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1.
黄蓝状菌一种几丁质酶的纯化、性质及抗菌活性 总被引：5，自引：0，他引：5
黄蓝状菌Talaromyces flavus在SMCS液体培养基中置于恒温摇床(200r/min,27．5℃)上培养13d，诱导产生大量的几丁质酶。培养滤液经硫酸铵分级沉淀，DEAE-Sepharose Fast Flow阴离子交换层析、Phenyl-Sepharose Fast Flow疏水层析、Sephacvl S—100分子筛层析得到了凝肢电泳(SDS-PAGE)谱带单一的几丁质酶，其分子量为41kD。其最适反应温度为50℃，最适pH值是5。Mn^2 对其有明显的激活作用，Cu^2 、Fe^2 对其有强烈的抑制作用。抗菌活性显示，其对供试病原菌具有明显的抑菌作用。 相似文献
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桑粒肩天牛纤维素酶的性质研究 总被引：15，自引：1，他引：15
桑粒肩天牛（ＡｐｒｉｏｎａｇｅｒｍａｒｉＨｏｐｅ）幼虫肠道内有完整的纤维素酶系，其中以内切－β－１，４－葡聚糖酶（Ｃｘ酶）活性最强、β－１，４－葡萄糖苷酶次之，外切－β－１，４－葡聚糖酶（Ｃ１酶）最弱、测定了Ｃｘ酶和β－１，４－葡萄糖苷酶的动力学特性以及金属离子对酶活性的影响。二者的最适作用ＰＨ值分别为４．４和５．６；最适作用温区分别为３０℃—４５℃和４５℃—５０℃；Ｃｘ酶经５０℃处理２ｈ酶活性仅下降１８．８％，而β－葡萄糖苷酶活性完全丧失。９种金属离子对纤维素酶都无明显激活作用，相反，除Ｈｇ＋＋和Ｐｂ＋＋对酶活性有强烈抑制作用外，Ｍｎ＋＋和Ｃｕ＋＋即使在０．００５ｍｏｌ／Ｌ低浓度下，对酶活性也有明显的抑制作用，这对今后开发酶抑制剂用于防治天牛等蛀干害虫，具有重要意义。 相似文献
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以长白山刺楸人工林选择的刺楸优良个体休眠枝条为试验材料，进行刺楸组培快繁各个阶段最适培养基的筛选。结果表明，刺楸组织培养的最适外置体为叶柄；愈伤组织诱导的最适培养基为WPM＋2，4－D0．50 mg／L＋NAA0．1 mg／L，诱导率96％；愈伤组织诱导再分化最适培养基为WPM＋KT2．0 mg／L＋6－BA0．50 mg／L＋NAA 0．1 mg／L，分化率达82％；不定芽继代培养最适培养基为WPM＋KT1．0 mg／L＋6－BA0．50 mg／L＋NAA 0．1 mg／L，增殖系数为3．69；不定芽生根培养最适培养基为WPM＋NAA 0．5 mg／L，生根率达到85％。 相似文献
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杉木幼茎离体培养与快繁体系的建立 总被引：1，自引：0，他引：1
应用正交设计法研究了以杉木幼茎为外植体的离体培养与快繁技术,建立了杉木高频离体再生体系,试验结果表明：愈伤诱导的最适培养基为2／3WPM＋6-BA0．5mg／l＋IBA2．0mg/l＋2,4-D0．8mg/l;芽分化的最适培养基为：WPM＋6-BA1．5mg／l＋IBA2．0mg／l＋2,4-D1．2mg／l;生根的最适培养基为1／2WPM＋6-BA0．5mg／l＋IBA1．0mg／l＋IAA1．2mg／l;杉木移栽的最适培养物是草皮土与泥炭土体积比为1：1的混合土。 相似文献
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以柠檬桉优株带芽茎段为外植体进行组培快繁技术体系研究。结果表明：晴天＋流水冲洗1h＋0．1％HgCl2（3＋4）min为柠檬桉的最佳外植体采集处理方案。培养基添加VC20．0mg.L-1或PVP2．0g.L-1是褐变控制的有效措施,不同防褐化剂的效果为：PVP=VC〉AC〉DTT〉CA。改良MS＋6-BA1．0mg·L-1＋KT0．2mg·L-1＋NAA0．05mg.L-1是柠檬桉扩繁增殖的最适培养基;改良MS＋6-BA0．5mg.L-1＋NAA0．1mg.L-1是柠檬桉壮苗增殖的最适培养基。自然光培养,光照强度3000～3500Lux是柠檬桉增殖培养的最适光照条件。 相似文献
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石斛兰组织培养及快繁技术研究 总被引：21，自引：0，他引：21
对两种石斛兰属植物进行了茎尖培养和快繁技术研究,结果表明，在不同激素配比的MS培养基中，MS＋BA0．5＋NAA0．5＋CH有利于石斛兰的原球茎球状体（PLB）分化成幼苗，在MS＋BA2．0＋NAA0．5＋CH中石斛兰的原球茎球状体（PLB）易保持原形态增殖，1／2MS＋IBA0．3活性炭能促进根的生成和生长。 相似文献
