一株木霉菌挥发性物质的抑菌活性测定及成分分析

目的：测定木霉菌XYT-12菌株的挥发性物质对植物病原真菌的抑制活性,并分析其挥发性物质的化学成分。方法：抑菌活性测定采用对扣法,化学成分分析采用气相色谱-质谱联用法（GC-MS）。结果：木霉菌XYT-12的挥发性物质对植物病原真菌有一定的抑制活性,以对番茄灰霉病菌的抑制作用最强,达到61.78%;木霉菌挥发性物质的主要成分为6-戊基-2H-吡喃-2-酮（6PP）,在菌丝和PDB培养液挥发物中的相对含量分别为90.346%和88.729%。     

中华羊茅内生真菌Epichlo? sp.挥发性物质的抑菌活性及成分分析

为测定中华羊茅内生真菌Epichloe sp.挥发性物质的抑菌活性和成分,依次采用挥发油提取器和乙酸乙酯萃取Epichloe sp.菌株的发酵产物,再采用琼脂扩散法、悬滴法和滤纸片扩散法测定其抑菌活性;基于顶空固相微萃取和气相质谱联用法分析挥发性物质成分。结果表明:挥发性物质、乙酸乙酯提取物、水相部分和发酵液可以抑制小麦根腐离蠕孢(Bipolaris sorokiniana)、新月弯孢(Curvularia lunata)和黑曲霉(Aspergillus niger)菌丝生长。高浓度的挥发性物质对四种真菌孢子萌发和芽管长度抑制效果显著高于低浓度(P<0.05)。结果表明,随着挥发性物质浓度的增加对金黄色葡萄球菌(Staphylococcus aureus)和大肠杆菌(Escherichia coli)的抑菌作用增强,同一挥发性物质浓度对金黄色葡萄球菌的抑制作用强于大肠杆菌。此外,从挥发性物质中鉴定出32种具有较高质谱匹配度的化合物,其中主要成分包括异山梨醇(16.26%)、甲基叔丁基醚(8.18%)、二氢甘露醇(3.75%)、羟基丙酮(2.99%)、乙酸(1.22%)、己醇(1.20%)、3-糠醛(0.92%)、5-羟甲基二氢呋喃-2-酮(0.86%)、5-羟基戊酸-2,4-二叔丁基苯酯(0.86%)和棕榈酸甲酯(0.85%)。总之,中华羊茅内生真菌Epichlosp.挥发性物质具有拮抗细菌和真菌的作用。     

冷饭团不同部位挥发性成分及抗氧化活性分析

为较全面地认识冷饭团(Kadsura coccinea)植株挥发性成分及其抗氧化活性,该研究以其根、茎、叶为材料,采用水蒸气蒸馏提取法(方法 a)和顶空-固相微萃取法(SPME)(方法 b)结合气相色谱-质谱联用技术(GC-MS)与计算机检索技术,对冷饭团植株各部位挥发性成分进行了提取分析,并采用DPPH法对其抗氧化活性进行测试。结果表明:(1)两种提取方法检测出的挥发性成分种类及含量存在一定差异,用方法a和方法 b分别在根、茎、叶中共鉴定出挥发性化合物98和117种;其中根中分别有59与68种(占总挥发性物质的83.5%,93.8%)、茎中54和56种(占总挥发性物质的88.9%,94.9%)、叶中36和42种(占总挥发性物质的89.6%,97.7%)。(2)根、茎、叶中两种方法检出共同化合物种类及含量基本相同,主要有石竹烯、蒎烯、榄香烯、毕澄茄油烯、古巴烯、毕澄茄烯、d-苦橙花醇等,这些成分也是各部分挥发物的主要成分(含量超过70%)。(3)根、茎、叶中挥发性物质质量浓度达到20 mg·m L~(-1)时,清除DPPH自由基效率均超过97%,表现出很好的抗氧化活性。     

棘托竹荪菌托抑菌物质提取、分离及活性组分北大核心CSCD

以棘托竹荪(Dictyophora echinovolvata)菌托为研究对象,提纯菌托提取物有效抑菌天然产物,分析其抑菌活性组成。选择最佳提取溶剂及指示菌,采用色谱层析法分离纯化,GC-MS检测分析活性组分。结果表明:乙酸乙酯提取物对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、蜡状芽孢杆菌、标准摩根氏菌、肠炎沙门氏菌均有较好的抑制效果;以金色葡萄球菌为指示菌,乙酸乙酯提取物的抑菌作用对温度、紫外线均有较好的稳定性;对提取物进行分离,获得2个有抑菌活性组分DEVⅠ、DEVⅡ,采用GC-MS分析DEVⅠ、DEVⅡ中的化学组分,DEVⅠ中相对含量1%以上的成分有20个;DEVⅡ中相对含量在1%以上成分6个,其中具有抑菌活性的成分为2-呋喃甲酸和肉桂酸,相对含量分别为25.6%和54.2%,推测可能为棘托竹荪菌托抑菌物质的主要组成成分。     

