WorldWideScience
 
 
1

Santonian To ?Earliest Campanian (Late Cretaceous) Fungi from the Milk River Formation, Southern Alberta, Canada  

Science.gov (United States)

... its infancy. However, the geological record of many fossil fungi is well established (Elsik, 1996; Kalgutkar and Jansonius, ... 1988). A comprehensive account of the history of fossil fungi, and the impor...

5

Stabilization of lignin peroxidases in white rot fungi by tryptophan.  

UK PubMed Central (United Kingdom)

Supplementation of various cultures of white rot fungi with tryptophan was found to have a large stimulatory effect on lignin peroxidase activity levels. This enhancement was greater than that observed...Full Text Available

1997-07-01

6

Nylon biodegradation by lignin-degrading fungi.  

UK PubMed Central (United Kingdom)

The biodegradation of nylon by lignin-degrading fungi was investigated. The fungus IZU-154 significantly degraded nylon-66 membrane under ligninolytic conditions. Nuclear magnetic resonance analysis...Full Text Available

1997-01-01

7

Microbial Anaerobic Demethylation and Dechlorination of Chlorinated Hydroquinone Metabolites Synthesized by Basidiomycete Fungi  

UK PubMed Central (United Kingdom)

The synthesis and degradation of anthropogenic and natural organohalides are the basis of a global halogen cycle. Chlorinated hydroquinone metabolites (CHMs) synthesized by basidiomycete fungi and present...Full Text Available

2004-01-01

8

High genetic variability and low local diversity in a population of arbuscular mycorrhizal fungi  

UK PubMed Central (United Kingdom)

Arbuscular mycorrhizal fungi (AMF) are ecologically important root symbionts of most terrestrial plants. Ecological studies of AMF have concentrated on differences between species; largely assuming...Full Text Available

2004-02-24

9

Anthracenedione Derivatives as Anticancer Agents Isolated from Secondary Metabolites of the Mangrove Endophytic Fungi  

UK PubMed Central (United Kingdom)

In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403)...Full Text Available

10

Analysis of Quantitative Interactions between Two Species of Arbuscular Mycorrhizal Fungi, Glomus mosseae and G. intraradices, by Real-Time PCR  

UK PubMed Central (United Kingdom)

Arbuscular mycorrhizal fungi (AMF) are obligate biotrophs, known to play an important role in ecological processes. Conventional light microscopy is the most common method used to detect their presence...Full Text Available

2006-06-01

12

Biodehalogenation.  

UK PubMed Central (United Kingdom)

Haloorganic biocides are widely employed as soil fumigants to combat the destructive action of plant parasitic nematodes and fungi. These substances are dehalogenated by soil organisms, principally...Full Text Available

1977-12-01

13

At the Root of the Wood Wide Web  

UK PubMed Central (United Kingdom)

Arbuscular mycorrhizal (AM) fungi are mutualistic symbionts living in the roots of 80% of land plant species, and developing extensive, below-ground extraradical hyphae fundamental for the uptake of...Full Text Available

2006-01-01

14

Apoplastic invertases  

UK PubMed Central (United Kingdom)

The mutualistic interaction of plants with arbuscular mycorrhizal (AM) fungi is characterized by an exchange of nutrients. The plant provides sugars in the form of hexoses to the heterotrophic fungus...Full Text Available

2008-05-01

15

Agni’s fungi: heat-resistant spores from the Western Ghats, southern India  

British Library Electronic Table of Contents (United Kingdom)

This study concerns the thermotolerance of spores of mesophilic fungi isolated from a tropical semi-arid habitat subject to dry season fire in the Western Ghats, southern India. Among 25 species of Ascomycota isolated from leaf litter, nine were able to grow after incubation in a drying oven for 2h at 100degreeC; the spores of two of these species survived 2h incubation at 110degreeC, and one survived exposure to 115degreeC for 2h. The range of thermotolerance among mesophilic fungi isolated from the leaf litter was surprising: filamentous fungi from other habitats, including species that colonize scorched vegetation after fires and thermophilic forms occurring in self-heating plant composts, cannot survive even brief exposure to such high temperatures. It is possible that the exceptional ...

2011-01-01

16

The microbiology of forest soils: a literature review  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the activities of two major groups of forest soil microorganisms, the bacteria and the fungi. Special attention is paid to their participation in the decay of major forest litter substrates, including leaves, branches and roots. The influence of bacteria and fungi in symbiotic associations with woody plant roots upon the cycles of carbon and nitrogen is described. The impacts of certain forest mamagement alternatives are assessed in terms of the creation of elimination of suitable environments for the activity of soil microorganisms. A bibliography is included. 507 refs., 1 tab.

1982-01-01

17

Fungal Parasites of the Potato Cyst Nematode Globodera rostochiensis: Isolation and Reinfection.  

Science.gov (United States)

Fungal parasitism of eggs of the potato cyst nematode Globodera rostochiensis was Cladosporium cladosporoides did not infect eggs. No chitinase activity was found in these fungi, but protease activity was recorded in all. Growth of the fungi in cysts did not influence the number of physiologically disordered eggs. PMID:19287764

1990-10-01

18

The endophytic fungi from wheat (Triticum aestivum L.)  

British Library Electronic Table of Contents (United Kingdom)

In order to study the species composition of endophytes from wheat healthy plants in Buenos Aires Province (Argentina) and to determine their infection frequencies from leaves, stems, glumes and grains, wheat plants were collected from five cultivars at five growth stages from crop emergence to harvest. A total of 1,750 plant segments (leaves, stems, glumes and grains) were processed from the five wheat cultivars at five growth stages, and 722 isolates of endophytic fungi recovered were identified as 30 fungal genera. Alternaria alternata, Cladosporium herbarum, Epicoccum nigrum, Cryptococcus sp., Rhodotorula rubra, Penicillium sp. and Fusarium graminearum were the fungi that showed the highest colonization frequency (CF%) in all the tissues and organs analysed. The number of taxa isolated...

