Synthesis and antimicrobial activity of new 1,2,4-triazole and 1,3,4-thiadiazole derivatives

In this study, new 3-[(1(2H)-phthalazinone-2-yl(methyl/ethyl]-4-aryl-1,2,4-triazole-5-thione and 2-[[1(2H)-phthalazinone-2-yl]methyl/ethyl]-5-arylamino-1,3,4-thiadiazole derivatives were synthesized. Antimicrobial properties of the title compounds were investigated against two Gram (+) bacteria (S. aureus, B. subtilis), two Gram ( - ) bacteria (P. aeruginosa, E. coli) and two yeast-like fungi (C. albicans and C. parapsilosis) using the broth microdilution method. Generally the compounds were found to be active against B. subtilis and the fungi. Derivatives carrying a 1,3,4-thiadiazole ring generally showed higher antimicrobial activity against B. subtilis and the fungi when compared to other synthesized compounds.     

Synthesis and antibacterial activity of egonol derivatives

Synthesis of egonol derivatives, 5-(3'-chloropropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 1, 5-(3'-bromopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 2, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propanal 3, 5-(3'-iodopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 4, 5-[3-(3'-bromopropyloxy) propyl]-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 5, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylmethanoate 6, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propyloleate 7, 5-[3'-hydroxypropyl]-6-bromo-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 8, 4-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]butanenitrile 9, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylbenzoate 10, 5-[3'-hydroxypropyl]-7-methoxy-3-nitro-2-(3',4'-methylenedioxyphenyl)benzofuran 11 and their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli are reported. The starting material egonol 5-[3'-(hydroxy)propyl]-7-methoxy-2-(3', 4'methylenedioxyphenyl)benzofuran was isolated from seeds of Styrax officinalis L. The structural elucidication of these compounds (1-11) was established using 1D ((1)H, (13)C), 2D NMR (HMBC, HMQC, COSY) and LCMS spectroscopic data. While egonol and some synthesised new compounds show similar antibacterial activity and MIC values against S. aureus, B. subtilis, C. albicans and E. coli, other new derivatives show different activity against S. aureus, B. subtilis, C. albicans and E. coli.     

柑橘内生真菌的分离鉴定及其发酵产物对柑橘溃疡病菌的抑制活性

本研究从柑橘抗病品种的健康植株不同组织中分离纯化和鉴定内生真菌,并测定其发酵产物对柑橘溃疡病菌的抑制活性,以明确柑橘抗病品种中内生真菌的组成及其产抗柑橘溃疡病菌活性代谢产物的潜力,为柑橘溃疡病抗菌剂的开发奠定基础。该研究通过组织培养法分离内生真菌,采用形态学和分子生物学方法对其进行鉴定; 基于前期的拮抗预试验结果,选取代表性菌株进行发酵培养,通过乙酸乙酯浸提、真空抽滤、旋转蒸发浓缩制备粗提物; 采用带毒平板涂布法测定不同菌株发酵产物乙酸乙酯提取物对柑橘溃疡病菌的抑制活性。结果表明:(1)共分离得到72株内生真菌,归为2门(Ascomycota、Basidiomycota)、14个属,其中优势属为刺盘孢属(Colletotrichum)、球座菌属(Guignardia)、链格孢属(Alternaria)和镰刀菌属(Fusarium)。(2)不同柑橘品种中内生真菌多样性指数为温州蜜柑(桂林)>沙糖桔(桂林)>沙糖桔(梧州)。(3)不同组织中内生真菌多样性变化因地理位置差异而有所不同,采自桂林的温州蜜柑和沙糖桔均为叶片中的内生真菌的多样性高于枝条,而采自梧州的沙糖桔为叶片中的多样性低于枝条,并且采自梧州的柑橘样品与采自桂林的柑橘样品中的内生真菌相似性低。(4)测定了30株内生真菌乙酸乙酯提取物对柑橘溃疡病菌的抑制活性,其中29株菌株表现出不同程度抑制活性。不同柑橘品种中的优势属的MIC介于0.312 5～10 mg·mL^-1之间,特有属的MIC介于0.156～5 mg·mL^-1,共有属镰刀菌属的MIC介于0.312 5～2.5 mg·mL^-1之间。研究结果表明柑橘抗病品种中内生真菌具有丰富多样性,并且其发酵提取物普遍对柑橘溃疡病菌具有抑制作用。特有属抑菌活性总体优于优势属,共有属镰刀菌属在不同柑橘抗病品种中均具有显著抑菌效果。     

Manganese superoxide dismutase in pathogenic fungi: an issue with pathophysiological and phylogenetic involvements