肉桂不同植物部位精油成分分析及抑菌活性研究

本研究选用肉桂(Cinnamomum cassia)的桂皮、桂叶、桂枝、果实、花萼5种植物部位为研究对象,通过气质联用对各部位精油的主要成分组成进行了分析比较。在此基础上,从抑菌圈、最低抑菌浓度(MIC)、最低杀菌浓度(MBC)等方面比较各部位精油对金黄色葡萄球菌(Staphylococcus aureus)、大肠杆菌(Escherichia coli)抑制活性。结果表明,各部位精油中的主要成分均为反式肉桂醛、邻甲氧基肉桂醛等,但各成分的含量存在明显差异,以花萼中的反式肉桂醛含量最高(87.68%)。各部位精油对两种供试微生物均具有显著抑菌效果,以桂枝中所含精油的抑菌效果最佳,对E.coli和S.aureus的MIC分别为0.05%和0.025%,MBC同样也分别为0.05%和0.025%。     

地木耳中脂溶性物质抑菌活性研究

采用索氏提取法从地木耳中提取脂溶性物质,经硅胶柱层析将脂溶性物质分离成石油醚洗脱组分(非极性脂)、苯洗脱组分(弱极性脂)和乙醇洗脱组分(强极性脂),并对脂溶性物质和3种洗脱组分进行抑菌活性研究,以促进地木耳的综合应用。结果表明,地木耳中脂溶性物质含量为2.62%。其中,非极性石油醚洗脱组分含量最高,占总脂的54%,但无抑菌活性;强极性的乙醇洗脱组分含量其次,占总脂的32%,其抑菌活性最强;弱极性苯洗脱组分含量最低,占总脂的14%,有弱抑菌活性。地木耳脂溶性物质对6种菌有较好的抑制作用,其抑制能力大小为:大肠杆菌金黄色葡萄球菌枯草芽孢杆菌黑曲霉酿酒酵母假单胞杆菌。     

地胆草与白花地胆草脂溶性成分的GC-MS分析及抑菌活性研究

采用溶剂萃取法提取地胆草(Elephantopusscaber Linn.)和白花地胆草(Elephantopustomentosus Linn.)的脂溶性成分,经GC-MS分析,从地胆草中鉴定出44种化学成分,占总脂溶性成分的93.72%;从白花地胆草中鉴定出25种化学成分,占总脂溶性成分的82.08%。地胆草和白花地胆草在萜类成分含量具有显著性差异。通过滤纸片琼脂扩散法测试其抗菌活性,结果表明地胆草与白花地胆草的脂溶性成分对耐甲氧西林金黄色葡萄球菌(MRSA)和金黄色葡萄球菌均有抑制活性,且白花地胆草的抑菌活性强于地胆草。     

银杏内生细菌的分离鉴定及抑菌活性初探

【目的】从银杏(Ginkgo biloba)茎叶中分离鉴定内生细菌, 测定其体外抑菌活性及对辣椒果疫病的防治效果。【方法】采用平板对峙法筛选出对辣椒疫霉菌(Phytophthora capsici)有拮抗作用的内生细菌, 并用平板对扣法测定其中一株防治效果较好的内生细菌产生的挥发性物质对辣椒疫霉菌生长的影响。通过生防菌液和病原菌孢子悬浮液喷雾接种辣椒果测定该菌株对辣椒果疫病的防治效果。基于形态特征、生理生化特性、16S rDNA和gyrA基因序列同源性分析鉴定该生防菌株。【结果】从银杏的茎和叶中分离获得9株内生细菌。平板对峙生长试验结果表明, 菌株W5对供试的辣椒疫霉菌、稻瘟病菌(Pyricularia grisea)、水稻纹枯菌(Rhizoctonia solani)、黄瓜枯萎病菌(Fusarium oxysporum)、荔枝霜疫霉菌(Peronophythora litchi)、荔枝酸腐菌(Geotrichum candidum)均有抑制作用, 其中对辣椒疫霉菌、稻瘟病菌和荔枝霜疫霉菌的抑菌效果显著, 抑菌率分别为88.9%、86.3%和90.2%。其产生的挥发性物质能明显抑制辣椒疫霉菌菌丝的生长。对辣椒采后果疫病的防治效果表明, 先喷雾接种W5菌悬液24 h后再接种辣椒疫霉病菌孢子悬浮液的防治效果最好, 可将辣椒果的保鲜期延长2?3 d。该菌株被鉴定为解淀粉芽胞杆菌(Bacillus amyloliquefaciens)。【结论】获得了一株对植物病原菌物有良好防治效果的银杏内生解淀粉芽胞杆菌W5, 对辣椒采后果疫病及其他病原真菌的防治具有潜在应用价值。     