2007-01-01

19

Effects of fungicides on endophytic fungi and photosynthesis in seedlings of a tropical tree, guarea guidonia (meliaceae)  

International Nuclear Information System (INIS)

Endophytes are microorganisms that live within healthy plant tissues, and include fungi and bacteria. They can be mutualists, comensals or even latent pathogens. Presence of these endosymbionts may affect host physiology, for example by consuming products of photosynthesis (endophytes are heterotrophs) or producing toxic metabolites. In this work two fungicides were used to eliminate fungal endophytes from seedlings of guarea guidonia. light saturated photosynthesis (Amax) was measured in endophytefree plants and compared with control plants. Each fungicide killed different fungal endosymbionts. phomopsis was more susceptible to benomyl while colletotrichum was more susceptible to propiconazole. Although suggestive, values of Amax were not significantly different for each treatment compared with control plants. No prediction can be made at this point about the final outcome of a given plantendophytic fungi interaction

2005-12-01

20

The Genetic Basis of Cellular Morphogenesis in the Filamentous Fungus Neurospora crassa  

UK PubMed Central (United Kingdom)

Cellular polarity is a fundamental property of every cell. Due to their extremely fast growth rate (≥1 μm/s) and their highly elongated form, filamentous fungi represent a prime example...Full Text Available

2003-11-01

 
 
 
 
21

Succession of Indigenous Pseudomonas spp. and Actinomycetes on Barley Roots Affected by the Antagonistic Strain Pseudomonas fluorescens DR54 and the Fungicide Imazalil  

UK PubMed Central (United Kingdom)

In recent years, the interest in the use of bacteria for biological control of plant-pathogenic fungi has increased. We studied the possible side effects of coating barley seeds with the antagonistic...Full Text Available

2001-03-01

22

Rapid Detection of Ophiostoma piceae and O. quercus in Stained Wood by PCR  

UK PubMed Central (United Kingdom)

A rapid, sensitive, and simple method was developed to detect the sapstain fungi Ophiostoma piceae and O. quercus in stained wood. By using microwave heating for DNA...Full Text Available

1999-01-01

23

Pseudomonas aeruginosa-Candida albicans Interactions: Localization and Fungal Toxicity of a Phenazine Derivative?  

UK PubMed Central (United Kingdom)

Phenazines are redox-active small molecules that play significant roles in the interactions between pseudomonads and diverse eukaryotes, including fungi. When Pseudomonas aeruginosa...Full Text Available

2009-01-01

24

New Species of the Late Cenozoic Fungal form-Genus Mediaverrunites Jarzen & Elsik 1986 Ex Nandi & Sinha 2007  

Science.gov (United States)

... Wrenn. References CitedBanerjee, S., and Nandi, B. 1992 Fossil fungi from Miocene sediments of Mizoram and their environmental ... ...

25

Fungal spores: hazardous to health?  

UK PubMed Central (United Kingdom)

Fungi have long been known to affect human well being in various ways, including disease of essential crop plants, decay of stored foods with possible concomitant production of mycotoxins, superficial...Full Text Available

1999-06-01

26

Characterization of Airborne Microbial Communities at a High-Elevation Site and Their Potential To Act as Atmospheric Ice Nuclei?  

UK PubMed Central (United Kingdom)

Bacteria and fungi are ubiquitous in the atmosphere. The diversity and abundance of airborne microbes may be strongly influenced by atmospheric conditions or even influence atmospheric conditions themselves...Full Text Available

2009-08-01

27

Buoyant Densities and Dry-Matter Contents of Microorganisms: Conversion of a Measured Biovolume into Biomass  

UK PubMed Central (United Kingdom)

Several isolates of bacteria and fungi from soil, together with cells released directly from soil, were studied with respect to buoyant density and dry weight. The specific volume (cubic centimeters...Full Text Available

1983-04-01

28

An Efficient Fungal RNA-Silencing System Using the DsRed Reporter Gene?  

UK PubMed Central (United Kingdom)

In filamentous fungi, RNA silencing is an attractive alternative to disruption experiments for the functional analysis of genes. We adapted the gene encoding the autofluorescent DsRed protein as a reporter...Full Text Available

2007-02-01

29

[The metabolites of cyclic peptides from three endophytic mangrove fungi].  

Science.gov (United States)

Nine secondary metaboites of cyclic peptide were isolated from three mangrove endophytic fungi Paecilomyces sp. (treel-7), 4557,ZZF65. They were viscumamide(1),cyclo(Pro-Iso)(2),cyclo(Phe-Gly)(3),cyclo(Phe-Ana)(4),cyclo(Gly-Pro) (5),cyclo(Gly-Leu)(6), cyclo(Trp-Ana)(7),neoechinulin A(8),cyclo(Pro-Thr)(9). The compounds 1,7,8,9 were firstly isolated from marine fungus. PMID:18422185

2007-12-01

30

Field scale evaluation of a hybrid bioremediation and phytoremediation process for the treatment of hydrocarbon contaminated soil (BIOPHYTO")"  

Environmental Research Database

DescriptionThis project aims to develop a hybrid bioremediation/phytoremediation process for sustainable in- situ treatment of hydrocarbon contaminated soils, centred on 3 tenets: 1) Application of wood-chip derived compost enriched with white rot fungi for primary bioremediation; 2) Growth of pre-selected plant species for secondary phytoremediation; 3) Use of stress- adapted mycorrhizal fungi to maximise plant performance. A multidisciplinary approach is essential to optimise bioremediation for the trea [continued...

2008-01-14

31

Simulated nitrogen deposition affects wood decomposition by cord-forming fungi.  

Science.gov (United States)

Anthropogenic nitrogen (N) deposition affects many natural processes, including forest litter decomposition. Saprotrophic fungi are the only organisms capable of completely decomposing lignocellulosic (woody) litter in temperate ecosystems, and therefore the responses of fungi to N deposition are critical in understanding the effects of global change on the forest carbon cycle. Plant litter decomposition under elevated N has been intensively studied, with varying results. The complexity of forest floor biota and variability in litter quality have obscured N-elevation effects on decomposers. Field experiments often utilize standardized substrates and N-levels, but few studies have controlled the decay organisms. Decomposition of beech (Fagus sylvatica) blocks inoculated with two cord-forming basidiomycete fungi, Hypholoma fasciculare and Phanerochaete velutina, was compared experimentally under realistic levels of simulated ...

2011-07-01

32

Dating divergences in the Fungal Tree of Life: review and new analyses.  

Science.gov (United States)

The collection of papers in this issue of Mycologia documents considerable improvements in taxon sampling and phylogenetic resolution regarding the Fungal Tree of Life. The new data will stimulate new attempts to date divergences and correlate events in fungal evolution with those of other organisms. Here, we review the history of dating fungal divergences by nucleic acid variation and then use a dataset of 50 genes for 25 selected fungi, plants and animals to investigate divergence times in kingdom Fungi. In particular, we test the choice of fossil calibration points on dating divergences in fungi. At the scale of our analysis, substitution rates varied without showing significant within-lineage correlation, so we used the Langley-Fitch method in the R8S package of computer programs to estimate node ages. Different calibration points had a dramatic effect on estimated divergence dates. The estimate for the age of the ...

33

Effect of gamma radiation on the survival of fungal and actinomycetal florae contaminating medicinal plants  

Energy Technology Data Exchange (ETDEWEB)

This study evaluates the effect of gamma radiation on the viability of fungi and actinomycetes that contaminate medicinal plants. The relationship between the total lipids of some fungi and actinomycetes and their sensitivity to gamma radiation is also investigated. The data reveal that the viable counts of these florae decrease approximately exponentially with the radiation dose, the effective dose for the elimination of these microorganisms being about 5 kGy for all the medicinal plants under study. Response of pure cultures of fungi and actinomycetes isolated from medicinal plants to increasing absorbed doses of gamma radiation indicate that an increase in radioresistance is in the following order: Streptomyces rimosus, Fusarium solani, Nocardia kuroishii. F. oxysporum, A. fumigatus, A. flavus, A. parasiticus and A. ochraceus. The total lipid contents of molds and actinomycetes have been reported to be increased by ...

