Showing papers on "Trichoderma longibrachiatum published in 2000"

Otitis externa due to Trichoderma longibrachiatum.

Abstract: Fungi are occasional pathogens in otitis externa, mainly in chronic infections [1]. Aspergillus spp., the main pathogens of otomycosis, are responsible for 54–80% of cases [2, 3]. We report here a well-documented case of otitis externa due to Trichoderma longibrachiatum. The identification was confirmed by direct sequencing of a fragment coding for the ribosomal DNA. This case and other reports in the literature illustrate the wide spectrum of fungal pathogens isolated in otomycosis and the growing importance of molecular biology in the field of identification in medical mycology.

Inhibition of ruminant feed enzyme polysaccharidase activities by extracts from silages

Abstract: Extracts from 14 barley silages inhibited endo-1, 4-β-xylanase and α-amylase activities of a ruminant feed enzyme additive from Trichoderma longibrachiatum by 23 to 50% but had little effect on cellulase activity. The inhibitory factor(s) were <10 kDa in size and were stable to autoclaving. These observations may explain why feed enzymes are generally less effective when applied to silages than when applied to dry feeds. Key words: Silage, fibrolytic enzymes, Trichoderma, xylanase, inhibitors

Evaluation of biological seed treatment of wheat for the control of seed-borne Fusarium culmorum.

Abstract: A 2-year field study was conducted for two experiments to evaluate the effectiveness of selected antagonists against Fusarium culmorum. Durum winter wheat seeds 'Vitron', naturally infected by F. culmorum at the rate of 20 %, were coated with conidial suspensions (1 x 10 8 conidia/ml) of five antagonistic fungi; Trichoderma atroviride 312, T. longibrachiatum 9, T. harzianum 144, Gliocladium roseum 11 and Penicillium frequentans and added to talcum powder for the first experiment. For the second one, seeds were treated with talcum + yeast (0.2 %) and G. roseum or T. harzianum. All biological treatments, compared to the infected control, gave a significant increase in emergence, winter survival, number of heads and yield, and lower disease incidence and severity in both experiments in both years. The addition of yeast slightly reduced the number of diseased plants. These results show that F. culmorum infecting wheat can be partially controlled by biological seed dressing treatments and even if chemicals (prochloraz + mancozeb, guazatine, tebuconazole + thiram) provide the best disease control, they do not assure a complete absence of the disease at the end of the crop season.

Heterologous expression in Aspergillus nidulans of a Trichoderma longibrachiatum endoglucanase of enological relevance.

Abstract: An Aspergillus nidulans transformant expressing the Trichoderma longibrachiatum endoglucanase 1 gene (egl1) has been constructed. The extracellular production of EGL1 in different culture media has been studied, and a medium has been found in which EGL1 is the predominant extracellular protein produced. The enzymatic properties of the heterologously produced EGL1 are very similar to those of the native enzyme. Grape maceration in the presence of culture filtrate enriched in EGL1 resulted in increased release of aroma precursors, particularly in the case of aromatic grapes. Cryoscanning electron microscopy of the flesh of grapes treated with EGL1-enriched culture filtrate revealed degradation of the cell wall matrix.

PCR with degenerate primers amplifies a subgenomic DNA fragment from the endoglucanase gene(s) of Torula thermophila, a thermophilic fungus.

Abstract: The aim of this study was to enable the polymerase chain reaction (PCR) amplification of DNA fragments within endoglucanase gene(s) of Torula thermophila, by using degenerate primers so that the amplified fragment(s) could be used as homologous probe(s) for cloning of full-length endoglucanase gene(s). The design of the degenerate PCR primers was mainly based on the endoglucanase sequences of other fungi. The endoglucanase gene sequence of Humicola insolens was the only sequence from a thermophilic fungus publicly available in the literature. Therefore, the endoglucanase sequences of the two Trichoderma species, Trichoderma reesei and Trichoderma longibrachiatum, were used to generalize the primers. PCR amplification of T. thermophila genomic DNA with these primers resilied in a specific amplification. The specificity of the amplified fragment was shown by Southern hybridization analysis using egl3 gene of T. reesei as probe. This result suggested that the degenerate primers used in this study may be of value for studies aimed at cloning of endoglucanase genes from a range of related fungi.