枯草芽孢杆菌JA脂肽类及挥发性物质抑菌效应的研究

枯草芽孢杆菌JA产生的脂肽类抗生素对植物病原真菌有广谱抗性。将发酵液经过酸沉淀、甲醇抽提以及反相高效液相色谱等步骤, 分离得到脂肽类抗生素的纯品。经IC50实验和抗菌谱测定, 考察了脂肽类抗生素对多种植物病原菌的作用, 确定了脂肽类抗生素的抗菌谱。深入研究表明, 枯草芽孢杆菌JA还产生未知成分的挥发性抑菌物质, 能够抑制灰霉病菌孢子的萌发和菌丝的生长。脂肽类抗生素和挥发性抑菌物质的协同作用, 有助于提高枯草芽孢杆菌的生物防治效果。     

苦豆籽中抑菌活性物质的跟踪筛选研究

目的:对苦豆籽中抑菌活性物质进行跟踪筛选。方法:采用溶剂萃取法获得苦豆籽不同极性溶剂萃取的浸膏,对其浸膏及实验室自制单体类化合物通过纸片扩散法(K-B)法进行抑菌试验研究。结果:苦豆籽粗提物对实验所用菌种都有不同程度的抑制作用,尤其是氯仿浸膏中可能含大量生物碱,因此表现出强的抑菌效果;苦豆籽单体类化合物对实验所用菌种都具有较强的抑制作用,苦参碱的抑菌效果最好。结论:苦豆籽中主要抑菌成分为生物碱类化合物,其中苦参碱的抑菌效果优于氧化苦参碱。     

Antifungal Activity of Volatile Compounds Produced by an Edible Mushroom Hypsizygus marmoreus against Phytopathogenic Fungi

Volatile compounds with antifungal activity produced by edible mushrooms have potential as biological control agents to combat fungal diseases and reduce fungicide use in agriculture. Here we investigated the antifungal activity of volatile compounds produced by the edible mushroom Hypsizygus marmoreus (TUFC 11906) against eight phytopathogenic fungi. The results showed that volatile compounds from the mycelia and culture filtrates (CFs) of H. marmoreus had antifungal activity against some phytopathogenic fungi. Among them, the mycelial growth and conidial germination of Alternaria brassicicola were significantly inhibited by 60 and 100%, respectively. Moreover, the volatile compounds from CFs inhibited the lesion formation of A. brassicicola on detached cabbage leaves by 94%. The volatile compounds had higher antifungal activity against A. brassicicola than other fungi. With the removal of the volatile compounds from conidia of A. brassicicola, the conidia began to germinate, which indicates fungistatic activity of the compounds. The volatile compounds were isolated from the CFs of H. marmoreus, and the major volatile compound with antifungal activity was estimated to be 2‐methylpropanoic acid 2,2‐dimethyl‐1‐(2‐hydroxy‐1‐methylethyl)propyl ester. As the volatile compound produced by H. marmoreus is a product of an edible mushroom and has fungistatic activity against some phytopathogenic fungi, especially A. brassicicola, it may be possible to use the compounds as a novel safe agent for protecting crops in the field and during storage.     

火棘花挥发油化学成分的GC-MS分析及抗氧化活性研究

采用水蒸气蒸馏法提取火棘花挥发油,利用气相色谱—质谱联用技术(GC-MS)分析其化学成分。使用维生素C和BHT为阳性对照,以DPPH自由基、亚硝酸钠清除作用为指标评价挥发油的抗氧化活性。从挥发油中鉴定了77个化合物,占挥发油总量的83.77%,含有多种生物活性成分,以萜类及其含氧衍生物(50.31%)、烷烃(18.52%)、醛(5.54%)为主;挥发油对DPPH自由基、亚硝酸钠有明显的清除作用,清除率为50%时,其体积分别为43.51、79.48μL,样品量与清除率间呈量效关系;挥发油对DPPH自由基的清除效果略低于1 mg·mL-1维生素C,对亚硝酸钠的清除效果优于1 mg·mL-1的BHT。     

雪松松针挥发油化学成分及抗氧化活性研究

采用水蒸气蒸馏法提取雪松松针挥发油,利用气相色谱-质谱联用技术分析其化学成分。使用维生素C为阳性对照,以DPPH自由基、ABTS自由基和羟基自由基清除作用为指标评价挥发油的抗氧化活性。从雪松松针挥发油中鉴定了37种化学成分,占挥发油总量的95.10%,以烃类和醇类为主;挥发油对DPPH自由基、ABTS自由基和羟基自由基有明显的清除作用,其IC₅₀分别为0.30、0.22及0.96 μg·mL^-1,且呈现一定的量效关系。可见,雪松松针挥发油中含有多种有应用价值的化学成分,具有显著的抗氧化活性。     