1997-01-01

34

Infection by mycotoxigenic fungal species and mycotoxin contamination of maize grain in Umbria, central Italy  

British Library Electronic Table of Contents (United Kingdom)

Surveys were carried out in 2006 and 2007 in Umbria (central Italy) to evaluate the presence of mycotoxigenic fungi and mycotoxins in maize grain sampled at harvest. Fusarium spp., were the most abundant species detected in maize kernels, followed by Aspergillus species of sections Flavi and Nigri and by Penicillium spp. Among Fusarium species, F. verticillioides was the most prevalent species, as detected by PCR directly on the kernels and on the fungi isolated from the kernels, followed by F. proliferatum and F. subglutinans. Fumonisins were the predominant mycotoxins with values, on average, of 4.3 and 5.7mgkg-1, in 2006 and 2007, respectively, with a maximum of 76.3mgkg-1 in the second year. Deoxynivalenol ranged from 0.2 to 3.98mgkg-1 in 2006 (average 1.04mgkg-1) and from undetectable...

2011-01-01

35

Endophytic fungus Trichothecium roseum LZ93 antagonizing pathogenic fungi in vitro and its secondary metabolites  

British Library Electronic Table of Contents (United Kingdom)

The endophytic fungus Trichothecium roseum LZ93 from Maytenus hookeri was found to antagonize other pathogenic fungi in vitro. To identify which compound contributed substantially to the antagonism, we fermented the strain and purified its fermentation products. Eleven compounds were obtained, including two trichothecenes, five rosenonolactones, two cardiotonic cyclodepsipeptides, and two sterols. Compound 11?-hydroxyrosenonolactone (1) was assigned according to 1D and 2D-NMR data for the first time. At the same time, the 1H and 13C-NMR assignments for 6?-hydroxyrosenonolactone (2) were revised. Of all of them, only trichothecin (6) showed strong antifungal activity. Based on our observations of the antagonistic activity and the other experimental results, we suggest that the antifungal co...

2010-01-01

36

Biosorption of heavy metals on fungal biomass  

Energy Technology Data Exchange (ETDEWEB)

A method of using fungi in removing heavy metal from wastewater was discussed. Fungi for this purpose can be obtained inexpensively, and on a constant basis from industrial fermentation processes. The biosorption of lead, cadmium and nickel on fungal stock cultures, was investigated. In these experiments, the fungal stock used was Aspergillus niger and Rhizopus stolonfier. Alkali pre-treatment of the fungal biomass improved the metal biosorptive capacity in comparison to live cells. The effect of alkali treatment, however, varied,showing highest biosorptive capacity for lead and least for nickel. Results showed that metal biosorption of metallic ions increased with an increase in pH from 3.2 to 4.0. Equilibrium times of five hours were observed for the biosorption of lead and cadmium, while the equilibrium time for nickel was three hours. 10 refs., 3 tabs., 7 figs.

1996-09-01

37

Anthracenedione derivatives as anticancer agents isolated from secondary metabolites of the mangrove endophytic fungi.  

Science.gov (United States)

In this article, we report anticancer activity of 14 anthracenedione derivatives separated from the secondary metabolites of the mangrove endophytic fungi Halorosellinia sp. (No. 1403) and Guignardia sp. (No. 4382). Some of them inhibited potently the growth of KB and KBv200 cells, among which compound 6 displayed strong cytotoxicity with IC(50) values of 3.17 and 3.21 microM to KB and KBv200 cells, respectively. Furthermore, we demonstrate that the mechanism involved in the apoptosis induced by compound 6 is probably related to mitochondrial dysfunction. Additionally, the structure-activity relationships of these compounds are discussed. PMID:20479985

2010-04-23

38

Metabolomic analysis of the plant pathogenic fungi Fusarium graminearum and Fusarium culmorum  

Environmental Research Database

DescriptionThis project is part of the BBSRCs special initiative on plant and microbial metabolomics. The project will primarily focus on the trichothecene mycotoxin producing Ascomycete fungus Fusarium graminearum (Fg) which causes ear blight disease of small grain cereals. The project aims to explore the metabolome of various wild-type and single gene deletion Fg strains and to compare some of these with the identical gene mutation in the budding yeast, S. cerevisiae (Sc) and the saprophytic filamentous [continued...

2008-01-31

39

Biological solubilization of coal in aqueous and nonaqueous media  

Energy Technology Data Exchange (ETDEWEB)

Current investigations into the biological solubilization of coal with microorganisms focus on the production of solubilizing activity in fungi. Test organisms for this work include a species of the yeast Candida previously isolated from a lignite outcrop, and P. chrysosporium, a filamentous higher fungus which has played a major role in lignin biodegradation research. The studies described are primarily exploratory in nature, and are fundamental to the design of more sophisticated inquiries into the physiology of fungal coal solubilization.

1987-01-01

40

Aflatoxin-producing Aspergillus spp. and aflatoxin levels in stored cassava chips as affected by processing practices  

DEFF Research Database (Denmark)

Cassava chips (cassava balls, and cassava pellets) are derived cassava products traditionally produced by farmers in sub-Saharan Africa following fermentation, and drying of fresh roots of cassava, and are widely consumed in Cameroon. Once produced, this food commodity can be stored for more than two months and contaminated by a wide array of harmful microbes. In order to assess persistence of toxigenic fungi in cassava chips, aflatoxin-producing fungi (Aspergillus flavus, Aspergillus nomius, and Aspergillus parasiticus) and aflatoxins were contrasted at regular intervals in home-stored cassava chips collected in two locations of southern Cameroon throughout a two-month monitoring period. Three hundred and forty-six isolates of aflatoxin-producing fungi were found to be associated with all samples. A. flavus contaminated more samples in both types of chips (267 isolates in 53 samples), followed by A. nomius (58 isolates in ...

2009-01-01

 
 
 
 
41

Study on upgrading of oil palm wastes to animal feeds by radiation and fermentation processing  

International Nuclear Information System (INIS)

Upgrading of oil palm empty fruit bunch (EFB), which is a main by-product of palm oil industry, to animal feeds by radiation pasteurization and fermentation was investigated for recycling the agro-resources and reducing the environmental pollution. The following results were obtained: 1) The necessary dose for pasteurization of EFB contaminated by various microorganisms including aflatoxin producing fungi was determined as 10 kGy. The chemical and biological properties of EFB were changed little by irradiation up to 50 kGy. 2) In the fermentation process, Pleurotus sajor-caju was selected as the most effective fungi and the optimum condition for fermentation was clarified. The process of fermentation in suspension was also established for the liquid seed preparation. 3) The digestibility and nutritional value of fermented products were evaluated as ruminant animal feeds and the mushroom can be produced as by-product. 4) The pilot plant named ...

