用微弹轰击法将GUS基因导入香蕉茎尖组织细胞

用在弹轰击法将外源ＤＮＡ导入香蕉（Ｍｕｓａ，ｓｐｐ）茎尖细胞，以ＧＵＳ基因作为报告基因，用Ｘ－Ｇｌｕｃ浴液对ＧＵＳ基因表达产物进行组织化学鉴定。样品材料细胞中发现有明显的蓝色斑点，而对照则没有。实验说明用微弹轰击法可以将外源基因导入香蕉茎尖组织并在其中成功表达，这为香蕉的外源基因导入工作提供了新的有效途径．     

Microbial synthesis and characterization of physiochemical properties of polyhydroxyalkanoates (PHAs) produced by bacteria isolated from activated sludge obtained from the municipal wastewater works in Hong Kong

The first objective of this study was the measurement of physical properties of P(3HB-co-3HV) copolymers with different (hydroxybutyrate) HB to (hydroxyvalerate) HV ratios produced by Bacillus cereus (TRY2) isolated from activated sludge. The 3HV PHBV copolymers were 0.05, 22.6, 39.2, 54.1, and 69.1 mol%, respectively. The second objective was to study possible wastewater treatment and production of PHAs at the same time by B. cereus (TRY2) and Pseudomonas spp. (TOB17) (both were isolated from activated sludge), recombinant Bacillus DH5α, and a combination of the above three bacteria. The results were satisfactory; the maximum COD and TOC of the sewage sludge reduced were 53.5% and 67.5%, respectively.     

Tasumatrols P – T,Five New Taxoids from Taxus sumatrana

The phytochemical investigation of the more polar fractions from the leaves and twigs of Taxus sumatrana (Taxaceae) afforded five new taxane diterpene esters, tasumatrols P–T ( 1 – 5 ) possessing an 11(15→1),11(10→9)‐diabeotaxane skeleton. Compounds 1, 4 , and 5 contain an α‐hydroxy group at C(14), while 3 has no OH group at either C(13) or C(14). Compound 2 is a natural 4,5‐acetonide derivative, while 4 has an unusual spiro‐connected 2‐hydroxy‐2‐phenyl‐1,3‐dioxolane ring. Ten known taxoids, were also isolated in the course of the chromatographic fractionation. Five additional new O‐acetyl derivatives 3a, 4a, 4b, 5a , and 5b were prepared from the taxanes 3 – 5 . The structures of all new compounds were established on the basis of their spectroscopic analyses. Compound 1 showed mild cytotoxic activity against human Hela and Daoy tumor cells.     

Optimization of the extraction of paclitaxel from Taxus baccata L. by the use of microwave energy

A simple and rapid microwave-assisted extraction (MAE) procedure was developed and optimized for the extraction of paclitaxel (Taxol) from the needles of yew trees Taxus baccata L. grown in Iranian habitats. The samples, immersed in a methanol-water mixture, were irradiated with microwaves in a closed-vessel system. The method was evaluated using a factorial design approach based on parameters such as extraction time, temperature, methanol concentration in water (v/v), and the ratio of grams of sample to 10 mL of solvent. Statistical treatment of the results revealed that the selected parameters were all significant except the extraction time. Optimum conditions would be 1.5 g samples in 10 mL solvent (90% methanol), an extraction temperature of 95 degrees C, and an extraction time of 7 min. The extracts has been analyzed by reverse-phase high-performance liquid chromatography with UV detection (LC/UV) at 227 nm for quantification. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for confirmation. The main advantage of the proposed MAE method versus conventional solvent extraction (CSE) are the considerable reductions in time (7 min versus 16 h) and in solvent consumption (20 mL versus 150 mL). The MAE procedure yielded extracts that could be analyzed directly without any preliminary clean-up or solvent exchange steps. Both extraction methods show RSDs lower than 10% and lead to comparable recoveries of paclitaxel (87-92%).     

