干旱胁迫对黄芪植株生长中黄酮类成分积累的影响

以3年生蒙古黄芪植株为材料,采用盆栽法模拟干旱处理,研究水分胁迫对黄芪生理状态以及其根、茎、叶中毛蕊异黄酮、毛蕊异黄酮葡萄糖苷、芒柄花素和芒柄花苷4种黄酮类化合物含量的影响。结果显示:(1)毛蕊异黄酮和毛蕊异黄酮葡萄糖苷在黄芪根、茎、叶均有分布,不同器官的毛蕊异黄酮葡萄糖苷含量表现为根叶茎,而毛蕊异黄酮含量则是叶茎根。(2)干旱胁迫下,黄芪根中毛蕊异黄酮葡萄糖苷和芒柄花苷在胁迫第8~12天有一定的积累;叶中的毛蕊异黄酮则在干旱第4~8天有明显的积累,而毛蕊异黄酮葡萄糖苷则没有明显变化。研究发现,4种黄酮类化合物在黄芪各器官中分布和含量不尽相同,同一器官中不同黄酮类化合物对干旱胁迫的响应规律也存在差异;适度的干旱胁迫能够促进黄芪毛蕊异黄酮葡萄糖苷的积累,但过度干旱胁迫则不利于其积累。     

干旱胁迫对蒙古黄芪和膜荚黄芪不同器官黄酮类成分积累的影响

以一年生蒙古黄芪和膜荚黄芪幼苗为材料,采用盆栽控水试验,研究连续干旱胁迫12 d及恢复浇水对2种黄芪生理状态及其根、茎、叶中毛蕊异黄酮葡萄糖苷和毛蕊异黄酮2种黄酮类成分含量的影响。结果显示:(1)干旱胁迫明显抑制了2种黄芪地上部生长,对其根系生长则无明显影响;土壤相对含水量在连续干旱处理4 d后就下降,但2种黄芪的叶片相对含水量只有在中度干旱胁迫(连续干旱8～12 d)下才下降,且膜荚黄芪的下降幅度大于蒙古黄芪。(2)干旱胁迫下,蒙古黄芪和膜荚黄芪根和叶中的SOD和POD活性均呈先上升后下降的趋势,且蒙古黄芪根和叶中的SOD和POD活性均低于膜荚黄芪。(3)干旱胁迫下,膜荚黄芪不同器官中的毛蕊异黄酮葡萄糖苷含量表现为叶茎根,而蒙古黄芪根、茎和叶之间毛蕊异黄酮葡萄糖苷含量差异不明显;膜荚黄芪中的毛蕊异黄酮含量表现为叶大于茎,在蒙古黄芪中则表现为茎大于叶;而且2种黄芪的黄酮类成分在同一器官中的积累也有一定的差异性。研究认为,蒙古黄芪的抗旱性高于膜荚黄芪,适度的干旱胁迫能够促进黄芪器官中毛蕊异黄酮葡萄糖苷和毛蕊异黄酮的积累。     

引种栽培黄芪药材中主要黄酮类成分含量比较研究

种质资源的筛选和评价对于黄芪的规范化栽培与种植具有重要意义。本研究即分别采用分光光度法、高效液相色谱法测定引种至山西浑源黄芪道地产区不同来源黄芪药材中总黄酮和毛蕊异黄酮、芒柄花素的含量,并进行相关性分析。结果表明:上述成分不仅仅与黄芪栽培方式、产地有关,还与种质来源密切相关;山西、陕西地区黄芪种质适宜在当地栽培和野生种植,而甘肃、内蒙古黄芪引种到山西浑源地区黄酮类物质含量较原产地为高,适宜大面积引种;黄芪药材中毛蕊异黄酮和芒柄花素的含量呈显著的正相关。该研究结果将为黄芪的规范化种植、优良品种选育及质量评价体系的优化提供新的科学依据。     

黄芪化学成分与生态因子的相关性

以主成分分析(PCA)和相关性分析(CA)法研究黄芪中主要有效成分与生态因子的相关性,探究影响黄芪主要成分积累的生态因子.结果表明: 山西产地黄芪中的黄芪甲苷、毛蕊异黄酮苷、芒柄花苷、山奈酚和黄芪多糖的含量显著高于内蒙古和甘肃两地.影响黄芪化学成分含量的气候因子主要为年均相对湿度、年日照时数及7月均温.影响黄芪化学成分含量的土壤元素主要为钙,且钙在一定范围内与毛蕊异黄酮苷、山柰酚、芒柄花苷、槲皮素、黄芪多糖的含量呈负相关.     

