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AB023 is a complex of polyene antibiotics produced by an actinomycete, SD581, which was isolated from a Kenyan soil sample. The two main components, pentaene antibiotics AB023a and AB023b, have antifungal activity against some phytopathogenic fungi, particularly against Botrytis cinerea (MIC of 5 micrograms/ml).
The antimicrobial activities of twenty-two substances structurally related to staurosporine, aglycone in the indolocarbazole and bis-indole series were examined against Streptomyces chartreusis and Streptomyces griseus, Bacillus cereus, Escherichia coli, Candida albicans and Botrytis cinerea. Inhibition of sporulation was examined also on the two species of Streptomyces. Unlike literature reports for efficient protein kinase inhibitors, staurosporine and K-252a, no evident correlation could be found either between protein kinase inhibitory potencies and inhibition of sporulation of the Streptomyces species, or protein kinase inhibitory potencies and growth of all microorganisms tested. A weak activity against C. albicans was observed for the chloro-indolocarbazole compounds as already reported for structurally related substances from the cyanobacterium Tolypothrix tjipanasensis.
New compounds, structurally related to the potent protein kinase C inhibitor staurosporine, and substituted on the imide nitrogen with a functional group bearing a labile hydrogen (hydroxymethyl, amino, hydroxy), were synthesized. Their in vitro inhibitory potencies towards protein kinase C and protein kinase A showed that N-hydroxymethyl and N-hydroxy substitution, unlike alkyl substitution, can provide efficient protein kinase C inhibitors. The antimicrobial activities of these new compounds against Streptomyces chartreusis and Streptomyces griseus, Bacillus cereus, Escherichia coli, Candida albicans and Botrytis cinerea were examined. They proved to be inactive against E. coli and two fungi. The results suggest that there is no link between in vitro inhibition of protein kinase C and inhibition of growth and sporulation of the two Streptomyces tested. Unlike indolocarbazole maleimides, bis-indole maleimides are active against the two Streptomyces species.
An antifungal bacterial strain, isolated from a greenhouse soil sample, inhibits growth of microflora nearby. It was selected for further studies of bacterial antifungal properties. This isolate was identified as a Pseudomonas sp. based on carbohydrate utilization, and other biochemical and physiological tests. Petri plate assay revealed that the Pseudomonas sp. exhibited antifungal activity against the plant pathogens, Pythium ultimum, Rhizoctonia solani, Phytophthora capsici, Botrytis cinerea and Fusarium oxysporum. Using direct inhibition bioassay on TLC plates after ethyl acetate extraction of the culture filtrate, we correlated antifungal activity with production of antifungal compounds. An antifungal antibiotic was isolated from the culture filtrate and was identified as N-butylbenzenesulphonamide. ED50, values of the N-butylbenzenesulphonamide against P. ultimum, P. capsici, R. solani, and B. cinerea were 73, 41, 33 and 102 ppm, respectively.
Chaetoatrosin A, a novel chitin synthase II inhibitor, was isolated from the culture broth of fungus F449, which was identified as Chaetomium atrobrunneum F449. Chaetoatrosin A was purified by solvent partition, silica gel, ODS, preparative TLC, and Sephadex LH-20 column chromatographies, consecutively. The structure of chaetoatrosin A was assigned as 1,8-dihydroxy-3(2-hydroxypropionyl)-6-methoxynaphthalene on the basis of various spectroscopic analyses including UV, IR, mass spectral, and NMR. Its molecular weight and formula were found to be 262 and C14H14O5, respectively. ,Chaetoatrosin A inhibited chitin synthase II by 50% at the concentration of 104 microg/ml in an enzyme assay system. This compound showed antifungal activities against Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Cryptococcus neoformans and Trichophyton mentagrophytes.
Stilbenes are natural compounds occurring in a number of plant families, including Vitaceae and (within this family) Vitis vinifera L., which is the most important species grown worldwide for grape and wine production. Stilbenes (resveratrol and viniferins) are present in grapevine as constitutive compounds of the woody organs (roots, canes, stems) and as induced substances (in leaves and fruit) acting as phytoalexins in the mechanisms of grape resistance against certain pathogens. Resveratrol (3, 5, 4'-trihydroxystilbene) was also detected in wine and it was thought to be the active principle of red wines that were shown to reduce heart diseases. This paper reviews data, obtained by the Viticulture Institute of the Catholic University at Piacenza and taken from the literature, on some aspects of stilbene physiology in grapevine and on their relation to resveratrol wine levels. Constitutive stilbene contents of woody organs are reported, as well as the possible role of cluster stems as a source of resveratrol for wine. The accumulation of stilbenes in grape berries infected by grey mould (Botrytis cinerea Pers.) has been investigated and the effects of environmental factors on resveratrol grape and wine levels will be discussed. An unidentified new hydroxystilbene was detected in wine.
