芒果褐色蒂腐病菌(Phomopsis mangiferae)生物学特性研究

从广西芒果病区分离出芒果褐色蒂腐病菌 (Phomopsismangiferae) ,对其生物学特性进行的研究结果表明 ,该病菌的最适生长温度为 2 5～ 31℃ ;最适生长 pH值为 6 .0～ 6 .5 ;不同光环境对分生孢子器形成的影响较大 ,其中黑光最利于分生孢子器的形成 ;多菌灵对该病菌的室内抑制作用最强     

中药提取物对黄芪根腐病菌的抑制效果

打破了传统的化学药剂(特别是农药)防治黄芪根腐病菌的局限,以发展绿色防治中药材病害为前提,采用蛇床子、知母的提取液制备含药培养基,并以灭菌水作为对照,分别接种黄芪根腐病菌,探讨这两种中药对黄芪根腐病菌—尖孢镰刀菌(Fusarium oxysporum)的抑制作用。研究结果表明,2种中药提取物对抑制黄芪根腐病菌均有不同程度的影响,实验结果表明,无论从药剂类型还是药剂浓度来看,蛇床子防治黄芪根腐病菌的效果最佳,具有显著水平,其最高抑制率为96.13%。     

几种野生植物提取物抑菌作用研究

本文以乙醇为溶剂,分别提取了瓦松、泽漆及一组中草药配方的有效成分;室内测定了三种提取液对5种植物病原菌(棉花枯萎病菌Fusarium oxysporum f.sp.vasinfectum;小麦赤霉病菌Fusarium graminearum Schw;西瓜枯萎病菌Fusarium oxysporum f.sp.niveum;仙人掌软腐病菌Erwinia chrysanthemi pv.chrysanthemi;魔芋软腐病菌Erwiniacarotovora pv.carotovora)的抑菌作用.结果表明:三种提取物对镰刀菌均有不同程度的抑制作用,且三种提取物的抑菌效果差异显著,其中瓦松的抑菌效果最强.当在50 mL培养基中加入5mL不同提取液时,瓦松对不同镰刀菌的相对抑制率为91.39%～100%;中草药配方提取液对不同镰刀菌的相对抑制率分别为41.11%～85.37%;而泽漆提取液对镰刀菌的相对抑制率仅为12.86%～21.23%;当在50 mL培养基中加入提取液体积降低为2 mL、1 mL、0.5mL时,三种提取液对三种镰刀菌的抑制效果骤然下降,但下降的梯度不一.对大白菜软腐病菌与魔芋软腐病菌而言也是瓦松的抑菌效果最强,中草药配方次之,泽漆的抑制效果最差.     

芒果、香蕉采后病害生物防治的研究进展

芒果、香蕉采后主要病害为炭疽病、蒂腐病、冠腐病、黑腐病、黑星病.生物防治是当前芒果、香蕉采后病害控制的重要研究方向.概述了生物防治芒果、香蕉采后病害的方法,包括诱抗剂、植物提取物、拮抗微生物在芒果、香蕉采后病害防治上的研究与应用.     

林下参内生球毛壳菌FS-01对人参病原真菌的抑制作用

为探究林下参内生真菌球毛壳菌(Chaetomium globosum)FS-01菌株对人参病原菌的抑菌作用,该研究在实验室条件下,测定了FS-01菌株菌丝、发酵液和孢子悬浮液对人参黑斑病菌(Alternaria panax)、人参菌核病菌(Sclerotinia schinseng)、人参灰霉病菌(Botrytis cinerea)、人参立枯病菌(Rhizoctonia solani)、人参根腐病菌(Fusarium solani)5种人参病原菌的抑制作用。结果表明:内生真菌球毛壳菌FS-01对5种病原菌均有抑制作用,其中,对人参黑斑病菌的抑制作用最高,为30.80%,其次是人参立枯病菌、人参菌核病菌、人参根腐病菌和人参灰霉病菌; 发酵液抑菌实验结果表明,在加入内生真菌球毛壳菌FS-01菌株发酵液的PDA培养基上,对人参灰霉病菌的抑制作用最高,为82.09%,其次是人参菌核病菌、人参黑斑病菌、人参立枯病菌和人参根腐病菌; 孢子抑菌实验结果表明,在加入内生真菌球毛壳菌FS-01菌株孢子悬浮液的PDA培养基上,对人参黑斑病菌的抑制作用最高,为83.72%,其次是人参灰霉病菌、人参立枯病菌、人参菌核病菌和人参根腐病菌。综上结果认为,内生真菌球毛壳菌FS-01菌株对人参病原菌均有很高的抑菌作用,可作为人参病原菌的生防菌株资源。     