黄芪种子萌发及萌发后生长过程中黄酮类化合物合成的动态变化

在对膜荚黄芪和蒙古黄芪种子萌发和萌发后生长时期进行划分的基础上,研究了黄芪中3种主要黄酮类化合物芒柄花素、毛蕊异黄酮和毛蕊异黄酮苷在萌发和萌发后生长过程中含量的变化。为了弄清黄酮含量变化的机制,我们还对黄芪中黄酮生物合成途径酶的转录水平做了研究。结果表明,在种子萌发和萌发后生长阶段,两种黄芪中均出现了明显的黄酮类化合物累积增加的情况。通过检测黄酮类物质生物合成途径酶基因的转录表达水平,我们发现萌发阶段蒙古黄芪中黄酮类物质积累增加主要由上游途径酶基因的表达水平升高引起,而膜荚黄芪中则几乎涉及到所有途径酶。此外,我们还发现萌发后生长阶段中,两种黄芪中合成途径酶基因转录对黄酮类物质含量的调控则选择性地存在时间延迟效应。     

HPLC-UV-ELSD法同时测定黄芪中黄芪皂苷和黄酮类成分

建立HPLC-UV-ELSD法同时测定黄芪中黄芪皂苷Ⅰ、黄芪皂苷Ⅱ、黄芪皂苷Ⅲ、黄芪甲苷、毛蕊异黄酮葡萄糖苷、刺芒柄花苷、毛蕊异黄酮的含量,并比较四种不同供试液中7种成分的含量差异,实验采用Agilent 5 TC-C_(18)色谱柱(250 mm×4.6 mm,5μm),0.3%甲酸水溶液-乙腈进行梯度洗脱,流速为1.0 mL/min,检测波长254 nm;柱温30℃,漂移管温度70℃。在该色谱条件下,黄芪中7种成分能得到较好的分离,稳定性,重复性及精密度良好。本方法能简便、快捷、有效的测定黄芪药材中多种成分含量。大孔树脂制备供试品中黄芪皂苷和黄酮类成分更高,说明碱化处理对黄芪中的成分含量产生了一定影响。     

膜荚黄芪中的异黄酮化合物

从上海崇明产膜荚黄芪(Astragalus membranaceus(Fisch.)Bunge)根的乙醇提取物中分离鉴定了6个异黄酮化合物:8,3＇-二羟基-7,4＇-二甲氧基异黄酮、奥刀拉亭-7-O-β-D-葡萄吡喃糖甙、芒柄花素、7,3＇-二羟基-8,4＇-二甲氧基异黄酮、毛蕊异黄酮和毛蕊异黄酮-7-O-β-D葡萄吡喃糖甙。其中,前两个为新化合物。     

干旱胁迫对蒙古黄芪生物量及其根际微生物种群数量的影响

以‘武川’和‘浑源’2个蒙古黄芪地方品种为试材,采用盆栽控水模拟干旱处理,研究干旱胁迫下黄芪生物量及根际微生物数量的动态变化规律。结果显示：随着干旱程度的加剧,2个品种的根际细菌和放线菌种群数量均呈先上升后下降的变化趋势,真菌数量却呈现持续减少,而细菌数量在根际微生物区系中占绝对优势;随干旱强度升高,2个品种黄芪根、叶组织相对含水量均表现出明显的逐渐下降趋势,其地上部生物量、根系生物量也均降低,而根冠比却逐渐增大;黄芪根际各菌类数量与其地上生物量存在显著正相关关系,但与根系生物量无显著相关关系。研究表明,黄芪的生长及其根际微生物数量均受到干旱胁迫的影响,且适度干旱有助于提高黄芪根际细菌及放线菌的数量,从而改变根际微生物群落结构组成,促进黄芪地上生物量的积累。     

