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Polish Journal of Microbiology 2009The aim of this study was to isolate and identify endophytic bacteria from stems of Chelidonium majus L. (greater celandine) and to evaluate their antifungal properties....
The aim of this study was to isolate and identify endophytic bacteria from stems of Chelidonium majus L. (greater celandine) and to evaluate their antifungal properties. In total, 34 bacterial endophyte strains were isolated. The fungistatic effects of these bacteria on the growth of five moulds (Alternaria alternata, Chaetonium sp., Paecilomyces variotti, Byssochlamys fulva, Aureobasidium pullulans) and one species of black yeast (Exophiala mesophila) were tested. The majority of the bacterial isolates were found to inhibit the growth of fungi and those with the strongest antifungal properties were further characterized. Of the twelve isolates examined, 11 were species of Bacillus thuringiensis and one was Bacillus amyloliquefaciens.
Topics: Bacteria; Chelidonium; DNA, Bacterial; DNA, Ribosomal; Fungi; Plant Components, Aerial
PubMed: 20380146
DOI: No ID Found -
Journal of Food Protection Apr 2012Patulin, a mycotoxin produced by several genera of fungi, including Byssochlamys, Aspergillus, and Penicillium, has been an important concern in apple cider and apple... (Comparative Study)
Comparative Study
Patulin, a mycotoxin produced by several genera of fungi, including Byssochlamys, Aspergillus, and Penicillium, has been an important concern in apple cider and apple juice due to its toxicity and health consequences. In this study, the effects of UV on the patulin level, physical and chemical properties, and sensory attributes in apple juice from concentrate were investigated. Kinetic modeling of patulin reduction by UV radiation in apple juice from concentrate was calculated and compared with the degradation rate observed previously in apple cider. From an initial patulin contamination of approximately 1,000 ppb (μg/liter), the UV exposure, ranging from 14.2 mJ/cm(2) (one pass) to 99.4 mJ/cm(2) (seven passes), was successful in reducing patulin levels by 72.57% ± 2.76% to 5.14% ± 0.70%, respectively. Patulin reduction by UV radiation followed first-order kinetic modeling in a fashion similar to first-order microbial inactivation. An exponential correlation between UV exposure and the percentage of patulin remaining was observed, giving an r(2) value of 0.9950. Apple juice was repeatedly exposed to 14.2 mJ/cm(2) for each treatment, and patulin levels were significantly decreased when compared with the level obtained with the previous UV exposure treatment. While there were no significant differences in the percentages of titratable acidity and ascorbic acid (P > 0.05), there were minor yet random sampling differences in pH and degrees Brix (1 °Brix is 1 g of sucrose in 100 g of solution; the °Brix represents the soluble solids content of the solution as percentage by weight [%, wt/wt]) (P ≤ 0.05). A significant difference (P ≤ 0.05) in sensory perception for the finished apple juice was detected between the control and the full seven-pass UV radiation treatment using an experienced consumer panel and a triangle test. Patulin reduction by UV radiation from both the current study and a previous study involving apple cider was compared, which showed that both matrices strongly fit a first-order kinetic degradation model. However, the kinetic constant for degradation in apple juice was approximately 5.5 times greater than that observed in an apple cider matrix.
Topics: Beverages; Consumer Product Safety; Dose-Response Relationship, Radiation; Food Contamination; Food Handling; Food Irradiation; Humans; Hydrogen-Ion Concentration; Kinetics; Malus; Models, Biological; Patulin; Taste; Ultraviolet Rays
PubMed: 22488060
DOI: 10.4315/0362-028X.JFP-11-429 -
Irish Veterinary Journal 2014A three year old male entire Staffordshire bull terrier was referred to University College Dublin Veterinary Hospital, with a two week history of fever, inflammation of...
A three year old male entire Staffordshire bull terrier was referred to University College Dublin Veterinary Hospital, with a two week history of fever, inflammation of the right hock, lameness on the right hindlimb, peripheral lymphadenopathy and gastrointestinal signs (vomiting and diarrhoea). For the preceding three months the dog had been treated for atopic dermatitis with oral ciclosporin (5 mg/kg, PO, q 24 hours). Cytological analysis of the affected lymph nodes demonstrated fungal-like organisms predominantly contained within macrophages. Subsequent fungal culture and microscopic identification confirmed the presence of a Byssochlamys sp. This fungus is a saprophytic organism which has been associated with mycotoxin production. It has not previously been identified as a cause of systemic infection in animals or humans. Ciclosporin was discontinued, and a second generation triazole, voriconazole prescribed at a dose of 6 mg/kg for the first two doses, and continued at 3 mg/kg every 12 hours for six months. There was an excellent response. Follow-up examination five weeks after treatment was completed confirmed remission of the disease. The dog remains alive and well three years later. The present case represents an unusual fungal infection in a dog secondary to immunosuppressive therapy with ciclosporin. Such a possibility should be considered in animals presenting with signs consistent with systemic infection when receiving immunosuppressive medication.