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对西南桦不同种源优选株系萌芽条离体快繁技术的初代培养、增殖培养、生根培养和移栽等方面进行研究。结果表明,初代培养最适培养基为改良MS＋6-BA3．0mg／L＋NAA0．25mg／L＋光照14h／d,芽体分化率最高达57．8％;最适增殖培养基为改良MS＋6-BA2．5mg／L＋NAA0．25mg／L＋糖35g／L;生根培养基为1／2改良MS＋IBA1．0mg／L＋NAA0．1mg／L＋IAA0．10rag／L;组培苗移栽基质为70％泥炭土＋30％红心土。 相似文献
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现代郁金香离体培养与快速繁殖 总被引：2，自引：2，他引：0
以现代郁金香的内层鳞片、幼茎和茎尖为外植体进行了离体培养与快速繁殖试验,筛选出最佳培养基;（1）诱导鳞片产生丛芽为MS＋0．4～1．0mg／LBA＋0．4mg／LNAA;（2）茎尖诱导培养为MS＋2mg／LBA＋0．1mg／LNAA;（3）茎段诱导培养为MS＋1．0mg／LBA＋0．2mg／LNAA）（4）丛芽增殖培养为MS＋0．4mg／LBA＋0．2mg／LNAA和MS＋0．4mg／LBA＋0．2mg／LIAA;（5）生根诱导培养为1／2MS＋0．4mg／LKT和0．1～1．0mg／LNAA。 相似文献
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The crude extracts obtained from the leaves of Pistacia vera, Pistacia terebinthus and Pistacia lentiscus were tested for antifungal activities against three pathogenic agricultural fungi, Phythium ultimum, Rhizoctania solani and Fusarium sambucinum. The extracts significantly inhibited the growth of P. ultimum and R. solani. However, the antifungal activity was not observed against F. sambucinum. 相似文献
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Acaciaside A and B, two acylated bisglycoside saponins originally isolated from the funicles of Acacia auriculiformis, are known to have antihelminthic activity. Their antifungal and antibacterial activities were investigated. Complete inhibition of conidial germination of Aspergillus ochraceous and Curvularia lunata was recorded at 300 microg/ml or less whereas to inhibit the growth of Bacillus megaterium, Salmonella typhimurium and Pseudomonas aeruginosa 700 microg/ml or higher concentrations of the mixture was required. Two catabolic enzymes, phosphofructokinase and isocitrate dehydrogenase, responded differentially in fungi and bacteria against sublethal concentrations of the compound when assayed from their cell free extracts. An increased specific activity of the enzymes in bacteria and a decrease activity in fungi indicate a possible different mechanism of inhibition of saponins on the organisms tested. 相似文献
13.