Manganese-containing superoxide dismutases (MnSODs) are ubiquitous metalloenzymes involved in cell defence against endogenous and exogenous reactive oxygen species. In fungi, using this essential enzyme for phylogenetic analysis of Pneumocystis and Ganoderma genera, and of species selected among Ascomycota, Basidiomycota and Zygomycota, provided interesting results in taxonomy and evolution. The role of mitochondrial and cytosolic MnSODs was explored in some pathogenic Basidiomycota yeasts (Cryptococcus neoformans var. grubii, Cryptococcus neoformans var. gattii, Malassezia sympodialis), Ascomycota filamentous fungi (Aspergillus fumigatus), and Ascomycota yeasts (Candida albicans). MnSOD-based phylogenetic and pathogenic data are confronted in order to evaluate the roles of fungal MnSODs in pathophysiological mechanisms.     

Antimicrobial activity in cultures of endophytic fungi isolated from Garcinia species

The aim of the present study was to screen for antimicrobial activity in endophytic fungi isolated from surface sterilized leaves and branches of five Garcinia plants, G. atroviridis, G. dulcis, G. mangostana, G. nigrolineata and G. scortechinii, found in southern Thailand. Fermentation broths from 377 isolated fungi were tested for antimicrobial activity by the agar diffusion method. Minimum inhibitory concentrations (MICs) were obtained for crude ethyl acetate extracts. Seventy isolates (18.6%) displayed antimicrobial activity against at least one pathogenic microorganism, such as Staphylococcus aureus, a clinical isolate of methicillin-resistant S. aureus, Candida albicans and Cryptococcus neoformans. The results revealed that 6-10%, 1-2% and 18% of the crude ethyl acetate extracts inhibited both strains of S. aureus (MIC 32-512 microg mL(-1)), Ca. albicans and Cr. neoformans (MIC 64-200 microg mL(-1)), and Microsporum gypseum (MIC 2-64 microg mL(-1)), respectively. Isolates D15 and M76 displayed the strongest antibacterial activity against both strains of S. aureus. Isolates M76 and N24 displayed strong antifungal activity against M. gypseum. Fungal molecular identification based on internal transcribed spacer rRNA gene sequence analysis demonstrated that isolates D15 (DQ480353), M76 (DQ480360) and N24 (DQ480361) represented Phomopsis sp., Botryosphaeria sp. and an unidentified fungal endophyte, respectively. These results indicate that some endophytic fungi from Garcinia plants are a potential source of antimicrobial agents.     

Three oxygenated cyclohexenone derivatives produced by an endophytic fungus

Three cyclohexenone derivatives, (4S,5S,6S)-5,6-epoxy-4-hydroxy-3-methoxy-5-methyl-cyclohex-2-en-1-one (1), (4R,5R)-4,5-dihydroxy-3-methoxy-5-methyl-cyclohex-2-en-1-one (2), and (4R,5S,6R)-4,5,6-trihydroxy-3-methoxy-5-methyl-cyclohex-2-en-1-one (3), were isolated from unpolished rice fermented with an xylariaceous endophytic fungus (strain YUA-026). The structures of three compounds were established on the basis of spectroscopic analyses and chemical conversion. The minimum inhibitory concentrations of 1 and 3 were 100 microg/ml and 400 microg/ml against Staphylococcus aureus, 100 microg/ml and 200 microg/ml against Pseudomonas aeruginosa, and 200 microg/ml and >400 microg/ml against Candida albicans, respectively. In addition, 1 and 3 exhibited phytotoxic activity against lettuce.     

Diversity and Antimicrobial Activity of Culturable Endophytic Fungi Isolated from Moso Bamboo Seeds

Bamboos, regarded as therapeutic agents in ethnomedicine, have been used to inhibit inflammation and enhance natural immunity for a long time in Asia, and there are many bamboo associated fungi with medical and edible value. In the present study, a total of 350 fungal strains were isolated from the uncommon moso bamboo (Phyllostachys edulis) seeds for the first time. The molecular diversity of these endophytic fungi was investigated and bioactive compound producers were screened for the first time. All the fungal endophytes were categorized into 69 morphotypes according to culturable characteristics and their internal transcriber spacer (ITS) regions were analyzed by BLAST search with the NCBI database. The fungal isolates showed high diversity and were divided in Ascomycota (98.0%) and Basidiomycota (2.0%), including at least 19 genera in nine orders. Four particular genera were considered to be newly recorded bambusicolous fungi, including Leptosphaerulina, Simplicillium, Sebacina and an unknown genus in Basidiomycetes. Furthermore, inhibitory effects against clinical pathogens and phytopathogens were screened preliminarily and strains B09 (Cladosporium sp.), B34 (Curvularia sp.), B35 (undefined genus 1), B38 (Penicillium sp.) and zzz816 (Shiraia sp.) displayed broad-spectrum activity against clinical bacteria and yeasts by the agar diffusion method. The crude extracts of isolates B09, B34, B35, B38 and zzz816 under submerged fermentation, also demonstrated various levels of bioactivities against bambusicolous pathogenic fungi. This study is the first report on the antimicrobial activity of endophytic fungi associated with moso bamboo seeds, and the results show that they could be exploited as a potential source of bioactive compounds and plant defense activators. In addition, it is the first time that strains of Shiraia sp. have been isolated and cultured from moso bamboo seeds, and one of them (zzz816) could produce hypocrellin A at high yield, which is significantly different from the other strains published.     

