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• Two tetrasubstituted α -pyrones were identified from the endophytic fungus Neurospora udagawae • Udagawanone B constitutes a rare example of a C-4 O -demethylated α -pyrone. • Their antimicrobial and cytotoxic activities are reported. Two new α -pyrone derivatives, udagawanones A (1) and B (2), along with the known compounds (Z)-4-hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid (3), isosclerone (4), cyclo -(L -Leu- L -Pro) (5), and cyclo -(L -Pro- L -Tyr) (6), were isolated from cultures of the endophyte Neurospora udagawae. Their structures were elucidated by extensive spectroscopic methods and single crystal X-ray diffraction. Both compounds feature oxidized functionalities at the C-2 position not previously observed in other tetrasubstituted α -pyrones from fungi. Compound 1 exhibited moderate antibacterial (vs. Staphylococcus aureus) and antifungal (vs. Rhodoturula glutinis) activities and cytotoxicity against KB3.1 cells. [ABSTRACT FROM AUTHOR]

Two new metabolites possessing the unusual 1-oxa-7-azaspiro[4.4]non-2- ene-4,6-dione core ( 2 , 3 ) along with the recently described pseurotin A 3 ( 1 ) were isolated from the pathogenic fungus Wilsonomyces carpophilus ( previously named Stigmina carpophila ). The producer organism was obtained from Prunus armeniaca collected in Iran and was identified by morphological and molecular phylogenetic methods. The structures of the isolated compounds were elucidated on the basis of extensive NMR spectroscopic analysis, high-resolution mass spectrometry and ECD analysis. The compounds were screened for their antimicrobial, cytotoxic, nematicidal and biofilm inhibition activities but, no significant effect was observed. To the best of our knowledge, this is the first report on the isolation of secondary metabolites produced by W. carpophilus . [ABSTRACT FROM AUTHOR]

Cornus mas (Cornelian cherry or European cornel) is a deciduous shrub with edible fruits that have medicinal benefits and is native to southern Europe and south-western Asia. This shrub grows wild in Arasbaran forests and the Qazvin region in Iran. In this study a new fruit rot disease was discovered on cornelian cherries in Arasbaran forests located in the north-west zone of Iran. Fruit samples were collected from severely infected C. mas trees in October 2017. Ten fungal isolates with the same morphological characteristics were recovered from symptomatic tissues on potato dextrose agar culture medium. The causal agent of the disease was identified as Pilidium lythri based on macro and micro morphological and molecular characterizations. In addition, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) fingerprintings were used to assess five P. lythri isolates (one isolate from each five parts of the forest) from cornelian cherry, five isolates from strawberry, and two isolates from olive. Based on the results, no polymorphism was observed among the isolates, denoting limited genetic variability. Pathogenicity assays confirmed P. lythri isolates to be pathogenic on cornelian cherry and strawberry fruits in vitro condition, irrespective of their origin. Based on the data presented in the current study, P. lythri isolates from different hosts showed a homogeneous genetic structure with no host preference. This is the first occurrence of P. lythri causing fruit rot on cornelian cherry in Iran and the world. • A new rot disease was observed on cornelian cherries in north-west zone of Iran. • The causal agent of the disease was identified as Pilidium lythri. • This is the first report of cornelian cherry rot caused by P. lythri worldwide. [ABSTRACT FROM AUTHOR]

During surveys on grapevines trunk diseases in vineyards at different localities in East and West Azerbaijan and Ardabil provinces, Iran, wood samples (two, three year-old cordons) were collected from grapevine showing decline symptoms, including leaf yellowing and necrosis, stunted growth, internal wood necrosis, black vascular discolouration. Nine fungal isolates with similar morphology were recovered from grapevines with decline symptoms in five different areas, which one-third of the isolates were recovered as the sole fungal agents. The identity of fungal isolates was determined as Quambalaria cyanescens based on the combination of cultural and morphological characteristics and DNA phylogeny. Pathogenicity trials based on excised shoot assay and potted grapevine under greenhouse conditions confirmed Q. cyanescens being pathogenic on grapevines; the isolates induced symptoms similar to those observed in naturally infected grapevines. Our findings confirm Q. cyanescens as a new fungal trunk pathogen of grapevine. Members of the genus Quambalaria are known to cause leaf spot, shoot blight and canker disease on Eucalyptus and its relative Corymbia. The current study is the first regarding pathogenicity of the Q. cyanescens on woody hosts; in previous studies Q. cyanescens has proven to be non-pathogenic to Corymbia spp. The host range, extent of geographical distribution and economic significance of this new pathogen on grapevine remains to be studied. Image 1 • Quambalaria cyanescens was recovered from grapevine with typical decline symptoms. • A polyphasic approach was employed to ascertain the identity of the causal agent. • Quambalaria cyanescens was confirmed to be pathogenic on grapevine. • We report Q. cyanescens as a new fungal trunk pathogen on grapevine, worldwide. • Pathogenicity of Q. cyanescens on woody hosts was confirmed for the first time. [ABSTRACT FROM AUTHOR]

