已经达到500万t左右,如美国为200万t以上,欧洲为90万t,日本在30万t以上;而我国在2000年变性淀粉的产量为35万t,仅为世界产量的7%,根本无法满足国内109万t以上的市场需求而每年都要从国外进口