糖蜜草挥发性成分HS-SPME-GC-MS分析

本文首次采用顶空固相微萃取技术(HS-SPME)提取该植物挥发性成分,然后通过气质联用技术(GC-MS)结合保留指数以及标样对照对化学成分进行了定性,并通过峰面积归一化法计算出各组分的相对百分含量。试验确定了PDMS/DVB固相微萃取对糖蜜草挥发物的萃取效果最好,并从中鉴定出33种化合物占总挥发性成分的90.94%,主要为烷烃和萜烯类化合物。该研究为开发糖蜜草作为水稻螟虫的驱避植物进行害虫安全有效防治提供理论依据,并为驱避性挥发物的田间应用奠定基础。     

山鸡椒植物源抑菌成分的筛选研究

以山鸡椒为植物材料,以活性追踪的方法测定了不同组分对几种植物病原菌的抑制活性,并从中分离纯化出一种有效抗菌物质L1。实验结果表明:粗提物不同萃取相中,乙酸乙酯相的抑制作用最好,其对杨树溃疡病菌和苹果霉心病菌抑制率达到75%以上;乙酸乙酯相各个组分对几种植物病原真菌均有一定的抑制活性,其中组分6和组分7抑菌效果强,组分6对苹果霉心病菌抑制率达到100%,组分7对番茄灰霉病菌抑制率达到100%;而对抑菌活性物质L1的抑菌活性研究中,随着L1浓度逐渐升高,对几种病原菌的抑制作用也依次增强,尤其是对苹果霉心病菌的抑制效果更加明显,在供试浓度为0.1 mg/mL时,抑制率达到100%;活性成分L1最终通过波谱学方法和文献对比确定为5,8-二羟基-67,-二甲氧基黄酮。     

An Antifungal Tetrapeptide from the Culture of Penicillium canescens

A new tetrapeptide D ‐Phe‐L ‐Val‐D ‐Val‐L ‐Tyr ( 1 ), along with three known diketopiperazines and pseurotin A, were isolated from the culture of Penicillium canescens, collected from pollen from beehives, in a screening for new antimicrobial products from unexplored sources. The structure of the tetrapeptide, which exhibits antifungal activity comparable with that of the commercial product benomyl against the soybean phytopathogen Fusarium virguliforme, was determined by spectroscopic (2D‐NMR, and MS and MS/MS) and chemical methods, and the sequence was confirmed by comparison with authentic synthetic isomeric peptides.     

水果中抗病原真菌物质成分的提取分离方法及应用前景

诱发因子如草酸,拮抗菌产生的抗素等,以及采后热处理,紫外线处理可以诱导水果产生抗病性,此外有的水果具有先天性抗病成分,对这些活性成分进行分析,并用之于水果采后病害的生物防治,为水果的防腐保鲜提供了新的方法,追踪这些抗病物质的产生和分布,需要采用一些专门的分析方法,目前采用的方法是将果实组织破碎,离心,通过萃取,层析或电泳技术进行纯化,然后用核磁共振,X－射线衍射及各种波谱分析技术进行结构鉴定,抗真菌物质的活性可以用薄层层层析生物学方法,孢子萌发或纸碟法进行鉴定,而抗真菌活性物质的定位则用组织化学法,电子显微术,放射自显著技术和免疫印迹技术也广泛用物于组织化学分析。     

Antifungal Activity and Action Mechanism Study of Coumarins from Cnidium monnieri Fruit and Structurally Related Compounds

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC₅₀ value of 21 μg mL⁻¹. Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the β-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.     

Antifungal effect of Penicillium metabolites against some fungi

Microorganisms are increasingly exploited as a source of new biological control agents. Genus Penicillium is a source of novel bioactive molecules which can be used as antifungal agents. The objective of this study was to evaluate the antifungal potential of Penicillium strains. Culture filtrates of two Penicillium species were tested for their antifungal potential by well diffusion assays. Filtrate of Penicillium isolates showed high antifungal effects on mycelial growth of Fusarium oxysporum, Fusarium solani, Macrophomina phaseolina, Aspergillus japonicus var aculeatus and Cladosporium cladosporioides. But Penicillium italicum inhibit the fungal growth from 45 to 68% as compared to Penicillium simplissimum (25–68%). However in case of A. japonicus var aculeatus, Penicillium spp. extracts were equally effective and reduce the colony growth up to 68%. However, P. simplissimum extract was least effective in case of M. phaseolina, where it decreased the colony growth only 25%.