2002-10-15

42

Potential anti fungal agents. Synthesis and activity of 2-alkylthiopyridine-4-carbothioamides  

Energy Technology Data Exchange (ETDEWEB)

A series of 2-alkylthiopyrine-4-carbothioamides were synthesized, and their anti-fungal potency was tested. The chemical structures were proved by infrared spectroscopy (IR) and {sup 1}H nuclear magnetic resonance ({sup 1}H-NMR) data and by elemental analysis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) assessment were used for the estimation of potential activity in vitro. The study comprising 21 clinical isolates of fungi showed that two compounds exhibited fair inhibitory activity against some yeasts and dermatophytes. Selective fungistatic activity against non-dermatophytes (MIC = 3.12-25.0 {mu}g/mL) was found also in another compound. None of the above compounds showed inhibitory activity against non-dermatophyte filamentous fungi. Microbiological activity of 2-alkylthiopyridine-4-carbothioamides appears to be mainly related to hydrophobicity of alkyl in position 2. (authors). 10 refs., 8 tabs.

1996-05-01

43

Immunity and tolerance to infections in experimental hematopoietic transplantation  

British Library Electronic Table of Contents (United Kingdom)

Resistance and tolerance are two types of host defense mechanisms that increase fitness in response to fungi. Several genetic polymorphisms in pattern recognition receptors, most remarkably Toll-like receptors (TLRs), have been described to influence resistance and tolerance to aspergillosis in distinct clinical settings. TLRs on dendritic cells pivotally contribute in determining the balance between immunopathology and protective immunity to the fungus. Epithelial cells also contribute to this balance via selected TLRs converging on indoleamine-2,3-dioxygenase (IDO). Studies in experimental hematopoietic transplantation confirmed the dichotomy of pathways leading to resistance and tolerance to the fungus providing new insights on the relative contribution of the hematopoietic/nonhematopoi...

2011-01-01

44

Antifungal activity of Glycyrrhiza glabra extracts and its active constituent glabridin  

British Library Electronic Table of Contents (United Kingdom)

Glabridin, an active constituent of Glycyrrhiza glabra roots, was found to be active against both yeast and filamentous fungi. Glabridin also showed resistance modifying activity against drug resistant mutants of Candida albicans at a minimum inhibitory concentration of 31.25-250 g/mL. Although the compound was reported earlier to be active against Candida albicans, but this is the first report of its activity against drug resistant mutants. Copyright Copyright 2009 John Wiley & Sons, Ltd.

2009-01-01

45

Determination of volatile metabolites originating from mould growth on wall paper and synthetic media.  

Science.gov (United States)

Microbial volatile organic compounds (MVOCs) emitted from the mould species Penicillium expansum, P. chrysogenum, Aspergillus versicolor, A. fumigatus, A. niger and Cladosporium cladosporoides were analyzed by means of solid phase microextraction (SPME) and GCMS. The mould species were cultivated on the synthetic agar dichloran chloramphenicol (DG 18) and on wet wall paper. The production of MVOCs was monitored over several weeks to detect changes in the emission rates between the initial stage and later periods of growth. The cultivation on the synthetic agar resulted in MVOC patterns with a wide variety of signals. In contrast, the growth on wet wall paper led to changed MVOC patterns with less signals. The emission rates were drastically reduced. Components emitted by all six fungi species on wall paper were 2-pentanol and 2-pentanone. 1-Octen-3-ol was emitted by five fungi species. 2-Pentanol was only detected in considerable amounts during ...

2008-06-05

46

Synthesis and study of the antifungal activity of new mono- and disubstituted derivatives of a genetically engineered polyene antibiotic 28,29-didehydronystatin A1 (S44HP)  

British Library Electronic Table of Contents (United Kingdom)

Mono- and disubstituted novel derivatives of the heptaene nystatin analog 28,29-didehydronystatin A1 (S44HP, 1) were obtained by chemical modification of the exocyclic C-16 carboxyl and/or an amino group of mycosamine moiety. The strategy of preparation of mono- and double-modified polyene macrolides was based on the use of intermediate hydrophobic N-Fmoc (9-fluorenylmethoxycarbonyl) derivatives that facilitated the procedures of isolation and purification of new compounds. The antifungal activity of the new derivatives was first tested in vitro against yeasts and filamentous fungi, allowing the selection of the most active compounds that were subsequently tested for acute toxicity in mice. 2-(N,N-dimethylamino)ethylamide of 1 (2) and 2-(N,N-dimethylamino)ethylamide of N-fructopyranosyl-28...

2010-01-01

47

Structure and antimicrobial activity relationship of quaternary N-alkyl chitosan derivatives against some plant pathogens  

British Library Electronic Table of Contents (United Kingdom)

In the present work, quaternary chitosans as water-soluble compounds were prepared based on three-step process. Schiff bases were firstly synthesized by the reaction between the amino groups of chitosan with aliphatic aldehydes followed by a reduction with sodium borohydride (NaBH4) to form N-(alkyl) chitosans. N,N,N-(dimethyl alkyl) chitosans were then obtained by a reaction of chitosan containing N-butyl, N-pentyl, N-hexyl, N-heptyl, and N-octyl substituents with methyl iodide. The compounds were characterized using IR and NMR spectroscopy. Subsequent experiments were conducted to test their antimicrobial activities against the most economic plant pathogenic bacteria of crown gall disease Agrobacterium tumefaciens, soft mold disease Erwinia carotovora, fungi of grey mold Botrytis cinerea...

2010-01-01

48

SZ-685C, a marine anthraquinone, is a potent inducer of apoptosis with anticancer activity by suppression of the Akt/FOXO pathway  

British Library Electronic Table of Contents (United Kingdom)

Background and purpose: The aims of this study were to investigate the anti-cancer activity of SZ-685C, an anthracycline analogue isolated from marine-derived mangrove endophytic fungi, and to explore the molecular mechanisms underlying such activity. Experimental approach: The effect of SZ-685C on the viability of cancer cell lines was investigated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. SZ-685C-induced apoptosis was assessed by Annexin V-fluorescein isothiocyanate/propidium iodide staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay and analysis of caspase activation. The effect of SZ-685C on the Akt/FOXO pathway was studied using Western blotting analysis, and the in vivo anti-tumour efficacy was examined in ...

2010-01-01

49

Review on the immunology of European sea bass Dicentrarchus labrax  

British Library Electronic Table of Contents (United Kingdom)

European sea bass (Dicentrarchus labrax L.) is a marine species of great economic importance, particularly in Mediterranean aquaculture. However, numerous pathogenic viruses, bacteria, fungi and parasites affect the species, causing various infectious diseases and thereby leading to the most heavy losses in aquaculture production of sea bass. In this respect, knowledge on molecular and genetic mechanisms of resistance to pathogens and specific features of immune response against various infectious agents should greatly benefit the development of effective vaccines and proper vaccination strategies in marker-assisted selection of fish resistant to a range of infections. To date, genetic knowledge on sea bass immune regulatory genes responsible for resistance to pathogens is relatively poor ...