黄芪注射液的化学成分

采用正、反相硅胶柱层析从黄芪注射液原液中分离纯化出 14个化合物 ,经波谱分析鉴定了它们的结构。其中 6个为异黄酮化合物 ,分别是芒柄花素 (1) ,毛蕊异黄酮 (2 ) ,6″ O 乙酰基芒柄花苷 (3) ,芒柄花苷 (7) ,红车轴草异黄酮 7 O β D 吡喃葡萄糖 (12 ) ,毛蕊异黄酮 7 O β D 吡喃葡萄糖 (13) ;1个紫檀烷化合物 ,结构为 9,10 二甲氧基紫檀烷 3 O β D吡喃葡萄糖 (4) ;1个异黄烷化合物 ,结构为 2′ 羟基 3′ ,4′ 二甲氧基异黄烷 7 O β D 吡喃葡萄糖 (6 ) ;另外 6个为黄芪皂苷类化合物 ,分别是乙酰黄芪皂苷Ⅰ(5 ) ,黄芪皂苷Ⅰ (8) ,异黄芪皂苷Ⅰ (9) ,异黄芪皂苷Ⅱ (10 ) ,黄芪皂苷Ⅱ (11)和黄芪甲苷 (14)。其中化合物 3系首次从黄芪属植物中分离得到。     

肥料类型对盐碱地蒙古黄芪生长与光合特征及药材产量和品质的影响

以一年生蒙古黄芪种苗为材料,在盐碱地探究二年生蒙古黄芪根系产量和药效成分对不同肥料(海藻酸水溶肥、腐殖酸水溶肥、微生物菌剂生物肥、复合肥和有机肥)的响应以及其光合生理机制,为盐碱地蒙古黄芪的推广种植提供参考。结果显示:在盐碱地,微生物菌剂生物肥的施用对蒙古黄芪的抗逆性、光合作用效率、生长特性、根系产量及质量均无显著性影响;复合肥的施用显著促进了蒙古黄芪地上部分的生长,但对根系产量无显著影响,反而显著降低了其抗逆性、光合作用效率和药效成分;海藻酸水溶肥、腐殖酸水溶肥和有机肥的施用均显著提高了蒙古黄芪抗逆性、光合作用效率、地下部分的生长及产量、质量;施用有机肥的蒙古黄芪药材产量最高(7 046.2 kg·hm~(-2)),并与施用除腐殖酸水溶肥以外的其余处理差异显著,施用腐殖酸水溶肥和有机肥的蒙古黄芪药效成分含量最高并与其余施肥处理差异显著,它们的黄芪甲苷含量均达到0.13%以上,毛蕊异黄酮葡萄糖苷含量均达到0.06%以上。研究表明,在盐碱地蒙古黄芪栽培过程中,施用有机肥在保证蒙古黄芪药效成分较高的同时,还具有最高的药材产量,可认为是最佳肥料。     

Effects of MULTIFOLIATE-PINNA, AFILA, TENDRIL-LESS and UNIFOLIATA genes on leafblade architecture in Pisum sativum

In order to dissect the genetic regulation of leafblade morphogenesis, 16 genotypes of pea, constructed by combining the wild-type and mutant alleles of MFP, AF, TL and UNI genes, were quantitatively phenotyped. The morphological features of the three domains of leafblades of four genotypes, unknown earlier, were described. All the genotypes were found to differ in leafblade morphology. It was evident that MFP and TL functions acted as repressor of pinna ramification, in the distal domain. These functions, with and without interaction with UNI, also repressed the ramification of proximal pinnae in the absence of AF function. The expression of MFP and TL required UNI function. AF function was found to control leafblade architecture multifariously. The earlier identified role of AF as a repressor of UNI in the proximal domain was confirmed. Negative control of AF on the UNI-dependent pinna ramification in the distal domain was revealed. It was found that AF establishes a boundary between proximal and distal domains and activates formation of leaflet pinnae in the proximal domain.     