迷迭香酸对几种植物病原真菌的抗菌活性*

研究了迷迭香酸对不同植物病原真菌菌丝生长和孢子萌发的抑制活性。试验结果表明,迷迭香酸对供试的8种植物病原真菌菌丝生长均有抑制作用,其中对番茄灰霉病菌、芒果灰斑病菌、柑桔青霉和梨黑斑病菌抑制作用较强,EC50分别为615．04μg/mL、698．23μg/mL、714．50μg/mL和809．10μg/mL;对杉木猝倒病菌和苹果树腐烂病菌抑制作用次之,EC50分别为1039．92μg／mL和1044．72μg/mL;对松枯梢病菌和种实霉烂病菌的抑制作用较弱,EC50分别为1256．90μg/mL和1270．87μg/mL。迷迭香酸对供试的6种植物病原真菌孢子萌发也有明显的抑制作用,EC50大致在400～700μg/mL范围,其中对梨黑斑病菌孢子萌发抑制作用最强,EC50为395．37μg/mL。     

龙柏乙酸乙酯萃取物抑菌活性成分的分离与鉴定

采用活性追踪法和柱层析法,以苹果腐烂病菌、葡萄白腐病菌等作为供试菌种,从龙柏乙醇提取物的乙酸乙酯萃取物中分离得到抑菌活性成分.结果表明,在供试浓度为2 mg/mL时,龙柏乙酸乙酯萃取物对6种植物病菌均有一定的抑制作用,其中对苹果腐烂病菌和葡萄白腐病菌抑菌活性最好,抑菌率分别为83.06％和78.87％.其活性成份桧脂素对苹果腐烂病菌、葡萄白腐病菌、小麦赤霉病菌、葡萄黑痘病菌、苹果轮纹病菌和黄瓜枯萎病菌的EC50分别为0.38、0.18、0.47、0.59、0.70 mg/mL和1.94 mg/mL.     

烟草根黑腐病拮抗内生细菌的筛选及其抑菌作用

【目的】从烟草根、茎中分离获得对烟草根黑腐病菌(Thielaviopsis basicola)有较好控病作用的内生细菌。【方法】采用平板对峙培养,测定分离获得的306个内生细菌对烟草根黑腐病菌的抑制作用;通过菌株形态特征、生理生化特性及16S rDNA序列对菌株进行分类鉴定。【结果】筛选获得6个菌株对烟草根黑腐病菌有较强拮抗作用,室内测定其对病原菌的抑菌带宽达6.5 mm-11.0 mm,温室控病效果达11.9%-77.1%,其中来自茎部的内生细菌T295菌株对烟草根黑腐病的防效达77.1%;无菌滤液实验表明,拮抗内生细菌T295无菌滤液在实验浓度范围内对病菌菌丝生长、孢子萌发有较好地抑制作用。【结论】菌株T295对烟草根黑腐病具有较好的防治作用,经鉴定为枯草芽孢杆菌(Bacillussubtilis)。     

抑制水稻细菌性条斑病菌的没食子酸分离及其对水稻细菌性条斑病的防治作用（英文）

通过液—液萃取、硅胶和凝胶柱层析法,从佛甲草(Sedum lineare)分离出一种可以抑制水稻细菌性条斑病菌(Xanthomonas oryzae pv.oryzicola,Xoc)生长的单体化合物,经质谱分析,确定该化合物为没食子酸(gallic acid,GA)。在30 mg·mL~(-1)浓度下,GA能抑制一些植物病原细菌如桃细菌性穿孔病菌(X.campestris pv.pruni)、水稻细菌性条斑病菌(X.oryzae pv.oryzicola)、水稻白叶枯病菌(X.oryzae pv.oryzae)、柑橘溃疡病菌(X.axonopodis pv.citri)、大豆细菌性斑点病菌(Pseudomonas syringae pv.glycinea)、番茄细菌性斑点病菌(P.syringae pv.tomato)和胡萝卜软腐果胶杆菌(Pectobacterium carotovora subsp.carotovora)的生长;GA还对11种植物病原真菌如烟草疫霉(Phytophthora nicotianae)、指状青霉(Penicillium digitatum)、滇刺枣褐腐病菌(Streptobotrys streptothrix)、瓜果腐霉(Pythium aphanidermatum)、芒果拟盘多毛孢(Pestalotiopsis mangiferae)、新月弯孢霉(Curvularia lunata)、立枯丝核菌(Rhizoctonia solani)、(Fusarium oxysporum f.sp.niverum)、西瓜专化型尖孢镰刀菌(F.oxysporum f.sp.nicotianae)、番茄灰霉病菌(Botrytis cinerea)和齐整小核菌(Sclerotium rolfsii)的生长具有一定的抑制作用。在300 mg·mL~(-1)浓度下,GA对水稻细菌性条斑病的田间防治效果达到64.62%。该研究结果表明没食子酸具有开发成为一种防治水稻细菌性条斑病的杀菌剂的潜力。     