2007-01-01

50

Responses of Bark Beetle-Associated Bacteria to Host Monoterpenes and Their Relationship to Insect Life Histories  

British Library Electronic Table of Contents (United Kingdom)

Bark beetles that colonize living conifers and their microbial associates encounter constitutive and induced chemical defenses of their host. Monoterpene hydrocarbons comprise a major component of these allelochemicals, and many are antibiotic to insects, fungi, and bacteria. Some bark beetle species exhaust these defenses by killing their host through mass attacks mediated by aggregation pheromones. Others lack adult aggregation pheromones and do not engage in pheromone-mediated mass attacks, but rather have the ability to complete development within live hosts. In the former species, the larvae develop in tissue largely depleted of host terpenes, whereas in the latter exposure to these compounds persists throughout development. A substantial literature exists on how monoterpenes affect b...

2011-01-01

51

Oxidation of Elemental Sulfur by Fusarium solani Strain THIF01 Harboring Endobacterium Bradyrhizobium sp.  

British Library Electronic Table of Contents (United Kingdom)

Nineteen fungal strains having an ability to oxidize elemental sulfur in mineral salts medium were isolated from deteriorated sandstones of Angkor monuments. These fungi formed clearing zone on agar medium supplemented with powder sulfur due to the dissolution of sulfur. Representative of the isolates, strain THIF01, was identified as Fusarium solani on the basis of morphological characteristics and phylogenetic analyses. PCR amplification targeting 16S rRNA gene and analyses of full 16S rRNA gene sequence indicated strain THIF01 harbors an endobacterium Bradyrhizobium sp.; however, involvement of the bacterium in the sulfur oxidation is still unclear. Strain THIF01 oxidized elemental sulfur to thiosulfate and then sulfate. Germination of the spores of strain THIF01 was observed in a liqui...

2010-01-01

52

Mitochondrial NADH:ubiquinone oxidoreductase (complex I) in eukaryotes: A highly conserved subunit composition highlighted by mining of protein databases  

British Library Electronic Table of Contents (United Kingdom)

Complex I (NADH:ubiquinone oxidoreductase) is the largest enzyme of the mitochondrial respiratory chain. Compared to its bacterial counterpart which encompasses 14-17 subunits, mitochondrial complex I has almost tripled its subunit composition during evolution of eukaryotes, by recruitment of so-called accessory subunits, part of them being specific to distinct evolutionary lineages. The increasing availability of numerous broadly sampled eukaryotic genomes now enables the reconstruction of the evolutionary history of this large protein complex. Here, a combination of profile-based sequence comparisons and basic structural properties analyses at the protein level enabled to pinpoint homology relationships between complex I subunits from fungi, mammals or green plants, previously identified...

2011-01-01

53

Microbial keratitis after corneal laser refractive surgery  

British Library Electronic Table of Contents (United Kingdom)

Corneal laser refractive surgery is increasingly being performed on patients with the aim of improving unaided vision. Most candidates for surgery have excellent spectacle- or contact lens-corrected vision. Although microbial keratitis following refractive surgery is a rare complication, and usually has a good visual outcome, it can be sight-threatening. The spectrum of pathogens differs to other causes of microbial keratitis, such as contact lens-associated keratitis, and a different management approach is required. Postoperatively, patients are prescribed topical steroids and broad-spectrum topical antibiotics, typically fluoroquinolones. These do not cover unusual organisms, such as fungi, Nocardia, Acanthamoeba and some atypical mycobacteria. In post-laser-assisted in situ keratomileus...

2011-01-01

54

Fungi of the house dust in Riyadh, Saudi Arabia.  

Science.gov (United States)

30 species belonging to 18 genera were isolated from floor dust of 30 homes in Riyadh. Out of them 16 species and 10 genera were isolated from dust of air conditioners of the same homes. The most common genera in floor dust were Aspergillus, Penicillium and Cladosporium. Aspergillus repens, A. amstelodami, A. versicolor, A. fumigatus, Penicillium purpurogenum, P. crustosum, Cladosporium cladosporoides and C. herbarum were frequently isolated. The most abundant genera in air conditioner dust were Aspergillus and Penicillium. Aspergillus fumigatus, A. ochraceus, A. terreus, Penicillium oxalicium and P. crustosum were most frequent species. PMID:2330766

1990-01-01

55

Flavonols and an oxychromonol from Piliostigma reticulatum  

British Library Electronic Table of Contents (United Kingdom)

The leaf extract from the plant Piliostigma reticulatum was found to exhibit antimicrobial activity against some bacteria and fungi such as Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418), Bacillus subtilis (NCTC 8236), Proteus vulgaris (NCTC 4175), Aspergillus niger (ATCC 10578) and Candida albicans (ATCC 10231). Upon investigation of the chemical constituents present in the leaf extract, a total of seven compounds were isolated and their structures were unambiguously established by spectroscopic methods including HR-MS and NMR spectrometry. Four of the isolated compounds were novel, namely 6-C-methyl-2-p-hydroxyphenyloxychromonol (piliostigmol), 1, 6,8-di-C-methylquercetin-3,3prime,7-trimethyl ether, 2, 6,8-di-C-methylquercetin-3,3prime-dimethyl ether, 3 and 3prime,6,8,-...

2008-01-01

56

Ergosterol analyses of oil palm seedlings and plants infected with Ganoderma  

British Library Electronic Table of Contents (United Kingdom)

Basal stem rot of oil palm (OP) by Ganoderma boninense is of major economic concern and it is the predominant disease of OP in SE Asia. Also, other plantation crops are affected by Ganoderma. The early detection of symptoms is crucial for control, although effective methods remain elusive. Ergosterol is the principal sterol of fungi and plays an essential role in the cell membrane and other cellular constituents. The analysis of ergosterol is useful for fungal detection in solid plant substrates. The present report compares ergosterol concentration in sound and decayed OP seedlings and mature plants using HPLC with diode array detection. The disease of OP requires to be considered as a white rot process where fungal biomass will increase from a low to high level as the infection progresses...

2011-01-01

57

Bioconvertion of spent cellulose sausage casings  

British Library Electronic Table of Contents (United Kingdom)

Cellulose sausage cellulose casings are used extensively in the manufacture of sausages in meat packaging. After stripping the meat, spent casings mainly contain cellulose and residual meat juice with salt, nitrate and nitrite. Disposal of spent sausage casings has serious economic and environmental concerns for the sausage industry. This work describes bioconversion of spent cellulose casings (SCC) into enzymes, lactic acid and ethanol by using cellulolytic fungi, lactobacillus and yeasts. The solid substrate cultivation (SSC) of Trichoderma reesei RUT C-30 on SCC and blends gave a maximum of 152 filter paper cellulase (FPase) activity and about 100 carboxymethylcellulase activity (CMCase)/g dry weight substrate. The SSC produced enzyme-rich casing with 50 FPase when directly mixed as suc...