为筛选出新的对绵腐卧孔菌、绿色木霉和彩绒革盖菌3种常见木材真菌有效的杀菌剂,采用菌丝生长速率法,测定了山苍子油主成分及其衍生物共10种化合物对这3种常见木材真菌的抑制率,建立毒力方程并分析其活性。结果表明:10种化合物对3种常见木材真菌的生长均表现出一定的抑制作用,而且随着浓度的升高,抑制作用增强;通过10种化合物对3种常见木材真菌的毒力回归分析,并与三唑酮相比较,依次筛选出对绵腐卧孔菌、绿色木霉和彩绒革盖菌的抑制作用最强的分别为柠檬醛1,2-丙二醇缩醛、β-紫罗兰酮和鸢尾酮,其半数有效抑制质量浓度(EC50)依次分别为18.69、23.50和32.21 mg/L。3种真菌分别经柠檬醛1,2-丙二醇缩醛、β-紫罗兰酮和鸢尾酮处理后,菌体细胞膜的相对渗透率发生变化,表明山苍子油活性成分的木材防腐作用与菌体细胞膜遭破坏有关。 相似文献
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本研究以木材蓝变生物控制菌康氏木霉(6111-ET)为供试菌株进行胞外几丁质酶纯化和特性的研究.将液态PDA培养基中的康氏木霉(Trichoderma koningii)置于恒温播床(200 r/min,28℃)培养10天.培养滤液经过硫酸铵分级沉淀、Q-HP强阴离子交换柱层析、Phenyl-Sepharose疏水层析... 相似文献
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Gry Alfredsen Halvor Solheim Rune Slimestad 《European Journal of Forest Research》2008,127(5):387-393
The inhibitory effect of methanol bark extracts from six deciduous and three coniferous European tree species were bioassayed
against eight fungi from the different damage categories, brown rot, white rot, canker and blue-stain. This is the first report
providing data on the antifungal activity of several Europaen tree species against fungi within these damage categories. Generally
the decay fungi were more inhibited by the bark extracts than the blue-stain fungi, while the lowest inhibition was found
among the cancer fungi. The main pattern found between the fungal groups in relation to the bark extracts in this study is
believed to be caused by the route of ingress. Acer platanoides bark extract proved to be the most efficient bark extract tested, significantly reducing the growth rate of all tested fungi.
Betula pubescens bark extract generally gave the weakest reduction in growth rate. In this study, the conifer bark extracts were in general
more active against the canker and blue stain ascomycete fungi than the deciduous trees extracts. 相似文献
16.
Chia-Che Wu Chi-Lin Wu Shou-Ling Huang Hui-Ting Chang 《Wood Science and Technology》2012,46(4):737-747
Wood-rotting fungi lead to great economic losses of lignocellulosic materials. The influence of extractives on the decay resistance of Michelia formosana wood and the antifungal activities of heartwood extract and its constituent against wood-rotting fungi were evaluated. Results revealed that extractives had a strong influence on the decay resistance of M. formosana heartwood. The unextracted heartwood block was resistant to fungi, while the extracted heartwood block was not. Antifungal activities of ethanolic extract from heartwood were assessed; results revealed that the ethanolic extract possessed good antifungal activity against wood-rotting fungi. The ethanolic extract was further separated into four fractions including n-hexane-soluble fraction, ethyl acetate-soluble fraction, n-butanol-soluble fraction, and water-soluble fraction. Among these fractions, the n-hexane-soluble fraction exhibited the best antifungal ability. An alkaloid, liriodenine, was isolated from the active n-hexane-soluble fraction. IC50 values of liriodenine against the white-rot fungi Lenzites betulina and Trametes versicolor were 0.76 and 3.50?μg/mL, respectively. IC50 values of liriodenine against the brown-rot fungi Laetiporus sulphureus, Gloeophyllum trabeum, and Fomitopsis pinicola were all lower than 2.0?μg/mL. Results indicated that liriodenine exhibited a broad spectrum of antifungal activity and great potential to develop as an environmentally benign fungicide for the preservation of lignocellulosic materials. 相似文献
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Bioassays were performed to determine the antifungal and insecticidal activity of clove essential oil (EO), several botanical compounds (eugenol, carvacrol, allylisothiocyanate (AITC) and ethyl formate (EtF)) against mycotoxigenic fungi (Aspergillus westerdijkiae and Fusarium graminearum) and the rice weevil, Sitophilus oryzae. Antifungal activity was quantified by measuring conidia germination inhibition and mycelial growth inhibition zone to determine the minimum inhibitory concentration (MIC). Mortality of insects was determined through either