抑制水稻细菌性条斑病菌的没食子酸分离及其对水稻细菌性条斑病的防治作用

通过液—液萃取、硅胶和凝胶柱层析法,从佛甲草(Sedum lineare)分离出一种可以抑制水稻细菌性条斑病菌(Xanthomonas oryzae pv.oryzicola,Xoc)生长的单体化合物,经质谱分析,确定该化合物为没食子酸(gallic acid,GA)。在30 mg·m L-1浓度下,GA能抑制一些植物病原细菌如桃细菌性穿孔病菌(X.campestris pv.pruni)、水稻细菌性条斑病菌(X.oryzae pv.oryzicola)、水稻白叶枯病菌(X.oryzae pv.oryzae)、柑橘溃疡病菌(X.axonopodis pv.citri)、大豆细菌性斑点病菌(Pseudomonas syringae pv.glycinea)、番茄细菌性斑点病菌(P.syringae pv.tomato)和胡萝卜软腐果胶杆菌(Pectobacterium carotovora subsp.carotovora)的生长;GA还对11种植物病原真菌如烟草疫霉(Phytophthora nicotianae)、指状青霉(Penicillium digitatum)、滇刺枣褐腐病菌(Streptobotrys streptothrix)、瓜果腐霉(Pythium aphanidermatum)、芒果拟盘多毛孢(Pestalotiopsis mangiferae)、新月弯孢霉(Curvularia lunata)、立枯丝核菌(Rhizoctonia solani)、(Fusarium oxysporum f.sp.niverum)、西瓜专化型尖孢镰刀菌(F.oxysporum f.sp.nicotianae)、番茄灰霉病菌(Botrytis cinerea)和齐整小核菌(Sclerotium rolfsii)的生长具有一定的抑制作用。在300 mg·m L-1浓度下,GA对水稻细菌性条斑病的田间防治效果达到64.62%。该研究结果表明没食子酸具有开发成为一种防治水稻细菌性条斑病的杀菌剂的潜力。     

西沙群岛的腐生半知菌

Fourteen species of saprotrophic fungi isolated from various substrates from Xisha Islands are reported, including a new record species-Curvlaria tuberculata Jain. The others are: Alternaria alternata (Fr.) Keissler. A. phragmospora van. Emden, Aspergillus niger van. Tiegh., Cladosporium arysporum Berk. & Curt., C sphaerospormum Penz., Curvularia affinis Boedijn, C. geniculata (Tracy & Earle) Boedijn, C. lunata (Walk.) Boedijn, Exserohilium turcicum (Pass.) Leonard & Suggs.,Humicola grisea Traaen, Botryodip…     

Investigation on the spectrum-effect relationships of EtOAc extract from Radix Isatidis based on HPLC fingerprints and microcalorimetry

This work investigated the spectrum-effect relationships between HPLC fingerprints and the anti-bacterial activities of EtOAc extracts from Radix Isatidis. Fingerprints of EtOAc extracts of Radix Isatidis from various sources were established by a High-Performance Liquid Chromatography. The process of Escherichia coli (E. coli) growth affected by EtOAc extracts was monitored using a Thermal Activity Monitor (TAM) Air Isothermal Calorimeter by microcalorimetry. By analyzing the power-time curves, quantitative parameters, such as growth rate constant k, maximum heat-production rate P(m), appearance time t and total heat-production Q were obtained to characterize the interactions of E. coli and the EtOAc extracts from Radix Isatidis. The HPLC fingerprints were investigated using hierarchical clustering analysis. The main thermo-kinetic parameters from the power-time curves were analyzed using principal component analysis. The spectrum-effect relationships between the HPLC fingerprints and anti-bacterial activities were analyzed with multivariant correlation analysis. Close correlation existed between the spectrum-effect relationships of the EtOAc extracts. Salicylic acid in the HPLC fingerprints might be one of the anti-bacterial components. This work provides a general model of the combination of HPLC and microcalorimetry to study the spectrum-effect relationships of EtOAc extracts from Radix Isatidis, which can be used to search for principal components of Radix Isatidis on bioactivity.     