2008-01-01

58

Gamma radiation effects at color, antioxidant capacity and fatty acid profile in peanut (Arachis hypogaea L.)  

International Nuclear Information System (INIS)

Irradiation is efficient at extinction fungi contamination in peanuts. Peanuts have high biologic value protein, minerals, vitamin E, complex B, and high concentration of lipids. The objective of this research is to evaluate the gamma irradiation effect on color, total phenolic, antioxidant activity, and fatty acid profile in peanuts (Arachis hypogaea L.). Cultivars IAC-Tatu ST and IAC-Runner 886 were submitted to gamma radiation with doses of 5.0; 7.5; 10.0, and 15.0 kGy and storage at room temperature. There was no significant difference in the color of IAC-Tatu ST. However, significant difference was found in the luminosity and Chroma in IAC-Runner 886. Total fenolics differed from the control with 33.27 mg.g-1 and treatment dose of 10.0 kGy with 58.60 mg.g-1 in IAC-Tatu ST. This parameter not had significant difference in IAC-Runner 886 and the control with 51.59 mg.g-1. The antioxidant activity did not present significant difference with a dose of 10.0 kGy, ...

2011-01-01

59

Toxicological benchmarks for screening potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process  

International Nuclear Information System (INIS)

One of the initial stages in ecological risk assessments for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as open-quotes contaminants of potential concern.close quotes This process is termed open-quotes contaminant screening.close quotes It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to soil- and litter-dwelling invertebrates, including earthworms, other micro- and macroinvertebrates, or heterotrophic bacteria and fungi. This report presents a standard method for deriving benchmarks for this purpose, sets of data concerning effects of chemicals in soil on invertebrates and soil microbial processes, and benchmarks for chemicals potentially associated with United States Department of Energy sites. In addition, literature ...

60

Responses to ammonium and nitrate additions by boreal plants and their natural enemies  

Energy Technology Data Exchange (ETDEWEB)

Separate effects of ammonium (NH{sub 4} {sup +}) and nitrate (NO{sub 3} {sup -}) on boreal forest understorey vegetation were investigated in an experiment where 12.5 and 50.0 kg nitrogen (N) ha{sup -1} year{sup -1} was added to 2 m{sup 2} sized plots during 4 years. The dwarf-shrubs dominating the plant community, Vaccinium myrtillus and V. vitis-idaea, took up little of the added N independent of the chemical form, and their growth did not respond to the N treatments. The grass Deschampsia flexuosa increased from the N additions and most so in response to NO{sub 3} {sup -}. Bryophytes took up predominately NH{sub 4} {sup +} and there was a negative correlation between moss N concentration and abundance. Plant pathogenic fungi increased from the N additions, but showed no differences in response to the two N forms. Because the relative contribution of NH{sub 4} {sup +} and NO{sub 3} {sup -} to the total N deposition on a regional scale can vary substantially, the ...

2006-05-15

 
 
 
 
61

Prospects for controlling animal parasitic nematodes by predacious micro fungi.  

Science.gov (United States)

Resistance against anthelmintics is widespread, particularly in parasitic nematode populations of small ruminants. Several new techniques or supplements have been developed or are under investigation. Biological control (BC) is one of these new methods. The net-trapping predacious fungus Duddingtonia flagrans produces thick walled resting spores, chlamydospores, which are able to survive passage through the gastrointestinal tract of cattle, horses, sheep and pigs. Under Danish climatic conditions it has been shown that the number of parasite larvae on pasture and the worm burden of the grazing animals is significantly reduced when animals are fed spores during the initial 2-3 months of the grazing season. Work with D. flagrans in France, Australia, USA, and Mexico has confirmed the strong BC potential of this fungus. Today much work is going into development of suitable delivery systems for grazing livestock worldwide. Ultimately, BC should be implemented in integrated parasite control ...

2000-01-01

62

Pathology of tissue loss (white syndrome) in Acropora sp. corals from the Central Pacific.  

Science.gov (United States)

We performed histological examination of 69 samples of Acropora sp. manifesting different types of tissue loss (Acropora White Syndrome-AWS) from Hawaii, Johnston Atoll and American Samoa between 2002 and 2006. Gross lesions of tissue loss were observed and classified as diffuse acute, diffuse subacute, and focal to multifocal acute to subacute. Corals with acute tissue loss manifested microscopic evidence of necrosis sometimes associated with ciliates, helminths, fungi, algae, sponges, or cyanobacteria whereas those with subacute tissue loss manifested mainly wound repair. Gross lesions of AWS have multiple different changes at the microscopic level some of which involve various microorganisms and metazoa. Elucidating this disease will require, among other things, monitoring lesions over time to determine the pathogenesis of AWS and the potential role of tissue-associated microorganisms in the genesis of tissue loss. Attempts to experimentally induce AWS should ...

2011-03-30

63

Mechanism of biosorption of Heavy metals by mucor rouxii  

Energy Technology Data Exchange (ETDEWEB)

Fungi such as Aspergillus niger and Mucor rouxii are capable of removing heavy metals from aqueous solutions. The role various functional groups play in the cell wall of M. rouxii in metal biosorption of lead, cadmium, nickel and zinc was investigated in this paper. The biomass was chemically treated to modify the functional carboxyl, amino and phosphate groups. These modifications were examined by means of infrared spectroscopy. It was found that an esterification of the carboxyl groups and phosphate and a methylation of the amine groups significantly decreased the biosorption of the heavy metals studied. Thus, the carboxylate, amine and phosphate groups were recognized as important in the biosorption of metal ions by M. rouxii biomass. The role the lipids fraction play was not significant. The study showed that Na, K, Ca and Mg ions were released from the biomass after biosorption of Pb,Cd,Ni and Zn, indicating that ion exchange was a key mechanism in the ...

2008-08-15

64

Induction of mutation in Trichoderma viride for conversion of natural cellulose into glucose  

Energy Technology Data Exchange (ETDEWEB)

The production of cellulolytic enzymes from fungi has been extensively studied. Several mutants of Trichoderma reesei were selected. Most of the studies were carried out on T. reesei, T. viride, T. harzianum, Penicillium funiculosum, Altemaria alternata. Aspergillus phoenicis, A. ustus, A. tamarii, A. japonicus, and A. niger. T. koningii is one of the most active producers of the so-called C, factor, which is indispensable for the rapid and extensive attack on crystal-line cellulose. However, Trichodenna is known to excrete only small amounts of {beta}-glucosidase. Therefore, Trichoderma is supplemented with {beta}-glucosidase from Aspergillus to increase the saccharification rate of cellulose to glucose as the main sugar. Induction of mutations in Trichodenna spp. rather than T. viride as a tool for the enhancement of {beta}-glucosidase activity was reported. Unfortunately, T. reesei is a poor producer of {beta}-glucosidase. On the other hand, T. harzianum M{sub ...