Our knowledge in aerobiology has considerably increased in the last 20 years due to new trapping methods. The use of volumetric spore traps permits to accurately analyze the particles suspended in the air and their evolution, while the deposition method gives an incomplete picture of the real air content. The air microflora changes considerably during 24 h: some groups of spores occur in the morning, others in the afternoon and yeast-like organisms during the night. The most common fungi in the atmosphere are Cladosporium sp., Sporodbolomyces considerably increase (20-10(3) times) the number of spores released in the atmosphere. Aspergillus flavus, thermophilic actinomycetes, Botrytis cinera and Didymella exitialis are cited as examples.
Microbial contamination of terrestrial hydroponic plant-growing systems provides an effective analogue for studying microbial contamination issues for space-based advanced life support (ALS) systems. If aggressive root or foliar pathogens are introduced into ALS hydroponic systems, severe epidemics are probable. Greater than 80% of the reported outbreaks of root pathogens in terrestrial hydroponic systems describe epidemics caused by fungal species of Fusarium, Phytophthora, and Pythium. However, it is likely that a comprehensive sanitation and quarantine program for space-based ALS modules will prevent contamination by Phytophthora and Pythium spp. because these pathogens are general soilborne. However, Fusarium spp. are typically airborne, can grow saprophytically on diverse substrates, and have been common contaminants of American spacecraft. If comprehensive sanitation and quarantine programs are established for space-based ALS modules, then the threat of pathogen introductions into these systems will be significantly mitigated. Microbial contamination studies in spacecraft over the last 30 years indicate that a high diversity of bacteria, fungi, and actinomycetes are commonly carried on board probably via clothing, equipment, air currents during spacecraft handling and loading, food, and the astronauts themselves. Species of Alternaria, Aspergillus, Botrytis, Candida, Cephalosporium, Cladosporium, Fusarium, Mucor, Penicillium, Phoma, and Trichoderma were the most prevalent fungi recovered, and species of Bacillus, Escherichia, Klebsiella, Micrococcus, Pseudomonas, Staphylococcus, and Streptococcus were the most prevalent bacteria recovered from spacecraft. Most of these genera contain species that have been reported as plant pathogens. Strict quarantine procedures were not effective in preventing contamination of spacecraft during these missions. Research must be initiated to better understand how microorganisms interact with plants and animals in microgravity environments because microbial contamination of spacecraft and ALS modules cannot be avoided. An integrated pest management (IPM) program likely will be developed for managing plant disease outbreaks in space-based ALS systems.
Farmers are known to be at high risk from the development of occupational airway disease. The first stage of the European farmers' study has shown that pig farmers in Denmark and Germany, poultry farmers in Switzerland and greenhouse workers in Spain were at highest risk for work-related respiratory symptoms. Therefore, the aim of this study was to determine exposure levels at relevant farm workplaces. Dust and endotoxin levels as well as microbiological concentrations were determined in 213 crop and animal farming environments by personal sampling. The highest total dust concentrations were found in poultry houses in Switzerland with median concentrations of 7.01 mg/m(3). The median airborne endotoxin concentrations in total dust ranged between 0.36 ng/m(3) in Spanish greenhouses and 257.58 ng/m(3) in poultry houses in Switzerland. Likewise, the highest median concentrations of total (2.0 x (7) cells/m(3)) and active fungi (4.4 x (5) cfu/m(3)) have been found in Swiss poultry houses. The predominant fungus taxa discovered in poultry houses were Eurotium spp. and thermophilic fungi. Cladosporium and Botrytis were mainly detected in greenhouses. The exposure level found in this study might put the farmers at risk from respiratory diseases.
A series of N-alkyl-N'-(4-diazo-5-pyrazolyl)-ureas (4) was thermally and photochemically converted into pyrazolo [3,4-d][1,2,3]triazole derivatives (5,6) and 5-alkylaminopyrazolo[3,4-d]oxazoles (7) respectively. The products were tested for in vitro antifungal activity against Fusarium culmorum, Botrytis cinerea, Phoma betae, Pythium ultimum, Sclerotinia minor and Rhizoctonia solani. The MIC and ED50 values of compound (6) against some of the test fungi were comparable to those of the reference fungicides iprodione and mancozeb.