PubMed: 25132957
DOI: 10.1186/2046-0481-67-17 -
Chemical Communications (Cambridge,... Dec 2015The filamentous fungus Byssochlamys fulva strain IMI 40021 produces (+)-byssochlamic acid 1, its novel dihydroanalogue 2 and four related secondary metabolites....
Novel nonadride, heptadride and maleic acid metabolites from the byssochlamic acid producer Byssochlamys fulva IMI 40021 - an insight into the biosynthesis of maleidrides.
The filamentous fungus Byssochlamys fulva strain IMI 40021 produces (+)-byssochlamic acid 1, its novel dihydroanalogue 2 and four related secondary metabolites. Agnestadrides A, 17 and B, 18 constitute a novel class of seven-membered ring, maleic anhydride-containing (hence termed heptadride) natural products. The putative maleic anhydride precursor 5 for both nonadride and heptadride biosynthesis was isolated as a fermentation product for the first time and its structure confirmed by synthesis. Acid 5 undergoes facile decarboxylation to anhydride 6. The generic term maleidrides is proposed to encompass biosynthetically-related compounds containing maleic anhydride moieties fused to an alicyclic ring, varying in size and substituents.
Topics: Byssochlamys; Furans; Maleates; Maleic Anhydrides; Molecular Structure
PubMed: 26452099
DOI: 10.1039/c5cc06988b -
Food Science and Biotechnology Jun 2018A total of fourteen roasted coffee samples were collected from different local markets in Nayarit, Mexico. Twenty-two fungi isolates were related to the genera (54.54%)...
A total of fourteen roasted coffee samples were collected from different local markets in Nayarit, Mexico. Twenty-two fungi isolates were related to the genera (54.54%) and (4.5%). The strains R16 (0.33 μg/kg), 6N (1.16 μg/kg) and 11 (0.36 μg/kg) tested positive for OTA (ochratoxin A) production in PDA, the other fungi samples were not toxigenic. According to the sequence analysis of their ITS1-5.8S-ITS2 rDNA region, fungi OTA producers correspond to , and . These three strains were able to produce OTA when inoculated in roasted coffee in concentrations ranging from 75 to 90 μg/kg, after 21 days. Different production stages of roasted coffee (crop management, postharvest practices and storage) along with environmental conditions do not ensure mycotoxigenic fungi free products. This is the first report of OTA natural occurrence in roasted coffee from Nayarit.
PubMed: 30263816
DOI: 10.1007/s10068-017-0288-7 -
Food Research International (Ottawa,... Nov 2020Contamination by spores is often the cause of fungal food spoilage. Some distinct strains of the food spoilage fungus Paecilomyces variotii are able to produce airborne...
Contamination by spores is often the cause of fungal food spoilage. Some distinct strains of the food spoilage fungus Paecilomyces variotii are able to produce airborne conidia that are more heat-resistant than similar species. These ellipsoid asexual spores can vary in size between strains, but also within strains. Here, we compared four measurement techniques to measure conidia size and distribution of five heat-sensitive and five heat-resistant P. variotii strains. Light microscopy (LM), Scanning Electron Microscopy (SEM) and Coulter Counter (CC) were used to measure and compare the spherical equivalent diameter, while CC and flow cytometry were used to study spore size distributions. The flow cytometry data was useful to study spore size distributions, but only relative spore sizes were obtained. There was no statistic difference between the method used of spore size measurement between LM, SEM and CC, but spore size was significantly different between strains with a 2.4-fold volume difference between the extremes. Various size distribution and shape parameters were correlated with conidial heat resistance. We found significant correlations in mean spore size, aspect ratio, roundness and skewness in relation to heat resistance, which suggests that these parameters are indicative for the conidial heat resistance of a P. variotii strain.
Topics: Byssochlamys; Food Microbiology; Hot Temperature; Paecilomyces; Spores, Fungal
PubMed: 33233149
DOI: 10.1016/j.foodres.2020.109514 -
Applied and Environmental Microbiology Dec 1977Ten strains of Byssochlamys fulva and three strains of B. nivea were cultured in a laboratory medium and tested for their ability to produce patulin. Two strains of B....
Ten strains of Byssochlamys fulva and three strains of B. nivea were cultured in a laboratory medium and tested for their ability to produce patulin. Two strains of B. fulva and all three strains of B. nivea produced the mycotoxin. One strain of B. fulva produced patulin in 11 of 13 processed fruit juices, with greatest amounts being produced in blueberry, red raspberry, and boysenberry juices, whereas no patulin was detected in prune or tomato juices. Grown in Concord grape juice at 18, 25, 30, and 38 degrees C, this strain produced the highest patulin concentration at 18 degrees C after 25 days, whereas biomass production was greatest at 25 and 30 degrees C after 20 and 25 days.