Chemical analysis of extracts from cultures of the plant pathogenic fungus Cytospora sp. strain CCTU A309 collected in Iran led to the isolation of two previously unreported heptanedioic acid derivatives namely (2 R ,3 S) 2-hydroxy-3-phenyl-4-oxoheptanedioic acid (1) and (2 S ,3 S) 2-hydroxy-3-phenyl-4-oxoheptanedioic acid (2) as diastereomers, four previously undescribed prenylated p -terphenyl quinones 3 – 6 in addition to five known metabolites. Their structures were elucidated on the basis of extensive spectroscopic analysis and high-resolution mass spectrometry. For metabolites 1 and 2 , the absolute configurations at C-2 were deduced from comparison of the 1H NMR difference of their (S)- and (R)-phenylglycine methyl ester derivatives while the relative configurations were tentatively assigned by a J -based analysis and confirmed by comparison of 13C chemical shifts to literature data. The isolated compounds were tested for their cytotoxic, antimicrobial (including biofilm inhibition), antiviral, and nematicidal activities. While only moderate antimicrobial effects were observed, the terphenyl quinone derivatives 3 – 6 and leucomelone (10) exhibited significant cytotoxicity against the mouse fibroblast L929 and cervix carcinoma KB-3-1 cell lines with IC 50 values ranging from 2.4 to 26 μg/mL. Furthermore, metabolites 4–6 showed interesting antiviral activity against hepatitis C virus (HCV). Unlabelled Image [ABSTRACT FROM AUTHOR]

In the present study the population of fungi inhabiting metal contaminated soil samples from lead-zinc mining area was investigated, and their tolerance and biosorption capacity towards Cd, Pb, Zn and Cu were evaluated. Fungal species, including Acremonium persicinum , Penicillium simplicissimum , Seimatosporium pistaciae , Trichoderma harzianum , Alternaria chlamydosporigena and Fusarium verticillioides were isolated. Fungal tolerance was determined by measuring of the “Minimum Inhibitory Concentration”, after exposure to increasing concentrations of heavy metal chlorides. Among the test fungi, Trichoderma harzianum was the most tolerant against Cd, Pb and Cu. The Heavy metal content in the fungal biomass was quantified after combustion. The calculated total sorption of heavy metals showed that Acremonium persicinum and Penicillium simplicissimum had the highest accumulation of Zn and Cu, respectively. The data presented in this study should help to use the accumulation potential of some of those fungal species examined for bioremediation of contaminated soils. [ABSTRACT FROM AUTHOR]

From extracts of the plant associated fungus Chaetosphaeronema achilleae collected in Iran, a previously unreported isoindolinone named chaetosisoindolinone (1) and a previously undescribed indanone named chaetosindanone (2) were isolated in addition to five known metabolites, 2-(2-acetyl-3,5-dihydroxyphenyl) acetic acid (3), vulculic acid (4), 2-(2-acetyl-3-hydroxy-5-methoxyphenyl)acetic acid (5), curvulin (6), and curvulol (7). Their structures were elucidated on the basis of extensive spectroscopic analysis and high-resolution mass spectrometry. The isolated compounds were tested for their antimicrobial, anti-biofilm, and nematicidal activities. Compound 2 exhibited cytotoxicity against the human breast adenocarcinoma MCF-7 cells with an IC 50 value of 1.5 μg/mL. Furthermore, compounds 4 and 7 almost completely inhibited biofilm formation in Staphylococcus aureus at 256 μg/mL. Weak antimicrobial activities were also observed for some of the isolated compounds against Mucor hiemalis , Rhodoturula glutinis , Chromobacterium violaceum , and Staphylococcus aureus. Unlabelled Image • Chaetosphaeronema achilleae was isolated from Taxus baccata collected in Iran. • Seven polyketides including two previously undescribed derivatives were isolated. • Their structures were elucidated by extensive spectroscopic analysis and HRESIMS. • Some of the compounds exhibited cytotoxic and antibiofilm activities. [ABSTRACT FROM AUTHOR]