The study of the root-associated microbial complexes of affected and healthy rose plants of two cultivars (Grand gala and Royal velvet) grown in a greenhouse showed that the biomass of eukaryotic microorganisms in the rhizoplane and rhizosphere of healthy rose plants and in the surrounding soil was considerably lower than in the same loci of affected plants. In contrast, the biomass of root-associated prokaryotic microorganisms was higher in the case of healthy than in the case of affected rose plants. The root-associated bacterial complexes of both affected and healthy rose plants were dominated by the genera Arthrobacter, Rhodococcus, and Myxobacterium and did not contain phytopathogenic bacteria. The root-associated fungal complex of healthy roses was dominated by fungi of the genus Trichoderma, whereas that of the affected rose plants was dominated by the species Aureobasidium microstictum. The affected cane cuttings and cankers occurring on affected canes were found to contain Coniothyrium fuckelii (the causal fungus of rose stem canker) and sclerotia of Botrytis cinerea (the causal fungus of gray rot). The micromycete complex of healthy rose plants was not so diverse as was the micromycete complex of affected rose plants.
Cauliflower (Brassica oleracea var. botrytis L.) and cabbage (B. oleracea var capitata L.) are two varieties of species B. oleracea. Cauliflower BobCAL gene losses the original function due to its terminated mutation while cabbage BoCAL gene has the complete function. We obtained cauliflower plants transgenic for BoCAL gene using Arobacterium-mediated transformation. Genetic analysis of T2 generation indicated that all cauliflower plants transgenic for BoCAL failed to form curd and produced the green, loosed inflorescences composed of flower buds instead, demonstrating that cauliflower BobCAL was complemented by cabbage BoCAL, and thus transgenic cauliflower lost the ability to form curd. Selfing of these transgenic plants gave rise to the similar inflorescence phenotype of T3 plants except 15 days delay of inflorescence appearance compared with the plants of T1 generation. When transgenic cauliflower was crossed with wild-type cauliflower, the progenies formed the curd with a few of flower buds, and they delayed inflorescence onset till 135 days after sowing.
House dust is an important source of different toxic metabolites as well as allergens, including those of fungal origin, in the indoor environment. A bio-assay employing 1-day-old chick tracheas was used to characterize airway effects of 2-butanone and dimethylsulphoxide (Me2SO) extracts of 23 dust samples collected from water damaged (13) and control (10) Danish schools. Direct microscopical analysis of samples, followed by cultivation on dichloran 18 % glycerol agar at 25 degrees C for 10 days to establish their mycoflora, was performed. The in vitro ciliostatic potential of the chloroform-extractable endo- and exometabolites of 41 representative fungal isolates was determined. Nine dust extracts in 2-butanone (2 from damp rooms) or 10 (6) in Me(2)SO showed some ciliostatic activity in the 3-days' experiment. Fungal composition of dust from buildings with leakage was almost identical with that from undamaged houses, as well as the fungal colony counts from the damp schools and the control samples. Aspergillus spp. were prevalent in the samples - 31 or 40 % of all fungi, followed by Penicillium spp. and Cladosporium cladosporioides. Alternaria spp., Chaetomium spp., Mucor spp., Mycelia sterilia, Paecilomyces variotii, Rhizopus sp., Ulocladium sp. and yeasts were each isolated in less than 8 % of the fungal content. No Aspergillus flavus isolate (8 in total) was aflatoxigenic,em>in vitro. Alternaria spp., Aspergillus spp., Botrytis cinerea, Penicillium spp., C. cladosporioides, Chaetomium spp. and Ulocladium sp.; in total, 88 % of all fungi tested, produced ciliostatically active metabolites. These toxigenic strains were also present in 4 dust samples from controls and 5 dust samples from water damaged buildings. Extracts of these dust samples were also toxic in bioassay. There were bio-detectable concentrations (10-20 microg of extracts/ml of the organ culture medium) of toxic compounds in house dust. Contribution of fungal metabolites to its toxic effect should be studied further.
The autoregulation of conidium germination in phytopathogenic micromycetes of the genera Fusarium, Botrytis, and Bipolaris was studied. It was shown that Trichoderma longibrachiatum was less competitive than Fusarium oxysporum after their simultaneous inoculation but inhibited the phytopathogen growth in the case of earlier introduction. In the latter case, no autoinhibition of the germination of F. oxysporum conidia occurred; moreover, cooperative effect was observed, i.e., the number of germinated F. oxysporum conidia increased with an increase in their density.