contact toxicity assay (impregnated filter paper) or fumigation toxicity assay (airtight exposure chamber). A four-parameter logistic regression of fungi inhibitory growth rate to the dose of tested substances, either by the agar diffusion assay or the micro-atmosphere test, showed that AITC had antifungal and sporicide activity. The concentration at MIC for A. westerdijkiae and F. graminearum was 24.2 and 19.8???l?l?1, respectively, whereas clove essential oil (EO) was 755 and 352???l?l?1 after 72?h incubation period. Bioassays with S. oryzae showed that clove EO contact insecticidal activity was similar to pure eugenol and carvacrol: LD90s were 366, 385 and 442???l?dm?2, respectively. The fumigation insecticidal activity of AITC was LC95?=?10.8???l?l?1. For EtF and clove EO, only the LC50 could be accurately determined after 24?h exposure time which was observed at 41 and 210???l?l?1, respectively (vs. 6.4???l?l?1 for AITC LC50). The combined antifungal activity on mycotoxigenic seed-borne fungi and insecticidal activity against the rice weevil demonstrated that AITC in vapour phase may be a promising active substance for the preservation grain stored in unsafe conditions with a risk of fungal growth. 相似文献
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Morten Eikenes Gry Alfredsen Bjørn Erik Christensen Holger Militz Halvor Solheim 《Journal of Wood Science》2005,51(4):387-394
Fungi cause serious problems in wood utilization, and environmentally benign wood protection is required as an alternative to traditional chemicals. Chitosan has shown promising antimicrobial properties against several microorganisms. In this study, we present the characterization of and antifungal properties of a commercial chitosan formulation developed for impregnation of wood. A broad range of chemical and mycological methods were used to evaluate the uptake, fixation, and antifungal properties of chitosan for wood preservation. The results show that the higher the uptake of chitosan the lower the relative recovery of chitosan in wood after leaching, and the higher the molecular weight of chitosan the higher the recovery. Chitosan with high molecular weight proved to be more efficient against decay fungi than chitosan with low molecular weight. The fungi tested on chitosan-amended nutrient agar medium were totally inhibited at 1% (w/v) concentration. In decay studies using small wood blocks, 4.8% (w/v) chitosan concentration gave the best protection against brown rot fungi. 相似文献
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Shams-Ghahfarokhi M Shokoohamiri MR Amirrajab N Moghadasi B Ghajari A Zeini F Sadeghi G Razzaghi-Abyaneh M 《Fitoterapia》2006,77(4):321-323
By using an agar dilution assay, the antifungal activity of aqueous extracts prepared from Allium cepa (onion; AOE) and Allium sativum (garlic; AGE) were evaluated against Malassezia furfur (25 strains), Candida albicans (18 strains), other Candida sp. (12 strains) as well as 35 strains of various dermatophyte species and compared with the activity of a known antifungal drug, ketoconazole (KTZ). All the AOE, AGE and KTZ were found to be able to inhibit growth of all fungi tested in a dose-dependent manner with maximum of 100% at defined concentrations. The results indicate that onion and garlic might be promising in treatment of fungal-associated diseases from important pathogenic genera Candida, Malassezia and the dermatophytes. 相似文献
20.
【目的】植物精油是一类安全环保且具有抑菌特性的天然产物,在木材霉变防治领域的应用潜力很大。开展植物精油对我国常见木材霉菌及变色菌的综合抑菌效力的研究,可为天然环保型木材霉变防治剂的开发提供重要依据。【方法】配制经植物精油修正的马铃薯葡萄糖琼脂培养基,通过评价霉变菌在培养基中的生长状况,对比分析19种植物精油对6种木材霉变菌的抑菌效力。【结果】在体积分数为0.05%的条件下,19种植物精油对黑曲霉Aspergillus niger、桔青霉Penicillam citrinum、绿色木霉Trichoderma viride、可可球二孢Botryodiplodia theobromae、串珠镰刀菌Fusarium moniliforme和链格孢霉Alternaria alternata的抑菌效力分别为0~100%、0~100%、0~100%、0~100%、11%~100%和20%~100%。聚类分析表明,肉桂、丁香花和百里香精油的综合抑菌效力最高,在体积分数0.05%的条件下对6种霉变菌的抑菌效力均达到100%,而尤加利、甜橙和松树精油的综合抑菌效力最低。相关分析表明,植物精油对6种霉变菌的抑菌效力之间均表现出显著相关性(P=0.01),其Pearson相关系数为0.777~0.959。【结论】不同植物精油的抑菌效力之间表现出较大差异,肉桂、丁香花和百里香精油是可以用于木材霉变防治的较优品种。 相似文献