Presence of Rhizobium Etli bv . Phaseoli and Rhizobium Gallicum bv . Gallicum in Egyptian Soils

Seven bean rhizobial strains EBRI 2, 3, 21, 24, 26, 27 and 29 identified as Rhizobium etli, and EBRI 32 identified as Rhizobium gallicum, isolated from Egyptian soils and which nodulated Phaseolus vulgaris efficiently, were subjected to hybridization with a nifH probe in order to estimate the copy number of this gene. Seven strains (EBRI 2, 3, 21, 24, 26, 27 and 29) which were only able to nodulate Phaseolus vulgaris, contained three copies of the nifH gene, consistent with their identification as Rhizobium etli bv. phaseoli. Only one strain (EBRI 32) which nodulated both Phaseolus vulgaris and Leucaena leucocephala, had one copy of nifH gene. This confirmed the classification of this strain as Rhizobium gallicum bv. gallicum.     

Characterisation of cell wall polysaccharides, arabinogalactans-proteins (AGPs) and phenolics of Cola nitida, Cola acuminata and Garcinia kola seeds

Many Cola plant species are endemic to West and Central Africa. Cola acuminata and Cola nitida are used as masticatory when fresh, while the dried nuts are used for beverages and pharmaceutical purposes in Europe and North America. Garcinia kola seeds, that serve as a substitute for the true kola nuts, are used in African traditional medicine for the treatment of various diseases, including colic, headache and liver cirrhosis. Seeds extracts of G. kola are also known for their anti-inflammatory, antimicrobial and antiviral properties. To gain information on the chemical properties of the kolas, we have isolated and analyzed cell wall polysaccharides, arabinogalactan-proteins and phenolic substances from the seeds of the three kola species. The sugar composition of cell wall material of C. acuminata, C. nitida and G. kola revealed that Gal (up to 30%), Ara, GalA and Glc as the predominant monosaccharides, representing approximately 90% by mol of the total hydrolysable sugar present in this material. In Ammonium oxalate cell wall fraction, GalA was found to be the major sugar present in all kola species. In the alkali-soluble fraction, there were significant differences in the level of Glc and Gal. The level of Glc was high in C. acuminata and C. nitida while the level of Gal and Xyl were high in C. nitida and G. cola. Isolation and quantification of arabinogalactan-proteins demonstrate that G. kola seeds contained four to eight times more of these proteoglycans than the seeds of the other two species. Finally, analysis of soluble phenolic substances shows that caffeine and catechin were largely represented in C. acumina and C. nitida seeds, with caffeine accounting for 50% of all soluble phenolics. These findings indicate that the three Kola seeds are highly enriched in pectins and proteoglycans and that C. acuminata and C. nitida can be used as a possible source of caffeine and catechin.     

The phylogenetic placement of the Leucogastrales, including Mycolevis siccigleba (Cribbeaceae), in the Albatrellaceae using morphological and molecular data

The morphology of many hypogeous fungi converges on a homogeneous reduced form, suggesting that disparate lineages are subject to a uniform selection pressure. The primary goal of this study was to evaluate the morphology and infer the phylogeny of the Leucogastrales with Mycolevis siccigleba using a Bayesian methodology. A comprehensive morphological assessment was used for an a priori phylogenetic inference to guide the sequencing effort. All structures except spore ornamentation pointed to the Albatrellaceae as the most likely sister taxon. Polyporoletus sublividus, a close relative of Albatrellus, produces ornamented basidiospores with a similar structure to M. siccigleba basidiospores. The ITS from 30 taxa was used for the molecular phylogenetic analysis. P. sublividus was found sister to Mycolevis. Leucophleps spinispora and L. magnata formed a group sister to the Polyporoletus/Mycolevis group, whereas Leucogaster was polyphyletic with respect to the core of the Leucogastrales and sister to A. caeruleoporus. This relationship was expected as previously undescribed chlamydospores produced by members of Albatrellus had a similar morphology to the basidiospores of L. rubescens.     