1991-12-31

65

Fermented empty fruit bunch (FEFB) as feed for ruminant animal  

International Nuclear Information System (INIS)

Fermented oil palm empty fruit bunch, now known as 'Sterifeed' has been characterized by physico-chemical properties. It has also been proven to have an improved digestibility (by in vitro and in-vivo test) over the original material. The remaining important aspect of feed to be examined is the long term effect of feeding this material to animals. The size of fermentation media bags used was 0.5 - 1 kg/bag. In the large scale production of these materials, the numbers of bags were increased. The production at pilot scale level reinvestigated the basic processing parameters for the 1 kg/bag media and also performed a trial run for different sizes of bags. These include: 1) investigation on the growth of fungi on fermentation media subjected to different treatment times and the non treated media, 2) evaluation of the processing rate, 3) trial run processing of 25-50 MT oil palm EFB into feed, and 4) processing of different sizes of bags

1998-01-01

66

Evaluation of fungal burden of medicinal plants submitted to gamma radiation process after 30 days  

International Nuclear Information System (INIS)

Forty samples of medicinal plants (Peumus boldus, Camellia sinensis, Maytenus ilicifolia and Cassia angustifolia), purchased from pharmacies and street market in the five cities of Sao Paulo State, were irradiated using a "6"0Co gamma ray source (Gammacell) with a dose of 10.0 kGy, delivered at dose rate of 3.0 kGy/h. Nonirradiated samples were used as controls of fungal isolates. For fungal counts and identification in medicinal plants a serial dilutions from 10"-"1 to 10"-"6 of the samples were seeded in duplicates and plated using the method in Dichloran 18% Glycerol Agar (DG 18) and were counted after five days at 25 deg C. Mycological analysis of control samples revealed the presence of genera Aspergillus and Penicillium, which are known as toxigenic fungi. The process of gamma radiation was effective in reducing the number of colony forming units (cfu/g) in all irradiated samples of medicinal plants after 30 days, using the dose of 10.0 kGy and kept of veiled ...

67

Evaluation of chicken manure, kenaf, and phanerochaete chrysosporium (white rot fungus) as enhancers of polychlorinated biphenyl biodegradation  

Energy Technology Data Exchange (ETDEWEB)

In this 150-day study, chicken manure, kenaf, and white rot fungus were added to soil microcosms in an attempt to enhance the degradation of polychlorinated biphenyls. The soil was contaminated with commercial PCB mixtures. Dishes were ammended with 5% dry weight chicken manure, 1% dry weight kenaf, and 1% dry weight kenaf plus Phanerochaete chrysosporium inoculant. PCB concentrations were determined at 30 day intervals by soxhlet extraction and gas chromatography analyses. Preliminary results of microbial populations and PCB degradation are presented. At 90 days, the microcosms amended with chicken manure had significantly higher populations of bacteria, fungi, and actinomycetes. However, at 120 days, these soils underwent great reductions in actinomycete and bacterial populations. Through 60 days, the concentration of the PCBs Aroclor 1242 and 1248 had its greatest reduction in the kenaf amended soils. The concentration of Aroclor 1260 either increased or stayed ...

1995-12-31

68

Ecology of microorganisms in desert soil environment. Sabaku dojo kankyo ni okeru biseibutsu seitai  

Energy Technology Data Exchange (ETDEWEB)

This paper indicates first that the base content in desert soil is by far much higher than that in soils in moist areas, that salts with the higher solubility to water have their deposition depth greater, and that the organic content is extremely low. The paper also describes the experiments to verify that the desert soil contains soil lumps with a diameter of about several millimeters, which function effectively to form the long term survival locations for microorganisms. Desert soil containing soil lumps and the one removed of lumps by pulverizing them into powder were prepared as test specimens, which were left submerged. It was confirmed that the velocity of decomposing the organics and the mechanical strength in the latter soil are obviously inferior to those in the former soil. Additional remarks are given that when the desert soil environment is changed the microorganisms get more active appreciably and that certain kinds of mold fungi and green algae were ...

1991-11-01

69

Critical loads for vegetation. Definition, use and limits. Charges critiques pour la vegetation  

Energy Technology Data Exchange (ETDEWEB)

Vegetation is a key compartment of ecosystems. It contains a large part of the biodiversity at the species level. For the evaluation of critical loads, we have to separate different receptors: lower plants (algae, fungi, lichens and mosses) and vascular plants. Trees must be distinguished due to their economic value. We analyze the different changes that pollution produces on vegetation: the state of health of individuals, changes in the biology and genetics at the population level, changes in the biodiversity or the specific composition at the community level. Calculation of critical loads is based on observational or experimental studies, in more or less controlled environments. However, they cannot yet be obtained through models of vegetation changes. Some results have been acquired at the European level, mainly for critical loads for nitrogen, but these results have come mostly from Northern Europe. Moreover, only heathlands and acidic forests have been studied ...

1993-06-01

70

Biological control of take-all in wheat by endophytic Bacillus subtilis E1R-j and potential mode of action  

British Library Electronic Table of Contents (United Kingdom)

The bacterial strain E1R-j, isolated as an endophyte from wheat roots, exhibited high antifungal activity to Gaeumannomyces graminis var. tritici (Ggt). Strain E1R-j was identified as Bacillus subtilis based on morphological, physiological and biochemical methods as well as on 16S rDNA analysis. This strain inhibited mycelium growth in vitro of numerous plant pathogenic fungi, especially of Ggt, Coniothyrium diplodiella, Phomopsis sp. and Sclerotinia sclerotiorum. In greenhouse experiments, soil drenches with cell densities of 106, 109 and 1012CFU ml-1 E1R-j reduced significantly take-all disease, caused by Ggt, in wheat seedling by 62.6%, 68.6% and 70.7%, respectively, compared to the inoculated control, 4weeks after sowing. Growth parameters such as lengths and fresh weights of roots and...

2009-01-01

71

Antifungal thiopeptide cyclothiazomycin B1 exhibits growth inhibition accompanying morphological changes via binding to fungal cell wall chitin  

British Library Electronic Table of Contents (United Kingdom)

Cyclothiazomycin B1 (CTB1) is an antifungal cyclic thiopeptide isolated from the culture broth of Streptomyces sp. HA 125-40. CTB1 inhibited the growth of several filamentous fungi including plant pathogens along with swelling of hyphae and spores. The antifungal activity of CTB1 was weakened by hyperosmotic conditions, and hyphae treated with CTB1 burst under hypoosmotic conditions, indicating increased cell wall fragility. CTB1-sensitive fungal species contain high levels of cell wall chitin and/or chitosan. Unlike nikkomycin Z, a competitive inhibitor of chitin synthase (CHS), CTB1 did not inhibit CHS activity. Although CTB1 inhibited CHS biosynthesis, the same result was also obtained with a non-specific proteins inhibitor, cycloheximide, which did not reduce cell wall rigidity. These ...