天然药物对血链球菌生长和产酸影响的体外研究

目的：通过研究不同天然药物对血链球菌生长及产酸的影响,为今后筛选出能有效调理口腔菌群生态平衡的药物奠定基础。方法：选用变形链球菌SB179作为实验菌株,测定川芎,血藤,五倍子等11种天然药物的最低抑菌浓度MIC,再以低于MIC的4个浓度配制含药的TPY液体培养基,调定其初始pH为7．4,接种血链球菌,厌氧培养后测定其终末pH,结果：当药物浓度低于或等于8．000mg/ml时,各天然药物对血链球菌的生长均有一定的抑制作用,且以五倍子作用较强,槟榔,茶多酚,蜂房,大黄,三七,血藤,白芷对血链球菌的产酸具有一定的抑制能力,而黄芩,川芎,五倍子和儿茶没有明显的抑制作用,结论：槟榔,茶多酚,蜂房,大黄,三七,血藤和白芷对血链球菌的生长和产酸都有一定的抑制作用.     

天然药物对唾液链球菌生长与产酸影响的体外研究

目的：通过研究不同天然药物对唾液链球菌生长及产酸的影响,为今后筛选出能有效调理口腔菌群生态平衡的药物奠定基础,方法：选用唾液链球菌SS196作为实验菌株,测定川芎,血藤,五倍子等11种天然药物的最低抑菌浓度MIC,再以低于MIC的4个浓度梯度配制含药的TPY液体培养基,调定其初始pH为7．4,接种唾液链球菌,厌氧培养后测定其终末pH,结果：当药物浓度低于或等于8．00mg/ml时,除槟榔,蜂房,三七外,其他药物对唾液链球菌的生长都有一定的抑制作用,且以大黄,五倍子和黄芩较强,槟榔,茶多酚,大黄,蜂房,黄芩,三七,五倍子和儿茶对唾液链球菌的产酸具有一定的抑制能力,而白芷,川芎和血藤没有明显的抑制能力,结论：茶多酚,大黄,黄芩,五倍子和儿茶对唾液链球菌的生长和产酸都有一定的抑制作用。     

Serum response factor mRNA induction in the hypertrophying chicken patagialis muscle

Gene expression inthe stretched chicken patagialis (Pat) muscle has not been extensivelyexamined. This study's purpose was to determine the Pat muscle'sexpression pattern of serum response factor (SRF), skeletal -actin,and MyoD mRNAs after 3 days (onset of stretch), 6 days (end of firstweek of rapid growth), and 14 days (slowed rate of stretch-inducedgrowth) of stretch. SRF mRNA demonstrated two species (B1 and B2), withB2 being more prevalent in the predominantly fast-twitch Pat muscle,compared with the slow-tonic muscle. Stretch overload increased B1 andB2 SRF mRNA concentrations, and the increase in B1 SRF mRNAconcentration was greater at day 6 compared with days 3 or14. MyoD mRNA concentration wasgreater in 3-day-stretched Pat muscles, compared withdays 6 or14 . Skeletal -actin mRNAconcentration was not changed during the study. Gel mobility shiftassays demonstrated that SRF binding with serum response element 1 ofthe skeletal -actin promoter had no altered binding patterns from6-day-stretched Pat nuclear extracts. It appears that SRF and MyoDmRNAs are induced in the stretch-overloaded Pat muscle but at differenttime points.