Topics: Ascomycota; Beverages; Food Contamination; Food Microbiology; Fruit; Patulin; Pyrans; Saccharomycetales; Species Specificity
PubMed: 596876
DOI: 10.1128/aem.34.6.791-796.1977 -
Environmental Microbiology Feb 2015Ascospores of Neosartorya, Byssochlamys and Talaromyces can be regarded as the most stress-resistant eukaryotic cells. They can survive exposure at temperatures as high...
Ascospores of Neosartorya, Byssochlamys and Talaromyces can be regarded as the most stress-resistant eukaryotic cells. They can survive exposure at temperatures as high as 85°C for 100 min or more. Neosartorya fischeri ascospores are more viscous and more resistant to the combined stress of heat and desiccation than the ascospores of Talaromyces macrosporus which contain predominantly trehalose. These ascospores contain trehalose-based oligosaccharides (TOS) that are novel compatible solutes, which are accumulated to high levels. These compounds are also found in other members of the genus Neosartorya and in some other genera within the order Eurotiales that also include Byssochlamys and Talaromyces. The presence of oligosaccharides was observed in species that had a relatively high growth temperature. TOS glasses have a higher glass transition temperature (Tg ) than trehalose, and they form a stable glass with crystallizing molecules, such as mannitol. Our data indicate that TOS are important for prolonged stabilization of cells against stress. The possible unique role of these solutes in protection against dry heat conditions is discussed.
Topics: Dehydration; Food Microbiology; Hot Temperature; Neosartorya; Prevalence; Spores, Fungal; Stress, Physiological; Talaromyces; Temperature; Trehalose; Viscosity
PubMed: 25040129
DOI: 10.1111/1462-2920.12558 -
Journal of Food Protection Oct 2015Heat-resistant fungal spores present a processing challenge for beverages and fruit juices, as thermal and UV strategies are often inadequate in reducing heat-resistant...
Heat-resistant fungal spores present a processing challenge for beverages and fruit juices, as thermal and UV strategies are often inadequate in reducing heat-resistant fungal burdens to acceptable levels. While effective against pathogenic or invasive bacteria, germicidal UV light treatments also fail to achieve an appreciable reduction of heat-resistant fungal spores. As an alternative, the efficacy of the antifungal protein YvgO was examined across a selection of fruit juices and teas, as well as solid model matrices. Compared with its efficacy in analogous liquid matrices, the apparent efficacy of YvgO was diminished on acidified solid matrices due to a reduction in YvgO diffusion. Using an XTT [2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] tetrazolium dye cytotoxicity assay, the effective concentrations to reduce growth by 50% were elucidated in samples challenged with Byssochlamys fulva H25. The MICs were determined and ranged from 2 ppm in apple juice and acidified teas to approximately 3 to 12 ppm for lemonade and orange, white cranberry, blueberry, prune, cherry, and grape juices. Apple cider and nonacidified teas showed reduced efficacy, with MICs exceeding 100 ppm. Tannin-rich products readily removed YvgO from the product, impairing its efficacy. Adding bovine serum albumin as a competitive inhibitor effectively reversed the YvgO-tannin association and restored efficacy in black but not green tea matrices. When challenged with a 5-log CFU inoculum of B. fulva, the shelf lives of the products were extended for various times up to 28 days in a concentrationdependent manner. However, initial efficacy was not predictive of shelf life extension, as some products exhibited improved protection at just two- and fourfold concentrations above the MIC, while others only exhibited long-term stability when concentrations exceeded 20 times the MIC. As such, YvgO may be an attractive alternative to currently available protection strategies and will provide needed diversity for natural food protectants.
Topics: Antifungal Agents; Byssochlamys; Electrophoresis, Polyacrylamide Gel; Food Contamination; Food Irradiation; Food Microbiology; Fruit; Fruit and Vegetable Juices; Hot Temperature; Hydrogen-Ion Concentration; Microbial Sensitivity Tests; Spores, Fungal; Tea; Ultraviolet Rays
PubMed: 26408134
DOI: 10.4315/0362-028X.JFP-15-128 -
Genome Announcements Mar 2018sp. isolate BYSS01 (anamorph, sp.), which was isolated from jet fuel, is highly adapted to grow in hydrocarbons, having predicted genes involved in degradation of...
sp. isolate BYSS01 (anamorph, sp.), which was isolated from jet fuel, is highly adapted to grow in hydrocarbons, having predicted genes involved in degradation of -alkanes, branched alkanes, and aromatic compounds. The draft genome size is estimated at 29 Mb, containing 8,509 proteins.
PubMed: 29519843
DOI: 10.1128/genomeA.00164-18