苏云金芽胞杆菌幕虫亚种晶胞粘连现象与晶体蛋白基因cry26Aa所在质粒有关

苏云金芽胞杆菌幕虫亚种T02菌株的伴胞晶体在芽胞外壁内侧形成,呈现晶胞粘连的现象。在此菌株中克隆了cry26Aa和cry28Aa两个基因,并对晶胞粘连现象与质粒的相关性做了系统研究。通过消除幕虫亚种T02菌株的质粒,得到了仅消除cry26Aa所在质粒的菌株BMB1151和无质粒的菌株BMB1152。通过穿梭载体将cry26Aa和cry28Aa两个基因分别和同时转化无质粒突变株BMB1152并表达,形成的晶体与芽胞独立存在不能粘连,表明在幕虫亚种染色体背景下仅仅cry的表达不能形成晶胞粘连现象,从而推断晶胞粘连现象可能与幕虫亚种两个基因所在的质粒有关;进一步的研究发现将cry26Aa在仅消除cry26Aa所在质粒的突变株BMB1151中表达,形成的晶体与芽胞也分别独立存在不能粘连,从而进一步推断幕虫亚种晶胞粘连现象与cry26Aa所在质粒有关。     

Genome Analysis inNeurospora crassa;Cloning of Four Lociarginine-1(arg-1),methionine-6(met-6),unknown-7(un-7), andribosome production-1(rip-1) and Associated Chromosome Walking

We have cloned fourNeurospora crassagenes by complementation analysis. Cloned genes include thearginine-1(arg-1),methionine-6(met-6),unknown-7(un-7), andribosome production-1(rip-1) loci. Chromosome walks were initiated in ordered cosmid libraries from the cloned loci. A total of about 700 kb of theNeurosporagenome is covered in these walks.     

转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响

【目的】为探究转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响。【方法】以转Cry1Ac/1Ab基因棉与其亲本常规棉为实验材料,利用取食不同棉花品种叶片的棉铃虫饲喂异色瓢虫幼虫。【结果】与常规亲本棉相比,取食饲喂转基因棉花叶片的初孵棉铃虫幼虫的异色瓢虫幼虫从1龄发育至化蛹期时间延长0.77 d,但差异不显著;除1龄幼虫体重增加(0.0773 mg)外,其余各龄期幼虫体重均有所下降,但差异均不显著;异色瓢虫1、2、3、4龄幼虫对初孵棉铃虫捕食量均随棉铃虫密度的增加而增加,捕食功能反应均符合HollingⅡ圆盘方程。【结论】转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育无显著影响,饲喂取食转Cry1Ac/1Ab基因棉花的棉铃虫对异色瓢虫捕食功能无显著差异。     

巴西橡胶树HbSUT3和HbSUT5 mRNA在嫩茎和中脉中的原位杂交分析

为研究巴西橡胶树(Hevea brasiliensis)中HbSUT3和HbSUT5基因的功能,采用地高辛标记的RNA探针与橡胶树嫩茎和中脉两种组织切片分别进行RNA原位杂交,对这2种SUT基因在组织中的表达区域与表达特点进行了分析。结果表明,在橡胶树嫩茎中,两个SUT基因主要在树皮的韧皮部和皮层细胞中表达;在中脉中,两个SUT基因在除木质部导管系统外的其它部位均有表达;HbSUT3基因在嫩茎和中脉中的表达量相近,而HbSUT5基因在嫩茎中的表达量远高于中脉。这些揭示HbSUT3和HbSUT5基因可能广泛参与韧皮部装载、蔗糖运输与库细胞供给等活动,同时两个SUT基因也存在功能分化。     

The phylogenetic placement of Ostropales within Lecanoromycetes (Ascomycota) revisited

Results of molecular studies regarding the phylogenetic placement of the order Ostropales and related taxa within Lecanoromycetes were thus far inconclusive. Some analyses placed the order as sister to the rest of Lecanoromycetes, while others inferred a position nested within Lecanoromycetes. We assembled a data set of 101 species including sequences from nuLSU rDNA, mtSSU rDNA, and the nuclear protein-coding RPB1 for each species to examine the cause of incongruencies in previously published phylogenies. MP, minimum evolution, and Bayesian analyses were performed using the combined three-region data set and the single-gene data sets. The position of Ostropales nested in Lecanoromycetes is confirmed in all single-gene and concatenated analyses, and a placement as sister to the rest of Lecanoromycetes is significantly rejected using two independent methods of alternative topology testing. Acarosporales and related taxa (Acarosporaceae group) are basal in Lecanoromycetes. However, if the these basal taxa are excluded from the analyses, Ostropales appear to be sister to the rest of Lecanoromycetes, suggesting different ingroup rooting as the cause for deviating topologies in previously published phylogenies.