     

The 3′ Overhangs at Tetrahymena thermophila Telomeres Are Packaged by Four Proteins,Pot1a,Tpt1, Pat1, and Pat2

Although studies with the ciliate Tetrahymena thermophila have played a central role in advancing our understanding of telomere biology and telomerase mechanisms and composition, the full complement of Tetrahymena telomere proteins has not yet been identified. Previously, we demonstrated that in Tetrahymena, the telomeric 3′ overhang is protected by a three-protein complex composed of Pot1a, Tpt1, and Pat1. Here we show that Tpt1 and Pat1 associate with a fourth protein, Pat2 (Pot1 associated Tetrahymena 2). Mass spectrometry of proteins copurifying with Pat1 or Tpt1 identified peptides from Pat2, Pot1a, Tpt1, and Pat1. The lack of other proteins copurifying with Pat1 or Tpt1 implies that the overhang is protected by a four-protein Pot1a-Tpt1-Pat1-Pat2 complex. We verified that Pat2 localizes to telomeres, but we were unable to detect direct binding to telomeric DNA. Cells depleted of Pat2 continue to divide, but the telomeres exhibit gradual shortening. The lack of growth arrest indicates that, in contrast to Pot1a and Tpt1, Pat2 is not required for the sequestration of the telomere from the DNA repair machinery. Instead, Pat2 is needed to regulate telomere length, most likely by acting in conjunction with Pat1 to allow telomerase access to the telomere.     

The Pot1a-associated proteins Tpt1 and Pat1 coordinate telomere protection and length regulation in Tetrahymena

We have identified two new telomere proteins, Tpt1 and Pat1, from the ciliate Tetrahymena thermophila. Although Tetrahymena telomerase is well characterized, only one telomere protein had previously been identified. This was the G-overhang binding-protein Pot1a. Tpt1 and Pat1 were isolated as Pot1a binding partners and shown to localize to telomeres. As Tpt1 and Pat1 were both found to be essential, conditional cell lines were generated to explore their function. Tpt1 depletion caused a rapid growth arrest and telomere elongation in the absence of cell division. The phenotype was similar to that seen after Pot1a depletion suggesting that Tpt1 and Pot1a function together to regulate telomere length and prevent telomere deprotection. In contrast, Pat1 depletion had a modest effect on cell growth but caused progressive telomere shortening similar to that observed upon TERT depletion. Thus Pat1 appears to be needed for telomerase to maintain the chromosome terminus. Analysis of Pot1a-Tpt1-Pat1 complex formation using purified proteins indicated that Tpt1 interacts directly with Pot1a while Pat1 interacts with Tpt1. Our results indicate that Tpt1 is the Tetrahymena equivalent of mammalian TPP1, Schizosaccharomyces pombe Tpz1, and Oxytricha nova TEBPβ.     

Diauxic shift-dependent relocalization of decapping activators Dhh1 and Pat1 to polysomal complexes

Dhh1 and Pat1 in yeast are mRNA decapping activators/translational repressors thought to play key roles in the transition of mRNAs from translation to degradation. However, little is known about the physical and functional relationships between these proteins and the translation machinery. We describe a previously unknown type of diauxic shift-dependent modulation of the intracellular locations of Dhh1 and Pat1. Like the formation of P bodies, this phenomenon changes the spatial relationship between components involved in translation and mRNA degradation. We report significant spatial separation of Dhh1 and Pat1 from ribosomes in exponentially growing cells. Moreover, biochemical analyses reveal that these proteins are excluded from polysomal complexes in exponentially growing cells, indicating that they may not be associated with active states of the translation machinery. In contrast, under diauxic growth shift conditions, Dhh1 and Pat1 are found to co-localize with polysomal complexes. This work suggests that Dhh1 and Pat1 functions are modulated by a re-localization mechanism that involves eIF4A. Pull-down experiments reveal that the intracellular binding partners of Dhh1 and Pat1 change as cells undergo the diauxic growth shift. This reveals a new dimension to the relationship between translation activity and interactions between mRNA, the translation machinery and decapping activator proteins.     

当归水提液和醇提液体外抗脂质过氧化和红细胞溶血作用

研究当归水提液和醇提液对小鼠肝组织自发性过氧化酯质分解产物丙二醛（malondialdehyde,MDA）的生成和对红细胞膜脂质过氧化及红细胞溶血作用的影响。采用TBA比色法测定肝组织匀浆MDA生成,分光光度法测定过氧化氢诱导红细胞膜脂质过氧化和溶血。实验分为空白组、对照组、加药组。加药组分为25、50、100和200mg/mL四个浓度组。当归水提液和醇提液均在25～200mg／mL的浓度范围内,能够明显抑制小鼠肝组织匀浆自发性MDA的生成,具有抑制过氧化氢诱导红细胞膜脂质过氧化和溶血的作用,抑制效果随当归水提液和醇提液浓度的增大而逐渐增强,抑制率与药物浓度成良好的量效关系。当归水提液和醇提液具有抗脂质过氧化和红细胞溶血的作用。