Metabolites from the endophytic fungus Xylaria sp. PSU-D14

Glucoside derivatives, xylarosides A (1) and B (2), were isolated from the broth extract of the endophytic fungus Xylaria sp. PSU-D14 along with two known compounds, sordaricin (3) and 2,3-dihydro-5-hydroxy-2-methyl-4H-1-benzopyran-4-one (4). The structures were assigned by spectroscopic methods. Sordaricin (3), one of the known metabolites, exhibited moderate antifungal activity against Candida albicans ATCC90028 with a MIC value of 32 microg/ml.     

Chemistry and weak antimicrobial activities of phomopsins produced by mangrove endophytic fungus Phomopsis sp. ZSU-H76

Three metabolites named phomopsin A (1), B (2) and C (3), together with two known compounds cytosporone B (4) and C (5), were isolated from the mangrove endophytic fungus, Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly by 1D and 2D NMR spectroscopic techniques. The medium-sized cyclic phenol ether based on 1 or 2 is rare in natural products. In bioassays, compounds 1, 2, and 3 had no significant antibiotic activities, but compounds 4 and 5 inhibited two fungi Candida albicans and Fusarium oxysporum with an MIC ranging from 32 to 64 microg/ml.     

Two new resorcinol derivatives with strong cytotoxicity from the roots of Ardisia brevicaulis Diels

Two new resorcinol derivatives, 4-hydroxy-2-methoxy-6-[(8Z)-pentadec-8-en-1-yl]phenyl acetate (1) and 4-hydroxy-2-methoxy-6-pentadecylphenyl acetate (2), together with known compounds ardisiphenol D (3), 5-tridecylresorcinol (4), 5-pentadecylresorcinol (5), 5-[(8Z)-pentadec-8-en-1-yl]resorcinol (6), belamcandaquinones C and D (7 and 8, resp.), ardisicrenoside A, ardisiacrispin B, (22E)-24-ethyl-5α-cholesta-7,22-dien-3-one, and (22E)-24-ethyl-5α-cholesta-7,22-dien-3β-ol were isolated from the MeOH extract of the roots of Ardisia brevicaulis Diels. Their structures were determined by spectroscopic analysis including ESI- and EI-MS, and NMR data. Cytotoxicities of 1-4 against cell lines A549, MCF-7, and PANC-1 were tested in vitro by the MTT (=3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) method. Compounds 1-4 showed cytotoxic activity against all cell lines stronger than that of cisplatin against A549.     

云南、浙江、内蒙古禾本科植物内生真菌多样性研究

从云南、浙江和内蒙古的30属禾本科植物分离到1821株内生真菌,根据ITSrDNA系统发育分析和ITS预测真菌的阈值,将这些菌株鉴定为3门10纲34目216属,其中子囊菌门5纲26目192属,担子菌门3纲6目21属,毛霉门2纲2目3属.粪壳菌纲和座囊菌纲为主要优势纲,相对频率分别为54.8％和30.9％;座囊菌纲的格孢...     