龙牙蕉离体培养与植株再生的研究

为龙牙蕉短期内能获得大量种苗,应用离体培养技术进行种苗快繁,获得龙牙蕉(Musaspp.Longyajiao)吸芽离体培养试管植株,在MS+6 BA8mg·L-1+ADS30mg·L-1培养基中,诱导不定芽的分化效果较好,且生长正常.不定芽在1/2MS+6 BA2-3mg·L-1+NAA0 1mg·L-1培养基中诱导生根.在假根移植中,组培苗全部移栽成活.     

蜡样芽胞杆菌BCJB01粉剂防治番茄根结线虫的研究

为提高蜡样芽胞杆菌BCJB01粉剂对蔬菜根结线虫病的田间防治效果,采用添加营养基质、有机肥等方式,进行了蜡样芽胞杆菌BCJB01防治番茄根结线虫病的田间技术研究。结果表明,在整地时同时添加有机肥和营养基质的处理对番茄根结线虫的防治效果最好,防效为77.45%,优于对照药剂10%噻唑膦颗粒剂对番茄根结线虫的防治效果。     

林火干扰对栎类群落幼苗天然更新的影响

依据空间代替时间的方法,研究地表火干扰下不同恢复阶段栎类幼苗库的动态特征。结果表明:火后不同恢复阶段栎类群落内有木本幼苗25科37属49种,随着火烧迹地植被的恢复,乔木幼苗种类数量增多,灌木幼苗数量减少,但栎类幼苗始终占据优势;林下幼苗库的密度随恢复时间增加逐步变小,栎类幼苗密度则呈现出从高到低再升高然后变低的趋势,栎类幼苗密度在火后1年最高,平均达到(2.30±2.9)株/(10 m2);栎类幼苗密度变化出现2个过程,恢复1年与恢复5年、恢复10年与恢复15年幼苗密度之间有显著差异,但不同恢复阶段的栎类幼苗库与对照林相比没有显著差异;幼苗库不同恢复阶段的Shannon-Wiener指数(H′)之间有极显著差异。随演替时间的增加,乔木实生苗比例逐渐增加,乔木根蘖苗的比例不断减少。林火干扰对栎类Ⅰ、Ⅱ和Ⅲ的幼苗高度分配和苗木转化率有显著影响,但火烧干扰对Ⅳ级以上幼苗的高度分布和转化率影响不显著。     

变温层积处理对南方红豆杉种子生理生化特性的影响

脱除外被蜡质层的南方红豆杉种子,经低-暖-低变温层积结合植物生长调节剂及微量元素处理,120 d休眠解除.未层积处理的种子可供胚呼吸直接利用的可溶性糖等含量低.变温层积处理后,种子蛋白质、氨基酸和可溶性糖含量分别比对照提高了27.6%、80.0%和107.1%,脂肪含量降低了16.4%;种子脱氢酶、过氧化物酶和多酚氧化酶活性分别比对照提高了7.6%、129.3%和119.6%,蛋白酶活性降低了13.3%;解剖学特征表明,经变温层积处理,种子胚的发育渐进完善.实验结果提示种子贮藏物质特别是脂类物质的分解、转化和利用可能是南方红豆杉种子休萌解除的关键.     

小球藻培养条件的研究

对影响小球藻生长的NaHCO3、NaNO3、KH2PO4、维生素等4种主要营养因素进行了优化,获得了以海水为基础的优化培养基配方:NaHCO30.10g/L,NaNO30.225g/L,KH2PO40.005g/L,pH6.0.另外,适量添加土壤浸出液和维生素也会明显提高藻的产量.流加培养可以促进小球藻生物量的增加.     

山西天然南方红豆杉林及群落特点的研究

本文对南方红豆杉的地理分布和以它为优势种的森林植被在山西省的生态环境、植物区系组成及群落结构进行了初步研究并建议加强保护和发展.