BACKGROUND: The prevalence of respiratory allergy to fungi spores (FS) is not precisely known but is estimated at 20-30% of atopic patients. There are no aerobiological records, necessary for respiratory allergy diagnosis and treatment, in Thessaloniki and generally in Greece. AIM: Creation of a database on FS circulation and investigation of skin sensitivity (SS) of asthmatics by using skin prick tests (SPT). MATERIAL AND METHODS: Daily records and identification of 15 airborne FS species were conducted, using a Burkard trap during 1987-2001. SS to 5 most common FS extracts was investigated, by using SPT in a total of 1311 asthmatics with atopy, submitted to the Out-Patient Clinic of Asthma (Pulmonary Dept, Aristotle Univ, Thessaloniki) in 1990-2001. RESULTS: The FS recorded in the 15-year period were as follows: Cladosporium spp. (72.2%), Alternaria spp. (9.8%), Ustilago spp. (8.1%), Ascospores (2.7%), Agrocybe spp. (1.5%), Helminthosporium spp. (1.4%), Leptosphaeria spp (1.2%), Agrogybe spp. (1.1%), whereas the species Botrytis, Stemphylium, Pleospora, Nigrospora, Epicoccum. Fusarium, Torula and Phoma presented concentrations <1%. The highest numbers of airborne FS were recorded during summer. Positive skin reaction to FS was observed in 421 (32%) patients of the 1311 asthmatics. Positive skin reaction to Altemaria species was observed in 177 patients (13.5%), in 98 (7.4%) to Cladosporium, 65 (5%) to Aspergillus, 45 (3.4%) to Fusarium and 36 (2.7%) to Rhizopus. FS sensitivity is much more frequent in younger men. CONCLUSIONS: For the first time in Thessaloniki-Greece, 15 allergenic FS species circulation has been recorded for the last 15 years. SS was more frequently detected for the species of Alternaria, Cladosporium and Aspergillus.
The aim of the study was to analyse the relationship between meteorological conditions and Alternaria and Cladosporium spore concentrations in the air of Zagreb in August 2002 and August 2003. These months were chosen because they represented climatic extremes. A 7-day VPPS 2000 Hirst volumetric pollen and spore trap was used for spore sampling. Spores marked as 'others' (ascospores, basidiospores, Epicoccum, Ustilago, Pithomyces, Helminthosporium, Stemphylium, Torula, Botrytis, Didymella) were found to have predominated in the month of August in both 2002 and 2003 with 91.1% and 70.5%, respectively. Because of favourable weather conditions (higher air temperature and minimal precipitation) in August 2003, the concentrations of Alternaria and Cladosporium spores were 3.4-fold those recorded in the same month in 2002. Also, the peak daily concentrations of these spores were measured on days without precipitation and with higher air temperature. Intradiuranal variation in the Alternaria and Cladosporium spore concentrations was identical in 2002 and 2003 (lowest in 2-hour interval between 06:00-08:00, and highest between 10:00-12:00). In spite of the three-fold increase in the Cladosporium spore concentration in August 2003, the borderline concentration of 3,000 spores/m3 air that is associated with the occurrence of allergic reactions was only exceeded on a single day. Air concentration of Alternaria spores exceeded borderline value of 100 spores/m3 air on as many as 17 days, suggesting that at that time of the year the risk of allergic reaction was only present in individuals allergic to this spore type.
This study is the first communication about the repercussion of several phytosanitary treatments in three different training systems, differently managed in foilage, in relation to the usual phytopatologies: botrytis, acid rot, grape mildew and oldium. Particular attention to residuals of the products supplied on the foilage and present in ground and wine is paid. The considered foilage management systems are among those more spread and effective ones for a good quality wine production for Cabernet Sauvignon variety (clone R5). 11. Cordon Spur of Conegliano (C.S.C); 12. Simple Free Espalier Curtain (S.C.S.L); 13. Lyra (Lyra). The phytosanitary interventions for the foilage management systems have been compared between the company's ordinary plan and one with various and numerous active principles. The CG-ECD with Multiresidual analysis has determined the active principles residuals in the ground and in the wines. The characteristics of the wines have been determined by physical- chemical analysis; their organoleptic quality has been valued by panels of producers, oenologists, consumers and restaurant staff. The results point out a difference among the trials for the different presence of residuals. The foilage management justifies the diversity of the analytical composition of the wines. There is a substantial uniformity of judgements for the organoleptic quality. In conclusion, in this prove the judgement on the economic quality highlights the uselessness of the use of more incisive and radical active principles.
In the present work, we performed in vitro testing of 33 species of fungi of the subdivision Deuteromycotina isolated from water and sediment of the Kolubara River for antagonistic action towards 11 species of pathogenic bacteria. Of gram-negative bacteria, the species most sensitive to metabolic fluid of the fungi were Proteus mirabilis, Salmonella enteritidis, and Shigella sonnei, while the most resistant were Klebsiella pneumoniae and Salmonella typhimurium. Of gram-positive bacteria, the most sensitive species was Staphylococcus aureus, while the most resistant was Enterococcus faecalis. Of the tested fungi, Penicillium canescens, P. simplicissimum, P. thomii, Aspergillus fumigatus, A. ochraceus, and Fusarium culmorum exerted inhibitory action on the greatest number of species of pathogenic bacteria, while Verticillium lateritium, V. tenerum, Phoma humicola, and Botrytis cinerea had an inhibiting effect on the least number of species.