云南三个地区马铃薯内生真菌多样性研究

为研究云南马铃薯(Solanum tuberosum)内生真菌的多样性,该文以采自云南省德宏芒市、大理喜洲和临沧双江3个地区的马铃薯植株为研究对象,采用组织块分离法、尖端菌丝挑取法对马铃薯根、茎及块茎中的内生真菌进行分离纯化,并采用形态学鉴定方法和ITS序列分析法对分离得到的内生真菌进行鉴定,对内生真菌的定殖率、分离率及多样性指数进行计算和分析。结果表明:(1)共分离得到内生真菌98株,其中从德宏芒市的样品中获得40株,从大理喜洲的样品中获得27株,从临沧双江的样品中获得31株。(2)经鉴定,分离得到的马铃薯内生真菌共涵盖10目10科13属,大多为子囊菌门和担子菌门,优势菌为镰刀菌属(Fusarium)和青霉属(Penicillium),褶皱裸孢壳(Emericella rugulosa)、接骨木镰刀菌(Fusarium sambucinum)、毛韧革菌(Stereum hirsutum)、Psathyrella sulcatotuberculosa和Epicoccum catenisporum 5种真菌均为首次从马铃薯植株中分离得到。(3)马铃薯块茎内生真菌的定殖率最高,根部内生真菌定殖率最低; 内生真菌的分离率以马铃薯根部为最高,而茎部最低; 不同组织中内生真菌的多样性指数趋势均为根>块茎>茎。从综合来看,云南马铃薯植株中的内生真菌具有较高的多样性,不同地区的马铃薯样品中内生真菌优势菌不同,马铃薯根部具有最丰富的内生真菌种群和最高的分离率,是最适合进行内生真菌分离的材料。该研究结果为后期探究马铃薯内生真菌对病原菌的拮抗作用奠定了基础,也为马铃薯内生真菌多样性研究提供了参考数据。     

Biologically Active Metabolites Produced by the Basidiomycete Quambalaria cyanescens

Four strains of the fungus Quambalaria cyanescens (Basidiomycota: Microstromatales), were used for the determination of secondary metabolites production and their antimicrobial and biological activities. A new naphthoquinone named quambalarine A, (S)-(+)-3-(5-ethyl-tetrahydrofuran-2-yliden)-5,7,8-trihydroxy-2-oxo-1,4-naphthoquinone (1), together with two known naphthoquinones, 3-hexanoyl-2,5,7,8-tetrahydroxy-1,4-naphthoquinone (named here as quambalarine B, 2) and mompain, 2,5,7,8-tetrahydroxy-1,4-naphthoquinone (3) were isolated. Their structures were determined by single-crystal X-ray diffraction crystallography, NMR and MS spectrometry. Quambalarine A (1) had a broad antifungal and antibacterial activity and is able inhibit growth of human pathogenic fungus Aspergillus fumigatus and fungi co-occurring with Q. cyanescens in bark beetle galleries including insect pathogenic species Beauveria bassiana. Quambalarine B (2) was active against several fungi and mompain mainly against bacteria. The biological activity against human-derived cell lines was selective towards mitochondria (2 and 3); after long-term incubation with 2, mitochondria were undetectable using a mitochondrial probe. A similar effect on mitochondria was observed also for environmental competitors of Q. cyanescens from the genus Geosmithia.     

Synthesis and SAR studies of biaryloxy-substituted triazoles as antifungal agents

A series of 1-(substituted biaryloxy)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl) propan-2-ol were synthesized and their antifungal activities were evaluated against eight human pathogenic fungi in vitro. Seventeen compounds showed activity 4- to 64-fold higher than voriconazole against Candida albicans. SAR clearly suggested that introduction of a biaryloxy side chain greatly enhanced the antifungal activity of triazole analogs against Candida species.     

Diversity and antimicrobial activities of the fungal endophyte community associated with the traditional Brazilian medicinal plant Solanum cernuum Vell. (Solanaceae)

The diversity and antimicrobial activity of endophytic fungi associated with the Brazilian medicinal plant Solanum cernuum Vell. were studied during summer and winter seasons. A total of 246 fungal isolates were obtained, including 225 filamentous fungi and 21 yeasts. They were identified by morphological, physiological, and molecular methods. Fifty-five different taxa represented by the phyla Ascomycota (33 taxa), Basidiomycota (21 taxa), and Zygomycota (one taxon) were identified. The most abundant taxa were closely related to Arthrobotrys foliicola , Colletotrichum gloeosporioides , Coprinellus radians , Glomerella acutata , Diatrypella frostii , Phoma glomerata , Mucor sp., Phlebia subserialis , Phoma moricola , Phanerochaete sordida , and Colletotrichum sp. A total of 265 fungal extracts were screened and 64 (26.01%) displayed antimicrobial activities. Among these extracts, 18 (28.12%) presented antibacterial and antifungal activities, 42 (65.62%) displayed selective antibacterial activity, and four (6.25%) exhibited only antifungal activity. The best values of minimum inhibitory concentration were obtained from extracts of Cryptococcus rajasthanensis , Glomerella acutata, Leptosphaeria sp., and Phoma glomerata ranging from 7.8 to 15.62?μg/mL. This study is the first survey of the endophytic fungi community associated with S. cernuum, and our results show that they can represent a promising source of bioactive compounds.     