2011-01-01

72

On the impact of low power density microwaves in some living tissues  

Energy Technology Data Exchange (ETDEWEB)

The biomedical and ecological interest for the microwave impact on the Earth biosphere is continuously increased since the industrial, military and communication activities strongly contribute to the electromagnetic stress of living bodies. In the next the authors present some of the main results obtained regarding the microwave exposure of various types of biological material: bacteria, fungi, young plant seedlings, dry seeds, animal tissues. The electromagnetic exposure was carried out in open space in well controlled environmental conditions by using 10.75 GHz/1 m W cm{sup -2} microwaves. Biochemical assays and cytogenetic tests have been carried out to reveal the changes induced post irradiation. The response of some pathogen bacteria, have been emphasized by means of turbidimetric measurements - the stimulatory effect being noticed at the level of the microbial population density (the stimulation of the human body microbial flora seems to be one of the side ...

2006-07-01

73

Microbial remediation of soil pollution from ore mining. Part 3: Cyanide removal and biosorption of heavy metals in mining and processing water; Untersuchungen zur mikrobiellen Sicherung von Erzbergbaualtlasten. Teilvorhaben 3: Cyanidabbau und Biosorption von Schwermetallen in Abwaessern aus Erzbergbau- und Aufbereitungsbetrieben. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

1. Cyanide degradation: Of the cyanide- and thiocyanate-degrading bacteria, Burkholderia cepacia and Pseudomonas spec. were the most effective. 2. Biosorption: Of the isolates suited for biosorption of heavy metals, 597-A (non-identifiable) and 597-A2 (Aspergillus fumigatis) had the biggest potential. The sorption capacity of the fungi for metals varied with the C source used for their growth: apple juice > molasses > glucose. The fungi are not cyanide-sensitive and can even degrade cyanide. Living biomass had better metal sorption efficiencies than dead mycelium. The biosorption rates in waste water were usually higher than in broth. Depending on the metal composition and concentrations and on the exposure time and volume of the mycelia, up to 85 % of the initial concentration was removed from the liquid phase. The capacity of different biomasses for the sorption of metal mixtures was between 65 and 80 mg/g of dry matter ...

1999-12-01

74

Research work on mutation breeding in Egypt during the 1980s  

International Nuclear Information System (INIS)

The research work carried out on mutation breeding in Egypt during the 1980s is summarized. Several mutations have been developed in bread wheat, maize, rice and barley. A higher yield, tolerance to salinity, shorter types and earliness were obtained after use of different mutagens and growth regulators. Great attention has been paid to the fababean and chickpea, particularly in improving their quality and quantity of protein, and their resistance to insect weevils such as Callosobruchus sp. Tolerance or resistance to broom rape has also been reported. Various grain legumes such as lentil, pea, cowpea, bean, fenugreek and lupin received some attention. Mutation work on fibre crops such as cotton, kenaf and flax has led to some promising results. Zero type, glandless and early maturing mutants were obtained in cotton, and early flowering, high yielding (fibre or oil) mutants in flax. Some attention has been given to oil crops such as sesame, rapeseed, peanuts, castorbean, sunflower and ...

1990-06-18

75

Physiological responses of Pinus sylvestris to changing carbon dioxide and ozone concentrations  

Energy Technology Data Exchange (ETDEWEB)

The objective of this research is to study the effects of elevated ozone, carbon dioxide and their combination on ultrastructural, physiological and biochemical responses of Scots pine needles and how these effects are reflected to photosynthesis, carbohydrate and nutrient allocation and finally to shoot and root growth of trees. In addition the interactions of the studied trees and mycorrhizal fungi as well as insect herbivores are studied. The exposures have been running only for two growing periods and it seems necessary to continue the experiment over the third growing season in 1996. Since the analyses are partially incomplete, only preliminary conclusions are possible at the moment. The slightly increased shoot growth and needle width and increased amount of starch in chloroplasts point to the slight stimulating effect of elevated CO{sub 2} among the chamber treatments. Altogether the growth of the seedlings was best in the chamberless treatment indicating a ...

1996-12-31

76

Molecular evolution and characterization of fungal indoleamine 2,3-dioxygenases.  

Science.gov (United States)

Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) are tryptophan-degrading enzymes. Mammalian IDO expression is induced by cytokines and has antimicrobial and immunomodulatory effects. A major role of mammalian TDO is to supply nicotinamide adenine dinucleotide (NAD(+)). In fungi, the IDO homologue is thought to be expressed constitutively and supply NAD(+), as TDO is absent from their genomes. Here, we reveal the distribution of IDO genes among fungal species and characterize their enzymatic activity. The yeast, Saccharomyces cerevisiae has only one IDO gene, whereas the koji-mold, Aspergillus oryzae has two genes, IDO? and IDO?. The A. oryzae IDO? showed more similar enzymatic properties to those of S. cerevisiae IDO than IDO?, suggesting that the A. oryzae IDO? is a functional homologue of the S. cerevisiae IDO. From the IDO? gene, two isoforms, IDO? and IDO?(+) could be generated by alternative splicing. The latter contained a 17 amino ...

2010-12-18

77

Evaluation of fungal bio burden and mycotoxins presence in irradiated samples of medicinal plants purchased from wholesale and retail market  

International Nuclear Information System (INIS)

This present study evaluated the effect of gamma radiation on the fungal survival in packed medicinal plants, purchased from wholesale and retail market, in different period (0 and 30 days) after the treatment. Five kind of medicinal plants (Peumus boldus, Camellia sinensis, Maytenus ilicifolia, Paullinia cupana and Cassia angustifolia), were collected from different cities of Sao Paulo State, and submitted to irradiation treatment using a 60Co source (type Gammacell 220) with doses of 5,0 kGy and 10 kGy and at dose rate of 3.0 kGy/h. Non-irradiated samples (control group) were used for fungal counts and serial dilutions from 10-1 to 10-6 of the samples were seeded in duplicates and plated using the surface culture method in Dichloran 18% Glycerol Agar (DG 18) and were counted after five days at 25 deg C. The control group revealed the presence of genera Aspergillus and Penicillium, which are known as toxigenic fungi and a few samples of control group were within ...

2006-12-20

78

Biosorption of heavy metals  

Energy Technology Data Exchange (ETDEWEB)

Only within the past decade has the potential of metal biosorption by biomass materials been well established. For economic reasons, of particular interest are abundant biomass types generated as a waste byproduct of large-scale industrial fermentations or certain metal-binding algae found in large quantities in the sea. These biomass types serve as a basis for newly developed metal biosorption processes foreseen particularly as a very competitive means for the detoxification of metal-bearing industrial effluents. The assessment of the metal-building capacity of some new biosorbents is discussed. Lead and cadmium, for instance, have been effectively removed from very dilute solutions by the dried biomass of some ubiquitous species of brown marine algae such as Ascophyllum and Sargassum, which accumulate more than 30% of biomass dry weight in the metal. Mycelia of the industrial steroid-transforming fungi Rhizopus and Absidia are excellent biosorbents for lead, ...

1995-05-01