Synthesis of new isoxazoles and dihydroisoxazoles and in vitro evaluation of their antifungal activity

New 2-(2,4-dihalogenophenyl)-1-(1H-imidazol-1-yl)-3-(isoxazol-5-yl)propan-2-ols and 2-(2,4-dihalogenophenyl)-1-(1H-imidazol-1-yl)-3-(4,5-dihydroisoxazol-5-yl)propan-2-ols were synthesized by 1,3-dipolar cycloaddition between homopropargylic or homoallylic alcohols and in-situ generated nitrile oxide. Their antifungal activity was evaluated against Candida albicans, C. glabrata, Aspergillus fumigatus and an azole-resistant petite mutant of C. glabrata. Preliminary SAR results are discussed.     

北柴胡种子内生菌群落结构与多样性

为研究北柴胡种子内生菌的群落结构与多样性.采用Illumina Miseq高通量测序技术,分别对山西(BC_1)、黑龙江(BC_2)、河北(BC_3)和内蒙古(BC_4)的四个产地(4份)北柴胡种子的16S RNA V3-V4区和ITS1区扩增片段进行测序,并对内生细菌和内生真菌群落结构和多样性进行分析.结果表明,BC...     

A new antifungal briarane diterpenoid from the gorgonian Junceella juncea Pallas

A new 8-hydroxy briarane diterpenoid (compound 1) with antifungal activity was isolated along with known compounds (2-5) from the gorgonian coral Junceellajuncea. On the basis of spectroscopic data (1D and 2D NMR, MS), the structure of the compound 1 was established as (1S,2S,8S,9S,10S,11R,12R,14S,17R)-11,20-epoxy-14-(3-methylbutanoyl)-2,9,12-triacetoxy-8-hydroxybriar-5(16)-en-18,7-olide. Compound 1 exhibited significant activity against fungi (Aspergillus niger, Candida albicans and Penicillium notatum) but the other compounds (2-5) did not exhibit the activity against fungi.     

Diversity,Molecular Phylogeny,and Bioactive Potential of Fungal Endophytes Associated with the Himalayan Blue Pine (Pinus wallichiana)

In this study, we investigated the diversity of fungal endophytes associated with Pinus wallichiana from the Western Himalayas, with emphasis on comparison of endophytic communities harbored by the stem and needle tissues of the host and their antimicrobial potential. A total number of 130 isolates, comprising of 38 different genera, were recovered from 210 fragments of the plant. Among the isolated fungi, only a single isolate, Tritirachium oryzae, belonged to the Phylum Basidiomycota whereas the rest belonged to Ascomycota. Dothideomycetes was the dominant class with the highest isolation frequency of 49.2 %. The most frequent colonizers of the host were Alternaria spp., Pestalotiopsis spp., Preussia spp., and Sclerostagonospora spp. The diversity and species richness were higher in needle tissues than in the stems. Antimicrobial activities were displayed by extracts from a total number of 22 endophytes against one or more pathogens. Endophytes designated as P1N13 (Coniothyrium carteri), P2N8 (Thielavia subthermophila), P4S6b (Truncatella betulae), P7N10 (Cochliobolus australiensis), and P8S4 (Tritirachium oryzae) were highly active against Candida albicans. Broad spectrum antimicrobial activities were obtained with the extracts of P8-S4 (Tritirachium oryzae) and P5-N26 (Coniochaeta gigantospora) that were potentially active against the Gram-positive and Gram-negative bacteria as well as the fungal pathogen, Candida albicans. The most prominent antagonistic activity against fungal pathogens was shown by P8-S4 (Tritirachium oryzae), P5-N31a (Truncatella spadicea), and P5-N20 (Fusarium larvarum). Our findings indicate that Pinus wallichiana harbors a rich endophytic fungal community with potential antimicrobial activities. Further studies are needed to understand the ecology and evolutionary context of the associations between the Himalayan pine and its endophytes.     

内生条纹拟盘多毛孢发酵液中细胞毒活性成分研究

从条纹拟盘多毛孢Pestalotopsis virgatula发酵液中分离得到8个化合物,其结构分别被鉴定为：2-(1-甲氧基-1-H-吲哚-3-基)乙醇 (1),2-(1-甲氧基-1-H-吲哚-3-基)乙酸 (2),3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯 (3),麦角甾-4,6,8(14),22-四烯-3-酮 (4),对羟基苯乙醇 (5),邻苯二甲酸二异丁酯 (6),(E)-3-(4-羟基-3-甲氧苯基)败脂酸 (7) 和丁二酸 (8),化合物1–8均为首次从该菌种中分离得到。利用MTT法测试了化合物1 和2对5种人体肿瘤细胞的细胞毒活性,结果显示化合物1和2对5株肿瘤细胞株均具有一定选择性抑制活性。